Medicine and Health Sciences Commons^™

Granulocytic Myeloid-Derived Suppressor Cell Activity During Biofilm Infection Is Regulated By A Glycolysis/Hif1a Axis, Christopher M. Horn, Prabhakar Arumugam, Zachary Van Roy, Cortney E. Heim, Rachel W. Fallet, Blake P. Bertrand, Dhananjay Shinde, Vinai Chittezham Thomas, Svetlana Romanova, Tatiana K. Bronich, Curtis Hartman, Kevin Garvin, Tammy Kielian

Journal Articles: Pathology and Microbiology

Staphylococcus aureus is a leading cause of biofilm-associated prosthetic joint infection (PJI). A primary contributor to infection chronicity is an expansion of granulocytic myeloid-derived suppressor cells (G-MDSCs), which are critical for orchestrating the antiinflammatory biofilm milieu. Single-cell sequencing and bioinformatic metabolic algorithms were used to explore the link between G-MDSC metabolism and S. aureus PJI outcome. Glycolysis and the hypoxia response through HIF1a were significantly enriched in G-MDSCs. Interfering with both pathways in vivo, using a 2-deoxyglucose nanopreparation and granulocyte-targeted Hif1a conditional KO mice, respectively, attenuated G-MDSC-mediated immunosuppression and reduced bacterial burden in a mouse model of S. aureus PJI. …

Investigation Into Cardiac Myhc-Α 334-352-Specific Tcr Transgenic Mice Reveals A Role For Cytotoxic Cd4 T Cells In The Development Of Cardiac Autoimmunity, Meghna Sur, Mahima T. Rasquinha, Kiruthiga Mone, Chandirasegaran Massilamany, Ninaad Lasrado, Channabasavaiah B. Gurumurthy, Raymond A Sobel, Jay Reddy

Journal Articles: Genetics, Cell Biology & Anatomy

Myocarditis is one of the major causes of heart failure in children and young adults and can lead to dilated cardiomyopathy. Lymphocytic myocarditis could result from autoreactive CD4⁺ and CD8⁺ T cells, but defining antigen specificity in disease pathogenesis is challenging. To address this issue, we generated T cell receptor (TCR) transgenic (Tg) C57BL/6J mice specific to cardiac myosin heavy chain (Myhc)-α 334-352 and found that Myhc-α-specific TCRs were expressed in both CD4⁺ and CD8⁺ T cells. To investigate if the phenotype is more pronounced in a myocarditis-susceptible genetic background, we backcrossed with A/J mice. At …

Targeting Transitioning Lung Monocytes/Macrophages As Treatment Strategies In Lung Disease Related To Environmental Exposures, Aaron Schwab, Todd A. Wyatt, Grace Moravec, Geoffrey M. Thiele, Amy J. Nelson, Angela Gleason, Oliver Schanze, Michael J. Duryee, Debra J. Romberger, Ted R. Mikuls, Jill A. Poole

Journal Articles: Pulmonary & Critical Care Med

Background: Environmental/occupational exposures cause significant lung diseases. Agricultural organic dust extracts (ODE) and bacterial component lipopolysaccharide (LPS) induce recruited,transitioning murine lung monocytes/macrophages, yet their cellular role remains unclear.

Methods: CCR2 RFP⁺ mice were intratracheally instilled with high concentration ODE (25%), LPS (10 μg), or gram-positive peptidoglycan (PGN, 100 μg) for monocyte/macrophage cell-trafficking studies. CCR2 knockout (KO) mice and administration of intravenous clodronate liposomes strategies were employed to reduce circulating monocytes available for lung recruitment following LPS exposure.Lung tissues and bronchoalveolar lavage fluid (BALF) were collected. Pro-inflammatory and/or pro-fibrotic cytokines, chemokines, and lung extracellular matrix mediators were quantitated by ELISA. …

Lung-Delivered Il-10 Therapy Elicits Beneficial Effects Via Immune Modulation In Organic Dust Exposure-Induced Lung Inflammation, Aaron D. Schwab, Todd A. Wyatt, Amy J. Nelson, Angela Gleason, Rohit Gaurav, Debra J. Romberger, Jill A. Poole

Journal Articles: Pulmonary & Critical Care Med

Efficacious therapeutic options capable of resolving inflammatory lung disease associated with environmental and occupational exposures are lacking. This study sought to determine the preclinical therapeutic potential of lung-delivered recombinant interleukin (IL)-10 therapy following acute organic dust exposure in mice. Here, C57BL/6J mice were intratracheally instilled with swine confinement organic dust extract (ODE) (12.5%, 25%, 50% concentrations) with IL-10 (1 μg) treatment or vehicle control intratracheally-administered three times: 5 hr post-exposure and then daily for 2 days. The results showed that IL-10 treatment reduced ODE (25%)-induced weight loss by 66% and 46% at Day 1 and Day 2 post-exposure, respectively. IL-10 …

Novel Spirocyclic Dimer, Spid3, Targets Chronic Lymphocytic Leukemia Survival Pathways With Potent Preclinical Effects, Alexandria Eiken, Audrey L. Smith, Sydney A. Skupa, Elizabeth Schmitz, Sandeep Rana, Sarbjit Singh, Siddhartha Kumar, Jayapal Reddy Mallareddy, Aguirre A. De Cubas, Akshay Krishna, Achyuth Kalluchi, M. Jordan Rowley, Christopher R. D'Angelo, Matthew A. Lunning, Gregory Bociek, Julie M. Vose, Amarnath Natarajan, Dalia El-Gamal

Journal Articles: Oncology and Hematology

Chronic lymphocytic leukemia (CLL) cell survival and growth is fueled by the induction of B-cell receptor (BCR) signaling within the tumor microenvironment (TME) driving activation of NFκB signaling and the unfolded protein response (UPR). Malignant cells have higher basal levels of UPR posing a unique therapeutic window to combat CLL cell growth using pharmacologic agents that induce accumulation of misfolded proteins. Frontline CLL therapeutics that directly target BCR signaling such as Bruton tyrosine kinase (BTK) inhibitors (e.g., ibrutinib) have enhanced patient survival. However, resistance mechanisms wherein tumor cells bypass BTK inhibition through acquired BTK mutations, and/or activation of alternative survival …

Bet Inhibition Reforms The Immune Microenvironment And Alleviates T Cell Dysfunction In Chronic Lymphocytic Leukemia, Audrey L. Smith, Sydney A. Skupa, Alexandria P. Eiken, Timothy E. Reznicek, Elizabeth Schmitz, Nolan Williams, Dalia Y. Moore, Christopher R. D'Angelo, Avyakta Kallam, Matthew A. Lunning, Gregory Bociek, Julie M. Vose, Eslam Mohamed, Anna R. Mahr, Paul W. Denton, Ben Powell, Gideon Bollag, M. Jordan Rowley, Dalia El-Gamal

Journal Articles: Oncology and Hematology

Redundant tumor microenvironment (TME) immunosuppressive mechanisms and epigenetic maintenance of terminal T cell exhaustion greatly hinder functional antitumor immune responses in chronic lymphocytic leukemia (CLL). Bromodomain and extraterminal (BET) proteins regulate key pathways contributing to CLL pathogenesis and TME interactions, including T cell function and differentiation. Herein, we report that blocking BET protein function alleviates immunosuppressive networks in the CLL TME and repairs inherent CLL T cell defects. The pan-BET inhibitor OPN-51107 reduced exhaustion-associated cell signatures resulting in improved T cell proliferation and effector function in the Eμ-TCL1 splenic TME. Following BET inhibition (BET-i), TME T cells coexpressed significantly fewer …

Targeted Insertion Of Conditional Expression Cassettes Into The Mouse Genome Using The Modified I-Pitt, Hiromi Miura, Ayaka Nakamura, Aki Kurosaki, Ai Kotani, Masaru Motojima, Keiko Tanaka, Shigeru Kakuta, Sanae Ogiwara, Yuhsuke Ohmi, Hirotaka Komaba, Samantha L. P. Schilit, Cynthia C. Morton, Channabasavaiah B. Gurumurthy, Masato Ohtsuka

Journal Articles: Genetics, Cell Biology & Anatomy

BACKGROUND: Transgenic (Tg) mice are widely used in biomedical research, and they are typically generated by injecting transgenic DNA cassettes into pronuclei of one-cell stage zygotes. Such animals often show unreliable expression of the transgenic DNA, one of the major reasons for which is random insertion of the transgenes. We previously developed a method called "pronuclear injection-based targeted transgenesis" (PITT), in which DNA constructs are directed to insert at pre-designated genomic loci. PITT was achieved by pre-installing so called landing pad sequences (such as heterotypic LoxP sites or attP sites) to create seed mice and then injecting Cre recombinase or …