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- Title
- MOLECULAR TYPING OF MYCOBACTERIAL ISOLATES CULTURED FROM THE TISSUE OF INFLAMMATORY BOWEL DISEASE (CROHN'S DISEASE) PATIENTS.
- Creator
-
Adams, Leanne M, Naser, Saleh, University of Central Florida
- Abstract / Description
-
The role of Mycobacterium avium subsp paratuberculosis (MAP) in the etiology and pathogenesis of inflammatory bowel disease (IBD) including Crohn's Disease (CD), has been investigated. The fastidious characteristics and cross reactivity of MAP with other members in Mycobacteria have produced significant challenges in their detection and identification. In this two year pilot study, an array of three PCR molecular assays based on the detection of sequences from the16S rRNA, IS1245, and IS900...
Show moreThe role of Mycobacterium avium subsp paratuberculosis (MAP) in the etiology and pathogenesis of inflammatory bowel disease (IBD) including Crohn's Disease (CD), has been investigated. The fastidious characteristics and cross reactivity of MAP with other members in Mycobacteria have produced significant challenges in their detection and identification. In this two year pilot study, an array of three PCR molecular assays based on the detection of sequences from the16S rRNA, IS1245, and IS900 genes, belonging to members of the MAC, have been developed and optimized into a common protocol to be used as a rapid and accurate diagnostic tool regarding M. avium complex (MAC) infection. The PCR protocol time was reduced by half, and the sensitivity and specificity of the molecular assays has been significantly improved barring the need for southern hybridization. This improved methodology was employed for the molecular typing of MAC in 100 resected, full-thickness tissue samples removed from IBD patients. The tissue samples were homogenized, decontaminated, and inoculated into two mycobacterial culture media systems. A total of 328 Bactec and Mycobacteria Growth Indicator Tube (MIGT) cultures were evaluated for positive MAC growth. Harvested cells were then subjected to genomic DNA extraction and subsequent PCR typing. The I6 S rRNA-based PCR resulted in detection of 26/28 (93%) MAC in Bactec cultures. Specifically, 25/28 (89%) of positive MAC indicated the presence of IS1245 specific to M. avium subsp avium (MAV), and 6/28 (21%) produced results consistent with the presence of IS900 following nested PCR. Moreover, 20/100 (20%) of MGIT cultures were positive for MAP. Sequence analysis was performed on amplified regions of the IS900 element from seven isolates. A nucleotide alignment revealed that 2/7 isolates demonstrated 100% homology to Bovine MAP and 5/7 isolates showed 96-99% homology to sequenced Bovine MAP published in GenBank. The detection of at least two Bovine derived MAP in IBD tissue will have great impact on the epidemiology and reclassification of IBD. The significant homology of the other five isolates to Bovine derived MAP suggests a diversity in the geographical distribution of MAP regarding Johne's disease and CD. Ultimately, the etiology, diagnosis, and the treatment of IBD as well as control and prevention measures may be enhanced with better tools for investigating emerging infectious diseases.
Show less - Date Issued
- 2004
- Identifier
- CFE0000031, ucf:46125
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000031
- Title
- CELLULAR IMMUNE RESPONSE AND GENE EXPRESSION PROFILING IN CROHN'S DISEASE PATIENTS ASSOCIATED WITH MYCOBACTERIUM AVIUM SUBSPECIES PARATUBERCULOSIS.
- Creator
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Romero, Claudia, Naser, Saleh A., University of Central Florida
- Abstract / Description
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Despite the chronic debate in the etiology of crohn's disease (cd), a debilitating inflammatory bowel disease (ibd) closely related to ulcerative colitis (uc), an emerging interest in a possible mycobacterial role has been marked. Granuloma and pathologic manifestations in cd resemble aspects found in tuberculosis, leprosy and paratuberculosis. The latter, a chronic enteritis in cattle, goat, sheep and primates, which is similar to human enteritis, also known as cd, is caused by a fastidious,...
Show moreDespite the chronic debate in the etiology of crohn's disease (cd), a debilitating inflammatory bowel disease (ibd) closely related to ulcerative colitis (uc), an emerging interest in a possible mycobacterial role has been marked. Granuloma and pathologic manifestations in cd resemble aspects found in tuberculosis, leprosy and paratuberculosis. The latter, a chronic enteritis in cattle, goat, sheep and primates, which is similar to human enteritis, also known as cd, is caused by a fastidious, slow growing mycobacterium avium subspecies paratuberculosis (map). Due to the similarities between cd and paratuberculosis, a mycobacterial cause in cd has been proposed. Recent discovery of a possible association between nod2/card15 mutations and risk of cd added support to microorganism-host interactions. In this study, a possible mycobacterial role in cd etiology has been evaluated by investigating the presence of map dna, the state of the cellular immune response and microarray gene expression profiling in peripheral blood and surgical tissue from cd, uc and healthy control subjects. Nested pcr detected map dna in tissue from 10/12(83%) cd patients compared to 1/6(17%) non-ibd subjects. Fluorescence in situ hybridization (fish) with the aid of confocal scanning laser microscopy (cslm) detected map dna in 8/12(67%) cd subjects compared to 0/6(0%) in non-ibd subjects. The detection of map dna by either technique in tissue from cd subjects is significant compared to non-ibd subjects (p < 0.05). Map dna was also detected in both inflamed and non-inflamed tissue from patients with cd suggesting map infiltration in human tissue. Correlation of possible map presence and the function of polymorphonuclear leukocytes (pmn) and peripheral blood mononuclear cells (pbmc) in 19 cd patients and 12 controls have been evaluated. Pmn phagocytosis of viable fitc-map was suppressed in 13/19(68%) cd patients compared to 0/12(0%) in healthy controls (p<0.05). Pbmc phagocytosis of viable fitc-map was suppressed in 5/19(26%) of cd patients compared to 0/12(0%) of healthy controls (p<0.05). The proliferative response of pbmc with t-cell majority from cd and controls subjects was evaluated against pha, candida albicans, pwm and map ppd. Dysfunctional proliferative response against pha was found in 8/19(42%) cd patients compared to 1/12(8.3%) in controls suggesting possible t-cell anergy. Pbmc from 11 cd subjects reacted normally to pha, 7/11(64%) reacted strongly to map ppd suggesting previous exposure to mycobacteria, and 3/11(27%) did not react with map ppd suggesting lack of pre-exposure to mycobacteria. From the seven mycobacterial pre-exposed samples, 6/7(86%) showed a normal ability to recall antigens by activated macrophages when exposed to c. Albicans, and all 7 samples had a normal pwm response. Finally, microarray-chip technology was employed to identify the expression profile of genes that have a role in the immune response of cd patients. Rna was isolated from fresh buffy coats from 8 healthy controls, 2 cd, and 1 uc patients. Chips with an estimated of 30,000 human genes were hybridized to cdna from these samples. We found that 17% of the total number of genes was differentially expressed. Over 200 genes were involved in the immune response, 7 genes where common to both forms of ibd (uc and cd), and 8 genes were found to be either downregulated in cd and upregulated in uc or viceversa. The ifngr1 gene, which encodes the ligand-binding chain of the ifn-gamma receptor, was found to be downregulated in 2/2(100%) of cd patients, but not in uc patients. It is known that defects in ifngr1 are a cause of atypical mycobacterial infection and bcg infection. Patients suffering from this deficiency have an immunologic defect predisposing them to infection with mycobacteria. This correlates with the proposed theory as map being the causative agent of cd. Furthermore, the results indicate a host susceptibility requirement for the establishment of mycobacterial infection in cd patients. Further characterization of ifngr1 using real-time pcr is underway. Collectively, detection of map dna in the majority of cd tissue and the alteration in pmn and pbmc to respond efficiently to map may be related to the fact that mycobacterial pathogens infect phagocytic cells of susceptible hosts and consequently the immune response is dysregulated. Furthermore, the fact that a gene linked to mycobacterial susceptibility was found to be downregulated in cd patients only, strengthens the mycobacterial etiology of cd. In general, the data suggest a possible role for a bacterial pathogen in cd pathogenesis.
Show less - Date Issued
- 2004
- Identifier
- CFE0000170, ucf:46170
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000170
- Title
- CORRELATION OF RPOB GENE MUTATION WITH CLINICAL RIFABUTIN AND RIFAMPICIN RESISTANCE FOR TREATMENT OF CROHN'S DISEASE.
- Creator
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Beckler, Daniel, Naser, Saleh, University of Central Florida
- Abstract / Description
-
Emerging rise in microbial drug resistance and the slow-growing characteristic of some intracellular pathogens such as MAP (Mycobacterium avium subspecies paratuberculosis) strongly urges the need for an effective approach for unconventional drug susceptibility testing. We designed a molecular-based PCR method for the evaluation of rifabutin (RFB) and rifampicin (RIF) resistance based on probable determinant regions within the rpoB gene of MAP, including the 81 bp variable site located...
Show moreEmerging rise in microbial drug resistance and the slow-growing characteristic of some intracellular pathogens such as MAP (Mycobacterium avium subspecies paratuberculosis) strongly urges the need for an effective approach for unconventional drug susceptibility testing. We designed a molecular-based PCR method for the evaluation of rifabutin (RFB) and rifampicin (RIF) resistance based on probable determinant regions within the rpoB gene of MAP, including the 81 bp variable site located between nucleotides 1363 and 1443. The minimum inhibitory concentration (MIC) for RIF was also determined against 10 MAP isolates in attempt to seek correlation with rpoB sequences. We determined that MAP strain 18 had an MIC > 30 ug/ml and > 5 ug/ml for RIF and RFB respectively, and a significant rpoB mutation C1367T, compared to an MIC of < 1.0 ug/ml for both drugs in the wild type MAP. The 30-fold increase in the MIC was a direct result of the rpoB mutation C1367T, which caused an amino acid change Thr456 to Ile456 in the drug's binding site; the beta subunit of RNA polymerase. Our in vitro induced mutation in MAP strain UCF5 resulted in the generation of a new resistant strain (UCF5-RIF16r) that possessed T1442C rpoB mutation and an MIC > 30 ug/ml and > 10 ug/ml for RIF and RFB respectively. The T1442C mutation resulted in a Leu481 to Pro481 amino acid change, consequently altering the beta subunit sequence. Sequencing the entire 3.5 kb rpoB in strains 18 and UCF5-RIF16r revealed no additional expressed nucleotide mutation. Of the 10 MAP strains analyzed, an additional one strain (UCF4) exhibited a slight increase in the MIC against RIF and RFB compared to the wild-type. Nucleotide sequencing of the rpoB gene revealed an A2284C mutation in strain UCF4 that occurred further downstream of the expected probable rpoB region and resulted in an amino acid alteration Asn762 to His762. The location of this mutation outside the binding site and its correlation with the minor increase in MIC suggests a possible secondary interaction between the drug and the beta subunit. We have provided three dimensional images through the utilization of PyMol Molecular-based Graphics to display a clear comparison of the mutations observed in the beta subunit for MAP strains 18, UCF5-RIF16r, and UCF4. We propose that these alterations may have caused a less stable interaction between RIF and the beta subunit, resulting in the observed increased in MIC. Furthermore, the change in amino acid sequence did not affect the viability for our RIF resistant strains. The data clearly illustrates that clinical and in vitro-induced MAP mutants with rpoB mutations result in resistance to RIF and RFB. Consequently, unconventional drug susceptibility testing such as our molecular approach will be beneficial for evaluation of antibiotic effectiveness. This molecular approach may also serve as a model for other drugs used for treatment of MAP infections.
Show less - Date Issued
- 2007
- Identifier
- CFE0001729, ucf:47310
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001729
- Title
- REAL TIME REVERSE TRANSCRIPTION-POLYMERASE CHAIN REACTION FOR DIRECT DETECTION OF VIABLE MYCOBACTERIUM AVIUM SUBSPECIES PARATUBERCULOSIS IN CROHN'S DISEASE PATIENTSANDASSOCIATION OF MAP INFECTION WITH DOWNREGUALTION IN INTERFERON-GAMMA RECEPTOR (INFG1) GENE IN CROHN'S DISEASE PATIENTS.
- Creator
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Chehtane, Mounir, Naser, Saleh, University of Central Florida
- Abstract / Description
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Association of Mycobacterium avium subspecies paratuberculosis (MAP) with Crohn's disease (CD) and not with ulcerative colitis (UC), two forms of inflammatory bowel disease (IBD), has been vigorously debated in recent years. This theory has been strengthened by recent culture of MAP from breast milk, intestinal tissue and Blood from patients with active Crohn's disease. Culture of MAP from clinical samples remained challenging due to the fastidious nature of MAP including its lack of cell...
Show moreAssociation of Mycobacterium avium subspecies paratuberculosis (MAP) with Crohn's disease (CD) and not with ulcerative colitis (UC), two forms of inflammatory bowel disease (IBD), has been vigorously debated in recent years. This theory has been strengthened by recent culture of MAP from breast milk, intestinal tissue and Blood from patients with active Crohn's disease. Culture of MAP from clinical samples remained challenging due to the fastidious nature of MAP including its lack of cell wall in infected patients. The advent of real time PCR has proven to be significant in infectious disease diagnostics. In this study, real time reverse transcriptase PCR (RT-PCR) assay based on targeting mRNA of the IS900 gene unique to MAP has been developed. All variables included in RNA isolation, cDNA synthesis and real time PCR amplification have been optimized. Oligonucleotide primers were designed to amplify 165 bp specific to MAP and the assay demonstrated sensitivity of 4 genomes per sample. In hope this real time RT-PCR may aid in the detection of viable MAP cells in Crohn's disease patients, a total of 45 clinical samples were analyzed. Portion of each sample was also subjected to 12 weeks culture followed by standard nested PCR analysis. The samples consisted of 17 cultures (originated from 13 CD, 1 UC and 3 NIBD subjects), 24 buffy coat blood (originated from 7 CD, 2 UC, 11 NIBD and 4 healthy subjects) and 4 intestinal biopsies from 2 CD patients. Real time RT-PCR detected viable MAP in 11/17 (65%) of iii suspected cultures compared to 12/17 (70%) by nested PCR including 77% and 84% from CD samples by both methods, respectively. Real time RT-PCR detected MAP RNA directly from 3/7 (42%) CD, 2/2 (100%) UC and 0/4 healthy controls similar to results following long term culture incubation and nested PCR analysis. Interestingly, real time RT-PCR detected viable MAP in 2/11 (13%) compared to 4/11 (26%) by culture and nested PCR in NIBD patients. For tissue samples, real time RT-PCR detected viable MAP in one CD patient with the culture outcome remains pending. This study clearly indicates that a 12-hr real time RT-PCR assay provided data that are similar to those from 12 weeks culture and nested PCR analysis. Consequently, use of real time In our laboratory, we previously demonstrated a possible downregulation in the Interferon-gamma receptor gene (IFNGR1) in patients with active Crohn's disease using microarray chip analysis. In this study, measurement of RNA by real time qRT-PCR indicated a possible downregulation in 5/6 CD patients compared to 0/12 controls. The preliminary data suggest that downregulation in INFGR1 gene, and the detection of viable MAP in CD patients provides yet the strongest evidence toward the linkage between MAP and CD etiology.
Show less - Date Issued
- 2005
- Identifier
- CFE0000629, ucf:46504
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000629
- Title
- POSSIBLE USE OF P20 ANTIGEN IN SERODIAGNOSIS OF INFLAMMATORY BOWEL DISEASE.
- Creator
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Yang, ShinChieh, Naser, Saleh, University of Central Florida
- Abstract / Description
-
Crohn's disease (CD) is an idiopathic, chronic, relapsing inflammatory disorder, which is most commonly involved terminal ileum and colon. The incidence and prevalence of CD has dramatically increased during the last 50 years; however, the etiology and mechanism of this disorder remain unveiled. Besides genetic susceptibility, recent integrated researches investigated the role of environmental triggers such as microflora, measles viruses and mycobacteria in the pathogenesis of CD. The...
Show moreCrohn's disease (CD) is an idiopathic, chronic, relapsing inflammatory disorder, which is most commonly involved terminal ileum and colon. The incidence and prevalence of CD has dramatically increased during the last 50 years; however, the etiology and mechanism of this disorder remain unveiled. Besides genetic susceptibility, recent integrated researches investigated the role of environmental triggers such as microflora, measles viruses and mycobacteria in the pathogenesis of CD. The association between M. avium subsp paratuberculosis (MAP) and CD has been heightened because of clinical resemblance to Johne's disease (JD), a granulomatous enteritis in ruminants caused by MAP. Isolation of MAP from tissue and milk samples from CD patients and from commercial pasteurized milk and dairy products from JD-infected animals implies a possible re-classification of CD as zoonotic disorder. Clinical signs and symptoms of CD are often non-specific and a challenge to distinguish it from other disorders. Current methods for inflammatory bowel disease diagnosis, especially for CD are highly invasive, distressing and expensive. In this study, the recombinant clone pB11 containing 1.1 kb insert, identified from a MAP genomic library constructed in E. coli, expressed a 20 kDa (p20) antigen encoded on 549 bp partial MAP gene with an ORF cloned in frame within pBAD/His cloning vector. Immunoreactivity of p20 was confirmed by Immunoblot. Purified p20 antigen was then used in the development of an enzyme-linked immunosorbent assay (ELISA) for possible serodiagnosis of Inflammatory Bowel Disease (IBD) associated with MAP infection. All variables associated with ELISA test with regard to concentrations, washes and incubations were optimized using hyper immune rabbit t-anti-MAP polyclonal IgG antibodies and sera from CD and non-CD subjects. The cut-off value for positive response was established as 0.3 following the analysis of statistically formulated samples from normal and non-CD subjects. The developed ELISA test was then used to test a blindly coded 2 17 clinical sera. All sera samples were tested in duplicates and in both p20-coated and uncoated micro titer plates. Consequently, 116/134 (87%) CD sera were positive compared to 24/83 (33%) non-CD sera (P<0.05). Specifically anti-MAP IgG was detected in 8/22 (36%) Ulcerative colitis and 16/61 (26%) non-IBD sera. p20-ORF encoding sequence was recloned (pB11/B6) and the expressed protein reactivity remained consistent. Moreover, the full length of the cloned gene was also identified through blast and alignment analysis and predicted to encode 346 amino acids with unknown function and no identity with other known proteins. The latter supports the clinical data, which reflect on the unique characteristics of this antigen. The result so far suggests that the recombinant clone and its subclone derivative may have potential role in serodiagnosis of CD.
Show less - Date Issued
- 2004
- Identifier
- CFE0000089, ucf:46148
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000089
- Title
- EFFECT OF PROPIONIC ACID-DERIVATIVE IBUPROFEN ON NEURAL STEM CALL DIFFERENTIATION; A POTENTIAL LINK TO AUTISM SPECTRUM DISORDER.
- Creator
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Samsam, Aseelia, Naser, Saleh, University of Central Florida
- Abstract / Description
-
Propionic acid (PPA) is a short chain fatty acid that is produced by the human gut microbiome. Propionate, butyrate and acetates are the end products of the fermentation of the complex carbohydrates by human gut friendly microbiome and are being used as sources of energy in our body. PPA is used as a food preservative against molds in various daily products and has been implicated in the pathogenesis of autism. In a recent study we showed that PPA in human neuronal stem cell (NSC) culture...
Show morePropionic acid (PPA) is a short chain fatty acid that is produced by the human gut microbiome. Propionate, butyrate and acetates are the end products of the fermentation of the complex carbohydrates by human gut friendly microbiome and are being used as sources of energy in our body. PPA is used as a food preservative against molds in various daily products and has been implicated in the pathogenesis of autism. In a recent study we showed that PPA in human neuronal stem cell (NSC) culture increases the astrocyte population and decreases the neuronal number and increases the inflammatory cytokines. In this study, we investigated the potential effects of a propionic acid-derivative, Ibuprofen, a member of the non-steroidal anti-inflammatory drugs (NSAIDs) on neural stem cells proliferation and differentiation in vitro. Ibuprofen is an over counter drug that is used for alleviating pain, headache, and fever. To examine the effect of ibuprofen on developing brain we used human NSC in vitro, exposed them to increasing concentrations of ibuprofen, and investigated neural proliferation and differentiation. Here we show that NSAIDs, not at therapeutic, but very high concentrations cause an imbalance in NSC differentiation towards glial cells, therefore causing astrogliosis seen in some cases of autism spectrum disorder (ASD). Furthermore, upon removal of Ibuprofen, inflammatory cytokines; TNF-alpha, IL-6 and IL-10, significantly increase (p
Show less - Date Issued
- 2019
- Identifier
- CFH2000579, ucf:45625
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH2000579
- Title
- SYSTEMATIC REVIEW AND META-ANALYSIS: TUBERCULOSIS, TNFΑ INHIBITORS, AND CROHN'S DISEASE.
- Creator
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Cao, Brent L, Naser, Saleh A., University of Central Florida
- Abstract / Description
-
Inflammation is often a protective reaction against harmful foreign agents. However, in many disease conditions, the mechanisms behind the inflammatory response are poorly understood. Often times, the inflammation causes adverse effects, such as joint pain, abdominal pain, fever, fatigue, and loss of appetite. Thus, many treatments aim to inhibit the inflammatory response in order to control adverse symptoms. Such treatments include TNFα inhibitors. However, a major risk associated with drugs...
Show moreInflammation is often a protective reaction against harmful foreign agents. However, in many disease conditions, the mechanisms behind the inflammatory response are poorly understood. Often times, the inflammation causes adverse effects, such as joint pain, abdominal pain, fever, fatigue, and loss of appetite. Thus, many treatments aim to inhibit the inflammatory response in order to control adverse symptoms. Such treatments include TNFα inhibitors. However, a major risk associated with drugs inhibiting tumor necrosis factor alpha (TNFα) is serious infection, including tuberculosis (TB). Anti-TNFα therapy is used to treat patients with Crohn's disease, for which the risk of tuberculosis may be even more concerning. Recent literature suggests Crohn's might involve Mycobacterium avium subspecies paratuberculosis (MAP), an intracellular TB-like bacterium. This study seeks to investigate the risk of developing TB in patients with Crohn's disease treated with TNFα inhibitors. A meta-analysis synthesized existing evidence. Evidence came from published randomized, double-masked, placebo-controlled trials of TNFα inhibitors for treatment of adult Crohn's disease. Twenty-three trials were identified, including 5,669 patients. The risk of tuberculosis was significantly increased in anti-TNFα treated patients, with a risk difference of 0.028 (95% confidence interval [CI], 0.0011-0.055). The odds ratio was 4.85 (95% CI, 1.02-22.99) when all studies were included and 5.85 (95% CI, 1.13-30.38) when studies reporting zero tuberculosis cases were excluded. The risk of tuberculosis is increased in patients with Crohn's disease treated with TNFα inhibitors. The medical community should be alerted about this risk and the potential for TNFα inhibitor usage favoring granulomatous infections and worsening the patient condition.
Show less - Date Issued
- 2018
- Identifier
- CFH2000360, ucf:45909
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH2000360
- Title
- EXPRESSION AND CHARACTERIZATION OF MYCOBACTERIUM PARATUBERCULOSIS 19KDA WITH POSTTRANSLATIONAL MODIFICATION.
- Creator
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Safavi-Khasraghi, Mitra, Naser, Saleh, University of Central Florida
- Abstract / Description
-
Despite the fact that E. coli supports limited posttranslational modification, this bacterium has been universally used as the expression system of choice. Expression of modified proteins in E. coli may lead to expression of recombinant proteins that lack essential immunomodulatory or catalytic components essentials for infectious processes. Previously in our laboratory, pMptb#28 plasmid containing a 4.8 kb insert from M. paratuberculosis has been identified which expressed 16 kDa recombinant...
Show moreDespite the fact that E. coli supports limited posttranslational modification, this bacterium has been universally used as the expression system of choice. Expression of modified proteins in E. coli may lead to expression of recombinant proteins that lack essential immunomodulatory or catalytic components essentials for infectious processes. Previously in our laboratory, pMptb#28 plasmid containing a 4.8 kb insert from M. paratuberculosis has been identified which expressed 16 kDa recombinant protein in E. coli and 19 kDa recombinant protein in Mycobacterium smegmatis. The objective of this study is to identify the ORF sequence, investigate possible posttranslational modification and characterize the protein forms in the two hosts. Earlier in the study, the genome sequence for M. paratuberculosis was not available and therefore sequencing both the 5' and 3' ends of the 4.8 kb insert did not help in the identification of the ORF. However, unidirectional Exonuclease deletion resulted in identification of subclones containing possible ORF sequence. Later on, the publication of the M. paratuberculosis genome sequence along with BLAST analysis of sequences from the subclones resulted in the identification of 486 bp ORF with significant identity to that from M. tuberculosis and M. leprae. Cloning of the 486 ORF coding sequence in E. coli resulted in the expression of 16 kDa protein similar to the calculated predicted size of translated peptide. Cloning of the 486 bp ORF coding sequence in M. smegmatis resulted in the expression of 19 kDa protein similar to that from M. paratuberculosis. The 16/19 kDa forms of the same protein were verified using rabbit anti-M. paratuberculosis antibodies adsorbed in E. coli and M. smegmatis lysates. The size of the 19 kDa proteins was not reduced following treatment with deglycosylation enzymes in absence of any enzyme inhibitors. The 19 kDa product was confirmed not be a glycoprotein when failed to react with ConA stain. The 16/19 kDa forms of the protein were evaluated against T-lymphocytes from Crohn's disease patients and normal controls. T- proliferation assay included controls such as PHA and PPD from M. paratuberculosis. There was not a significant difference between the two forms of the protein (16/19 kDa) against T-cell response from both populations. Overall, the study identified the ORF of the 19 kDa non-glycoprotein from M. paratuberculosis. Moreover, this is the first study which reports that the zoonotic M. paratuberculosis supports posttranslational modification similar to M. tuberculosis and M. leprae pathogens. Although the posttranslational modification component in this 19 kDa nonglycoprotein did not affect T- cell response, the finding is significant toward glycoproteins from M. paratuberculosis and their role in the pathogenesis of this bacterial infection in animals and humans.
Show less - Date Issued
- 2006
- Identifier
- CFE0001170, ucf:52851
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001170
- Title
- SURVIVAL OF MYCOBACTERIUM AVIUM SUBSPECIES PARATUBERCULOSIS IN THE POLYMORPHONUCLEAR LEUKOCYTES OF A CROHN'S DISEASE PATIENT.
- Creator
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Rumsey, John, Naser, Saleh, University of Central Florida
- Abstract / Description
-
Mycobacterium avium subspecies paratuberculosis (map) is an intracellular pathogen that is known to parasitize macrophages and monocytes. Map infiltrates gastrointestinal tract host tissue where it is the known etiological agent of johne's disease in ruminants and implicated in the etiology of crohn's disease in humans. Map's ability to survive within macrophages enables it to disseminate throughout the rest of the host, possibly infecting other circulating blood leukocytes. In this study,...
Show moreMycobacterium avium subspecies paratuberculosis (map) is an intracellular pathogen that is known to parasitize macrophages and monocytes. Map infiltrates gastrointestinal tract host tissue where it is the known etiological agent of johne's disease in ruminants and implicated in the etiology of crohn's disease in humans. Map's ability to survive within macrophages enables it to disseminate throughout the rest of the host, possibly infecting other circulating blood leukocytes. In this study, the survival and fate of map strain atcc 43015 (human isolate) following phagocytosis was determined using in vitro murine macrophage cell line j774a.1 and polymorphonuclear cells (pmnc's) from five crohn's disease patients. Pmnc's from three healthy individuals and two ulcerative colitis patients, as well as escherichia coli (atcc 11303) and mycobacterium tuberculosis strain h37ra (atcc 25177), were included as controls (moi 10:1). Maturation of the phagosome was determined by evaluating the presence of stage specific markers on the surface of the phagosomal membrane. The endosomal protein, transferrin receptor, and the lysosomal marker, lamp-1, were then immunostained with cy-5 conjugated secondary antibodies, and colocalization of bacteria with each marker was evaluated separately using confocal scanning laser microscopy (cslm). In both tissue models, colocalization of viable map and m. Tuberculosis with the early endosomal marker, transferrin receptor occurred with an estimated five fold higher frequency than did association with the late lysosomal marker, lamp-1, as compared to live e. Coli, and all dead bacterial species. Using differential live/dead staining and fluorescent microscopy, survival of m. Tuberculosis and map was estimated at 85% and 79%, respectively compared to only 14% for e. Coli. The outcome was similar for both tissue culture and pmncs from all patients tested, suggesting that map and m. Tuberculosis can survive readily in both cell types, and regardless of the disease state of the host or the killing power of the cell. Map's survival appears to mimic m. Tuberculosis', suggesting the ability to resist phagolysosome fusion, by maintaining association with the early endosomes. Overall, the data confirms map virulence in host human blood leukocytes.
Show less - Date Issued
- 2004
- Identifier
- CFE0000184, ucf:52838
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000184
- Title
- Malondialdehyde (MDA) and Glutathione Peroxidase (GPx) are elevated in Crohns disease-associated with Mycobacterium avium subspecies paratuberculosis (MAP).
- Creator
-
Qasem, Ahmad, Naser, Saleh, Masternak, Michal, Parthasarathy, Sampath, Andl, Claudia, University of Central Florida
- Abstract / Description
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Inflamed tissue in Crohn's disease (CD) are continuously producing toxic oxygen metabolites leading to cellular injury and apoptosis. Here, we are evaluating the role of Mycobacterium avium subspecies paratuberculosis (MAP) in oxidative stress in CD by evaluation of lipid peroxidation and antioxidant defense activity. Specifically, we measured malondialdehyde (MDA) level and selenium-dependent glutathione peroxidase (GPx) activity in the plasma from patients and cattle infected with MAP. The...
Show moreInflamed tissue in Crohn's disease (CD) are continuously producing toxic oxygen metabolites leading to cellular injury and apoptosis. Here, we are evaluating the role of Mycobacterium avium subspecies paratuberculosis (MAP) in oxidative stress in CD by evaluation of lipid peroxidation and antioxidant defense activity. Specifically, we measured malondialdehyde (MDA) level and selenium-dependent glutathione peroxidase (GPx) activity in the plasma from patients and cattle infected with MAP. The level of MAP antibodies in bovine sera was determined by IDEXX kit whereas detection of MAP DNA was performed by IS900-based nPCR. A total of 42 cattle (21 infected with MAP and 21 healthy controls), 27 CD subjects, 27 of CD-healthy relatives, 66 subjects with various diseases and 34 non-related healthy subjects were investigated. Overall, GPx activity was significantly higher in MAP infected humans (0.80941(&)#177;0.521) versus MAP (-ve) samples (0.42367(&)#177;0.229 units/ml), P(<)0.01. Similarly, the average of GPx activity in cattle infected with MAP was 1.59(&)#177;0.65 units/ml compared to 0.46907(&)#177;0.28 units/ml in healthy cattle (P(<)0.01). Although it was not statistically significant, MDA average level was higher in MAP infected human samples versus MAP (-ve) controls (1.11(&)#177;0.185 nmol/ml versus 0.805(&)#177;0.151 nmol/ml, respectively). Similarly, MDA average level in CD samples that are MAP+ (1.703(&)#177;0.231 nmol/ml) was higher than CD samples that are MAP (-ve) (1.429(&)#177;0.187 nmol/ml). In cattle, MDA average level in MAP infected samples was significantly higher at 3.818(&)#177;0.45 nmol/ml compared to 0.538(&)#177;0.18 nmol/ml in healthy cattle (P(<)0.01). Clearly, the data demonstrated that MAP infection is associated with oxidative stress and resulting in the pathophysiology of worsening of the condition of CD patients.
Show less - Date Issued
- 2016
- Identifier
- CFE0006699, ucf:51906
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006699
- Title
- Role of Single Nucleotide Polymorphisms (SNPs) in PTPN2/22 and Mycobacterium avium subspecies paratuberculosis (MAP) in Rheumatoid Arthritis and Crohn's Disease.
- Creator
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Sharp, Robert, Naser, Saleh, Parks, Griffith, Roy, Herve, Singla, Dinender, University of Central Florida
- Abstract / Description
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Both genetic pre-disposition and potential environmental triggers are shared between Rheumatoid arthritis (RA) and Crohn's disease (CD). We hypothesized that single nucleotide polymorphisms (SNPs) in the negative T-cell regulators Protein Tyrosine Phosphatase Non-receptor type 2 and 22 (PTPN2/22) lead to a dysregulated immune response as seen in RA and CD. To test the hypothesis, peripheral leukocytes samples from 204 consented subjects were TaqMan genotyped for 9 SNPs in PTPN2/22. The SNPs...
Show moreBoth genetic pre-disposition and potential environmental triggers are shared between Rheumatoid arthritis (RA) and Crohn's disease (CD). We hypothesized that single nucleotide polymorphisms (SNPs) in the negative T-cell regulators Protein Tyrosine Phosphatase Non-receptor type 2 and 22 (PTPN2/22) lead to a dysregulated immune response as seen in RA and CD. To test the hypothesis, peripheral leukocytes samples from 204 consented subjects were TaqMan genotyped for 9 SNPs in PTPN2/22. The SNPs effect on PTPN2/22 and IFN-y expression was determined using RT-PCR. Blood samples were analyzed for the Mycobacterium avium subspecies paratuberculosis (MAP) IS900 gene by nPCR. T-cell proliferation and response to phytohematoagglutonin (PHA) mitogen and MAP cell lysate were determined by BrdU proliferation assay. Out of 9 SNPs, SNP alleles of PTPN2:rs478582 occurred in 79% RA compared to 60% control (p-values ? 0.05). SNP alleles of PTPN22:rs2476601 occurred in 29% RA compared to 6% control (p-values ? 0.05). For the haplotype combination of PTPN2:rs478582/PTPN22rs2476601, 21.4% RA had both SNPs (C-A) compared to 2.4% control (p-values ? 0.05). PTPN2/22 expression in RA was decreased by an average of 1.2 fold. PTPN2:rs478582 upregulated IFN-y in RA by an average of 1.5 fold. Combined PTPN2:rs478582/PTPN22:rs2476601 increased T-cell proliferation by an average of 2.7 fold when treated with PHA. MAP DNA was detected in 34% RA compared to 8% controls (p-values ? 0.05), where samples with PTPN2:rs478582 and/or PTPN22:rs2476601 were more MAP positive. PTPN2:rs478582/PTPN22:rs2476601 together with MAP infection significantly increased T-cell response and IFN-y expression in RA samples. The same experimental approach was followed on blood samples from CD patients. Both PTPN2:rs478582/PTPN22:rs2476601 affected PTPN2/22 and IFN-y expression along with T-cell proliferation significantly more than in RA. MAP DNA was detected in 64% of CD. This is the first study to report the correlation between SNPs in PTPN2/22, IFN-y expression and MAP in autoimmune disease.
Show less - Date Issued
- 2018
- Identifier
- CFE0007371, ucf:52094
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007371
- Title
- Role of Lipid Peroxide Derived Dicarboxylic Acids in Atherosclerotic Calcification.
- Creator
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Riad, Aladdin, Parthasarathy, Sampath, Altomare, Deborah, Masternak, Michal, Naser, Saleh, University of Central Florida
- Abstract / Description
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Cardiovascular diseases, including atherosclerosis, are the leading cause of death in the United States. Atherosclerotic lesions are formed by deposition of lipids in the intima of arteries. Upon exposure to oxidative stresses, low-density lipoprotein (LDL) is converted to highly atherogenic oxidized LDL (ox-LDL) particles, contributing to disease development and progression. Advanced disease stages may result in calcification of lesions. This calcification process is important, as it has...
Show moreCardiovascular diseases, including atherosclerosis, are the leading cause of death in the United States. Atherosclerotic lesions are formed by deposition of lipids in the intima of arteries. Upon exposure to oxidative stresses, low-density lipoprotein (LDL) is converted to highly atherogenic oxidized LDL (ox-LDL) particles, contributing to disease development and progression. Advanced disease stages may result in calcification of lesions. This calcification process is important, as it has been shown to be associated with stable plaques that are less prone to rupture. Calcification is present in lipid rich domains of lesions, however neither the composition of the mineralized calcium deposits nor its relationship to lipid peroxidation or the lipid rich atherosclerotic core has previously been identified. This study provides evidence that the lipid peroxide derived dicarboxylic acid (DCA), azelaic acid (AzA) induces calcification in smooth muscle cells, thereby providing the link between calcification and overall plaque burden, and association of calcification with the lipophilic region of the lesion. The potential of lipid peroxide-derived lipophilic DCAs to promote calcification upon exposure to vascular smooth muscle cells was tested. 13-hydroperoxylinoleic acid (HPODE) treatment resulted in the cellular conversion to 9-oxononanoic acid (ONA) and AzA as determined by mass spectrometry analysis. Delivery of AzA via lysophosphatidylcholine (Lyso-PtdCho) micelles induced calcification of human aortic smooth muscle cells (HASMC). AzA was identified in calcified human and mouse atherosclerotic plaques. Calcification of HASMC due to AzA treatment resulted in a less inflammatory and oxidative environment as indicated by genetic expression. These results demonstrate that DCAs may contribute to atherosclerotic calcification thus accounting for the latter's relationship to plaque burden and association with lipids. This study also challenges the dogma that arterial calcification represents the deposition of calcium phosphate and has implications with the development of new therapeutic strategies in treating late stage atherosclerosis.
Show less - Date Issued
- 2018
- Identifier
- CFE0007413, ucf:52730
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007413
- Title
- Determining differential effects of Interleukin-2 on innate and adaptive immune cells in lymphoid organs and the gastrointestinal Tract.
- Creator
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Singh, Ayushi, McKinstry, Karl, Naser, Saleh, Copik, Alicja, University of Central Florida
- Abstract / Description
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Interleukin-2 (IL-2) is a pleiotropic cytokine demonstrated to be effective in treating cancer. However, the clinical use of IL-2 can be associated with severe side effects including gastrointestinal toxicity (GT). Similar GT symptoms are observed in inflammatory diseases such as CD (CD). Interestingly mounting evidence indicates a role for IL-2 in CD, but the underlying mechanisms are unknown. Indeed, studies on the in-vivo activities of IL-2 have mostly focused on secondary lymphoid organs...
Show moreInterleukin-2 (IL-2) is a pleiotropic cytokine demonstrated to be effective in treating cancer. However, the clinical use of IL-2 can be associated with severe side effects including gastrointestinal toxicity (GT). Similar GT symptoms are observed in inflammatory diseases such as CD (CD). Interestingly mounting evidence indicates a role for IL-2 in CD, but the underlying mechanisms are unknown. Indeed, studies on the in-vivo activities of IL-2 have mostly focused on secondary lymphoid organs and immune cells associated with them. Very few studies have addressed how IL-2 signals impact populations of immune cells in the gut. Here, we aim to identify and compare the effects of systemic IL-2 administration on six major leukocyte population and their subsets in mice using multicolor flow cytometry. While we confirmed previously observed changes in specific immune cell populations in the spleen, very few changes were seen in the gut and gut associated lymphoid tissues. Unexpectedly, a sharp decline was seen in B cells, most notably in Peyer's Patches, in mice treated with IL-2. Our data furthermore indicates that B cells in IL-2 treated mice undergo enhanced apoptosis in Peyer's Patches. Some studies suggest that changes in B cells may contribute to development of CD. Thus, this study may aid in defining ways in which IL-2 can contribute to disease etiology, and lead to novel treatments for CD.
Show less - Date Issued
- 2019
- Identifier
- CFE0007865, ucf:52777
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007865
- Title
- VO-OHpic Treatment Reduces Cardiac Remodeling in Doxorubicin-Induced Cardiomyopathy.
- Creator
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Johnson, Taylor, Singla, Dinender, Parthasarathy, Sampath, Naser, Saleh, University of Central Florida
- Abstract / Description
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Doxorubicin (Doxo) is one of multiple anthracycline drugs used to effectively treat various forms of cancer. Unfortunately, Doxo treatment, as a side effect, induces cardiomyopathy and subsequent heart failure. We have previously demonstrated that transplanted embryonic stem (ES) cells and their conditioned medium (CM) modulate the PTEN pathway and reduce apoptosis, fibrosis and hypertrophy in a Doxo induced cardiomyopathy (DIC) model. However, mechanisms of inhibited apoptosis mediated...
Show moreDoxorubicin (Doxo) is one of multiple anthracycline drugs used to effectively treat various forms of cancer. Unfortunately, Doxo treatment, as a side effect, induces cardiomyopathy and subsequent heart failure. We have previously demonstrated that transplanted embryonic stem (ES) cells and their conditioned medium (CM) modulate the PTEN pathway and reduce apoptosis, fibrosis and hypertrophy in a Doxo induced cardiomyopathy (DIC) model. However, mechanisms of inhibited apoptosis mediated through PTEN pathway are completely unknown. Therefore, we used VO-OHpic (VO), a potent PTEN inhibitor to understand the mechanism of apoptosis as well as its effect on cardiac remodeling in DIC. Animals were divided into three groups; Group 1: Control (Saline), Group 2: Doxo (12 mg/kg, cumulative dose) and Group 3: Doxo+VO (30ug/kg cumulative dose). Animals were studied at one week and eight weeks post-DIC. Mice were subjected to echocardiography to examine cardiac function, sacrificed and hearts were harvested for further analysis. Immunohistochemistry staining revealed a significant (p (<) 0.05) decrease in apoptotic cardiomyocytes in Doxo+VO treated hearts compared with Doxo group. Furthermore, Hematoxylin and Eosin (H(&)E) and Masson's Trichrome histological stains confirmed reduced hypertrophy and fibrosis in Doxo+VO treated subjects compared to Doxo group. Western Blotting confirmed the reduction of p-PTEN levels and the increase in p-AKT cell survival protein expression in Doxo+VO subjects. In addition, VO-OHpic administration was shown to reduce the number of pro-inflammatory macrophages and increase the number of anti-inflammatory M2 macrophages that may further be involved in reduced apoptosis and fibrosis. Finally, heart function was improved in mice treated with VO compared to Doxo group. Collectively, our data suggests that VO-OHpic treatment reduces apoptosis, cardiac fibrosis and the process is mediated through the PTEN/AKT and inflammatory mechanisms with improved heart function in the DIC heart.
Show less - Date Issued
- 2016
- Identifier
- CFE0006690, ucf:51924
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006690
- Title
- Downregulation in IFNGR1 increases suspectiblity to Mycobacterium avium subspecies paratuberculosis infection in Crohn's disease.
- Creator
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Htun, Zin Mar, Naser, Saleh, Andl, Claudia, Tigno-Aranjuez, Justine, University of Central Florida
- Abstract / Description
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BACKGROUND: Crohn's disease (CD) is an inflammatory bowel disease (IBD) and has been associated with Mycobacterium avium subspecies paratuberculosis (MAP). MAP has been detected in stool, tissue and blood samples from patients with CD. Gamma interferon (?-IFN) is an inflammatory cytokine that plays a crucial role in killing intracellular pathogens like MAP, and its receptor (IFNGR1) mutations cause immunodeficiency and severe disseminated mycobacterial infections. The role of MAP in...
Show moreBACKGROUND: Crohn's disease (CD) is an inflammatory bowel disease (IBD) and has been associated with Mycobacterium avium subspecies paratuberculosis (MAP). MAP has been detected in stool, tissue and blood samples from patients with CD. Gamma interferon (?-IFN) is an inflammatory cytokine that plays a crucial role in killing intracellular pathogens like MAP, and its receptor (IFNGR1) mutations cause immunodeficiency and severe disseminated mycobacterial infections. The role of MAP in association with IFNGR1 mutation in CD patients have not been investigated.METHODS: In this study, we investigated blood samples of 79 human subjects for MAP infection in association with IFNGR1 gene dysfunction. Samples were divided into 22 CD, 6 Ulcerative colitis (UC), 32 normal healthy and 19 non-inflammatory bowel disease (NIBD). Five variants of IFNGR1 single nucleotide polymorphisms (SNP) were investigated using Taqman Genotyping assay, then IFNGR1 expression measured by RT-PCR and serum IFNGR1 and ?-IFN levels were measured using ELISA. MAP infection was detected using nested PCR. RESULTS: Among 28 IBD patients, 4/6 (66.67%) of UC and 18/22 (81.82%) of CD are tested positive for at least one SNP homozygous minor form compared to 21.88% and 47.37%% in 32 healthy and 19 NIBD (P (<)0.05). IFNGR1 gene expression was downregulated 1.4-fold in IBD patients (P =0.07) and 1.7-fold downregulated in MAP positive IBD patients compared to MAP negative IBD patients (P=0.06). Serum IFNGR1 protein levels were downregulated 1.53-fold in IBD patients compared to normal, and 1.4-fold downregulated in MAP positive IBD patients compared to MAP negative IBD patients. MAP infection is more common in rs2234711 SNP positive patients (5/7 =71.42%) (P(<)0.05). Serum ?-IFN levels were not elevated in both groups.CONCLUSION: IFNGR1 SNP's, MAP infection and IFNGR1 downregulation were found in higher incidence in IBD, suggesting role of IFNGR1 in susceptibility of MAP infection in IBD patients.
Show less - Date Issued
- 2017
- Identifier
- CFE0007121, ucf:51951
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007121
- Title
- Apolipoprotein-AI Regulates Hepatic VLDL Secretion by Controlling Intracellular VLDL-Trafficking.
- Creator
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Gurwani, Bhavesh, Siddiqi, Shadab, Masternak, Michal, Naser, Saleh, University of Central Florida
- Abstract / Description
-
Cardiovascular diseases cause 17 million deaths annually, which is estimated to increase to 23 million deaths by the year 2030. One of the major risk factors for the pathogenesis of cardiovascular diseases is increased secretion of very-low density lipoproteins (VLDL) by the liver; however, reduced VLDL-secretion causes fatty liver disease. Synthesis and secretion of VLDL by the liver plays an important role in maintaining overall lipoprotein homeostasis. Assembly of VLDL occurs along with...
Show moreCardiovascular diseases cause 17 million deaths annually, which is estimated to increase to 23 million deaths by the year 2030. One of the major risk factors for the pathogenesis of cardiovascular diseases is increased secretion of very-low density lipoproteins (VLDL) by the liver; however, reduced VLDL-secretion causes fatty liver disease. Synthesis and secretion of VLDL by the liver plays an important role in maintaining overall lipoprotein homeostasis. Assembly of VLDL occurs along with the expression of apolipoproteinB-100 (apoB100) and its lipidation at the endoplasmic reticulum (ER) level. Once formed in the ER lumen, the nascent VLDL is transported to the Golgi for its maturation. In the Golgi compartment, the nascent VLDL acquires apolipoproteinAI (apoAI), more triglycerides, and its apoB100 undergoes phosphorylation and glycosylation. These modifications are necessary for VLDL-exit from the trans-Golgi network (TGN) and this step is mediated by post-Golgi VLDL transport vesicle (PG-VTV). The transport of mature VLDL from the TGN to the plasma membrane (PM) is required for its secretion by the liver but remains to be studied. Our group has shown that the nascent VLDL particles do not contain apoAI, however, VLDL acquires apoAI in the cis-Golgi compartment. Interestingly, apoAI comes off the VLDL as soon as VLDL is secreted into the blood. We hypothesised that apoAI plays an important role in post-TGN VLDL trafficking and thus controls VLDL secretion by the liver. To determine the role of apoAI in the formation of PG-VTV and VLDL secretion, we knocked down apoAI in the hepatocytes using apoAI specific siRNA. The deficiency of apoAI did not have any effect on the expression of apoB100 and other apolipoprotein synthesis that are involved in VLDL synthesis; however, VLDL secretion was significantly reduced. Next, we overexpressed apoAI using plasmid with apoAI gene sequence and checked for the effects in VLDL secretion from the hepatocytes. We observed a significant increase in VLDL secretion from apoAI-overexpressing hepatocytes which is consistent with knockdown results. To determine the role of apoAI in post-TGN trafficking of the mature VLDLs, we isolated sub-cellular organelles from apoAI knockout (apoAI KO) and control mice. Subsequently, we performed in vitro PG-VTV budding assays to assess the effect of apoAI silencing on PG-VTV formation from the TGN. Our results strongly suggest that the deficiency of apoAI increases PG-VTV formation (i.e. TGN-exit of mature VLDL) but significantly reduces VLDL-triglyceride secretion from the hepatocytes. We conclude that apoAI controls VLDL secretion by the liver by regulating post-TGN trafficking of mature VLDL.
Show less - Date Issued
- 2016
- Identifier
- CFE0006685, ucf:51908
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006685
- Title
- Role of Mycobacterium avium paratuberculosis (MAP) and TNFSF15 SNPs on TL1A in CD.
- Creator
-
Hassouneh, Sayf Al-Deen, Naser, Saleh, Yooseph, Shibu, Parthasarathy, Sampath, University of Central Florida
- Abstract / Description
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Tumor Necrosis Factor-Like Ligand 1a (TL1A) is a cytokine encoded by Tumor Necrosis Factor Super Family 15 gene (TNFSF15) gene mostly in endothelial cells which binds to T-cells and foments the production of pro-inflammatory cytokines including TNF-?, IL-6, IL-1b, IFN- ? and IL-13. TL1A level is elevated in inflammatory diseases including Crohn's Disease (CD). Although Single Nucleotide Polymorphisms (SNPs) in TNFSF15 have been reported in CD, no studies have investigated the effect of these...
Show moreTumor Necrosis Factor-Like Ligand 1a (TL1A) is a cytokine encoded by Tumor Necrosis Factor Super Family 15 gene (TNFSF15) gene mostly in endothelial cells which binds to T-cells and foments the production of pro-inflammatory cytokines including TNF-?, IL-6, IL-1b, IFN- ? and IL-13. TL1A level is elevated in inflammatory diseases including Crohn's Disease (CD). Although Single Nucleotide Polymorphisms (SNPs) in TNFSF15 have been reported in CD, no studies have investigated the effect of these SNPs on TL1A, inflammation, and susceptibility to Mycobacterium avium subspecies paratuberculosis (MAP) infection. MAP is a strong candidate in CD pathogenesis. This study is designed to elucidate the combined effect of MAP and SNPs in TNFSF15 (rs4263839, rs7848647, rs6478108, or rs6478109) on TL1A secretion and downstream effect on pro-inflammatory cytokines. Peripheral blood from CD and healthy subjects was analyzed for MAP DNA, TNFSF15 genotyping, circulating TL1A level, and IFN- ? and TNF-? gene expression. Our data is first to report that rs4263839, rs7848647, rs6478108, and rs6478109 in TNFSF15 resulted in increase in circulating TL1A level in healthy and CD samples. Specifically, in CD samples with rs7848647, the average TL1A level was 146.9 pg/mL (&)#177; 124.5 compared 62.4 pg/mL (&)#177; 82.8 in normal samples. Similarly, TL1A level in CD samples with rs6478109 was 141.9 pg/mL (&)#177; 127.7 compared to 71.5 pg/mL (&)#177; 88.4 in normal samples (p(<)0.05). All 4 SNPs resulted in significant elevation in TL1A level in healthy samples (p(<)0.05). Moreover, IFN-? expression was significantly higher, by approximately 1.6-fold in CD patients with SNPs relative to CD patients with no SNPs (p(<)0.05). Interestingly, SNPs in TNFS15 had no significant effect on TNF-? expression. MAP was detected in the blood of 63% of CD compared to 6% healthy subjects (p(<).001). The data did not support a correlation between MAP presence and circulating TL1A levels, and no correlation between SNPs in TNSF15 and MAP susceptibility. This study strongly suggests, that SNPs in TNFSF15 increase TL1A levels and may be a contributory factor to the inflammation experienced by CD patients. Over all, the study emphasizes the need for a pharmacogenomic approach in treatment delivery for patients with CD by using TNFSF15 SNPs to identify patients that would benefit from biologics targeting TL1A rather than TNF-? for more efficacious treatment regiments for CD patients.
Show less - Date Issued
- 2018
- Identifier
- CFE0007189, ucf:52263
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007189
- Title
- Development of a Non-Human Primate Model for Staphylococcus aureus Nasal Carriage.
- Creator
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Lasseter, Amanda, Cole, Amy, Naser, Saleh, Teter, Kenneth, University of Central Florida
- Abstract / Description
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Staphylococcus aureus nasal carriage (SANC) is largely asymptomatic, but presents a risk of autoinfection and dissemination to new immunocompromised hosts. SA disease states range from mild cutaneous infections to life-threatening bacteremia. Historically utilized rodent models do not naturally carry SA in the nose, are insufficient in longitudinal SANC experimentation, and lack immune factors that are vital in human clearance of SA. The nasal passages of non-human primates are similar...
Show moreStaphylococcus aureus nasal carriage (SANC) is largely asymptomatic, but presents a risk of autoinfection and dissemination to new immunocompromised hosts. SA disease states range from mild cutaneous infections to life-threatening bacteremia. Historically utilized rodent models do not naturally carry SA in the nose, are insufficient in longitudinal SANC experimentation, and lack immune factors that are vital in human clearance of SA. The nasal passages of non-human primates are similar anatomically and histologically, and reproductive mucosal studies have shown similar immune responses to pathogens and human-relevant microbial profiles. Seventeen captive pigtailed macaques (Macaca nemestrina) were found to naturally carry SA in the nose and pharynx, while topical mupirocin ointment effectively decolonized SA, similar to humans. Colonization was established with a human-relevant inoculum of 104 SA CFUs per nostril in four independent experiments, including with a human isolate (ST398). Autologous and non-autologous macaque strains were carried similarly in load and duration, each surviving over 40 days. Animals that cleared SA showed a rapid neutrophilic innate response, with up-regulation of IL-8, MCP-1, and IL-1? following inoculation, as observed in human hosts. Assessment of the nasal microbiome of pigtailed macaques and humans demonstrated similar relative abundance of the most prevalent genera: Staphylococcus, Corynebacterium, and Acinetobacter. Collectively, these multidimensional analyses provide evidence that the pigtailed macaque is a novel physiological model of human SANC that may be useful for testing novel SA decolonization strategies.
Show less - Date Issued
- 2018
- Identifier
- CFE0007216, ucf:52236
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007216
- Title
- AB Toxins: Recovery from Intoxication and Relative Potencies.
- Creator
-
Cherubin, Patrick, Teter, Kenneth, Naser, Saleh, Jewett, Travis, Zervos, Antonis, University of Central Florida
- Abstract / Description
-
AB-type protein toxins have a catalytic A subunit attached to a cell-binding B subunit. Ricin, Shiga toxin (Stx), exotoxin A, and diphtheria toxin are AB toxins that act within the host cytosol and kill the host cell through pathways involving the inhibition of protein synthesis. Our overall goal is to help elucidate the cellular basis of intoxication for therapeutic development. According to the current model of intoxication, the effect of AB toxins is irreversible. To test this model, we...
Show moreAB-type protein toxins have a catalytic A subunit attached to a cell-binding B subunit. Ricin, Shiga toxin (Stx), exotoxin A, and diphtheria toxin are AB toxins that act within the host cytosol and kill the host cell through pathways involving the inhibition of protein synthesis. Our overall goal is to help elucidate the cellular basis of intoxication for therapeutic development. According to the current model of intoxication, the effect of AB toxins is irreversible. To test this model, we developed a system that uses flow cytometry and a fluorescent reporter to examine the cellular potency of toxins that inhibit protein synthesis. Our data show that cells can recover from intoxication: cells with a partial loss of protein synthesis will, upon removal of the toxin, increase the level of protein production and survive the toxin exposure. This work challenges the prevailing model of intoxication by suggesting ongoing toxin delivery to the cytosol is required to maintain the inhibition of protein synthesis and ultimately cause apoptosis. We also used our system to examine the basis for the greater cellular potency of Stx1 in comparison to Stx2. We found that cells intoxicated with Stx1a behave differently than those intoxicated with Stx2: cells exposed to Stx1a exhibited a population-wide loss of protein synthesis, while cells exposed to Stx2a or Stx2c exhibited a dose-dependent bimodal response in which one subpopulation of cells was unaffected (i.e., no loss of protein synthesis). Additional experiments indicated the identity of the Stx B subunit is a major factor in determining the uniform vs. bimodal response to Stx subtypes. This work provides evidence explaining, in part, the differential toxicity between Stx1 and Stx2. Overall, our collective observations provide experimental support for the development of inhibitors and post-exposure therapeutics that restrict, but not necessarily block, toxin delivery to the host cell.
Show less - Date Issued
- 2019
- Identifier
- CFE0007613, ucf:52523
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007613
- Title
- TRANSPLANTATION OF PLURIPOTENT STEM CELLS CONFERS CARDIAC PROTECTION IN DOX-INDUCED HEART FAILURE THROUGH NOTCH-1 PATHWAY.
- Creator
-
Merino-Chavez, Hilda, Singla, Dinender, Zervos, Antonis, Naser, Saleh, University of Central Florida
- Abstract / Description
-
Doxorubicin (DOX) is the antineoplastic drug of preference used to treat a wide variety of malignancies, with high survival rates among treated patients. However, the benefits of this drug have become less appealing due to the side effects that occur such as DOX-induced cardiomyopathy (DIC) and an increased risk of myocardial infarction (MI). Therefore, there is an urgent need to explore the therapeutic options to treat DIC. In this context, adult stem cells have been used as a source to...
Show moreDoxorubicin (DOX) is the antineoplastic drug of preference used to treat a wide variety of malignancies, with high survival rates among treated patients. However, the benefits of this drug have become less appealing due to the side effects that occur such as DOX-induced cardiomyopathy (DIC) and an increased risk of myocardial infarction (MI). Therefore, there is an urgent need to explore the therapeutic options to treat DIC. In this context, adult stem cells have been used as a source to reduce cardiomyocyte apoptosis in DIC; however, the effects of transplanted embryonic stem (ES) cells and induced pluripotent stem (iPS) cells in DIC post MI are unknown. As a result, we wanted to understand how transplanted ES and iPS cells and the factors released by them inhibit apoptosis and improve cardiac function in DIC post MI. C57BL/6 mice were divided into five groups: Sham, DOX-MI, DOX-MI+cell culture (CC) media, DOX-MI+ES cells, and DOX-MI+iPS cells. Mice were treated with DOX (12 mg/kg, cumulative dose) followed by left coronary artery ligation to induce MI. ES or iPS cells (5 x 104) were delivered into the peri-infarct region. At day 14 post-MI, echocardiography was performed, mice sacrificed, and hearts harvested for further analyses. To investigate if protective effects are provided by factors released from ES and iPS cells in DIC, we performed in vitro studies using condition media (CM) obtained from ES or iPS cells to treat DOX-induced cardiotoxicity in H9c2 cells. Our data reveal that apoptosis was significantly inhibited in the ES and iPS cell transplanted hearts as well as ESCM and iPSCM treated cells compared with the untreated controls. Furthermore, a significant increase in levels of Notch-1, Hes1, and pAkt survival protein were observed. Decreased levels of PTEN, a negative regulator of Akt pathway, along with improved heart function were also observed in the stem cell transplanted groups. In conclusion, our data show that transplantation of ES and iPS cells blunt DOX-induced apoptosis in vivo, which is associated with improved cardiac function. Moreover, decreased apoptosis in both in vitro and in vivo models is mediated by the Notch pathway.
Show less - Date Issued
- 2012
- Identifier
- CFE0004577, ucf:49213
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004577