Immune System Diseases Commons^™

Partial Post-Exposure Protection By Topical Inserts Containing Tenofovir Alafenamide Fumarate/Elvitegravir In A Macaque Model Of Rectal Simian Hiv (Shiv) Infection, Natalia Makarova, Tyana Singletary, M. Melissa Peet, Kristen Kelley, Ryan Johnson, Vivek Agrahari, Maria Mendoza, Yi Pan, Walid Heneine, Meredith R. Clark, J. Gerardo García Lerma, Gustavo F. Doncel, James W. Smith

CONRAD Publications

On-demand topical inserts for HIV prevention may be a good option for people who have a low frequency of sexual activity. We recently demonstrated in a preclinical macaque model that rectal application of inserts containing tenofovir alafenamide fumarate (TAF) and elvitegravir (EVG) conferred protection against SHIV infection (93% efficacy) when applied as pre-exposure prophylaxis 4 hours before SHIV exposure. Here, we show that the same inserts provide significant postexposure protection (82.9% efficacy) when applied 4 hours after SHIV exposure. Our findings further support the ongoing clinical development of TAF/EVG inserts for on-demand HIV prevention.

Inhibition Of Histone Demethylase Lsd1 Suppresses Cd47 Expression And Enhances Efficacy Of Cd47 Blockade In Breast Cancer, Fengjie Jiang, Yu Shen, Bing Li, Michael Henry, Nancy Davidson, Yi Huang

Department of Biomedical and Translational Sciences Faculty Publications

Background CD47 functions as a “don’t eat me” checkpoint, inhibiting macrophage-mediated phagocytosis in triple-negative breast cancer (TNBC). While anti-CD47 therapies can restore immune surveillance, their efficacy in TNBC is often limited by immune evasion and drug development challenges.

Methods We investigated the crosstalk between the histone demethylase lysine-specific demethylase 1 (LSD1) and CD47 signaling in TNBC using in silico datasets, isogenic cell lines, conditional BRCA1 knockout models, and syngeneic mouse models. Techniques such as immunohistochemistry, multiplex immunofluorescence, immunoprecipitation, protein ubiquitination, chromatin immunoprecipitation, chemotaxis, flow cytometry, and phagocytosis assays were employed to examine the epigenetic regulation of CD47 by LSD1 and …

Zika Virus Ns1 Drives Tunneling Nanotube Formation For Mitochondrial Transfer And Stealth Transmission In Trophoblasts, Rafael T Michita, Long B Tran, Steven J Bark, Deepak Kumar, Shay A Toner, Joyce Jose, Indira U Mysorekar, Anoop Narayanan

Faculty, Staff and Students Publications

Zika virus (ZIKV) is unique among orthoflaviviruses in its vertical transmission capacity in humans, yet the underlying mechanisms remain incompletely understood. Here, we show that ZIKV induces tunneling nanotubes (TNTs) in placental trophoblasts which facilitate transfer of viral particles, proteins, mitochondria, and RNA to neighboring uninfected cells. TNT formation is driven exclusively via ZIKV non-structural protein 1 (NS1). Specifically, the N-terminal 1-50 amino acids of membrane-bound ZIKV NS1 are necessary for triggering TNT formation in host cells. Trophoblasts infected with TNT-deficient ZIKV

Tfeb Safeguards Trophoblast Syncytialization In Humans And Mice, Wanshan Zheng, Yue Zhang, Peiqun Xu, Zexin Wang, Xuan Shao, Chunyan Chen, Han Cai, Yinan Wang, Ming-An Sun, Wenbo Deng, Fan Liu, Jinhua Lu, Xueqin Zhang, Dunjin Cheng, Indira U Mysorekar, Haibin Wang, Yan-Ling Wang, Xiaoqian Hu, Bin Cao

Faculty, Staff and Students Publications

The formation of multinucleated syncytiotrophoblast (STB) through cell fusion of cytotrophoblast, also termed syncytialization, ensures the proper placental structure and functions. Nutrient insufficiency and inactivation of the mechanistic target of rapamycin complex 1 (mTORC1) in trophoblasts have been shown to enhance STB formation; however, the underlying mechanism remains elusive. Here, we showed that the deficiency of a mTORC1 downstream transcriptional factor, TFEB, significantly impaired STB formation in human trophoblasts and knock-out mice. TFEB conferred direct transcriptional activation of the fusogen ERVFRD-1 and thereby promoted trophoblast syncytialization. Additionally, TFEB expression positively correlated with the reinforced trophoblast syncytialization in human fetal growth …

Downregulation Of Mirlet7 Mirna Family Promotes Tc17 Differentiation And Emphysema Via De-Repression Of Rorγt, Phillip A Erice, Xinyan Huang, Matthew J Seasock, Matthew J Robertson, Hui-Ying Tung, Melissa A Perez-Negron, Shivani L Lotlikar, David B Corry, Farrah Kheradmand, Antony Rodriguez

Faculty, Staff and Students Publications

Environmental air irritants including nanosized carbon black (nCB) can drive systemic inflammation, promoting chronic obstructive pulmonary disease (COPD) and emphysema development. The let-7 microRNA (Mirlet7 miRNA) family is associated with IL-17-driven T cell inflammation, a canonical signature of lung inflammation. Recent evidence suggests the Mirlet7 family is downregulated in patients with COPD, however, whether this repression conveys a functional consequence on emphysema pathology has not been elucidated. Here, we show that overall expression of the Mirlet7 clusters, Mirlet7b/Mirlet7c2 and Mirlet7a1/Mirlet7f1/Mirlet7d, are reduced in the lungs and T cells of smokers with emphysema as well as in mice with …

D-Mannose Reduces Cellular Senescence And Nlrp3/Gasdermind/Il-1Β-Driven Pyroptotic Uroepithelial Cell Shedding In The Murine Bladder, Chetanchandra S Joshi, Arnold M Salazar, Caihong Wang, Marianne M Ligon, Rayvanth R Chappidi, Bisiayo E Fashemi, Paul A Felder, Amy Mora, Sandra L Grimm, Cristian Coarfa, Indira U Mysorekar

Faculty, Staff and Students Publications

Aging is a risk factor for disease via increased susceptibility to infection, decreased ability to maintain homeostasis, inefficiency in combating stress, and decreased regenerative capacity. Multiple diseases, including urinary tract infection (UTI), are more prevalent with age; however, the mechanisms underlying the impact of aging on the urinary tract mucosa and the correlation between aging and disease remain poorly understood. Here, we show that, relative to young (8-12 weeks) mice, the urothelium of aged (18-24 months) female mice accumulates large lysosomes with reduced acid phosphatase activity and decreased overall autophagic flux in the aged urothelium, indicative of compromised cellular homeostasis. …

The Dna Glycosylase Neil2 Is Protective During Sars-Cov-2 Infection, Nisha Tapryal, Anirban Chakraborty, Kaushik Saha, Azharul Islam, Lang Pan, Koa Hosoki, Ibrahim M Sayed, Jason M Duran, Joshua Alcantara, Vanessa Castillo, Courtney Tindle, Altaf H Sarker, Maki Wakamiya, Victor J Cardenas, Gulshan Sharma, Laura E Crotty Alexander, Sanjiv Sur, Debashis Sahoo, Gourisankar Ghosh, Soumita Das, Pradipta Ghosh, Istvan Boldogh, Tapas K Hazra

Faculty, Staff and Students Publications

SARS-CoV-2 infection-induced aggravation of host innate immune response not only causes tissue damage and multiorgan failure in COVID-19 patients but also induces host genome damage and activates DNA damage response pathways. To test whether the compromised DNA repair capacity of individuals modulates the severity of COVID-19 infection, we analyze DNA repair gene expression in publicly available patient datasets and observe a lower level of the DNA glycosylase NEIL2 in the lungs of severely infected COVID-19 patients. This observation of lower NEIL2 levels is further validated in infected patients, hamsters and ACE2 receptor-expressing human A549 (A549-ACE2) cells. Furthermore, delivery of recombinant …

Toll-Like Receptor 4 And Cd11b Expressed On Microglia Coordinate Eradication Of Candida Albicans Cerebral Mycosis, Yifan Wu, Shuqi Du, Lynn H Bimler, Kelsey E Mauk, Léa Lortal, Nessim Kichik, James S Griffiths, Radim Osicka, Lizhen Song, Katherine Polsky, Lydia Kasper, Peter Sebo, Jill Weatherhead, J Morgan Knight, Farrah Kheradmand, Hui Zheng, Jonathan P Richardson, Bernhard Hube, Julian R Naglik, David B Corry

Faculty, Staff and Students Publications

The fungal pathogen Candida albicans is linked to chronic brain diseases such as Alzheimer's disease (AD), but the molecular basis of brain anti-Candida immunity remains unknown. We show that C. albicans enters the mouse brain from the blood and induces two neuroimmune sensing mechanisms involving secreted aspartic proteinases (Saps) and candidalysin. Saps disrupt tight junction proteins of the blood-brain barrier (BBB) to permit fungal brain invasion. Saps also hydrolyze amyloid precursor protein (APP) into amyloid β (Aβ)-like peptides that bind to Toll-like receptor 4 (TLR4) and promote fungal killing in vitro while candidalysin engages the integrin CD11b (Mac-1) on microglia. …

Loss Of Stearoyl-Coa Desaturase 2 Disrupts Inflammatory Response In Macrophages, Joseph B Lin, Amy Mora, Tzu Jui Wang, Andrea Santeford, Darksha Usmani, Marianne M Ligon, Indira U Mysorekar, Rajendra S Apte

Faculty, Staff and Students Publications

Macrophages are innate immune cells that patrol tissues and are the first responders to detect infection. They orchestrate the host immune response in eliminating invading pathogens and the subsequent transition from inflammation to tissue repair. Macrophage dysfunction contributes to age-related pathologies, including low-grade inflammation in advanced age that is termed "inflammaging." Our laboratory has previously identified that macrophage expression of a fatty acid desaturase, stearoyl-CoA desaturase 2 (SCD2), declines with age. Herein, we delineate the precise cellular effects of SCD2 deficiency in murine macrophages. We found that deletion of

Contribution Of Adaptive Immunity To Human Copd And Experimental Models Of Emphysema, Farrah Kheradmand, Yun Zhang, David B Corry

Faculty, Staff and Students Publications

The pathophysiology of chronic obstructive pulmonary disease (COPD) and the undisputed role of innate immune cells in this condition have dominated the field in the basic research arena for many years. Recently, however, compelling data suggesting that adaptive immune cells may also contribute to the progressive nature of lung destruction associated with COPD in smokers have gained considerable attention. The histopathological changes in the lungs of smokers can be limited to the large or small airways, but alveolar loss leading to emphysema, which occurs in some individuals, remains its most significant and irreversible outcome. Critically, however, the question of why …

Effects Of Aging On Urinary Tract Epithelial Homeostasis And Immunity, Marianne M Ligon, Chetanchandra S Joshi, Bisiayo E Fashemi, Arnold M Salazar, Indira U Mysorekar

Faculty, Staff and Students Publications

A global increase in older individuals creates an increasing demand to understand numerous healthcare challenges related to aging. This population is subject to changes in tissue physiology and the immune response network. Older individuals are particularly susceptible to infectious diseases, with one of the most common being urinary tract infections (UTIs). Postmenopausal and older women have the highest risk of recurrent UTIs (rUTIs); however, why rUTIs become more frequent after menopause and during old age is incompletely understood. This increased susceptibility and severity among older individuals may involve functional changes to the immune system with age. Aging also has substantial …

Intrapulmonary Administration Of Purified Neil2 Abrogates Nf-Κb-Mediated Inflammation, Nisha Tapryal, Shandy Shahabi, Anirban Chakraborty, Koa Hosoki, Maki Wakamiya, Gobinda Sarkar, Gulshan Sharma, Victor J Cardenas, Istvan Boldogh, Sanjiv Sur, Gourisankar Ghosh, Tapas K Hazra

Faculty, Staff and Students Publications

Aberrant or constitutive activation of nuclear factor kappa B (NF-κB) contributes to various human inflammatory diseases and malignancies via the upregulation of genes involved in cell proliferation, survival, angiogenesis, inflammation, and metastasis. Thus, inhibition of NF-κB signaling has potential for therapeutic applications in cancer and inflammatory diseases. We reported previously that Nei-like DNA glycosylase 2 (NEIL2), a mammalian DNA glycosylase, is involved in the preferential repair of oxidized DNA bases from the transcriptionally active sequences via the transcription-coupled base excision repair pathway. We have further shown that Neil2-null mice are highly sensitive to tumor necrosis factor α (TNFα)- and lipopolysaccharide-induced …

Combined Effects Of Hyperglycemic Conditions And Hiv-1 Nef: A Potential Model For Induced Hiv Neuropathogenesis., Edward A Acheampong, Cassandra Roschel, Muhammad Mukhtar, Alagarsamy Srinivasan, Mohammad Rafi, Roger J Pomerantz, Zahida Parveen

Department of Neurology Faculty Papers

Hyperglycemic conditions associated with diabetes mellitus (DM) or with the use of antiretroviral therapy may increase the risk of central nervous system (CNS) disorders in HIV-1 infected patients. In support of this hypothesis, we investigated the combined effects of hyperglycemic conditions and HIV-1 accessory protein Nef on the CNS using both in vitro and in vivo models. Astrocytes, the most abundant glial cell type required for normal synaptic transmission and other functions were selected for our in vitro study. The results show that in vitro hyperglycemic conditions enhance the expression of proinflammatory cytokines including caspase-3, complement factor 3 (C3), and …

Anti-Gag Cytolytic T Lymphocytes Specific For An Alternative Translational Reading Frame-Derived Epitope And Resistance Versus Susceptibility To Retrovirus-Induced Murine Aids In F1 Mice, Shawn-Marie Mayrand, Patricia A. Healy, Bruce E. Torbett, William R. Green

Dartmouth Scholarship

Murine AIDS (MAIDS) develops in susceptible mouse strains after infection with the LP-BM5 murine leukemia virus complex that contains causative defective, and ecotropic helper, retroviruses. We previously demonstrated that the MAIDSresistant H-2d strains BALB/cByJ and C57BL/KsJ generate MHC class I (Kd ) restricted virus-specific CD81 cytolytic T lymphocytes (CTLs) that lyse cells expressing either defective or ecotropic gag proteins. In contrast, the congenic BALB.B and closely related C57BL/6J MAIDS-susceptible H-2b strains were unable to serve as a source of gag-specific CTLs (Schwarz and Green, 1994), suggesting that anti-gag CTLs might provide a basis for resistance to MAIDS. Although its susceptibility …