Medical Immunology Commons^™

Potential Roles Of Extracellular Vesicles In The Pathophysiology, Diagnosis, And Treatment Of Autoimmune Diseases., Jing Tian, Giacomo Casella, Yuan Zhang, Abdolmohamad Rostami, Xing Li

Department of Neurology Faculty Papers

Since extracellular vesicles (EVs) were discovered in 1983 in sheep reticulocytes samples, they have gradually attracted scientific attention and become a topic of great interest in the life sciences field. EVs are small membrane particles, released by virtually every cell that carries a variety of functional molecules. Their main function is to deliver messages to the surrounding area in both physiological and pathological conditions. Initially, they were thought to be either cell debris, signs of cell death, or unspecific structures. However, accumulating evidence support a theory that EVs are a universal mechanism of communication. Thanks to their biological characteristics and …

Resistance To Ectromelia Virus Infection Requires Cgas In Bone Marrow-Derived Cells Which Can Be Bypassed With Cgamp Therapy., Eric B. Wong, Brian Montoya, Maria Ferez, Colby Stotesbury, Luis J. Sigal

Department of Microbiology and Immunology Faculty Papers

Cells sensing infection produce Type I interferons (IFN-I) to stimulate Interferon Stimulated Genes (ISGs) that confer resistance to viruses. During lympho-hematogenous spread of the mouse pathogen ectromelia virus (ECTV), the adaptor STING and the transcription factor IRF7 are required for IFN-I and ISG induction and resistance to ECTV. However, it is unknown which cells sense ECTV and which pathogen recognition receptor (PRR) upstream of STING is required for IFN-I and ISG induction. We found that cyclic-GMP-AMP (cGAMP) synthase (cGAS), a DNA-sensing PRR, is required in bone marrow-derived (BMD) but not in other cells for IFN-I and ISG induction and for …

Langerhans Cells Orchestrate The Protective Antiviral Innate Immune Response In The Lymph Node., Eric B. Wong, Brian Montoya, Colby Stotesbury, Maria Ferez, Ren-Huan Xu, Luis J. Sigal

Department of Microbiology and Immunology Faculty Papers

During disseminating viral infections, a swift innate immune response (IIR) in the draining lymph node (dLN) that restricts systemic viral spread is critical for optimal resistance to disease. However, it is unclear how this IIR is orchestrated. We show that after footpad infection of mice with ectromelia virus, dendritic cells (DCs) highly expressing major histocompatibility complex class II (MHC class II^hi DCs), including CD207⁺ epidermal Langerhans cells (LCs), CD103⁺CD207⁺ double-positive dermal DCs (DP-DCs), and CD103⁻CD207⁻ double-negative dermal DCs (DN-DCs) migrate to the dLN from the skin carrying virus. MHC class II^{hi …}

Incorporating B Cell Activating Factor (Baff) Into The Membrane Of Rabies Virus (Rabv) Particles Improves The Speed And Magnitude Of Vaccine-Induced Antibody Responses., Joseph R Plummer, James P Mcgettigan

Department of Microbiology and Immunology Faculty Papers

B cell activating factor (BAFF) is a member of the tumor necrosis factor (TNF) superfamily of cytokines that links innate with adaptive immunity. BAFF signals through receptors on B cells, making it an attractive molecule to potentiate vaccine-induced B cell responses. We hypothesized that a rabies virus (RABV)-based vaccine displaying both antigen and BAFF on the surface of the same virus particle would target antigen-specific B cells for activation and improve RABV-specific antibody responses. To test this hypothesis, we constructed a recombinant RABV-based vector expressing virus membrane-anchored murine BAFF (RABV-ED51-mBAFF). BAFF was incorporated into the RABV particle and determined to …

Antibody Responses Against The Vaccine Antigens Ov-103 And Ov-Ral-2 Are Associated With Protective Immunity To Onchocerca Volvulus Infection In Both Mice And Humans., Parakkal Jovvian George, Jessica A. Hess, Sonia Jain, John B. Patton, Tingting Zhan, Nancy Tricoche, Bin Zhan, Maria Elena Bottazzi, Peter J. Hotez, David Abraham, Sara Lustigman

Department of Microbiology and Immunology Faculty Papers

BACKGROUND: The current strategy for the elimination of onchocerciasis is based on annual or bi-annual mass drug administration with ivermectin. However, due to several limiting factors there is a growing concern that elimination of onchocerciasis cannot be achieved solely through the current strategy. Additional tools are critically needed including a prophylactic vaccine. Presently Ov-103 and Ov-RAL-2 are the most promising vaccine candidates against an Onchocerca volvulus infection.

METHODOLOGY/PRINCIPAL FINDINGS: Protection induced by immunization of mice with the alum-adjuvanted Ov-103 or Ov-RAL-2 vaccines appeared to be antibody dependent since AID-/- mice that could not mount antigen-specific IgG antibody responses were not …

Roles Of Gm-Csf In The Pathogenesis Of Autoimmune Diseases: An Update., Noushin Lotfi, Rodolfo Thome, Nahid Rezaei, Guang-Xian Zhang, Abbas Rezaei, A. M. Rostami, Nafiseh Esmaeil

Department of Neurology Faculty Papers

Granulocyte-macrophage colony-stimulating factor (GM-CSF) was first described as a growth factor that induces the differentiation and proliferation of myeloid progenitors in the bone marrow. GM-CSF also has an important cytokine effect in chronic inflammatory diseases by stimulating the activation and migration of myeloid cells to inflammation sites, promoting survival of target cells and stimulating the renewal of effector granulocytes and macrophages. Because of these pro-cellular effects, an imbalance in GM-CSF production/signaling may lead to harmful inflammatory conditions. In this context, GM-CSF has a pathogenic role in autoimmune diseases that are dependent on cellular immune responses such as multiple sclerosis (MS) …

Rabies-Based Vaccine Induces Potent Immune Responses Against Nipah Virus., Rohan Keshwara, Thomas Shiels, Elena Postnikova, Drishya Kurup, Christoph Wirblich, Reed F. Johnson, Matthias J. Schnell

Department of Microbiology and Immunology Faculty Papers

Nipah Virus (NiV) is a re-emerging zoonotic pathogen in the genus Henipavirus of the Paramyxoviridae family of viruses. NiV is endemic to Bangladesh and Malaysia and is highly fatal to both livestock and humans (human case fatality rate = 74.5%). Currently, there is no approved vaccine against NiV on the market. The goal of this study was to use a recombinant RABV vector expressing NiV glycoprotein (NiV G) to develop a bivalent candidate vaccine against NiV disease and rabies virus (RABV) disease, which is also a significant health burden in the regions where NiV is endemic. The rabies vector is …

Enhancing Natural Killer And Cd8 + T Cell-Mediated Anticancer Cytotoxicity And Proliferation Of Cd8 + T Cells With Hla-E Monospecific Monoclonal Antibodies, Mepur H. Ravindranath, Edward J. Filippone, Asokan Devarajan, Shahab Asgharzadeh

Department of Medicine Faculty Papers

Cytotoxic NK/CD8+ T cells interact with MHC-I ligands on tumor cells through either activating or inhibiting receptors. One of the inhibitory receptors is CD94/NKG2A. The NK/CD8+ T cell cytotoxic capability is lost when tumor-associated human leukocyte antigen, HLA-E, binds the CD94/NKG2A receptor, resulting in tumor progression and reduced survival. Failure of cancer patients to respond to natural killer (NK) cell therapies could be due to HLA-E overexpression in tumor tissues. Preventing the inhibitory receptor-ligand interaction by either receptor- or ligand-specific monoclonal antibodies (mAbs) is an innovative passive immunotherapeutic strategy for cancer. Since receptors and ligands can be monomeric or homo- …

Ripk1 Can Mediate Apoptosis In Addition To Necroptosis During Embryonic Development., Xuhua Zhang, John P. Dowling, Jianke Zhang

Department of Microbiology and Immunology Faculty Papers

RIPK1 has emerged as a key effector in programmed necrosis or necroptosis. This function of RIPK1 is mediated by its protein serine/threonine kinase activity and through the downstream kinase RIPK3. Deletion of RIPK1 prevents embryonic lethality in mice lacking FADD, a signaling adaptor protein required for activation of Caspase 8 in extrinsic apoptotic pathways. This indicates that FADD-mediated apoptosis inhibits RIPK1-dependent necroptosis to ensure successful embryogenesis. However, the molecular mechanism for this critical regulation remains unclear. In the current study, a novel mouse model has been generated, by disrupting a potential caspase cleavage site at aspartic residue (D)324 in RIPK1. …

Tradd Regulates Perinatal Development And Adulthood Survival In Mice Lacking Ripk1 And Ripk3., John P. Dowling, Mohamed Alsabbagh, Christina Del Casale, Zheng-Gang Liu, Jianke Zhang

Department of Microbiology and Immunology Faculty Papers

TRADD is an adaptor for TNFR1-induced apoptosis and NFκB activation. However, TRADD-deficient mice undergo normal development and contain normal lymphoid populations, which contrasts with an embryonic defect in mice lacking FADD, the shared adaptor mediating apoptosis. Recent studies indicate FADD suppresses embryonic necroptosis mediated by RIPK1. TRADD was suggested to also mediate necroptosis. Here we report that targeting TRADD fails to rescue Fadd ^−/− embryos from necroptosis, and ablation of TRADD rescues Ripk1 ^−/− mice from perinatal lethality when RIPK3-mediated necroptosis is disabled. The resulting Ripk1 ^−/− Ripk3 ^−/− Tradd ^−/− mice survive until early adulthood, but die thereafter. A …

Efficacy Of Combination Of Immunotherapies In A Murine In A Murine Squamous Cell Carcinoma Model, E. Correia, C. Portocarrero, U. Rodeck

Phase 1

Introduction: Head and neck squamous cell carcinomas (HNSCCs) are a type of neoplasm found in the epithelium of the oral cavity, oropharynx, nasopharynx, larynx, or hypopharynx. Recent evidence has demonstrated that 70-90% of HNSCC are associated with Human Papillomavirus (HPV), particularly strain 16 producing oncogenic proteins E6/E7. Currently, HNSCCs are treated with surgery, chemotherapy, and radiation, however immunotherapy with immune checkpoint (PD-1) blocking agents promises to improve outcomes in HNSCC.

Objective: This study examined the therapeutic effects of dual and triple combination immunotherapies in a mouse model of HPV-associated HNSCC.

Methods: Treatment modalities included a tumor vaccine (attenuated Listeria monocytogenes …

Quantitative Clinical And Autoimmune Assessments In Stiff Person Syndrome: Evidence For A Progressive Disorder., Goran Rakocevic, Harry Alexopoulos, Marinos C. Dalakas

Department of Neurology Faculty Papers

BACKGROUND: Stiff Person Syndrome (SPS) is an under-diagnosed disorder that affects mobility and the quality of life of affected patients. The aim of the study is to describe the natural history of SPS, the extent of accumulated disability and the associated clinical and immunological features in patients followed for up to 8 years in a single center.

METHODS: Our collective cohort included 57 SPS patients. Additionally, 32 of these patients were examined every 6 months for a two-year period in a longitudinal study protocol, to assess disease progression using quantitative measures of stiffness and heightened sensitivity.

RESULTS: The most frequent …

A Virus-Encoded Type I Interferon Decoy Receptor Enables Evasion Of Host Immunity Through Cell-Surface Binding., Bruno Hernáez, Juan Manuel Alonso-Lobo, Imma Montanuy, Cornelius Fischer, Sascha Sauer, Luis J. Sigal, Noemí Sevilla, Antonio Alcamí

Department of Microbiology and Immunology Faculty Papers

Soluble cytokine decoy receptors are potent immune modulatory reagents with therapeutic applications. Some virus-encoded secreted cytokine receptors interact with glycosaminoglycans expressed at the cell surface, but the biological significance of this activity in vivo is poorly understood. Here, we show the type I interferon binding protein (IFNα/βBP) encoded by vaccinia and ectromelia viruses requires of this cell binding activity to confer full virulence to these viruses and to retain immunomodulatory activity. Expression of a variant form of the IFNα/βBP that inhibits IFN activity, but does not interact with cell surface glycosaminoglycans, results in highly attenuated viruses with a virulence similar …

Development Of Onchocerca Volvulus In Humanized Nsg Mice And Detection Of Parasite Biomarkers In Urine And Serum., John B. Patton, Sasisekhar Bennuru, Mark L. Eberhard, Jessica A. Hess Ligas, April R. Torigian, Sara Lustigman, Thomas B. Nutman, David Abraham

Department of Microbiology and Immunology Faculty Papers

BACKGROUND: The study of Onchocerca volvulus has been limited by its host range, with only humans and non-human primates shown to be susceptible to the full life cycle infection. Small animal models that support the development of adult parasites have not been identified.

METHODOLOGY/PRINCIPAL FINDINGS: We hypothesized that highly immunodeficient NSG mice would support the survival and maturation of O. volvulus and alteration of the host microenvironment through the addition of various human cells and tissues would further enhance the level of parasite maturation. NSG mice were humanized with: (1) umbilical cord derived CD34+ stem cells, (2) fetal derived liver, …

Distinct Role Of Il-27 In Immature And Lps-Induced Mature Dendritic Cell-Mediated Development Of Cd4, Fang Zhou, Guang-Xian Zhang, A. M. Rostami

Department of Neurology Faculty Papers

Interleukin-27 (IL-27) plays an important role in regulation of anti-inflammatory responses and autoimmunity; however, the molecular mechanisms of IL-27 in modulation of immune tolerance and autoimmunity have not been fully elucidated. Dendritic cells (DCs) play a central role in regulating immune responses mediated by innate and adaptive immune systems, but regulatory mechanisms of DCs in CD4⁺ T cell-mediated immune responses have not yet been elucidated. Here we show that IL-27 treated mature DCs induced by LPS inhibit immune tolerance mediated by LPS-stimulated DCs. IL-27 treatment facilitates development of the CD4⁺ CD127⁺3G11⁺ regulatory T cell subset …

Role Of The Fractalkine Receptor In Cns Autoimmune Inflammation: New Approach Utilizing A Mouse Model Expressing The Human Cx3cr1, Sandra M. Cardona, Sangwon V. Kim, Kaira A. Church, Vanessa O. Torres, Ian A. Cleary, Andrew S. Mendiola, Stephen P. Saville, Stephanie S. Watowich, Jan Parker-Thornburg, Alejandro Soto-Ospina, Pedronel Araque, Richard M. Ransohoff, Astrid E. Cardona

Department of Microbiology and Immunology Faculty Papers

Multiple sclerosis (MS), an inflammatory demyelinating disease of the central nervous system (CNS) is the leading cause of non-traumatic neurological disability in young adults. Immune mediated destruction of myelin and oligodendrocytes is considered the primary pathology of MS, but progressive axonal loss is the major cause of neurological disability. In an effort to understand microglia function during CNS inflammation, our laboratory focuses on the fractalkine/CX3CR1 signaling as a regulator of microglia neurotoxicity in various models of neurodegeneration. Fractalkine (FKN) is a transmembrane chemokine expressed in the CNS by neurons and signals through its unique receptor CX3CR1 present in microglia. During …

Polymicrobial Sepsis Influences Nk-Cell-Mediated Immunity By Diminishing Nk-Cell-Intrinsic Receptor-Mediated Effector Responses To Viral Ligands Or Infections., Isaac J. Jensen, Christina S. Winborn, Micaela G. Fosdick, Peng Shao, Mikaela M. Tremblay, Qiang Shan, Sandeep Kumar Tripathy, Christopher M. Snyder, Hai-Hui Xue, Thomas S. Griffith, Jon C. Houtman, Vladimir P. Badovinac

Department of Microbiology and Immunology Faculty Papers

The sepsis-induced cytokine storm leads to severe lymphopenia and reduced effector capacity of remaining/surviving cells. This results in a prolonged state of immunoparalysis, that contributes to enhanced morbidity/mortality of sepsis survivors upon secondary infection. The impact of sepsis on several lymphoid subsets has been characterized, yet its impact on NK-cells remains underappreciated-despite their critical role in controlling infection(s). Here, we observed numerical loss of NK-cells in multiple tissues after cecal-ligation-and-puncture (CLP)-induced sepsis. To elucidate the sepsis-induced lesions in surviving NK-cells, transcriptional profiles were evaluated and indicated changes consistent with impaired effector functionality. A corresponding deficit in NK-cell capacity to produce …

Carnosol Modulates Th17 Cell Differentiation And Microglial Switch In Experimental Autoimmune Encephalomyelitis, Xing Li, Li Zhao, Juan-Juan Han, Fei Zhang, Shuai Liu, Lin Zhu, Zhe-Zhi Wang, Guang-Xian Zhang, Yuan Zhang

Department of Neurology Faculty Papers

Medicinal plants as a rich pool for developing novel small molecule therapeutic medicine have been used for thousands of years. Carnosol as a bioactive diterpene compound originated from Rosmarinus officinalis (Rosemary) and Salvia officinalis, herbs extensively applied in traditional medicine for the treatment of multiple autoimmune diseases (1). In this study, we investigated the therapeutic effects and molecule mechanism of carnosol in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Carnosol treatment significantly alleviated clinical development in the myelin oligodendrocyte glycoprotein (MOG35–55) peptide-induced EAE model, markedly decreased inflammatory cell infiltration into the central nervous system and reduced …

Endomembrane-Associated Pre-Embedding Immunogold Labeling, Zuzana Nichtova, Celia Fernandez-Sanz, A. Bartok, Sergio De La Fuente, György Hajnóczky, Shey-Shing Sheu, György Csordás

Department of Pathology, Anatomy, and Cell Biology Posters

Aim

To optimize the pre-embedding IG in stable cell lines and primary adult cardiomyocytes to get the most effective visualization of endomembrane/associated proteins: endo/sarcoplasmic reticulum Ca2+ release channels IP3 receptors and ryanodine receptors (IP3R, and RyR2) and the mitochondrial fission protein Drp1.

With Some Risk-Taking And Luck: A Veterinarian's Adventures In Viral Immunology., Luis J. Sigal

Department of Microbiology and Immunology Faculty Papers

No abstract provided.

Cd8+ T-Cell Responses In Vaccination: Reconsidering Targets And Function In The Context Of Chronic Antigen Stimulation, Gabriela L. Cosma, Laurence Eisenlohr

Department of Microbiology and Immunology Faculty Papers

Cytotoxic CD8 T cells play important roles in eliminating infected and transformed cells. Owing to their potential for therapeutic applications, significant efforts are dedicated toward developing CD8 T cell-based vaccines. Thus far, CD8 T-cell vaccination strategies have had limited success therapeutically in contrast to those targeting antibody-based immunity. However, if the current challenges and gaps in the understanding of T-cell biology are overcome, the full potential of rational CD8 T-cell vaccine design might be realized. Here, we review recent progress in this direction, focusing on target selection and maintenance of function in the settings of chronic infections and cancers.

Limited Immune Surveillance In Lymphoid Tissue By Cytolytic Cd4+ T Cells During Health And Hiv Disease., Marcus Buggert, Son Nguyen, Laura M. Mclane, Maria Steblyanko, Nadia Anikeeva, Dominic Paquin-Proulx, Perla M Del Rio Estrada, Yuria Ablanedo-Terrazas, Kajsa Noyan, Morgan A. Reuter, Korey Demers, Johan K. Sandberg, Michael A. Eller, Hendrik Streeck, Marianne Jansson, Piotr Nowak, Anders Sönnerborg, David H. Canaday, Ali Naji, E. John Wherry, Merlin L. Robb, Steven G Deeks, Gustavo Reyes-Teran, Yuri Sykulev, Annika C. Karlsson, Michael R. Betts

Department of Medical Oncology Faculty Papers

CD4+ T cells subsets have a wide range of important helper and regulatory functions in the immune system. Several studies have specifically suggested that circulating effector CD4+ T cells may play a direct role in control of HIV replication through cytolytic activity or autocrine β-chemokine production. However, it remains unclear whether effector CD4+ T cells expressing cytolytic molecules and β-chemokines are present within lymph nodes (LNs), a major site of HIV replication. Here, we report that expression of β-chemokines and cytolytic molecules are enriched within a CD4+ T cell population with high levels of the T-box transcription factors T-bet and …

Onchocerca Volvulus: The Road From Basic Biology To A Vaccine., Sara Lustigman, Benjamin L. Makepeace, Thomas R. Klei, Simon A. Babayan, Peter Hotez, David Abraham, Maria Elena Bottazzi

Department of Microbiology and Immunology Faculty Papers

Human onchocerciasis - commonly known as river blindness - is one of the most devastating yet neglected tropical diseases, leaving many millions in sub-Saharan Africa blind and/or with chronic disabilities. Attempts to eliminate onchocerciasis, primarily through the mass drug administration of ivermectin, remains challenging and has been heightened by the recent news that drug-resistant parasites are developing in some populations after years of drug treatment. Needed, and needed now, in the fight to eliminate onchocerciasis are new tools, such as preventive and therapeutic vaccines. This review summarizes the progress made to advance the onchocerciasis vaccine from the research laboratory into …

Taking Control: Reorganization Of The Host Cytoskeleton By Chlamydia., Jordan Wesolowski, Fabienne Paumet

Department of Microbiology and Immunology Faculty Papers

Both actin and microtubules are major cytoskeletal elements in eukaryotic cells that participate in many cellular processes, including cell division and motility, vesicle and organelle movement, and the maintenance of cell shape. Inside its host cell, the human pathogen Chlamydia trachomatis manipulates the cytoskeleton to promote its survival and enhance its pathogenicity. In particular, Chlamydia induces the drastic rearrangement of both actin and microtubules, which is vital for its entry, inclusion structure and development, and host cell exit. As significant progress in Chlamydia genetics has greatly enhanced our understanding of how this pathogen co-opts the host cytoskeleton, we will discuss …

Induction Of Peripheral Tolerance In Ongoing Autoimmune Inflammation Requires Interleukin 27 Signaling In Dendritic Cells, Rodolfo Thome, Jason N. Moore, Elisabeth R. Mari, Javad Rasouli

Department of Neurology Faculty Papers

Peripheral tolerance to autoantigens is induced via suppression of self-reactive lymphocytes, stimulation of tolerogenic dendritic cells (DCs) and regulatory T (Treg) cells. Interleukin (IL)-27 induces tolerogenic DCs and Treg cells; however, it is not known whether IL-27 is important for tolerance induction. We immunized wild-type (WT) and IL-27 receptor (WSX-1) knockout mice with MOG_35-55 for induction of experimental autoimmune encephalomyelitis and intravenously (i.v.) injected them with MOG_35-55 after onset of disease to induce i.v. tolerance. i.v. administration of MOG^35-55 reduced disease severity in WT mice, but was ineffective in Wsx^-/- mice. IL-27 signaling in DCs was …

April:Taci Axis Is Dispensable For The Immune Response To Rabies Vaccination., Shannon L. Haley, Evgeni P. Tzvetkov, Andrew G. Lytle, Kishore R. Alugupalli, Joseph R. Plummer, James P. Mcgettigan

Department of Microbiology and Immunology Faculty Papers

There is significant need to develop a single-dose rabies vaccine to replace the current multi-dose rabies vaccine regimen and eliminate the requirement for rabies immune globulin in post-exposure settings. To accomplish this goal, rabies virus (RABV)-based vaccines must rapidly activate B cells to secrete antibodies which neutralize pathogenic RABV before it enters the CNS. Increased understanding of how B cells effectively respond to RABV-based vaccines may improve efforts to simplify post-exposure prophylaxis (PEP) regimens. Several studies have successfully employed the TNF family cytokine a proliferation-inducing ligand (APRIL) as a vaccine adjuvant. APRIL binds to the receptors TACI and B cell …

Metabolite Profiling Of Infection-Associated Metabolic Markers Of Onchocerciasis., Sasisekhar Bennuru, Sara Lustigman, David Abraham, Thomas B. Nutman

Department of Microbiology and Immunology Faculty Papers

The global efforts for onchocerciasis elimination may require additional tools (safe micro and macrofilaricidal drugs, vaccines and biomarkers) as elimination efforts move toward the "end game". Efforts toward the identification of suitable biomarkers have focused on specific protein(s) and/or nucleic acids, but metabolites present an alternative option as they have limited half-lives and are the result of combinatorial effects. In comparison to previously used methodology of LC-MS for metabolomic approaches, we used a non-targeted capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS) to analyze the serum metabolic profiles of Ov-infected and -uninfected individuals (n=20). We identified 286 known metabolites (167 in the …

The 11s Proteasomal Activator Regγ Impacts Polyglutamine-Expanded Androgen Receptor Aggregation And Motor Neuron Viability Through Distinct Mechanisms., Jill M. Yersak, Heather L. Montie, Erica S. Chevalier-Larsen, Yuhong Liu, Lan Huang, Martin Rechsteiner, Diane E. Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Spinal and bulbar muscular atrophy (SBMA) is caused by expression of a polyglutamine (polyQ)-expanded androgen receptor (AR). The inefficient nuclear proteasomal degradation of the mutant AR results in the formation of nuclear inclusions containing amino-terminal fragments of the mutant AR. PA28γ (also referred to as REGγ) is a nuclear 11S-proteasomal activator with limited proteasome activation capabilities compared to its cytoplasmic 11S (PA28α, PA28β) counterparts. To clarify the role of REGγ in polyQ-expanded AR metabolism, we carried out genetic and biochemical studies in cell models of SBMA. Overexpression of REGγ in a PC12 cell model of SBMA increased polyQ-expanded AR aggregation …

Chlamydia Hijacks Arf Gtpases To Coordinate Microtubule Posttranslational Modifications And Golgi Complex Positioning., Jordan Wesolowski, Mary M. Weber, Agata Nawrotek, Cheryl A. Dooley, Mike Calderon, Claudette M. St Croix, Ted Hackstadt, Jacqueline Cherfils, Fabienne Paumet

Department of Microbiology and Immunology Faculty Papers

The intracellular bacterium Chlamydia trachomatis develops in a parasitic compartment called the inclusion. Posttranslationally modified microtubules encase the inclusion, controlling the positioning of Golgi complex fragments around the inclusion. The molecular mechanisms by which Chlamydia coopts the host cytoskeleton and the Golgi complex to sustain its infectious compartment are unknown. Here, using a genetically modified Chlamydia strain, we discovered that both posttranslationally modified microtubules and Golgi complex positioning around the inclusion are controlled by the chlamydial inclusion protein CT813/CTL0184/InaC and host ARF GTPases. CT813 recruits ARF1 and ARF4 to the inclusion membrane, where they induce posttranslationally modified microtubules. Similarly, both …

Opinion: Inhibition Of Blood-Brain Barrier Repair As A Mechanism In Hiv-1 Disease., Monique E. Maubert, Brian Wigdahl, Michael R. Nonnemacher

Kimmel Cancer Center Papers, Presentations, and Grand Rounds

No abstract provided.