Current Search: Khaled, Annette (x)
View All Items
Pages
- Title
- IDENTIFICATION OF EPITHELIAL STROMAL INTERACTION 1 AND EPIDERMAL GROWTH FACTOR RECEPTOR AS NOVEL KR(&)#220;PPEL-LIKE FACTOR 8 TARGETS IN PROMOTING BREAST CANCER PROGRESSION.
- Creator
-
Li, Tianshu, Zhao, Jihe, Khaled, Annette, Altomare, Deborah, Lambert, Stephen, University of Central Florida
- Abstract / Description
-
Breast cancer is the major cause of cancer death among women worldwide. Understanding the mechanisms underlying breast cancer progression remains urgent for developing effective treatment strategies to eliminate breast cancer mortality. Our recent studies have demonstrated that Kr(&)#252;ppel-like transcriptional factor 8 (KLF8) plays a critical role for breast cancer progression. Other studies have shown that Epithelial stromal interaction 1 (EPSTI1), a recently identified stromal fibroblast...
Show moreBreast cancer is the major cause of cancer death among women worldwide. Understanding the mechanisms underlying breast cancer progression remains urgent for developing effective treatment strategies to eliminate breast cancer mortality. Our recent studies have demonstrated that Kr(&)#252;ppel-like transcriptional factor 8 (KLF8) plays a critical role for breast cancer progression. Other studies have shown that Epithelial stromal interaction 1 (EPSTI1), a recently identified stromal fibroblast-induced gene in non-invasive breast cancer cells and epidermal growth factor receptor (EGFR) are highly overexpressed in aggressively invasive breast carcinomas including triple negative breast cancers. In this thesis project, we demonstrate high co-overexpression of KLF8 with EPSTI1 as well as EGFR in invasive breast cancer cells and patient tumors. We also show that KLF8 upregulates the expression of EPSTI1 by directly binding and activating the EPSTI1 gene promoter, and KLF8 upregulates the expression of EGFR not only by directly activating the EGFR gene promoter but also by preventing EGFR translation from microRNA141-dependent inhibition. Genetic, signaling and animal cancer model analyses indicate that downstream of KLF8, EPSTI1 promotes the tumor invasion and metastasis by activating NF-?B through binding valosin containing protein (VCP) and subsequent degradation of I?B?, whereas EGFR promotes tumor growth and metastasis via activation of ERK. Taken together, these data identify EPSTI1 and EGFR as novel KLF8 targets in breast cancer and suggest that KLF8 may be targeted for new effective treatment of breast cancer.
Show less - Date Issued
- 2013
- Identifier
- CFE0005366, ucf:50474
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005366
- Title
- A novel link between Akt1 and Twist1 in ovarian tumor cell motility and invasiveness.
- Creator
-
Shah, Nirav, Altomare, Deborah, Zhao, Jihe, Khaled, Annette, University of Central Florida
- Abstract / Description
-
Ovarian cancer results in more deaths per year than any other cancer of the female reproductive system. The low survival rate is partly due to the lack of early detection and the susceptibility to relapse. The AKT serine threonine kinase plays a pivotal role in hallmark cellular processes for the progression of ovarian cancer, including tumor cell growth and migration. Therapeutic targeting of pan-AKT has been problematic, in part due to feedback mechanisms and crosstalk with other pathways....
Show moreOvarian cancer results in more deaths per year than any other cancer of the female reproductive system. The low survival rate is partly due to the lack of early detection and the susceptibility to relapse. The AKT serine threonine kinase plays a pivotal role in hallmark cellular processes for the progression of ovarian cancer, including tumor cell growth and migration. Therapeutic targeting of pan-AKT has been problematic, in part due to feedback mechanisms and crosstalk with other pathways. The hypothesis for this study is that AKT 1, -2 and -3 isoforms may have different roles and regulate cell processes in uniquely varied ways. A transgenic mouse model that expresses the SV40 T-antigen viral oncogene and is known to have dramatically increased susceptibility to ovarian cancer was utilized, and it had genetic inactivation of either AKT1 or AKT2 through targeted deletion of the individual genes because these isoforms have been implicated in this cancer. Primary ovarian tumor cell cultures were established and found to exhibit different morphology, proliferation and migration that may indicate a different role for the AKT1 and AKT2 isoforms in these contexts. Ovarian tumor cells with absence of AKT1 predominantly exhibited reduced cell migration when compared to cells with retention of AKT1 and absence of AKT2. Since AKT is known to be important for epithelial-mesenchymal transition (EMT), a process potentially associated with tumor cell metastasis, the expression of transcription factors implicated in EMT was assessed by real-time array analysis in ovarian tumor cells knocked-out for either AKT1 or AKT2. Twist1, one of the major players in EMT, was not detectable in the cells missing the AKT1 isoform. Results indicate an association of Twist1 with AKT1 in EMT and migration of ovarian tumors cells. This finding is significant because AKT2 has been implicated as the major player of cell migration in human breast cancer cells. Collectively, these findings support a tissue specific role of the AKT isoforms, and may provide insights regarding the most useful cell context in order to target components of the AKT signaling pathway indirectly affecting EMT in order to prevent tumor progression in patients with ovarian and perhaps other types of cancers.
Show less - Date Issued
- 2012
- Identifier
- CFE0004630, ucf:49916
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004630
- Title
- Characterization of Innate Immunity in the Female Reproductive Tract for the Prevention of HIV Acquisition.
- Creator
-
Eade, Colleen, Cole, Alexander, Jewett, Travis, Naser, Saleh, Khaled, Annette, University of Central Florida
- Abstract / Description
-
Human immunodeficiency virus (HIV) infects 30 million people worldwide. In sub-Saharan Africa, the region most affected by HIV, women comprise 60% of the infected population. Heterosexual transmission is a major mode of viral acquisition, mandating further research of the process and prevention of HIV acquisition via the female reproductive tract (FRT). The FRT is a dynamic environment, protected by host immune mechanisms and commensal microbes. The disruption of either of these elements can...
Show moreHuman immunodeficiency virus (HIV) infects 30 million people worldwide. In sub-Saharan Africa, the region most affected by HIV, women comprise 60% of the infected population. Heterosexual transmission is a major mode of viral acquisition, mandating further research of the process and prevention of HIV acquisition via the female reproductive tract (FRT). The FRT is a dynamic environment, protected by host immune mechanisms and commensal microbes. The disruption of either of these elements can increase susceptibility to HIV. Accordingly, one common risk factor for HIV acquisition is the microbial shift condition known as bacterial vaginosis (BV), which is characterized by the displacement of healthy lactobacilli by an overgrowth of pathogenic bacteria. As the bacteria responsible for BV pathogenicity and their interactions with host immunity are not understood, we sought to evaluate the effects of BV-associated bacteria on reproductive epithelia. Here we have characterized the interaction between BV-associated bacteria and the female reproductive tract by measuring cytokine and defensin induction in FRT epithelial cells following bacterial inoculation. Four BV-associated bacteria were evaluated alongside six lactobacilli for a comparative assessment. Our model showed good agreement with clinical BV trends; we observed a distinct cytokine and human ?-defensin-2 response to BV-associated bacteria, especially Atopobium vaginae, compared to most lactobacilli. One lactobacillus species, Lactobacillus vaginalis, induced an immune response similar to that elicited by BV-associated bacteria. These data provide an important prioritization of BV-associated bacteria and support further characterization of reproductive bacteria and their interactions with host epithelia. We next evaluated the effect of this interaction on HIV infection by investigating the soluble effectors secreted when FRT epithelial cells were cocultured with A. vaginae. We observed increased proviral activity mediated by secreted low molecular weight effectors, and determined that this activity was not likely mediated by cytokine responses. Instead, we identified a complex mixture containing several upregulated host proteins. Selected individual proteins from the mixture exhibited HIV-enhancing activity only when applied with the complex mixture of proviral factors, suggesting that HIV enhancement might be mediated by synergistic effects.In addition to characterizing the immune interactions that mediate the enhanced HIV acquisition associated with BV, we also evaluated the safety and efficacy of RC-101, a candidate vaginal microbicide being developed for the prevention of HIV transmission. RC-101 has been effective and well tolerated in preliminary cell culture and macaque models. However, the effect of RC-101 on primary vaginal tissues and resident vaginal microflora requires further evaluation. Here, we treated primary vaginal tissues and vaginal bacteria, both pathogenic and commensal, with RC-101 to investigate compatibility of this microbicide with FRT tissue and microflora. RC-101 was well tolerated by host tissues and commensal vaginal bacteria, while BV-associated bacteria were inhibited by RC-101. By establishing vaginal microflora, the specific antibacterial activity of RC-101 may provide a dual mechanism of HIV protection.
Show less - Date Issued
- 2013
- Identifier
- CFE0004677, ucf:49867
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004677
- Title
- Novel Cytokine Signaling and Molecular Therapeutic Strategy in Pancreatic Cancer.
- Creator
-
Gitto, Sarah, Altomare, Deborah, Khaled, Annette, Zhao, Jihe, Copik, Alicja, Masternak, Michal, University of Central Florida
- Abstract / Description
-
Pancreatic ductal adenocarcinoma (PDAC) is highly chemo-resistant and has a five year survival rate of (
Show morePancreatic ductal adenocarcinoma (PDAC) is highly chemo-resistant and has a five year survival rate of (<)8%. Risk factors of pancreatic cancer, such as chronic pancreatitis, help to elicit a pro-tumor immune response, and highly fibrotic environment that promotes tumorigenesis. To study how chronic pancreatitis promotes cancer initiation, traditional KRasG12D mice and double mutant Akt1Myr/KrasG12D mice were used to model microenvironment changes. Akt1Myr/KrasG12D mice were more susceptible to chronic tissue damage, accelerated tumor development and metastatic disease. These mice exhibited histological changes consistent with immune cell privilege, where M2 macrophages and non-cytotoxic eosinophils were co-localized with fibrotic regions. IL-5 expression was up regulated in pancreatic cells undergoing acinar to ductal metaplasia and then diminished in advanced lesions. Tumor cells treated with IL-5 exhibit increased migration and activation through STAT5 signaling. Collectively, the results suggest that eosinophils, which are responsive to IL-5, are key mediators in the pancreatic environment subjected to chronic inflammation and injury.Current therapeutics fall short in increasing patient survival. There remains an urgent need for innovative treatments and thus we tested difluoromethylornithine (DFMO) in combination with a novel polyamine transport inhibitor, Trimer44NMe, against Gemcitabine-resistant PDAC cells. Prior clinical failures when targeting polyamine biosynthesis with DFMO monotherapy may be due to tumor escape via an undefined polyamine transport system. In pancreatic tumor cells DFMO alone and with Trimer44NMe significantly reduced PDAC cell viability by inducing apoptosis or cell cycle arrest. In vivo orthotopic PDAC growth with DFMO treatment resulted in decreased c-Myc expression, a readout of polyamine pathway dysfunction. Moreover, dual inhibition significantly prolonged survival of tumor-bearing mice, and increased M1 macrophage infiltration and reduced FoxP3 expression. Collectively, these studies demonstrate that targeting polyamine pathways in PDAC is a promising immunomodulating therapy that increases survival.
Show less - Date Issued
- 2017
- Identifier
- CFE0007283, ucf:52168
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007283
- Title
- Chaperonin Containing TCP1 (CCT) as a Target for Cancer Therapy.
- Creator
-
Carr, Ana, Khaled, Annette, Altomare, Deborah, Tigno-Aranjuez, Justine, Fernandez-Valle, Cristina, University of Central Florida
- Abstract / Description
-
Treatments for aggressive cancers like triple negative breast cancer (TNBC) and small-cell lung cancer (SCLC) have not improved and remain associated with debilitating side effects. There is an unmet medical need for better, druggable targets and improved therapeutics. To this end, we investigated the role of Chaperonin-Containing TCP1 (CCT), an evolutionarily conserved protein-folding complex composed of eight subunits (CCT1-8), in oncogenesis. Our laboratory was the first to report that the...
Show moreTreatments for aggressive cancers like triple negative breast cancer (TNBC) and small-cell lung cancer (SCLC) have not improved and remain associated with debilitating side effects. There is an unmet medical need for better, druggable targets and improved therapeutics. To this end, we investigated the role of Chaperonin-Containing TCP1 (CCT), an evolutionarily conserved protein-folding complex composed of eight subunits (CCT1-8), in oncogenesis. Our laboratory was the first to report that the CCT2 subunit is highly expressed in breast cancer and could be therapeutically targeted. To determine whether CCT is a marker of disease progression in other cancers, we analyzed CCT2 gene expression in liver, prostate and lung cancer, using publicly available genetic databases, and confirmed findings by assessing CCT2 and client proteins, like STAT3, in tumor tissues by immunohistochemistry. We found that CCT2 was high in all cancers, especially SCLC, and correlated with decreased patient survival. We tested CT20p, the peptide therapeutic developed by our laboratory to inhibit CCT, on SCLC and primary lung cells, finding that CT20p was only cytotoxic to SCLC cells. Since SCLC currently lacks targeted therapeutics, our work yielded a new targeted agent that could improve lung cancer mortality. To establish a mechanism of action for CT20p, we partially knocked out CCT2 in TNBC cells, which decreased tumorigenicity in mice and reduced levels of essential proteins like STAT3. To confirm, we overexpressed CCT2 in non-tumorigenic cells and conferred tumor-like characteristics such as increased migration and elevated STAT3. These studies positioned us to develop and validate a strategy for discovery of new small molecule inhibitors of CCT. We thus advanced the field of cancer research by demonstrating that CCT could have diagnostic potential for cancers, such as SCLC and TNBC, that are a significant cause of human death and showed that targeting CCT is a promising therapeutic approach.
Show less - Date Issued
- 2017
- Identifier
- CFE0007280, ucf:52191
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007280
- Title
- Manipulation of host signal transduction pathways and cytoskeleton functions by invasive bacterium Listeria monocytogenes and Chlamydia trachomatis.
- Creator
-
Jiwani, Shahanawaz, Jewett, Travis, Zervos, Antonis, Khaled, Annette, Teter, Kenneth, University of Central Florida
- Abstract / Description
-
Infectious disease remains one of the leading causes of morbidity and mortality worldwide. Many bacteria that cause disease have the capacity to enter into eukaryotic cells such as epithelial cells and tissue macrophages. Gaining access into the intracellular environment is one of the most critical steps in their survival and/or in pathogenesis. The entry mechanisms employed by these organisms vary considerably, but most mechanisms involve sabotaging and manipulating host cell functions....
Show moreInfectious disease remains one of the leading causes of morbidity and mortality worldwide. Many bacteria that cause disease have the capacity to enter into eukaryotic cells such as epithelial cells and tissue macrophages. Gaining access into the intracellular environment is one of the most critical steps in their survival and/or in pathogenesis. The entry mechanisms employed by these organisms vary considerably, but most mechanisms involve sabotaging and manipulating host cell functions. Invasion of epithelial cells involves triggering host signal transduction mechanisms to induce cytoskeleton rearrangement, thereby facilitating bacterial uptake. My work focuses on understanding the molecular mechanisms employed by bacterial pathogen Listeria monocytogenes and Chlamydia trachomatis to gain access into the host cells in order to cause the disease.In first part of my thesis I investigated the mechanism of Listeria monocytogenes entry. Listeria, a facultative intracellular organism, is responsible for causing meningitis, septicemia, gastroenteritis and abortions. Critical for Listeria virulence is its ability to get internalized, replicates and spread into adjacent host cells. One of the pathways of Listeria internalization into mammalian cells is promoted by binding of its surface protein Internalin B (InlB) to host receptor MET. Studies done in the past demonstrated a critical role of host type IA Phosphoinositide (PI) 3-kinase in controlling cytoskeleton rearrangement and entry of Listeria downstream of MET. An important unresolved question was how activation of PI3K results in cytoskeleton rearrangements that promote Listeria entry. In this work, we identified 9 host signaling molecules, that includes Rab 5c, SWAP 70, GIT1, PDK1, mTor, ARAP2, ARNO, DAPP1 (&) PKC-?, acting downstream of type IA Phosphoinositide (PI) 3-kinase to regulate changes in host cytoskeleton to cause Listeria entry.Second part of my thesis involved studying the functions of chlamydial effector protein Tarp in its invasion. Infection caused by Chlamydia Trachomatis is the most common sexually transmitted disease resulting in uro-genital diseases, LGV, ectopic pregnancy and infertility. It is also responsible for causing trachoma, the leading cause of preventable blindness in third world countries. Being an obligate intracellular pathogen, gaining access into intracellular environment is the most critical step in lifecycle and pathogenesis of Chlamydia. Previous studies demonstrate the role of both chlamydial and host actin nucleators, Tarp and Arp2/3 complex respectively, in mediating Chlamydial entry into non-phagocytic cells. But the molecular details of these processes were not well understood. In this study, we demonstrate novel function of Tarp protein to form actin bundles by its ability to bind filamentous actin through newly identified FAB domains. And we also provide bio-chemical evidence that Tarp and Arp2/3 complex works in conjunction to cause changes in host cytoskeleton that effectively culminate into bacterial uptake by host cells.Overall, this research was a significant step in enhancing our understanding, at a molecular level, to pathogenesis of infections caused by Listeria monocytogenes and Chlamydia trachomatis.
Show less - Date Issued
- 2012
- Identifier
- CFE0004555, ucf:49225
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004555
- Title
- The Effects of Presentation Mode and Pace on Learning Immunology with Computer Simulation: A Cognitive Evaluation of a Multimedia Learning Resource.
- Creator
-
Bradley-Radakovich, Kristy, Kincaid, John, Khaled, Annette, McDaniel, Rudy, Greenwood-Ericksen, Adams, University of Central Florida
- Abstract / Description
-
Multimedia learning tools have the potential to benefit instructors and learners as supplemental learning materials. However, when such tools are designed inappropriately, this can increase cognitive taxation and impede learning, rendering the tools ineffective. Guided by the theoretical underpinnings provided by cognitive load theory and the cognitive theory of multimedia learning, this study sought to empirically evaluate the effectiveness of a multimedia simulation tool aimed at teaching...
Show moreMultimedia learning tools have the potential to benefit instructors and learners as supplemental learning materials. However, when such tools are designed inappropriately, this can increase cognitive taxation and impede learning, rendering the tools ineffective. Guided by the theoretical underpinnings provided by cognitive load theory and the cognitive theory of multimedia learning, this study sought to empirically evaluate the effectiveness of a multimedia simulation tool aimed at teaching immunology to novices in an instructional setting. The instructional mode and pace of the tool were manipulated, the three levels of each variable yielding nine experimental groups. The effects of mode and pace on workload and learning scores were observed. The results of this study did not support the theory-driven hypotheses. No significant learning gains were found between the configuration groups, however overall significant learning gains were subsequently found when disregarding mode and pace configuration. Pace was found to influence workload such that fast pace presentations significantly increased workload ratings and a significant interaction of mode and pace was found for workload ratings. The findings suggest that the learning material was too high in intrinsic load and the working memory of the learners too highly taxed for the benefits of applying the design principles to be observed. Results also illustrate a potential exception to the conditions of the design principles when complex terminology is to be presented. Workload findings interpreted in the context of stress adaptation potentially indicate points at which learners at maximum capacity begin to exhibit performance decrements.
Show less - Date Issued
- 2011
- Identifier
- CFE0004090, ucf:49150
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004090
- Title
- Delineating key genetic components on linear plasmid 36 that contribute to its essential role in Borrelia burgdorferi mammalian infectivity.
- Creator
-
Choudhury, Tisha, Jewett, Mollie, Khaled, Annette, Self, William, Cole, Alexander, University of Central Florida
- Abstract / Description
-
The spirochete Borrelia burgdorferi is the etiologic agent of Lyme disease. This pathogen has a complex enzootic life cycle that involves passage between the tick vector (Ixodes scapularis) and various vertebrate hosts with humans being inadvertent hosts. There is a pressing need to study the genetic aspects of the B. burgdorferi infectious cycle and particularly spirochete genes involved in mammalian infectivity so as to develop novel therapeutic and diagnostic strategies to combat Lyme...
Show moreThe spirochete Borrelia burgdorferi is the etiologic agent of Lyme disease. This pathogen has a complex enzootic life cycle that involves passage between the tick vector (Ixodes scapularis) and various vertebrate hosts with humans being inadvertent hosts. There is a pressing need to study the genetic aspects of the B. burgdorferi infectious cycle and particularly spirochete genes involved in mammalian infectivity so as to develop novel therapeutic and diagnostic strategies to combat Lyme disease. The B. burgdorferi genome is fragmented and comprised of a single 900 kb linear chromosome and multiple linear and circular plasmids. It has been observed that plasmids are lost during serial passage and manipulation in vitro and the loss of some of the plasmids has been shown to be related to the loss of infectivity and persistence in the host. One such plasmid is linear plasmid 36 (lp36). lp36 is approximately 36kb in size and carries 56 putative open reading frames a majority of which have no predicted function. B. burgdorferi lacking lp36 show no deficiency in survival in ticks; however, these mutant spirochetes are highly attenuated for mammalian infectivity. The genetic components of this plasmid that contribute to its function in mammalian infectivity have yet to be clearly defined. Using an in vivo expression technology (IVET) based genetic screen the lp36-encoded gene bbk46 was identified as a candidate B. burgdorferi gene that is expressed during mammalian infection. Herein we present evidence that bbk46 is required for B. burgdorferi persistent infection of immunocompetent mice. Our data support a molecular model of immune evasion by which bbk46 functions as an RNA to regulate expression of the antigenic variation protein VlsE. These data represent the first demonstration of a regulatory mechanism critical for controlling vlsE gene expression. Moreover these findings further define the critical role of linear plasmid 36 in Borrelia burgdorferi pathogenesis.
Show less - Date Issued
- 2013
- Identifier
- CFE0004982, ucf:49566
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004982
- Title
- Folate conjugated hyperbranched polyester nanoparticles for prostate tumor-targeted delivery of a cytotoxic peptide via prostate specific membrane antigen.
- Creator
-
Flores-Fernandez, Orielyz, Perez Figueroa, J. Manuel, Campiglia, Andres, Yestrebsky, Cherie, Harper, James, Khaled, Annette, University of Central Florida
- Abstract / Description
-
Prostate Cancer is the second most deadly cancer in men, after lung cancer. The need for new and effective therapeutics that can constrain prostate cancer progression are challenged by the lack of suitable delivery strategies that target prostate cancer tissue. To study CT20p as potential chemotherapeutic agent in the treatment of prostate cancer we proposed the use of targetable hyperbranched polyester (HBPE) based nanoparticles as delivery system. Folic acid was conjugated to the...
Show moreProstate Cancer is the second most deadly cancer in men, after lung cancer. The need for new and effective therapeutics that can constrain prostate cancer progression are challenged by the lack of suitable delivery strategies that target prostate cancer tissue. To study CT20p as potential chemotherapeutic agent in the treatment of prostate cancer we proposed the use of targetable hyperbranched polyester (HBPE) based nanoparticles as delivery system. Folic acid was conjugated to the nanocarrier to improve the selectivity of the nanoparticle towards specific cell surface targets in prostate cancer cell lines. Specifically we evaluated LNCaP that up-regulated the PSMA receptor. The synthesis of folate conjugated hyperbranched polyester nanoparticles was accomplished using an aliphatic and biodegradable hyperbranched polyester (HBPE). HBPE was prepared from commercially available diethyl malonate and 4-bromobutyl acetate. Our AB2 type monomer displays a three-bond connectivity that grows three-dimensionally under specific polymerization conditions. The product, HBPE, is a polymer with globular configuration that contains surface carboxylic acid groups and holds hydrophobic cavities. Carboxylated HBPE nanoparticles were synthesized via solvent diffusion method. A variety of hydrophobic cargos including: dyes (DiR and DiI) and the cytotoxic peptide CT20p were successfully encapsulated. DLS along with STEM imaging reveal nanoparticle preparations with ~100 nm size. Using water-soluble carbodiimide chemistry, surface modifications were accomplished. Available carboxylic acid groups were conjugated to aminated folic acid to yield folate functionalized nanoparticles.We explore the targeting capability of the Folate-HBPE nanoparticles and demonstrated that the cell internalization of Folate-HBPE into prostate cancer cell lines (LNCaP and PSMA (+) PC-3) was attained via a PSMA-mediated targeting mechanism. Furthermore, when CT20p was delivered to PSMA expressing PCa cells, detachment and death was observed; together with a reduction in the levels of ?1 integrin (CD29) expression, an integrin implicate in cell communication and cell adhesion. CT20p inhibits cell proliferation within 24 h and produce significant cell death after 48 h post treatment. The IC50 of CT20p was calculated at ~7 nM. Additionally, we investigated the capability of Folate-HBPE(CT20p) to perform as a therapeutic agent, in an in vivo setup, using a murine prostate tumor model. The Folate-PEG-HBPE NPs protected CT20p while in circulation and allowed effective uptake by PSMA-mediated targeting. Treatment with Folate-HBPE(CT20p) display localize tumor targeting and significant tumor growth inhibition in PSMA(+) PCa cell lines within days. Together these results suggest the potential of Folate-HBPE(CT20p) nanoparticles in the treatment of prostate cancer.
Show less - Date Issued
- 2015
- Identifier
- CFE0006216, ucf:51112
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006216
- Title
- Proteomic Analysis Delineates the Signaling Networks of Plasmodium falciparum.
- Creator
-
Pease, Brittany, Chakrabarti, Debopam, Khaled, Annette, Jewett, Mollie, Chakrabarti, Ratna, Cole, Alexander, University of Central Florida
- Abstract / Description
-
Malaria is a life-threatening disease caused by Plasmodium parasites that are spread through the bites of infected mosquito vectors. It is a worldwide pandemic that threatens 3.4 billion people annually. Currently, there are only a few validated Plasmodium drug targets, while drug resistance continues to rise. This marks the urgency for the development of novel parasite-specific therapeutics. Plasmodium falciparum diverges from the paradigm of the eukaryotic cell cycle by undergoing multiple...
Show moreMalaria is a life-threatening disease caused by Plasmodium parasites that are spread through the bites of infected mosquito vectors. It is a worldwide pandemic that threatens 3.4 billion people annually. Currently, there are only a few validated Plasmodium drug targets, while drug resistance continues to rise. This marks the urgency for the development of novel parasite-specific therapeutics. Plasmodium falciparum diverges from the paradigm of the eukaryotic cell cycle by undergoing multiple rounds of DNA replication and nuclear division without cytokinesis. A better understanding of the molecular switches that coordinate the progression of the parasite through the intraerythrocytic developmental stages will be of fundamental importance for the design of rational intervention strategies. To achieve this goal, we performed an isobaric tag-based approach for a system-wide quantitative analysis of protein expression and site-specific phosphorylation events of the Plasmodium asexual developmental cycle in the red blood cells. This study identified 2,767 proteins, 1,337 phosphoproteins, and 6,293 phosphorylation sites. Approximately 34% of identified proteins and 75% of phosphorylation sites exhibit changes in abundance as the intraerythrocytic cycle progresses. Because the links between Plasmodium protein kinases as key cell cycle regulators to cellular events are largely unknown, it is of importance to define their cognate physiological substrates. To test the hypothesis that genetic screening would be a useful approach for discovery of candidate substrates of a protein kinase, we used the orphan kinase PfPK7 as a model. Our comparison of the phosphoproteome profiles between the wild-type 3D7 and PfPK7- parasites identified 146 proteins with 239 phosphorylation sites exhibiting decreased phosphorylation in the absence of PfPK7 at the developmental stages where nuclear division and merozoite formation occur. Further analysis of the decreased phosphorylated events revealed three motifs that are enriched among phosphorylated sites in proteins that are down regulated. In vitro kinase assays were done to validate the potential substrates of PfPK7 and to elucidate the signaling events that are regulated by PfPK7. In parallel to our experimental analysis, we used a computational approach for substrate prediction from our phosphoproteome dataset. This analysis identified 43 distinct phosphorylation motifs and a range of proline-directed potential MAPK/CDK substrates. To identify substrates/ interactors of Plasmodium CDK-like kinases, we also used HA-tagged CDK-like kinases, PfPK6 and Pfmrk lines. Co-immunoprecipitation of the HA-tagged PfPK6 and Pfmrk baits, followed by mass spectrometric analyses, identified the components of the protein interaction complexes of these kinases. Our analyses of HA-PfPK6 and HA-Pfmrk immunoprecipitates identified 15 and 21 proteins in the interaction complex, respectively. The ability of recombinant PfPK6 and Pfmrk to interact and/or utilize any of the proteins identified in the interaction complex as substrates was verified through in vitro kinase assays and pull-down analysis. This study is the most comprehensive definition of the constitutive and regulated expression of the Plasmodium proteome during the intraerythrocytic developmental cycle, and offered an insight into the dynamics of phosphorylation during the asexual cycle progression [1]. In summary, this study has 1) defined the constitutive and regulated expression of the Plasmodium proteome during its asexual life cycle, 2) demonstrated that fluctuation and reversible phosphorylation is important for the regulation of P. falciparum's unique cell cycle, 3) provided the foundation for quantitative phosphoproteomic analysis of kinase negative mutants to understand their function, 4) provided a major step towards defining kinase-substrate pairs operative within parasite's signaling networks, and 5) generated a preliminary interactome for PfPK6.
Show less - Date Issued
- 2015
- Identifier
- CFE0005863, ucf:50898
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005863
- Title
- Targeted Therapy Development for Neurofibromatosis Type 2.
- Creator
-
Fuse, Marisa, Fernandez-Valle, Cristina, Lambert, Stephen, Altomare, Deborah, Khaled, Annette, University of Central Florida
- Abstract / Description
-
Neurofibromatosis type 2 (NF2) is a debilitating disease characterized by the formation of bilateral vestibular schwannomas, which compress the vestibulocochlear nerve and cause deafness. Additional peripheral schwannomas, meningiomas and ependymomas may also form. NF2 is caused by mutations in the NF2 gene, resulting in the loss of function of the merlin tumor suppressor. Merlin functions in multiple signaling pathways and its absence in Schwann cells yields increased cell survival and...
Show moreNeurofibromatosis type 2 (NF2) is a debilitating disease characterized by the formation of bilateral vestibular schwannomas, which compress the vestibulocochlear nerve and cause deafness. Additional peripheral schwannomas, meningiomas and ependymomas may also form. NF2 is caused by mutations in the NF2 gene, resulting in the loss of function of the merlin tumor suppressor. Merlin functions in multiple signaling pathways and its absence in Schwann cells yields increased cell survival and proliferation, thereby causing schwannoma formation. First line treatment for NF2 is watchful waiting and surgical removal of tumors, potentially resulting in facial paralysis and deafness. To date, there are no pharmacological options for patients with NF2. Since the first clinical trials were completed in 2012, only 5 drugs have been investigated in NF2 patients. Few drugs have elicited a measurable radiographic tumor response and most only result in temporary hearing improvement in a small subset of patients. Development of novel therapeutic compounds is a slow, expensive process. However, re-purposing FDA-approved drugs for NF2 accelerates the transfer of efficacious drugs to the clinic. This dissertation used a systematic approach to identify drugs capable of reducing NF2-associated schwannoma growth. An initial screen revealed drugs that reduced viability of mouse and human merlin-deficient Schwann cells. Efficacious drugs were then advanced to an allograft mouse model of NF2 to identify those that reduced tumor growth in vivo. Drug efficacy was also examined in human primary schwannoma cells. We showed that Src, c-MET and MEK inhibitors reduced viability of merlin-deficient Schwann cells both in vitro and in vivo. We also identified a combination treatment of Src and c-MET inhibitors that induced apoptosis, suggesting the potential for preventing tumor recurrence after completion of drug treatment. The work presented here provides valuable pre-clinical evidence for the advancement of several approved drugs to clinical trials for NF2-associated schwannomas.
Show less - Date Issued
- 2017
- Identifier
- CFE0006877, ucf:51707
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006877
- Title
- A major double strand repair pathway and cancer-associated circulating proteins are effecters of epigenetic revision.
- Creator
-
Allen, Brittany, Masternak, Michal, Khaled, Annette, Zhao, Jihe, Muller, Mark, Siddiqi, Shadab, University of Central Florida
- Abstract / Description
-
DNA methylation is a vital epigenetic process that acts as a major control mechanism for gene expression. In addition to its essential role in many normal cellular processes, it is also implicated in a wide variety of disease states and processes including cancer. Along with genetic mutations, aberrant DNA methylation patterns, specifically the inappropriate DNA methylation or demethylation of CpG residues, may activate oncogenes or suppress tumor suppressor genes, respectively. These changes...
Show moreDNA methylation is a vital epigenetic process that acts as a major control mechanism for gene expression. In addition to its essential role in many normal cellular processes, it is also implicated in a wide variety of disease states and processes including cancer. Along with genetic mutations, aberrant DNA methylation patterns, specifically the inappropriate DNA methylation or demethylation of CpG residues, may activate oncogenes or suppress tumor suppressor genes, respectively. These changes can generate or facilitate the progression of tumorigenesis and tend to accumulate throughout the development of cancer. Although they play such a major role in cancer and in other diseases, it remains unclear what causes these epigenetic revisions to occur. This dissertation will focus on uncovering mechanisms that are sources of epigenetic revision, specifically as they relate to cancer. Due to rapid cell division and increased DNA damage, cells are increasingly dependent on DNA repair as they continue on a path of tumorigenic progression. We hypothesize that DNA repair, specifically the repair of DNA double strand breaks (DSB) by Non-Homologous End Joining (NHEJ) may play a role in inappropriate epigenetic revision. Using a GFP reporter system inserted into the genome of HeLa cells, we are able to induce targeted DNA damage that enables the cells, after successfully undergoing NHEJ repair, to express WT GFP. These GFP+ cells were segregated into two expression classes, one with robust expression (Bright) and the other with reduced expression (Dim). Using a DNA hypomethylating drug (AzadC) we were able to demonstrate that the different GFP expression levels was due to differential methylation statuses of CpGs in regions on either side of the break site. Deep sequencing analysis of this area in sorted Bright and Dim populations revealed a collection of different epi-alleles that display patterns of DNA methylation following repair by NHEJ. These patterns differ between Bright and Dim cells which are hypo- and hypermethylated, respectively, and between the post-repair populations and the original, uncut cells. These data suggest that NHEJ repair facilitates a rewrite of the methylation landscape in repaired genes, elucidating one potential source for the altered methylation patterns seen in cancer cells.The Dim cells generated during this study are known to have a hypermethylated GFP gene that is correlated with reduced expression, allowing it to be used as a screening tool for hypomethylating agents. We used this tool to screen the blood serum of patients with head and neck squamous cell carcinoma (HNSCC). We found that the serum from HNSCC patients, but not from healthy individuals, contains some factor that causes hypomethylation in exposed cells. Further, we were able to identify this factor as a protein capable of effecting changes in DNA methylation, gene expression, and miRNA levels in the treated Dim cells. The novel concept presented in this study has immense implications on the study of cancer progression as it evidences circulating proteins, presumably released by cancer cells, which are able to effect gene expression in cells that are distal to the location of the cancer. Further, the fact that these proteins are in circulation makes them a potential target for use in diagnostics. Changes in DNA methylation play a major role in the development of cancer and understanding the mechanisms by which this occurs could provide new therapeutic targets for preventing this process from contributing to tumorigenesis. This dissertation presents potential sources of epigenetic revision in cancer and thus provides answers to a major question that has yet to be answered in the area of cancer research.
Show less - Date Issued
- 2017
- Identifier
- CFE0006555, ucf:51333
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006555
- Title
- Target validation for Neurofibromatosis Type 2 therapeutics.
- Creator
-
Petrilli Guinart, Alejandra, Fernandez-Valle, Cristina, Altomare, Deborah, Khaled, Annette, Lambert, Stephen, University of Central Florida
- Abstract / Description
-
Neurofibromatosis type 2 (NF2) is a benign tumor disease of the nervous system. Development of bilateral vestibular schwannomas is characteristic of NF2; however patients frequently present schwannomas on other nerves, as well as meningiomas and ependymomas. Currently, there are no drug therapies for NF2. There is an urgent need for development of NF2 therapeutics and this dissertation presents two independent potential therapeutic targets.The disease is caused by mutations in the NF2 gene...
Show moreNeurofibromatosis type 2 (NF2) is a benign tumor disease of the nervous system. Development of bilateral vestibular schwannomas is characteristic of NF2; however patients frequently present schwannomas on other nerves, as well as meningiomas and ependymomas. Currently, there are no drug therapies for NF2. There is an urgent need for development of NF2 therapeutics and this dissertation presents two independent potential therapeutic targets.The disease is caused by mutations in the NF2 gene that encodes a tumor suppressor called merlin. Loss of merlin function is associated with increased activity of Rac and p21-activated kinases (PAK) and deregulation of cytoskeletal organization. LIM domain kinases (LIMK1 and 2) are substrates for Cdc42/Rac-PAK, and modulate actin dynamics by phosphorylating cofilin, an actin severing and depolymerizing agent. LIMKs also translocate into the nucleus and regulate cell cycle progression. Here we report that mouse Schwann cells (MSCs) in which merlin function is lost as a result of Nf2 exon2 deletion (Nf2 delta Ex2) exhibited increased levels of LIMK1, LIMK2, and active phospho-Thr508/505-LIMK1/2, as well as phospho-Ser3-cofilin, compared to wild-type normal MSCs. Similarly, levels of LIMK1 and 2 total protein and active phosphorylated forms were elevated in human vestibular schwannomas compared to normal human Schwann cells (SCs). Reintroduction of wild-type NF2 into Nf2?delta Ex2 MSC reduced LIMK1 and LIMK2 levels. Pharmacological inhibition of LIMK with BMS-5, decreased the viability of Nf2?delta Ex2 MSCs in a dose-dependent manner, but did not affect viability of control MSCs. Similarly, LIMK knockdown decreased viability of Nf2?delta Ex2 MSCs. The decreased viability of Nf2?delta Ex2 MSCs was due to inhibition of cell cycle progression as evidenced by accumulation of cells in G2/M phase. Inhibition of LIMKs arrest cells in early mitosis by decreasing Aurora A activation and cofilin phosphorylation.To increase the search for NF2 therapeutics, we applied an alternative approach to drug discovery with an unbiased pilot high-throughput screen of the Library of Pharmacologically Active Compounds. We assayed for compounds capable of reducing viability of Nf2?delta Ex2 MSC as a cellular model for human NF2 schwannomas. AGK2, a SIRT2 (sirtuin 2) inhibitor, was identified as a candidate compound. SIRT2, a mammalian sirtuin, is a NAD+-dependent protein deacetylase. We show that Nf2?delta Ex2 MSC have higher expression levels of SIRT2 and lower levels of overall lysine acetylation than wild-type control MSC. Pharmacological inhibition of SIRT2 decreases Nf2?delta Ex2 MSC viability in a dose dependent manner without substantially reducing wild-type MSC viability. Inhibition of SIRT2 activity in Nf2?delta Ex2 MSC causes cell death accompanied by release of the necrotic markers lactate dehydrogenase and high mobility group box 1 protein into the medium in the absence of significant apoptosis, autophagy, or cell cycle arrest.Overall this work uncovered two novel potential therapeutic targets, LIMK and SIRT2 for NF2 and tumors associated with merlin deficiency.
Show less - Date Issued
- 2013
- Identifier
- CFE0005398, ucf:50453
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005398
- Title
- Amyotrophic Lateral Sclerosis: mechanism behind mutant SOD toxicity and improving current therapeutic strategies.
- Creator
-
Dennys, Cassandra, Estevez, Alvaro, Kim, Yoon-Seong, Fernandez-Valle, Cristina, Khaled, Annette, University of Central Florida
- Abstract / Description
-
Amyotrophic Lateral Sclerosis (ALS) is an always lethal motor neuron disease with unknown pathogenesis. Inhibitors of the molecular chaperone heat shock protein 90 (Hsp90) have limited neuroprotection in some models of motor neuron degeneration. However the direct effect of Hsp90 inhibition on motor neurons is unknown. Here we show that Hsp90 inhibition induced motor neuron death through activation of the P2X7 receptor. Motor neuron death required phosphatase and tensein homolog (PTEN)...
Show moreAmyotrophic Lateral Sclerosis (ALS) is an always lethal motor neuron disease with unknown pathogenesis. Inhibitors of the molecular chaperone heat shock protein 90 (Hsp90) have limited neuroprotection in some models of motor neuron degeneration. However the direct effect of Hsp90 inhibition on motor neurons is unknown. Here we show that Hsp90 inhibition induced motor neuron death through activation of the P2X7 receptor. Motor neuron death required phosphatase and tensein homolog (PTEN)-mediated inhibition of the PI3K/AKT pathway leading to Fas receptor activation and caspase dependent death. The relevance of Hsp90 for motor neuron survival was investigated in mutant Cu/Zn superoxide dismutase (SOD) transgenic animal models for ALS. Nitrated Hsp90, a posttranslational modification known to induce cell death (Franco, Ye et al. 2013), was present in motor neurons after intracellular release of zinc deficient (Zn, D83S) and the SOD in which copper binding site was genetically ablated (Q) but not after copper deficient (Cu) wild type SOD. Zn deficient and Q mutant SOD induced motor neuron death in a peroxynitrite mediated and copper dependent mechanism. Nitrated Hsp90 was not detected in the spinal cord of transgenic animals for ALS-mutant SOD animal models until disease onset. Increased nitrated Hsp90 concentrations correlated with disease progression. Addition of Zn or Q SOD to nontransgenic brain homogenate treated with peroxynitrite led to an increase level of nitrotyrosine in comparison to wild type controls. However, in the same samples there was a 2 to 10 time increase in Hsp90 nitration as compared to nitrotyrosine. The selective increase is likely due to the binding of Hsp90 to Zn deficient and Q SOD as oppose to wild type SOD. These results suggest that Hsp90 nitration facilitated by mutant SOD may cause motor neuron degeneration in ALS. Targeted inhibition of nitrated Hsp90 may be a novel therapeutic approach for ALS. An alternative therapeutic strategy is to target the production of survival factors by glial cells. Riluzole is the only FDA approved drug for the treatment of ALS and it shows a small but significant increase in patient lifespan. Our results show that acute riluzole treatment stimulated trophic factor production by astrocytes and Schwann cells. However long-term exposure reversed and even inhibited the production of trophic factors, an observation that may explain the modest increase in patient survival in clinical trials. Discontinuous riluzole treatment can maintain elevated trophic factor levels and prevent trophic factor reduction in spinal cords of nontransgenic animals. These results suggest that discontinuous riluzole administration may improve ALS patient survival. In summary, we demonstrated that Hsp90 has an essential function in the regulation of motor neuron survival. We have also shown that Hsp90 was nitrated in the presence of mutant SOD and was present during symptom onset and increases as disease progresses, which may explain the toxic gain of function of mutant SOD. Finally we demonstrate a biphasic effect of riluzole on trophic factor production and propose changes in administration to improve effects in ALS patients.
Show less - Date Issued
- 2015
- Identifier
- CFE0005785, ucf:50069
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005785
- Title
- Preparation, Characterization, and Delivery of Antibodies Binding to a Model Oncogenic RNA, Human Initiator tRNA.
- Creator
-
Archer, Jennifer, Santra, Swadeshmukul, Ye, Jingdong, Ye, Jingdong, Self, William, Khaled, Annette, University of Central Florida
- Abstract / Description
-
Non-coding RNAs (ncRNAs) account for a higher percent of the genome than coding mRNAs, and are implicated in human disease such as cancer, neurological, cardiac and many others. While the majority of ncRNAs involved in disease were originally attributed to a class of RNAs called micro RNAs (miRNAs) with a small size of only about 19 -24 base pairs, emerging research has now demonstrated a class of long non-coding RNAs (lncRNAs) that have a size of over 200 base pairs to be responsible for...
Show moreNon-coding RNAs (ncRNAs) account for a higher percent of the genome than coding mRNAs, and are implicated in human disease such as cancer, neurological, cardiac and many others. While the majority of ncRNAs involved in disease were originally attributed to a class of RNAs called micro RNAs (miRNAs) with a small size of only about 19 -24 base pairs, emerging research has now demonstrated a class of long non-coding RNAs (lncRNAs) that have a size of over 200 base pairs to be responsible for gene regulation and other functional roles and have also found to contribute to pathogenesis in humans. The increased size and structural complexity require novel tools to study their interactions beyond RNA interference. Synthetic antibodies are classic tools and therapeutics utilized to study and treat proteins involved in human disease. Likewise we hypothesize that structured RNAs can also take advantage of synthetic antibodies to probe their functions and be utilized as therapeutics.Currently, antibodies have been raised against microbial riboswitches and other structured RNAs of single-celled organisms, and only one human structured RNA to the best of our knowledge. However, no one has yet to create a synthetic antibody capable of behaving as a therapeutic against a structured RNA. We therefore sought to raise an antibody Fab against a structured RNA, human initiator tRNA, a model oncogenic non-coding RNA and demonstrate its efficacy in vitro. We then characterized the antibody and explored delivery options in cancer cells including the use of nanoparticle delivery systems. With the emerging transcriptome revealing new ncRNAs implicated in human disease, our research has begun to address a new therapeutic strategy, laying down the foundation for the future of structured RNA-targeted therapies.
Show less - Date Issued
- 2014
- Identifier
- CFE0005756, ucf:50072
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005756
- Title
- Novel Immunogens of Cellular Immunity Revealed using in vitro Human Cell-Based Approach.
- Creator
-
Schanen, Brian, Self, William, Warren, William, Khaled, Annette, Seal, Sudipta, Zervos, Antonis, University of Central Florida
- Abstract / Description
-
Nanotechnology has undergone rapid expansion largely as a result of its enormous potential for applications as biomaterials, drug delivery vehicles, cancer therapeutics, and immunopotentiators. Despite this wave of interest and broad appeal for nanoparticles, evidence of their effect to the human immune system remains scarce. Concerns rise as studies on nanoparticle toxicology continue to emerge indicating that nanomaterials can be acutely toxic and can have long term inflammatory effects as...
Show moreNanotechnology has undergone rapid expansion largely as a result of its enormous potential for applications as biomaterials, drug delivery vehicles, cancer therapeutics, and immunopotentiators. Despite this wave of interest and broad appeal for nanoparticles, evidence of their effect to the human immune system remains scarce. Concerns rise as studies on nanoparticle toxicology continue to emerge indicating that nanomaterials can be acutely toxic and can have long term inflammatory effects as seen in animal models. Based on these findings and the rise in the development of nanoparticle technologies targeting in vivo applications, the urgency to characterize nanomaterial immunogenicity is paramount.Nanoparticles harbor great potential because they possess unique physicochemical properties compared to their larger counter parts as a result of quantum-size effects and their inherent large surface area to volume ratio. These physicochemical properties govern how a nanoparticle will behave in its environment. However, researchers have only just begun to catalogue the biological effect these properties illicit. We took it upon ourselves to investigate nanoparticle size-induced effects using TiO2, one of the most widely manufactured nanoparticles, as a model. We studied these effects in dendritic cells across a human donor pool. We examined dendritic cells because they have an inimitable functional role bridging the innate and adaptive arms of immunity. From this work we found that TiO2 nanoparticles can activate human dendritic cells to become pro-inflammatory in a size-dependent manner as compared to its micron-sized counterpart, revealing novel immune cell recognition and activation by a crystalline nanomaterial.Having identified nanomaterial size as a contributing feature of nanoparticle induced immunopotentiation, we became interested if additional physicochemical properties such as surface reactivity or catalytic behavior could also be immunostimulatory. Moreover, because we witnessed a stimulatory effect to dendritic cells following nanoparticle treatment, we were curious how these nanoparticle-touched dendritic cells would impact adaptive immunity. Since TiO2 acts as an oxidant we chose an antioxidant nanoparticle, CeO2, as a counterpart to explore how divergent nanoparticle surface reactivity impacts innate and adaptive immunity. We focused on the effect these nanoparticles had on human dendritic cells and TH cells as a strategy towards defining their impact to cellular immunity. Combined, we report that TiO2 nanoparticles potentiate DC maturation inducing the secretion of IL-12p70 and IL-1?, while treatment with CeO2 nanoparticles induced IL-10, a hallmark of suppression. When delivered to T cells alone TiO2 nanoparticles induced stronger proliferation in comparison to CeO2 which stimulated TReg differentiation. When co-cultured in allogeneic T cell assays, the materials directed alternate TH polarization whereby TiO2 drives largely a TH1 dominate response, whereas CeO2 was largely TH2 bias. Combined, we report a novel immunomodulatory capacity of nanomaterials with catalytic activity. While unintentional exposure to these nanomaterials could pose a serious health risk, development and targeted use of such immunomodulatory nanoparticles could provide researchers with new tools for novel adjuvant strategies or therapeutics.
Show less - Date Issued
- 2012
- Identifier
- CFE0004629, ucf:49927
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004629