Cell Biology Commons^™

Immune Recognition Of Self Nucleic Acids Driven By Endogenous Antimicrobial Peptides: Role In Autoimmunity, Dipyaman Ganguly

Dissertations and Theses (Open Access)

Innate immune recognition of extracellular host-derived self-DNA and self-RNA is prevented by endosomal seclusion of the Toll-like receptors (TLRs) in the dendritic cells (DCs). However, in psoriasis plasmacytoid dendritic cells have been found to be able to sense self-DNA molecules in complex with the endogenous cationic antimicrobial peptide LL37, which are internalized into the endosomal compartments and thus can access TLR9. We investigated whether this endogenous peptide can also interact with extracellular self-RNA and lead to DC activation. We found that LL37 binds self-RNA as well as self-DNA going into an electrostatic interaction; forms micro-aggregates of nano-scale particles protected from …

Cip4 And Src In Promoting The Migration And Invasion Of Breast Cancers, Christina S. Pichot

Dissertations and Theses (Open Access)

Cellular invasion represents a critical early step in the metastatic cascade, and many proteins have been identified as part of an “invasive signature.” The non-receptor tyrosine kinase Src is commonly upregulated in breast cancers, often in conjunction with overexpression of EGFR. Signaling from this pathway stimulates cell proliferation, migration, and invasion and frequently involves proteins that regulate the cytoskeleton. My data demonstrates that inhibition of Src, using the small-molecule inhibitor dasatinib, impairs cellular migration and invasion. Furthermore, Src inhibition sensitizes the cells to the effects of the chemotherapeutic doxorubicin resulting in dramatic, synergistic inhibition of proliferation with combination treatments. The …

Role Of Cd4+Cd25+ Regulatory T Lymphocytes In Experimental Toxoplasmosis, Sanjay Varikuti

Masters Theses & Specialist Projects

Toxoplasmosis is an important cause of congenital disease, and it is one of the most common opportunistic infections in patients with acquired immunodeficiency syndrome. The need for a reliable experimental model of this infection is crucial not only for achieving a better understanding of the patho-physiology of the disease, but also for developing better methods for evaluating new therapeutic regimens. The purpose of the present study was to investigate the role of CD4+CD25+ T regulatory lymphocytes in mice infected with Toxoplasma gondii. T regulatory (Treg) cells have been shown to play an important role in our immune system in …

The Effect Of Endothelin-1 On The Expression Of Cdk Inhibitors P21 & P27 In Bovine Corneal Endothelial Cells, Lakshmi Reddy Bollu

Masters Theses & Specialist Projects

Mammalian corneal endothelial cells are considered to be non-proliferative due to the arrest of cells at the G1 phase of the cell cycle. The purpose of this study was to determine whether the down regulation of cyclin dependant kinase inhibitors (p21cip1 and p27kip1) levels by Endothelin-1 (ET-1), would overcome the G1 phase arrest and promote cell cycle progression and proliferation in cultured BCECs (Bovine corneal endothelial cells). BCECs were isolated from bovine corneas and cultured in DMEM supplemented with 10% serum. 5-Bromo 2-deoxy Uridine (BrdU) incorporation was determined in serum starved cultures in 24-well plates as a measure of cell …

Effects Of Estrogen On Muscle Damage In Response To An Acute Resistance Exercise Protocol, Megan R. Wolf

Honors Scholar Theses

Creatine Kinase (CK) is used as a measure of exercise-induced muscle membrane damage. During acute eccentric (muscle lengthening) exercise, muscle sarcolemma, sarcoplasmic reticulum, and Z-lines are damaged, thus causing muscle proteins and enzymes to leak into the interstitial fluid.

Strenuous eccentric exercise produces an elevation of oxygen free radicals, which further increases muscle damage. Muscle soreness and fatigue can be attributed to this membrane damage. Estradiol, however, may preserve membrane stability post-exercise (Brancaccio, Maffulli, & Limongelli, 2007; Carter, Dobridge, & Hackney, 2001; Tiidus, 2001). Because estradiol has a similar structure to Vitamin E, which is known to have antioxidant properties, …

Naloxone's Pentapeptide Binding Site On Filamin A Blocks Mu Opioid Receptor–Gs Coupling And Creb Activation Of Acute Morphine, Hoau-Yan Wang, Lindsay H. Burns

Publications and Research

Chronic morphine causes the mu opioid receptor (MOR) to switch its coupling from Gi/o to Gs, resulting in excitatory signaling via both Gαs and its Gβγ dimer. Ultra-low-dose naloxone (NLX) prevents this switch and attenuates opioid tolerance and dependence. This protective effect is mediated via a high-affinity interaction of NLX to a pentapeptide region in c-terminal filamin A (FLNA), a scaffolding protein interacting with MOR. In organotypic striatal slice cultures, we now show that acute morphine induces a dose-dependent Go-to-Gs coupling switch at 5 and 15 min that resolves by 1 hr. The acute Gs coupling induced by 100 µM …

Novel Role Of Antioxidant-1 (Atox1) As A Copper-Dependent Transcription Factor Involved In Cell Proliferation, S. Itoh, H. W. Kim, O. Nakagawa, K. Ozumi, Susan M. Lessner, H. Aoki, K. Akram, R. D. Mckinney, M. Ushio-Fukai, T. Fukai

Faculty Publications

Copper plays a fundamental role in regulating cell growth. Many types of human cancer tissues have higher copper levels than normal tissues. Copper can also induce gene expression. However, transcription factors that mediate copper-induced cell proliferation have not been identified in mammals. Here we show that antioxidant-1 (Atox1), previously appreciated as a copper chaperone, represents a novel copper-dependent transcription factor that mediates copper-induced cell proliferation. Stimulation of mouse embryonic fibroblasts (MEFs) with copper markedly increased cell proliferation, cyclin D1 expression, and entry into S phase, which were completely abolished in Atox1^-/- MEFs. Promoter analysis and EMSA revealed that copper …

Gene Therapy Using Tet-Repressor System To Modulate Prostate Tumor Microenvironment, Nazita Yousefieh

Theses and Dissertations in Biomedical Sciences

Prostate cancer is the most commonly diagnosed malignancy in men in the United States and is projected to be the third most frequent cause of male cancer-related deaths in 2007 after lung and skin cancers. The initial treatment for prostate cancer at early stages is prostatectomy or radiation, which usually is curative. However, approximately 20% of patients are not cured by such treatments and their cancer recurs, sometimes with long latencies. In other patients prostate cancer is diagnosed only after the cancer has metastasized and there are no effective therapies at this stage. Therefore immunotherapy seems to be a promising …

The Expression And Function Of Ppar And Hif-1 In Human Melanoma, Caroline Mills

Theses, Dissertations and Capstones

The first part of my dissertation focuses on the expression and function of PPARs in human melanoma. I found that the A375 cells were significantly growth inhibited in response to _PGJ2 and troglitazone treatment. HEMn-LP showed significant growth inhibition in response to troglitazone. I found that PPARγ and PPARδ mRNA is present in both the SK-Mel 28 and A375 cells. The relative level of PPARα mRNA expression is highest in SK-Mel 28 cells, ~3 fold higher relative to both the normal human melanocytes and A375 cells. PPARγ protein was ~50% higher in both SK-Mel 28 and A375 cells relative to …

Synthesis And Antifungal Properties Of Alpha-Methoxy And Alpha-Hydroxyl Substituted 4-Thiatetradecanoic Acids, Nestor Carballeira, Rosann O'Neill, Keykavous Parang

Pharmacy Faculty Articles and Research

4-Thiatetradecanoic acid exhibited weak antifungal activities against Candida albicans (ATCC 60193), Cryptococcus neoformans (ATCC 6603 1), and Aspergillus niger (ATCC 16404) (MIC = 4.8-12.7 mM). It has been demonstrated that alpha-methoxylation efficiently blocks P-oxidation and significantly improve the antifungal activities of fatty acids. We examined whether antifungal activity of 4-thiatetradecanoic acid can be improved by a-substitution. The unprecedented (+/-)-2-tiydroxy-4-thiatetradecanoic acid was synthesized in four steps (20% overall yield), while the (+/-)-2-methoxy-4-thiatetradecanoic acid was synthesized in five steps (14% overall yield) starting from 1-decanethiol. The key step in the synthesis was the hydrolysis of a trimethylsilyloxynitrile. In general, the novel (+/-)-2-methoxy-4-thiatetradecanoic …

Linking Ligand-Induced Alterations In Androgen Receptor Structure To Differential Gene Expression: A First Step In The Rational Design Of Selective Androgen Receptor Modulators, Dmitri Kazmin, Tatiana Prytkova, C. Edgar Cook, Russell Wolfinger, Tzu-Ming Chu, David Beratan, J. D. Norris, Ching-Yi Chang, Donald P. Mcdonnell

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We have previously identified a family of novel androgen receptor (AR) ligands that, upon binding, enable AR to adopt structures distinct from that observed in the presence of canonical agonists. In this report, we describe the use of these compounds to establish a relationship between AR structure and biological activity with a view to defining a rational approach with which to identify useful selective AR modulators. To this end, we used combinatorial peptide phage display coupled with molecular dynamic structure analysis to identify the surfaces on AR that are exposed specifically in the presence of selected AR ligands. Subsequently, we …

Biomarkers For Placental Abnormality, Cathal Mccarthy

Doctoral

Obstetrical complications including recurrent miscarriage, pre-eclampsia and intrauterine growth restriction (IUGR) affect 1%-5% of pregnant women (Younis and Samueloff 2003). Dysfunctional trophoblasts, impaired development of spiral arteries, imbalance in systems controlling the dilation and contraction of spiral arteries, placental fibrin clots and intervillous thrombosis are all possible factors that can result in an insufficient placental circulation. The combination of the hypercoagulable state of pregnancy and presence of genetic thrombophilic markets has the potential to induce placental thrombosis and cause placental insufficiency with subsequent obstetrical complications. The initial part of the research work involved examining the relationship between four common genetic …

Telomerase Activity In Human Preimplantation Embryos, Diane Lynne Wright

Theses and Dissertations in Biomedical Sciences

Telomerase, a ribonucleoprotein, has been described as an essential component of highly proliferative cells, which stabilizes the telomeres and avoids cellular senescence. Telomerase has been identified in various embryonic cell stages, hematopoietic cells, and in >85% of tumor tissue biopsies analyzed. The ability to measure the potential to proliferate successfully could provide an objective measure of an embryo's quality. The objectives of this study were to modify the telomeric repeat amplification protocol (TRAP) assay system for increased sensitivity to allow detection of telomerase activity in the single cell of an oocyte and embryo, obtain telomerase activity levels for the oocyte …

Reaction-Diffusion Models Of Cancer Dispersion, Kim Yvette Ward

Mathematics & Statistics Theses & Dissertations

The phenomenological modeling of the spatial distribution and temporal evolution of one-dimensional models of cancer dispersion are studied. The models discussed pertain primarily to the transition of a tumor from an initial neoplasm to the dormant avascular state, i.e. just prior to the vascular state, whenever that may occur. Initiating the study is the mathematical analysis of a reaction-diffusion model describing the interaction between cancer cells, normal cells and growth inhibitor. The model leads to several predictions, some of which are supported by experimental data and clinical observations $\lbrack25\rbrack$. We will examine the effects of additional terms on these characteristics. …

Characterization Of A Novel Prostate Tumor-Associated Antigen, Grayson B. Lipford

Theses and Dissertations in Biomedical Sciences

The murine monoclonal antibodies (MAb) TURP-27 and HNK-1 have been shown to detect antigens that are heavily expressed by benign prostatic hyperplasia (BPH) and carcinoma of the prostate (CaP). Western blot analysis of prostate extracts, showed that MAb TURP-27 and MAb HNK-1 bound glycoproteins of 180, 140, 120, 100, 90 and 69 kDa. Studies have shown that the HNK-1 carbohydrate epitope may be involved in cell adhesion and that it is a component of several characterized adhesion proteins. TURP-27 was found to bind at least three of these adhesion proteins: neural cell adhesion molecules (N-CAM), myelin-associated glycoprotein (MAG) and a …

The Effects Of Glutathione On Human Keratinocyte, Manisha N. Trivedi

Theses and Dissertations in Biomedical Sciences

Cultured human keratinocytes were grown in vitro to assess the effects of glutathione, a thiol, on human keratinocyte proliferation. Single keratinocytes were harvested from newborn (greater than 5 days old) foreskin and were grown in culture flasks such that experiments could be performed in approximately 2 to 3 weeks. In order to evaluate the effects of glutathione (GSH) on keratinocyte growth, experiments were performed to determine the growth curve, plating efficiency, and incorporation of radiolabelled thymidine. Growth studies, performed with different concentrations of glutathione, revealed that 0.065 μM was the most effective concentration when compared to control cell cultures, and …

The Effects Of 712-Dimethylbenz (A) Anthracene On Ovarian Steroidogenesis And Uterine Growth In The Mouse, Jeffrey Lynn Clark

Biological Sciences Theses & Dissertations

It has been previously demonstrated that 7,12-dimethylbenz(a) anthracene (DMBA) is an initiator of ovarian granulosa cell tumors. It is also known that DMBA leads to destruction of primordial oocytes, and that tumor induction may involve the interaction of pituitary gonadotropins. However, the effects of DMBA on ovarian steroidogenesis and uterine growth in relation to the tumorigenic process have not been investigated. Therefore, the present study was conducted to examine these parameters using adult C57Bl/6N mice treated in proestrus and diestrus II with 0.1 ml corn oil with or without 1.5 mg DMBA and killed 44 hours later. The uteri and …