Digital Commons Network^™

The Neurotoxin Dsp-4 Dysregulates The Locus Coeruleus-Norepinephrine System And Recapitulates Molecular And Behavioral Aspects Of Prodromal Neurodegenerative Disease, Alexa F. Iannitelli, Michael A. Kelberman, Daniel J. Lustberg, Anu Korukonda, Katharine E. Mccann, Bernard Mulvey, Arielle Segal, L Cameron Liles, Steven A. Sloan, Joseph D. Dougherty, David Weinshenker

2020-Current year OA Pubs

The noradrenergic locus coeruleus (LC) is among the earliest sites of tau and α-synuclein pathology in Alzheimer's disease (AD) and Parkinson's disease (PD), respectively. The onset of these pathologies coincides with loss of noradrenergic fibers in LC target regions and the emergence of prodromal symptoms including sleep disturbances and anxiety. Paradoxically, these prodromal symptoms are indicative of a noradrenergic hyperactivity phenotype, rather than the predicted loss of norepinephrine (NE) transmission following LC damage, suggesting the engagement of complex compensatory mechanisms. Because current therapeutic efforts are targeting early disease, interest in the LC has grown, and it is critical to identify …

Loss Of Ubiquitin-Specific Peptidase 18 Destabilizes 14-3-3Ζ Protein And Represses Lung Cancer Metastasis, Zibo Chen, Lin Zheng, Yulong Chen, Xiuxia Liu, Masanori Kawakami, Lisa Maria Mustachio, Jason Roszik, Katherine V Ferry-Galow, Ralph E Parchment, Xin Liu, Thorkell Andresson, Gerard Duncan, Jonathan M Kurie, Jaime Rodriguez-Canales, Xi Liu, Ethan Dmitrovsky

Faculty, Staff and Student Publications

Cancer metastasis is a major cause of cancer-related mortality. Strategies to reduce metastases are needed especially in lung cancer, the most common cause of cancer mortality. We previously reported increased ubiquitin-specific peptidase 18 (USP18) expression in lung and other cancers. Engineered reduction of USP18 expression repressed lung cancer growth and promoted apoptosis. This deubiquitinase (DUB) stabilized targeted proteins by removing the complex interferon-stimulated gene 15 (ISG15). This study explores if the loss of USP18 reduced lung cancer metastasis. USP18 knock-down in lung cancer cells was independently achieved using small hairpin RNAs (shRNAs) and small interfering RNAs (siRNAs). USP18 knock-down reduced …

Polycystin-1 Is A Crucial Regulator Of Bin1 Expression And T-Tubule Remodeling Associated With The Development Of Dilated Cardiomyopathy, Magda C Díaz-Vesga, Raúl Flores-Vergara, Jaime A Riquelme, Marcelo Llancaqueo, Gina Sánchez, Cecilia Vergara, Luis Michea, Paulina Donoso, Andrew F G Quest, Ivonne Olmedo, Zully Pedrozo

Faculty, Staff and Student Publications

Cardiomyopathy is commonly observed in patients with autosomal dominant polycystic kidney disease (ADPKD), even when they have normal renal function and arterial pressure. The role of cardiomyocyte polycystin-1 (PC1) in cardiovascular pathophysiology remains unknown. PC1 is a potential regulator of BIN1 that maintains T-tubule structure, and alterations in BIN1 expression induce cardiac pathologies. We used a cardiomyocyte-specific PC1-silenced (PC1-KO) mouse model to explore the relevance of cardiomyocyte PC1 in the development of heart failure (HF), considering reduced BIN1 expression induced T-tubule remodeling as a potential mechanism. PC1-KO mice exhibited an impairment of cardiac function, as measured by echocardiography, but no …

Diverse Monogenic Subforms Of Human Spermatogenic Failure, Liina Nagirnaja, Wu-Lin Charng, Christina A Gurnett, Kenan R Omurtag, Et Al.

2020-Current year OA Pubs

Non-obstructive azoospermia (NOA) is the most severe form of male infertility and typically incurable. Defining the genetic basis of NOA has proven challenging, and the most advanced classification of NOA subforms is not based on genetics, but simple description of testis histology. In this study, we exome-sequenced over 1000 clinically diagnosed NOA cases and identified a plausible recessive Mendelian cause in 20%. We find further support for 21 genes in a 2-stage burden test with 2072 cases and 11,587 fertile controls. The disrupted genes are primarily on the autosomes, enriched for undescribed human "knockouts", and, for the most part, have …

Glutamine Produces Ammonium To Tune Lysosomal Ph And Regulate Lysosomal Function, Jian Xiong, Thi Thu Trang Luu, Kartik Venkatachalam, Guangwei Du, Michael X Zhu

Faculty, Staff and Student Publications

Glutamine is one of the most abundant amino acids in the cell. In mitochondria, glutaminases 1 and 2 (GLS1/2) hydrolyze glutamine to glutamate, which serves as the precursor of multiple metabolites. Here, we show that ammonium generated during GLS1/2-mediated glutaminolysis regulates lysosomal pH and in turn lysosomal degradation. In primary human skin fibroblasts BJ cells and mouse embryonic fibroblasts, deprivation of total amino acids for 1 h increased lysosomal degradation capacity as shown by the increased turnover of lipidated microtubule-associated proteins 1A/1B light chain 3B (LC3-II), several autophagic receptors, and endocytosed DQ-BSA. Removal of glutamine but not any other amino …

Deciphering The Role Of Rna Structure In Translation Efficiency., Jianan Lin, Yang Chen, Yuping Zhang, Haifan Lin, Zhengqing Ouyang

Faculty Research 2022

BACKGROUND: RNA secondary structure has broad impact on the fate of RNA metabolism. The reduced stability of secondary structures near the translation initiation site/start codon of the coding region promotes the efficiency of translation in both prokaryotic and eukaryotic species. However, the inaccuracy of in silico folding and the focus on the coding region limit our understanding of the global relationship between the whole mRNA structure and translation efficiency. Leveraging high-throughput RNA structure probing data in the transcriptome, we aim to systematically investigate the role of RNA structure in regulating translation efficiency.

RESULTS: Here, we analyze the influences of hundreds …

Trem2 Dependent And Independent Functions Of Microglia In Alzheimer's Disease, Jinchao Hou, Yun Chen, Gary Grajales-Reyes, Marco Colonna

2020-Current year OA Pubs

Microglia are central players in brain innate immunity and have been the subject of extensive research in Alzheimer's disease (AD). In this review, we aim to summarize the genetic and functional discoveries that have advanced our understanding of microglia reactivity to AD pathology. Given the heightened AD risk posed by rare variants of the microglial triggering receptor expressed on myeloid cells 2 (TREM2), we will focus on the studies addressing the impact of this receptor on microglia responses to amyloid plaques, tauopathy and demyelination pathologies in mouse and human. Finally, we will discuss the implications of recent discoveries on microglia …

Proximity-Dependent Biotin Labeling In Testicular Germ Cells Identified Tesmin-Associated Proteins, Seiya Oura, Akinori Ninomiya, Fuminori Sugihara, Martin M Matzuk, Masahito Ikawa

Faculty, Staff and Students Publications

Characterization of protein-protein interactions (PPI) is a key to understanding the functions of proteins of interest. Recently developed proximity-dependent biotin identification (BioID) has been actively investigated as an alternative PPI mapping method because of its usefulness in uncovering transient PPI. Here, as an example of proximity labeling proteomics application in the testis, we generated two transgenic mouse lines expressing two biotin ligases (BioID2 or TurboID) fused with TESMIN, which translocates from the cytosol to the nucleus during meiotic progression and is required for reproduction. The BioID2 transgene, albeit not the TurboID transgene, rescued fertility defects of the Tesmin KO male …

Control Of Sars-Cov-2 Infection By Mt1-Mmp-Mediated Shedding Of Ace2, Xuanming Guo, Jianli Cao, Jian-Piao Cai, Jiayan Wu, Jiangang Huang, Pallavi Asthana, Sheung Kin Ken Wong, Zi-Wei Ye, Susma Gurung, Yijing Zhang, Sheng Wang, Zening Wang, Xin Ge, Hiu Yee Kwan, Aiping Lyu, Kui Ming Chan, Nathalie Wong, Jiandong Huang, Zhongjun Zhou, Zhao-Xiang Bian, Shuofeng Yuan, Hoi Leong Xavier Wong

Faculty, Staff and Student Publications

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic. Angiotensin-converting enzyme 2 (ACE2) is an entry receptor for SARS-CoV-2. The full-length membrane form of ACE2 (memACE2) undergoes ectodomain shedding to generate a shed soluble form (solACE2) that mediates SARS-CoV-2 entry via receptor-mediated endocytosis. Currently, it is not known how the physiological regulation of ACE2 shedding contributes to the etiology of COVID-19 in vivo. The present study identifies Membrane-type 1 Matrix Metalloproteinase (MT1-MMP) as a critical host protease for solACE2-mediated SARS-CoV-2 infection. SARS-CoV-2 infection leads to increased activation of MT1-MMP that is colocalized with ACE2 in human lung …

Hif1a-Dependent Induction Of Alveolar Epithelial Pfkfb3 Dampens Acute Lung Injury, Christine U Vohwinkel, Nana Burns, Ethan Coit, Xiaoyi Yuan, Eszter K Vladar, Christina Sul, Eric P Schmidt, Peter Carmeliet, Kurt Stenmark, Eva S Nozik, Rubin M Tuder, Holger K Eltzschig

Faculty, Staff and Student Publications

Acute lung injury (ALI) is a severe form of lung inflammation causing acute respiratory distress syndrome in patients. ALI pathogenesis is closely linked to uncontrolled alveolar inflammation. We hypothesize that specific enzymes of the glycolytic pathway could function as key regulators of alveolar inflammation. Therefore, we screened isolated alveolar epithelia from mice exposed to ALI induced by injurious ventilation to assess their metabolic responses. These studies pointed us toward a selective role for isoform 3 of the 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB3). Pharmacologic inhibition or genetic deletion of Pfkfb3 in alveolar epithelia (Pfkfb3loxP/loxP SPC-ER-Cre+ mice) was associated with profound increases in ALI during …

Engineering Naturally Occurring Cd7- T Cells For The Immunotherapy Of Hematological Malignancies, Abdullah Freiwan, Jaquelyn T Zoine, Jeremy Chase Crawford, Abishek Vaidya, Stefan A Schattgen, Jacquelyn A Myers, Sagar L Patil, Mahsa Khanlari, Hiroto Inaba, Jeffery M Klco, Charles G Mullighan, Giedre Krenciute, Peter J Chockley, Swati Naik, Deanna M Langfitt, Maksim Mamonkin, Esther A Obeng, Paul G Thomas, Stephen Gottschalk, M Paulina Velasquez

Faculty, Staff and Students Publications

Chimeric antigen receptor (CAR) T-cell therapy targeting T-cell acute lymphoblastic leukemia (T-ALL) faces limitations such as antigen selection and limited T-cell persistence. CD7 is an attractive antigen for targeting T-ALL, but overlapping expression on healthy T cells leads to fratricide of CD7-CAR T cells, requiring additional genetic modification. We took advantage of naturally occurring CD7- T cells to generate CD7-CAR (CD7-CARCD7-) T cells. CD7-CARCD7- T cells exhibited a predominantly CD4+ memory phenotype and had significant antitumor activity upon chronic antigen exposure in vitro and in xenograft mouse models. Based on these encouraging results, we next explored the utility of CD7- …

Impact Of Cd4 T Cells On Intratumoral Cd8 T-Cell Exhaustion And Responsiveness To Pd-1 Blockade Therapy In Mouse Brain Tumors, Saad M. Khan, Rupen Desai, Andrew Coxon, Alexandra Livingstone, Gavin P Dunn, Allegra Petti, Tanner M Johanns

2020-Current year OA Pubs

BACKGROUND: Glioblastoma is a fatal disease despite aggressive multimodal therapy. PD-1 blockade, a therapy that reinvigorates hypofunctional exhausted CD8 T cells (T

METHODS: Single-cell RNA sequencing was performed on flow sorted tumor-infiltrating lymphocytes from female C57/BL6 mice implanted with each model, with and without PD-1 blockade therapy. CD8

RESULTS: The CD8 T-cell compartment of the models is composed of heterogenous CD8 T

CONCLUSIONS: Here, we describe that dysfunctional CD4 T cells are associated with terminal CD8 T-cell exhaustion, suggesting CD4 T cells impact PD-1 blockade efficacy by controlling the severity of exhaustion. Given that CD4 lymphopenia is frequently observed in …

Type Iv Pili Are A Critical Virulence Factor In Clinical Isolates Of Paenibacillus Thiaminolyticus, Christine Hehnly, Petra Erdmann Gilmore, R. Reid Townsend, David D. Limbrick, Et Al.

2020-Current year OA Pubs

Hydrocephalus, the leading indication for childhood neurosurgery worldwide, is particularly prevalent in low- and middle-income countries. Hydrocephalus preceded by an infection, or postinfectious hydrocephalus, accounts for up to 60% of hydrocephalus in these areas. Since many children with hydrocephalus suffer poor long-term outcomes despite surgical intervention, prevention of hydrocephalus remains paramount. Our previous studies implicated a novel bacterial pathogen, Paenibacillus thiaminolyticus, as a causal agent of neonatal sepsis and postinfectious hydrocephalus in Uganda. Here, we report the isolation of three

Ccl4 Regulates Eosinophil Activation In Eosiccl4 Regulates Eosinophil Activation In Eosinophilic Airway Inflammationnophilic Airway Inflammation, Hanh Hong Chu, Yoshiki Kobayashi, Dan Van Bui, Yasutaka Yun, Linh Manh Nguyen, Akitoshi Mitani, Kensuke Suzuki, Mikiya Asako, Akira Kanda, Hiroshi Iwai

Faculty, Staff and Student Publications

Eosinophilic chronic rhinosinusitis (ECRS) is a refractory airway disease accompanied by eosinophilic inflammation, the mechanisms of which are unknown. We recently found that CCL4/MIP-1β-a specific ligand for CCR5 receptors-was implicated in eosinophil recruitment into the inflammatory site and was substantially released from activated eosinophils. Moreover, it was found in nasal polyps from patients with ECRS, primarily in epithelial cells. In the present study, the role of epithelial cell-derived CCL4 in eosinophil activation was investigated. First, CCL4 expression in nasal polyps from patients with ECRS as well as its role of CCL4 in eosinophilic airway inflammation were investigated in an in …

Multiplex Immunofluorescence-Guided Laser Capture Microdissection For Spatial Transcriptomics Of Metastatic Melanoma Tissues., Jan Martinek, Te-Chia Wu, Lili Sun, Jianan Lin, Kyung In Kim, Florentina Marches, Paul Robson, Joshy George, Karolina Palucka

Faculty Research 2022

We describe a pipeline for optimized and streamlined multiplexed immunofluorescence-guided laser capture microdissection allowing the harvest of individual cells based on their phenotype and tissue localization for transcriptomic analysis with next-generation RNA sequencing. Here, we analyze transcriptomes of CD3+ T cells, CD14+ monocytes/macrophages, and melanoma cells in non-dissociated metastatic melanoma tissue. While this protocol is described for melanoma tissues, we successfully applied it to human tonsil, skin, and breast cancer tissues as well as mouse lung tissues. For complete details on the use and execution of this protocol, please refer to Martinek et al. (2022).

In Vivo Characterization Of Glutamine Metabolism Identifies Therapeutic Targets In Clear Cell Renal Cell Carcinoma, Akash K Kaushik, Amy Tarangelo, Lindsey K Boroughs, Mukundan Ragavan, Yuanyuan Zhang, Cheng-Yang Wu, Xiangyi Li, Kristen Ahumada, Jui-Chung Chiang, Vanina T Tcheuyap, Faeze Saatchi, Quyen N Do, Cissy Yong, Tracy Rosales, Christina Stevens, Aparna D Rao, Brandon Faubert, Panayotis Pachnis, Lauren G Zacharias, Hieu Vu, Feng Cai, Thomas P Mathews, Giannicola Genovese, Barbara S Slusher, Payal Kapur, Xiankai Sun, Matthew Merritt, James Brugarolas, Ralph J Deberardinis

Faculty, Staff and Student Publications

Targeting metabolic vulnerabilities has been proposed as a therapeutic strategy in renal cell carcinoma (RCC). Here, we analyzed the metabolism of patient-derived xenografts (tumorgrafts) from diverse subtypes of RCC. Tumorgrafts from VHL-mutant clear cell RCC (ccRCC) retained metabolic features of human ccRCC and engaged in oxidative and reductive glutamine metabolism. Genetic silencing of isocitrate dehydrogenase-1 or isocitrate dehydrogenase-2 impaired reductive labeling of tricarboxylic acid (TCA) cycle intermediates in vivo and suppressed growth of tumors generated from tumorgraft-derived cells. Glutaminase inhibition reduced the contribution of glutamine to the TCA cycle and resulted in modest suppression of tumorgraft growth. Infusions with …

Egfr Is A Master Switch Between Immunosuppressive And Immunoactive Tumor Microenvironment In Inflammatory Breast Cancer, Xiaoping Wang, Takashi Semba, Ganiraju C Manyam, Jing Wang, Shan Shao, Francois Bertucci, Pascal Finetti, Savitri Krishnamurthy, Lan Thi Hanh Phi, Troy Pearson, Steven J Van Laere, Jared K Burks, Evan N Cohen, James M Reuben, Fei Yang, Hu Min, Nicholas Navin, Van Ngu Trinh, Toshiaki Iwase, Harsh Batra, Yichao Shen, Xiang Zhang, Debu Tripathy, Naoto T Ueno

Faculty, Staff and Student Publications

Inflammatory breast cancer (IBC), the most aggressive breast cancer subtype, is driven by an immunosuppressive tumor microenvironment (TME). Current treatments for IBC have limited efficacy. In a clinical trial (NCT01036087), an anti-EGFR antibody combined with neoadjuvant chemotherapy produced the highest pathological complete response rate ever reported in patients with IBC having triple-negative receptor status. We determined the molecular and immunological mechanisms behind this superior clinical outcome. Using novel humanized IBC mouse models, we discovered that EGFR-targeted therapy remodels the IBC TME by increasing cytotoxic T cells and reducing immunosuppressive regulatory T cells and M2 macrophages. These changes were due to …

Evaluation Of Mtorc1 Signaling In Mouse Atherosclerotic Macrophages By Flow Cytometry And Immunofluorescence, Xiangyu Zhang, Jeremiah Stitham, Astrid Rodriguez-Velez, Se-Jin Jeong, Arick Park, Yu-Sheng Yeh, Divya Kapoor, Bettina Mittendorfer, Babak Razani

2020-Current year OA Pubs

Previous studies have demonstrated that a high-protein diet leads to increased atherosclerosis in mice, and that this adverse effect is caused by activation of macrophage mTORC1 signaling. Here, we provide a detailed protocol for the evaluation of diet-induced mTORC1 signaling in plaque macrophages in atherosclerosis-prone apolipoprotein E (ApoE) knockout (KO) mice. This protocol includes flow cytometry and immunofluorescence analysis of atherosclerotic macrophages that can be used to study the atherogenic potential of a variety of mTORC1 modulators. For complete details on the use and execution of this protocol, please refer to Zhang et al. (2020).

Mouse Kidney Nuclear Isolation And Library Preparation For Single-Cell Combinatorial Indexing Rna Sequencing, Haikuo Li, Benjamin D. Humphreys

2020-Current year OA Pubs

Single-cell combinatorial indexing RNA sequencing (sci-RNA-seq3) enables high-throughput single-nucleus transcriptomic profiling of multiple samples in one experiment. Here, we describe an optimized protocol of mouse kidney nuclei isolation and sci-RNA-seq3 library preparation. The use of a dounce tissue homogenizer enables nuclei extraction with high yield. Fixed nuclei are processed for sci-RNA-seq3, and self-loaded transposome Tn5 is used for tagmentation in library generation. The step-by-step protocol allows researchers to generate scalable single-cell transcriptomic data with common laboratory supplies at low cost. For complete details on the use and execution of this protocol, please refer to Li et al. (2022).

Human Nk Cells Confer Protection Against Hiv-1 Infection In Humanized Mice, Can M. Sungur, Qiankun Wang, Ayşe N. Ozantürk, Hongbo Gao, Aaron J. Schmitz, Marina Cella, Wayne M. Yokoyama, Liang Shan

2020-Current year OA Pubs

The role of NK cells against HIV-1 infections remains to be elucidated in vivo. While humanized mouse models potentially could be used to directly evaluate human NK cell responses during HIV-1 infection, improved functional development of human NK cells in these hosts is needed. Here, we report the humanized MISTRG-6-15 mouse model, in which NK cells were quick to expand and exhibit degranulation, cytotoxicity, and proinflammatory cytokine production in nonlymphoid organs upon HIV-1 infection but had reduced functionality in lymphoid organs. Although HIV-1 infection induced functional impairment of NK cells, antiretroviral therapy reinvigorated NK cells in response to HIV-1 rebound …

Tiam1-Mediated Synaptic Plasticity Underlies Comorbid Depression-Like And Ketamine Antidepressant-Like Actions In Chronic Pain, Qin Ru, Yungang Lu, Ali Bin Saifullah, Francisco A Blanco, Changqun Yao, Juan P Cata, De-Pei Li, Kimberley F Tolias, Lingyong Li

Faculty, Staff and Students Publications

Chronic pain often leads to depression, increasing patient suffering and worsening prognosis. While hyperactivity of the anterior cingulate cortex (ACC) appears to be critically involved, the molecular mechanisms underlying comorbid depressive symptoms in chronic pain remain elusive. T cell lymphoma invasion and metastasis 1 (Tiam1) is a Rac1 guanine nucleotide exchange factor (GEF) that promotes dendrite, spine, and synapse development during brain development. Here, we show that Tiam1 orchestrates synaptic structural and functional plasticity in ACC neurons via actin cytoskeleton reorganization and synaptic N-methyl-d-aspartate receptor (NMDAR) stabilization. This Tiam1-coordinated synaptic plasticity underpins ACC hyperactivity and drives chronic pain-induced depressive-like behaviors. …

Gata1 Controls Numbers Of Hematopoietic Progenitors And Their Response To Autoimmune Neuroinflammation, Daniel Hwang, Larissa Ishikawa, Maryam S. Seyedsadr, Elisabeth R. Mari, Ezgi Kasimoglu, Ziver Sahin, Alexandra Boehm, Soohwa Jang, Javad Rasouli, Courtney Vaccaro, Michael Gonzalez, Hakon Hakonarson, Mohamad Rostami, Guang-Xian Zhang, Bogoljub Ciric

Department of Neurology Faculty Papers

GATA-binding factor 1 (GATA1) is a transcription factor that governs the development and function of multiple hematopoietic cell lineages. GATA1 is expressed in hematopoietic stem and progenitor cells (HSPCs) and is essential for erythroid lineage commitment; however, whether it plays a role in hematopoietic stem cell (HSC) biology and the development of myeloid cells, and what that role might be, remains unclear. We initially set out to test the role of eosinophils in experimental autoimmune encephalomyelitis (EAE), a model of central nervous system autoimmunity, using mice lacking a double GATA-site (ΔdblGATA), which lacks eosinophils due to the deletion of the …

Defining Cellular Population Dynamics At Single-Cell Resolution During Prostate Cancer Progression, Alexandre A Germanos, Sonali Arora, Ye Zheng, Erica T Goddard, Ilsa M Coleman, Anson T Ku, Scott Wilkinson, Hanbing Song, Nicholas J Brady, Robert A Amezquita, Michael Zager, Annalysa Long, Yu Chi Yang, Jason H Bielas, Raphael Gottardo, David S Rickman, Franklin W Huang, Cyrus M Ghajar, Peter S Nelson, Adam G Sowalsky, Manu Setty, Andrew C Hsieh

Faculty, Staff and Student Publications

Advanced prostate malignancies are a leading cause of cancer-related deaths in men, in large part due to our incomplete understanding of cellular drivers of disease progression. We investigate prostate cancer cell dynamics at single-cell resolution from disease onset to the development of androgen independence in an in vivo murine model. We observe an expansion of a castration-resistant intermediate luminal cell type that correlates with treatment resistance and poor prognosis in human patients. Moreover, transformed epithelial cells and associated fibroblasts create a microenvironment conducive to pro-tumorigenic immune infiltration, which is partially androgen responsive. Androgen-independent prostate cancer leads to significant diversification of …

Neuronal Signal-Regulatory Protein Alpha Drives Microglial Phagocytosis By Limiting Microglial Interaction With Cd47 In The Retina, Danye Jiang, Courtney A Burger, Viktor Akhanov, Justine H Liang, Robert D Mackin, Nicholas E Albrecht, Pilar Andrade, Dorothy P Schafer, Melanie A Samuel

Center on Aging Staff Publications

Microglia utilize their phagocytic activity to prune redundant synapses and refine neural circuits during precise developmental periods. However, the neuronal signals that control this phagocytic clockwork remain largely undefined. Here, we show that neuronal signal-regulatory protein alpha (SIRPα) is a permissive cue for microglial phagocytosis in the developing murine retina. Removal of neuronal, but not microglial, SIRPα reduced microglial phagocytosis, increased synpase numbers, and impaired circuit function. Conversely, prolonging neuronal SIRPα expression extended developmental microglial phagocytosis. These outcomes depended on the interaction of presynaptic SIRPα with postsynaptic CD47. Global CD47 deficiency modestly increased microglial phagocytosis, while CD47 overexpression reduced it. …

Stat3 Gain-Of-Function Mutations Connect Leukemia With Autoimmune Disease By Pathological Nkg2dhi Cd8+ T Cell Dysregulation And Accumulation, Etienne Masle-Farquhar, Megan A Cooper, Tiphanie P Vogel, Et Al.

2020-Current year OA Pubs

The association between cancer and autoimmune disease is unexplained, exemplified by T cell large granular lymphocytic leukemia (T-LGL) where gain-of-function (GOF) somatic STAT3 mutations correlate with co-existing autoimmunity. To investigate whether these mutations are the cause or consequence of CD8

Tenotomy-Induced Muscle Atrophy Is Sex-Specific And Independent Of Nfκb, Gretchen A Meyer, Stavros Thomopoulos, Yousef Abu-Amer, Karen C Shen

2020-Current year OA Pubs

The nuclear factor-κB (NFκB) pathway is a major thoroughfare for skeletal muscle atrophy and is driven by diverse stimuli. Targeted inhibition of NFκB through its canonical mediator IKKβ effectively mitigates loss of muscle mass across many conditions, from denervation to unloading to cancer. In this study, we used gain- and loss-of-function mouse models to examine the role of NFκB in muscle atrophy following rotator cuff tenotomy - a model of chronic rotator cuff tear. IKKβ was knocked down or constitutively activated in muscle-specific inducible transgenic mice to elicit a twofold gain or loss of NFκB signaling. Surprisingly, neither knockdown of …

Loss Of Pex1 In Inner Ear Hair Cells Contributes To Cochlear Synaptopathy And Hearing Loss., Stephanie A Mauriac, Thibault Peineau, Aamir Zuberi, Cathleen Lutz, Gwénaëlle S G Géléoc

Faculty Research 2022

Peroxisome Biogenesis Disorders (PBD) and Zellweger syndrome spectrum disorders (ZSD) are rare genetic multisystem disorders that include hearing impairment and are associated with defects in peroxisome assembly, function, or both. Mutations in 13 peroxin (PEX) genes have been found to cause PBD-ZSD with ~70% of patients harboring mutations in PEX1. Limited research has focused on the impact of peroxisomal disorders on auditory function. As sensory hair cells are particularly vulnerable to metabolic changes, we hypothesize that mutations in PEX1 lead to oxidative stress affecting hair cells of the inner ear, subsequently resulting in hair cell degeneration and hearing loss. Global …

An Elf4 Hypomorphic Variant Results In Nk Cell Deficiency, Sandra Andrea Salinas, Emily M Mace, Matilde I Conte, Chun Shik Park, Yu Li, Joshua I Rosario-Sepulveda, Sanjana Mahapatra, Emily K Moore, Evelyn R Hernandez, Ivan K Chinn, Abigail E Reed, Barclay J Lee, Alexander Frumovitz, Richard A Gibbs, Jennifer E Posey, Lisa R Forbes Satter, Akaluck Thatayatikom, Eric J Allenspach, Theodore G Wensel, James R Lupski, H Daniel Lacorazza, Jordan S Orange

Faculty, Staff and Students Publications

NK cell deficiencies (NKD) are a type of primary immune deficiency in which the major immunologic abnormality affects NK cell number, maturity, or function. Since NK cells contribute to immune defense against virally infected cells, patients with NKD experience higher susceptibility to chronic, recurrent, and fatal viral infections. An individual with recurrent viral infections and mild hypogammaglobulinemia was identified to have an X-linked damaging variant in the transcription factor gene ELF4. The variant does not decrease expression but disrupts ELF4 protein interactions and DNA binding, reducing transcriptional activation of target genes and selectively impairing ELF4 function. Corroborating previous murine models …

Targeting Tmem205 Mediated Drug Resistance In Ovarian Clear Cell Carcinoma Using Oncolytic Virus, Uksha Saini, Brentley Q Smith, Kalpana Deepa Priya Dorayappan, Ji Young Yoo, G Larry Maxwell, Balveen Kaur, Ikuo Konishi, David O'Malley, David E Cohn, Karuppaiyah Selvendiran

Faculty, Staff and Student Publications

BACKGROUND: Ovarian clear cell carcinoma (OCCC) accounts for approximately 8-10% of epithelial ovarian cancers in the United States. Although it is rare, OCCC usually presents with treatment challenges and the overall prognosis is far worse than high grade serous ovarian cancer HGSOC. The objective of this study was to examine the therapeutic relevance of combining oncolytic virus with cisplatin for ovarian cancer clear cell carcinoma (OCCC).

RESULTS: We identified that TMEM205, a recently discovered transmembrane protein, contributes to chemoresistance in OCCC cells via the exosomal pathway. Mechanistically, TMEM205 undergoes ligand-independent constitutive endocytosis and co-localizes with Rab11 to contribute to the …

Identification Of Acenkps, A Committed Common Progenitor Population Of The Ilc1 And Nk Cell Continuum, Noe Rodriguez-Rodriguez, Paula A Clark, Mayuri Gogoi, Ana C F Ferreira, Bernhard Kerscher, Alastair Crisp, Helen E Jolin, Jane E Murphy, Meera Sivasubramaniam, Luisa Pedro, Jennifer A Walker, Morgan W D Heycock, Jacqueline D Shields, Jillian L Barlow, Andrew N J Mckenzie

Faculty, Staff and Student Publications

The development of innate lymphoid cell (ILC) transcription factor reporter mice has shown a previously unexpected complexity in ILC hematopoiesis. Using novel polychromic mice to achieve higher phenotypic resolution, we have characterized bone marrow progenitors that are committed to the group 1 ILC lineage. These common ILC1/NK cell progenitors (ILC1/NKP), which we call "aceNKPs", are defined as lineage-Id2+IL-7Rα+CD25-α4β7-NKG2A/C/E+Bcl11b-. In vitro, aceNKPs differentiate into group 1 ILCs, including NK-like cells that express Eomes without the requirement for IL-15, and produce IFN-γ and perforin upon IL-15 stimulation. Following reconstitution of Rag2-/-Il2rg-/- hosts, aceNKPs give rise to a spectrum of mature ILC1/NK cells …