Medical Cell Biology Commons^™

Toll-Like Receptor 4 Signaling In Osteoblasts Is Required For Load-Induced Bone Formation In Mice, Ibtesam Rajpar, Gaurav Kumar, Paolo Fortina, Ryan E. Tomlinson

Department of Orthopaedic Surgery Faculty Papers

In mature bone, NGF is produced by osteoblasts following mechanical loading and signals through resident sensory nerves expressing its high affinity receptor, neurotrophic tyrosine kinase receptor type 1 (TrkA), to support bone formation. Here, we investigated whether osteoblastic expression of Toll-like receptor 4 (TLR4), a key receptor in the NF-κB signaling pathway, is required to initiate NGF-TrkA signaling required for load-induced bone formation. Although Tlr4 conditional knockout mice have normal skeletal mass and strength in adulthood, the loss of TLR4 signaling significantly reduced lamellar bone formation following loading. Inhibition of TLR4 signaling reduced Ngf expression in primary osteoblasts and RNA …

Role Of Ribosome Recycling Factor In Natural Termination And Translational Coupling As A Ribosome Releasing Factor, Yoshio Inokuchi, Fabio Quaglia, Akikazu Hirashima, Yoshihiro Yamamoto, Hideko Kaji, Akira Kaji

Department of Biochemistry and Molecular Biology Faculty Papers

The role of ribosome recycling factor (RRF) of E. coli was studied in vivo and in vitro. We used the translational coupling without the Shine-Dalgarno sequence of downstream ORF (d-ORF) as a model system of the RRF action in natural termination of protein synthesis. For the in vivo studies we used the translational coupling by the adjacent coat and lysis genes of RNA phage GA sharing the termination and initiation (UAAUG) and temperature sensitive RRF. The d-ORF translation was measured by the expression of the reporter lacZ gene connected to the 5'-terminal part of the lysis gene. The results showed …

Emerging Treatments For Myelodysplastic Syndromes: Biological Rationales And Clinical Translation, Juan Jose Rodriguez-Sevilla, Vera Adema, Guillermo Garcia-Manero, Simona Colla

Faculty, Staff and Student Publications

Myelodysplastic syndromes (MDSs) are a heterogeneous group of clonal hematopoietic stem cell disorders characterized by myeloid dysplasia, peripheral blood cytopenias, and increased risk of progression to acute myeloid leukemia (AML). The standard of care for patients with MDS is hypomethylating agent (HMA)-based therapy; however, nearly 50% of patients have no response to the treatment. Patients with MDS in whom HMA therapy has failed have a dismal prognosis and no approved second-line therapy options, so enrollment in clinical trials of experimental agents represents these patients' only chance for improved outcomes. A better understanding of the molecular and biological mechanisms underpinning MDS …

Differential Regulation Of H3k9/H3k14 Acetylation By Small Molecules Drives Neuron-Fate-Induction Of Glioma Cell, Xincheng Liu, Cui Guo, Tiandong Leng, Zhen Fan, Jialuo Mai, Jiehong Chen, Jinhai Xu, Qianyi Li, Bin Jiang, Ke Sai, Wenzhuo Yang, Jiayu Gu, Jingyi Wang, Shuxin Sun, Zhijie Chen, Yingqian Zhong, Xuanming Liang, Chaoxin Chen, Jing Cai, Yuan Lin, Jiankai Liang, Jun Hu, Guangmei Yan, Wenbo Zhu, Wei Yin

Faculty, Staff and Student Publications

Differentiation therapy using small molecules is a promising strategy for improving the prognosis of glioblastoma (GBM). Histone acetylation plays an important role in cell fate determination. Nevertheless, whether histone acetylation in specific sites determines GBM cells fate remains to be explored. Through screening from a 349 small molecule-library, we identified that histone deacetylase inhibitor (HDACi) MS-275 synergized with 8-CPT-cAMP was able to transdifferentiate U87MG GBM cells into neuron-like cells, which were characterized by cell cycle arrest, rich neuron biomarkers, and typical neuron electrophysiology. Intriguingly, acetylation tags of histone 3 at lysine 9 (H3K9ac) were decreased in the promoter of multiple …

Endothelial-To-Osteoblast Transition In Normal Mouse Bone Development, Song-Chang Lin, Guoyu Yu, Yu-Chen Lee, Jian H Song, Xingzhi Song, Jianhua Zhang, Theocharis Panaretakis, Christopher J Logothetis, Yoshihiro Komatsu, Li-Yuan Yu-Lee, Guocan Wang, Sue-Hwa Lin

Faculty, Staff and Student Publications

Metastatic prostate cancer (PCa) in bone induces bone-forming lesions. We have previously shown that PCa-induced bone originates from endothelial cells (ECs) that have undergone EC-to-osteoblast (OSB) transition. Here, we investigated whether EC-to-OSB transition also occurs during normal bone formation. We developed an EC and OSB dual-color reporter mouse (DRM) model that marks EC-OSB hybrid cells with red and green fluorescent proteins. We observed EC-to-OSB transition (RFP and GFP co-expression) in both endochondral and intramembranous bone formation during embryonic development and in adults. Co-expression was confirmed in cells isolated from DRM. Bone marrow– and lung-derived ECs underwent transition to OSBs and …

Estimated Impact Of Low Isolate Numbers On The Reliability Of Cumulative Antibiogram Data, Christian Tran, John Hargy, Bryan Hess, Matthew Pettengill

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Antibiograms are cumulative reports of antimicrobial susceptibility results that are used to guide the selection of empirical antibiotic therapy. Although Clinical and Laboratory Standards Institute (CLSI) guidelines recommend including only organisms that have at least 30 isolates in an antibiogram, previous studies demonstrated that adherence to this recommendation is highly variable. This paper aims to model the impact of small sample sizes on expected levels of error in cumulative antibiograms by comparing percent susceptibility results for random samples to those of the larger, entire data set. The results demonstrate relatively high error rates when utilizing low numbers of isolates in …

Massive Loss Of Proprioceptive Ia Synapses In Rat Spinal Motoneurons After Nerve Crush Injuries In The Postnatal Period, Ariadna Arbat-Plana, Sara Bolívar, Xavier Navarro, Esther Udina, Francisco J. Alvarez

Neuroscience, Cell Biology & Physiology Faculty Publications

Peripheral nerve injuries (PNIs) induce the retraction from the ventral horn of the synaptic collaterals of Ia afferents injured in the nerve, effectively removing Ia synapses from α-motoneurons. The loss of Ia input impairs functional recovery and could explain, in part, better recovery after PNIs with better Ia synaptic preservation. Synaptic losses correlate with injury severity, speed, and efficiency of muscle reinnervation and requires ventral microglia activation. It is unknown whether this plasticity is age dependent. In neonates, axotomized motoneurons and sensory neurons undergo apoptosis, but after postnatal day 10 most survive. The goal of this study was to analyze …

Development Of A Novel Mathematical Model That Explains Sars-Cov-2 Infection Dynamics In Caco-2 Cells, Vladimir Staroverov, Stepan Nersisyan, Alexei Galatenko, Dmitriy Alekseev, Sofya Lukashevich, Fedor Ployakov, Nikita Anisimov, Alexander Tonevitsky

COVID-19 Papers, Posters, and Presentations

Mathematical modeling is widely used to study within-host viral dynamics. However, to the best of our knowledge, for the case of SARS-CoV-2 such analyses were mainly conducted with the use of viral load data and for the wild type (WT) variant of the virus. In addition, only few studies analyzed models for in vitro data, which are less noisy and more reproducible. In this work we collected multiple data types for SARS-CoV-2-infected Caco-2 cell lines, including infectious virus titers, measurements of intracellular viral RNA, cell viability data and percentage of infected cells for the WT and Delta variants. We showed …

Tissue-Resident Memory T Cells Trigger Rapid Exudation And Local Antibody Accumulation, Pamela C Rosato, Sahar Lotfi-Emran, Vineet Joag, Sathi Wijeyesinghe, Clare F Quarnstrom, Hanna N Degefu, Rebecca Nedellec, Jason M Schenkel, Lalit K Beura, Lars Hangartner, Dennis R Burton, David Masopust

Faculty, Staff and Student Publications

Adaptive immunity is didactically partitioned into humoral and cell-mediated effector mechanisms, which may imply that each arm is separate and does not function together. Here, we report that the activation of CD8+ resident memory T cells (TRM) in nonlymphoid tissues triggers vascular permeability, which facilitates rapid distribution of serum antibodies into local tissues. TRM reactivation was associated with transcriptional upregulation of antiviral signaling pathways as well as Fc receptors and components of the complement cascade. Effects were local, but evidence is presented that TRM in brain and reproductive mucosa are both competent to induce rapid antibody exudation. TRM reactivation in …

Fibrinogen-Like Protein 2: Its Biological Function Across Cell Types And The Potential To Serve As An Immunotherapy Target For Brain Tumors, Sheng Zhang, Ganesh Rao, Amy Heimberger, Shulin Li

Faculty, Staff and Student Publications

Brain tumors are among the 10 leading causes of cancer-related death and present unique treatment challenges due to their critical location, genetic heterogeneity, and the blood-brain barrier. Recent advances in targeted immunotherapy and immune checkpoint blocking therapy provide alternative therapeutic strategies for brain tumors. Fibrinogen-like protein 2 (FGL2), which induces transformation from low-grade glioma to high-grade glioblastoma, is a type II membrane protein that is highly expressed in both host immune cells and tumor cells. Studies have uncovered multiple forms of FGL2 proteins with a broad range of roles in inducing immune tolerance and avoiding immune surveillance in tumor cells. …

Mixcan: A Framework For Cell-Type-Aware Transcriptome-Wide Association Studies With An Application To Breast Cancer, Xiaoyu Song, Jiayi Ji, Joseph H Rothstein, Stacey E Alexeeff, Lori C Sakoda, Adriana Sistig, Ninah Achacoso, Eric Jorgenson, Alice S Whittemore, Robert J Klein, Laurel A Habel, Pei Wang, Weiva Sieh

Faculty, Staff and Student Publications

Human bulk tissue samples comprise multiple cell types with diverse roles in disease etiology. Conventional transcriptome-wide association study approaches predict genetically regulated gene expression at the tissue level, without considering cell-type heterogeneity, and test associations of predicted tissue-level expression with disease. Here we develop MiXcan, a cell-type-aware transcriptome-wide association study approach that predicts cell-type-level expression, identifies disease-associated genes via combination of cell-type-level association signals for multiple cell types, and provides insight into the disease-critical cell type. As a proof of concept, we conducted cell-type-aware analyses of breast cancer in 58,648 women and identified 12 transcriptome-wide significant genes using MiXcan compared …

Fast Blue And Cholera Toxin-B Survival Guide For Alpha-Motoneurons Labeling: Less Is Better In Young B6sjl Mice, But More Is Better In Aged C57bl/J Mice, Hasan Farid, Weston B. Gleford, Lori L. Goss, Teresa L. Garrett, Sherif M. Elbasiouny

Neuroscience, Cell Biology & Physiology Faculty Publications

Fast Blue (FB) and Cholera Toxin-B (CTB) are two retrograde tracers extensively used to label alpha-motoneurons (α-MNs). The overall goals of the present study were to (1) assess the effectiveness of different FB and CTB protocols in labeling α-MNs, (2) compare the labeling quality of these tracers at standard concentrations reported in the literature (FB 2% and CTB 0.1%) versus lower concentrations to overcome tracer leakage, and (3) determine an optimal protocol for labeling α-MNs in young B6SJL and aged C57Bl/J mice (when axonal transport is disrupted by aging). Hindlimb muscles of young B6SJL and aged C57Bl/J mice were intramuscularly …

Hypoxia Truncates And Constitutively Activates The Key Cholesterol Synthesis Enzyme Squalene Monooxygenase, Hudson W Coates, Isabelle M Capell-Hattam, Ellen M Olzomer, Ximing Du, Rhonda Farrell, Hongyuan Yang, Frances L Byrne, Andrew J Brown

Faculty, Staff and Student Publications

Cholesterol synthesis is both energy- and oxygen-intensive, yet relatively little is known of the regulatory effects of hypoxia on pathway enzymes. We previously showed that the rate-limiting and first oxygen-dependent enzyme of the committed cholesterol synthesis pathway, squalene monooxygenase (SM), can undergo partial proteasomal degradation that renders it constitutively active. Here, we show hypoxia is a physiological trigger for this truncation, which occurs through a two-part mechanism: (1) increased targeting of SM to the proteasome via stabilization of the E3 ubiquitin ligase MARCHF6 and (2) accumulation of the SM substrate, squalene, which impedes the complete degradation of SM and liberates …

Editorial: Hallmark Of Cancer: Reprogramming Of Cellular Metabolism, Baljinder Kaur, Yahya Sohrabi, Abhinav Achreja, Michael P. Lisanti, Ubaldo Emilio Martinez-Outshoorn

Department of Medical Oncology Faculty Papers

No abstract provided.

Molecular Subtyping And Survival Analysis Of Osteosarcoma Reveals Prognostic Biomarkers And Key Canonical Pathways, Siddesh Southekal, Sushil Kumar Shakyawar, Prachi Bajpai, Amr Elkholy, Upender Manne, Nitish Kumar Mishra, Chittibabu Guda

Journal Articles: Genetics, Cell Biology & Anatomy

Osteosarcoma (OS) is a common bone malignancy in children and adolescents. Although histological subtyping followed by improved OS treatment regimens have helped achieve favorable outcomes, a lack of understanding of the molecular subtypes remains a challenge to characterize its genetic heterogeneity and subsequently to identify diagnostic and prognostic biomarkers for developing effective treatments. In the present study, global analysis of DNA methylation, and mRNA and miRNA gene expression in OS patient samples were correlated with their clinical characteristics. The mucin family of genes, MUC6, MUC12, and MUC4, were found to be highly mutated in the OS patients. …

Proposing An Rna Interference (Rnai)-Based Treatment For Human Immunodeficiency Virus (Hiv) By Analyzing The Post-Transcriptional Gene Targeting Of Sars-Cov-2, Hepatitis C Virus, And A549 Lung Cancer Cells, Arjun Jagdeesh

UROP Posters

Human Immunodeficiency Virus (HIV) is a retrovirus that infects CD4+ T cell lymphocytes in humans, leading to the development of Acquired Immunodeficiency Syndrome (AIDS) if left untreated. While current treatment methods, including antiretroviral combination treatments, effectively limit HIV replication, HIV can evade these treatments due to its high mutation rate. Long-term antiretroviral treatment can also be toxic to patients, meaning patients would benefit from a new mechanism of HIV treatment. RNA interference (RNAi) is an antiviral pathway found in mammals, plants, and insects that involves a small-interfering RNA that is incorporated into a protein complex called the RNA-induced Silencing Complex …

Investigation Of The Dyrk1a Regulation By Lzts2-Sipa1l1 Complex, Rebecca Gunnin, Austin Witt B.S., Larisa Litovchick M.D.,Ph.D.

UROP Posters

A region on chromosome 21, the Down Syndrome critical region (DSCR), is associated with major defects found in Down Syndrome, such as craniofacial malformations. DYRK1A is a gene found on chromosome 21 within the DSCR that encodes an enzyme, dual specificity tyrosine-phosphorylation-regulated kinase 1A. DYRK1A is known to phosphorylate many substrate proteins and is thought to be involved in tumor suppression, neurological development, cell cycle regulation, and aging. Recently, the Litovchick lab and others reported that DYRK1A also plays a role in the double-strand break repair of DNA, which could lead to mutations and tumorigenesis, if deregulated.

The Litovchick lab …

Isoprenylation Inhibition Suppresses Fcεri-Mediated Mast Cell Function And Allergic Inflammation, Aditya Kotha, Jordan M. Dailey, Aslamuzzaman Kazi, Said Sebti, John J. Ryan

UROP Posters

Allergic disease is driven by cell signaling cascades that activate immune cells. One key player is mast cells, which is activated by IgE antibodies signaling through the high affinity IgE receptor, FceRI. Therefore, targeting FceRI-mediated cascades can offer for novel treatments for allergic disease. Statins have been demonstrated to reduce the severity of asthma, a common allergic airway disease. Statins are an FDA approved class of drugs with the intended purpose of lowering blood cholesterol. We previously found that while statins inhibit mast cell function in allergic disease, these anti-inflammatory effects vary widely amongst differing mouse strains and human donors, …

A Facile Strategy For The Fabrication Of Cell-Laden Porous Alginate Hydrogels Based On Two-Phase Aqueous Emulsions, Wen Xue, Donghee Lee, Yunfan Kong, Mitchell A. Kuss, Ying Huang, Taesung Kim, Soonkyu Chung, Andrew T. Dudley, Seung-Hyun Ro, Bin Duan

Journal Articles: Genetics, Cell Biology & Anatomy

Porous alginate (Alg) hydrogels possess many advantages as cell carriers. However, current pore generation methods require either complex or harsh fabrication processes, toxic components, or extra purification steps, limiting the feasibility and affecting the cellular survival and function. In this study, a simple and cell-friendly approach to generate highly porous cell-laden Alg hydrogels based on two-phase aqueous emulsions is reported. The pre-gel solutions, which contain two immiscible aqueous phases of Alg and caseinate (Cas), are cross-linked by calcium ions. The porous structure of the hydrogel construct is formed by subsequently removing the Cas phase from the ion-cross-linked Alg hydrogel. Those …

Rescue Of Auditory Function By A Single Administration Of Aav-Tmprss3 Gene Therapy In Aged Mice Of Human Recessive Deafness Dfnb8, Wan Du, Volkan Ergin, Corena Loeb, Mingqian Huang, Stewart Silver, Ariel Miura Armstrong, Zaohua Huang, Channabasavaiah B. Gurumurthy, Hinrich Staecker, Xuezhong Liu, Zheng-Yi Chen

Journal Articles: Genetics, Cell Biology & Anatomy

Patients with mutations in the TMPRSS3 gene suffer from recessive deafness DFNB8/DFNB10. For these patients, cochlear implantation is the only treatment option. Poor cochlear implantation outcomes are seen in some patients. To develop biological treatment for TMPRSS3 patients, we generated a knockin mouse model with a frequent human DFNB8 TMPRSS3 mutation. The Tmprss3^A306T/A306T homozygous mice display delayed onset progressive hearing loss similar to human DFNB8 patients. Using AAV2 as a vector to carry a human TMPRSS3 gene, AAV2-hTMPRSS3 injection in the adult knockin mouse inner ear results in TMPRSS3 expression in the hair cells and the spiral ganglion neurons. …