bluuebunny/crossref_metadata_2025_split huggingface dataset:
Complement-dependent phagocytosis as a regulator of antibody-dependent cellular cytotoxicity
Authors: Van Wagoner Carly M , Rivera-Escalera Fátima , Comeau Laurey Dea , Bauchle Casey , Chu Charles C , Zent Clive , Elliott Michael Rusty 
Published: January 2023

Abstract
While monoclonal antibodies (mAb), such as αCD20, have significantly improved patient outcomes for B cell malignancies, patient responses vary and drug resistance can occur. One proposed limitation is the reduction of innate immune effector functions such as antibody dependent cellular phagocytosis (ADCP) – the principal cytotoxic mechanism for many mAb-based therapeutics. ADCP is mediated by Fcγ Receptor- and complement-dependent pathways (FcγR-ADCP and cADCP, respectively). However, our lab has shown that the capacity of macrophages (Mϕ) to engulf mAb opsonized targets is finite and after brief period of engorgement, Mϕ enter a phase of negligible phagocytic activity termed hypophagia. We have previously described the mechanisms that negatively regulate FcγR-ADCP, but complement-induced hypophagia is less understood. To begin to characterize complement-induced exhaustion, we used live cell imaging to measure mAb opsonized thymocyte engulfment by primary mouse Mϕ in the presence absence of complement. Preliminary data suggest that cADCP kinetics and cytotoxic capacities are distinct from FcγR-ADCP; however, both lead to a hypophagic state that impinges on future target cell clearance. Furthermore, Mϕ refractory to additional FcγR-ADCP still phagocytose through complement receptors up until the cADCP pathway also becomes exhausted. Published data from our lab also show that FcγR driven hypophagia involves surface receptor downregulation, but interestingly, there is no reduction in complement receptor surface levels following cADCP-induced hypophagia. Therefore, a better understanding of cADCP and the mechanistic overlap with FcγR-ADCP is critical to optimizing mAb therapy by minimizing immune cell exhaustion.
Supported by grants from NIH (T32 AI007496, 26A1)
The effects of fragmented sleep on monocyte and neutrophil distribution within the tissues during atherosclerosis
Authors: Moriarty Alina K , Keeter William Coles , Ma Shelby , Stahr Natalie , Hatler Julian , Wellman Laurie , Sanford Larry , Galkina Elena 
Published: January 2023

Abstract
Atherosclerosis is a chronic inflammatory disease of large and medium size vessels that progresses across a lifespan and has been extensively linked to insufficient sleep. Poor fragmented sleep quality is strongly associated with all-cause mortality. Accumulating evidence demonstrates the independent effects of atherosclerosis and fragmented sleep on chronic inflammation within multiple tissues. However, there is limited data on the combined effects of sleep fragmentation (SF) and atherosclerosis on the inflammatory environments of multiples tissue. To address this question, we used flow cytometry and qPCR to investigate immune alterations within the peripheral blood, bone marrow, spleen, aorta, small intestine, and brains of female Apoe−/− mice following 12 weeks of high fat diet (HFD) feeding and SF. SF was induced by waking up mice at the day time using a moving bar. Importantly, we used an activity control (AC) group of mice that had a moving bar during nighttime. We found that chronic SF accelerated atherogenesis and induced increased myelopoiesis. Particularly, we detected increases in pro-inflammatory monocytes and neutrophils in the bone marrow, blood, spleen, aortas and small intestines of SF vs AC groups of HFD-fed female Apoe−/− mice. Additionally, we detected increase inflammatory markers in the brains of SF vs the control AC mice. Our data suggests that SF accelerates atherosclerosis and alters the immune composition of multiple tissues including the blood, bone marrow, spleen, small intestine, and aorta of atherosclerosis-prone mice. Furthermore, the increased peripheral monocytosis and neutrophilia may serve as a link to the elevated inflammatory markers in the brains of HFD-fed, female SF Apoe−/− mice.
Supported by the American Heart Association Pre-Doctoral Fellowship (20PRE35180156)
Profiling adrenal gland resident macrophage response to acute and chronic stress
Authors: Xu Yingzheng , Gallerand Alexandre , Dolfi Bastien , Zhu Alisha , Schrank Patricia R , Patterson Michael T , Acharya Nisha , Zaitsev Konstantin , Ivanov Stoyan , Williams Jesse W 
Published: January 2023

Abstract
Macrophages are found across all organs in the body and play key roles in health and disease. Systemic stress is a major risk factor for a variety of chronic inflammatory diseases. However, the primary source for stress hormones, the adrenal gland (AGs), have yet to be thoroughly assessed for immune cell diversity. Here we utilized single cell RNA-sequencing (scRNA-seq) to investigate macrophage heterogeneity in nascent AGs, compared against acute stress (cold challenge) or a chronic stress model of cardiovascular disease. In steady state, we observed two major macrophage populations in the AG. Following acute and chronic stress, AG macrophages upregulated expression of inflammatory cytokines (Il1b, TNFa) and key lipid uptake molecules, including Trem2. These observations were replicated using imaging analysis showing hormone uptake by AG macrophages. Using a monocyte-fate-mapping approach, we observed increased recruitment following stressed conditions, which correlated with reduced AG macrophage proliferation. Finally, we observed exacerbated systemic corticosterone levels following AG macrophage depletion and Trem2 deficiency. Overall, these data define AG macrophage heterogeneity and suggest a regulatory function of AG macrophage following exposure to acute and chronic stress.
Glycogen pathway intermediate uridine diphosphate glucose alters dendritic cell mitochondrial respiration in a nitric oxide-dependent manner
Authors: Vagher Bay L , Amiel Eyal 
Published: January 2023

Abstract
Dendritic cells (DCs), the professional antigen presenting cells of the immune system, undergo metabolic reprogramming in response to stimulation through Toll-Like Receptors (TLRs). Our lab and others have shown that metabolic reprogramming in DCs is accompanied by increased reliance on glycolytic metabolism through use of glucose and glycogen as fuel. Both metabolites are required by DCs to perform immune functions associated with activation including secretion of cytokines, upregulation of costimulatory molecules, and initiation of the T cell-mediated immune response. While our lab has published that glycogen is required within 4–8 hours after activation, production of nitric oxide (NO) regulates many metabolic processes during the later stages of activation via NO-dependent suppression of mitochondrial respiration. Recent studies have shown that glycogen pathway intermediate uridine diphosphate glucose (UDPG) is continually elevated in inflammatory macrophages past 24 hours of activation. Additionally, UDPG can be exported extracellularly and act as an autocrine signaling molecule to increase proinflammatory gene expression. We tested the hypothesis, that, like inflammatory macrophages, DCs elevate production of UDPG in response to activation and that this metabolite can bolster NO-mediated processes during DC activation. To investigate the role of UDPG in DCs, we characterized DC mitochondrial respiration in response to activation by LPS and the addition of exogenous UDPG. Additionally, we performed functional assays to assess NO production, cytokine secretion, as well as inflammatory gene expression to begin elucidating an axis by which UDPG and NO work together to regulate DC metabolism and immune function.
Supported by grants from UVM (COBRE VCIID Funding Support and Pilot Project) and NIH (NIAID 1R21AI135385-01A1)
Influenza A virus modulates ACE2 expression and SARS-CoV-2 infectivity in human cardiomyocytes
Authors: Rajaram Murugesan , Wu Qian , Kumar Naresh , Salijoughian Noushin , Zani Ashley , Patton Ashley , Ganesan Latha , Yount Jacob , Lafuse William 
Published: January 2023

Abstract
Influenza A virus (IAV) and SARS-CoV-2 are both acute respiratory viruses currently circulating in the human population. Prior IAV infection enhances SARS-CoV-2 infectivity and lung pathogenesis in mice; however, underlying mechanisms and the extent that co-infection leads to involvement of other organs in disease severity remains unknown. Herein, we investigated the impact of prior IAV infection on SARS-CoV-2 pathogenesis and cardiomyocyte function. IAV infection induces the expression of ACE2 in human lung epithelial cells, lung fibroblasts, macrophages, cardiac fibroblasts (HCFs), and hiPSC-Cardiomyocytes (CMs). Interestingly, we detected poorly glycosylated ACE2 in lung epithelial cells and cardiac fibroblasts. In contrast, expression of a heavily glycosylated form of ACE2 is induced by IAV in CMs. In all cell types, IAV infection enhances SARS-CoV-2 viral entry. However, efficient SARS-CoV-2 replication was uniquely inhibited in CMs. Glycosylation of ACE2 correlated with enzymatic conversion of its substrate Angiotension II, induction of eNOS and nitric oxide production, providing a mechanistic underpinning for restricted viral replication in CMs. Our results indicate that IAV-mediated induction of ACE2 is double-edged, providing increased risk for SARS-CoV-2 coinfection in epithelial cells and HCFs, while limiting SARS-CoV-2 replication in CMs. We conclude that differential glycosylation of ACE2 may be a molecular determinant, not of SARS-CoV-2 infection, but of replication.
Funding: NIH grants R01-AI 146252, R21-AI 146690
Funding: NIH grants R01-AI 146252, R21-AI 146690
Defining complex mechanistic interactions and responses by macrophages during Mycobacterium abscessus infection
Authors: Gilliland Haleigh , Olive Andrew 
Published: January 2023

Abstract
Phagocytosis by macrophages is critical to eradicate invading pathogens. Phagocytosis is regulated by parallel networks that control the binding and uptake of particles, subsequent lysosome delivery, and activation of downstream innate immune responses. However, whether distinct host pathways drive unique responses to targeted substrates within the lung environment remains unknown. Mycobacterium abscessus (MAB) is a rapidly growing non-tuberculous mycobacterium that infects patients with chronic lung diseases, like cystic fibrosis. While interactions between MAB and macrophages contribute to its pathogenesis, how macrophages bind, phagocytose, and control MAB remains entirely unclear. We hypothesize that understanding key MAB-macrophage interactions will identify critical host targets that can be inhibited to prevent disease. To test this hypothesis, using a genome-wide knockout library of immortalized bone marrow derived macrophages, we completed a forward genetic screen to identify host pathways that contribute to fluorescent MAB uptake. Our results show glycosaminoglycan synthesis (sGAGs) in macrophages is required to efficiently take up MAB. Both enzymatic and genetic approaches found key sGAG biosynthesis regulators, UGDH, B3GLCT, B4GALT7 and B3GAT3, influence macrophage interactions with MAB and other pathogens like Mycobacterium tuberculosis. Using a recently developed alveolar macrophage model, we are now dissecting the role of sGAGs in lung specific macrophages. Future work will determine how sGAG pathways modulate bacterial replication, cytokine responses and disease progression following MAB infection with the goal of defining key mechanisms driving host-pathogen interactions in the lungs.
CD3ζ adaptor structure determines functional differences between human and mouse CD16 Fc-gamma receptor signaling in natural killer cells
Authors: Aguilar Oscar A , Fong Lam-Kiu , Ishiyama Kenichi , DeGrado William F , Lanier Lewis L 
Published: January 2023

Abstract
Natural killer (NK) cells are innate lymphocytes capable of distinguishing between healthy and pathogenic cells using a myriad of receptors expressed on their cell surface. The CD16 receptor detects the Fc portion of IgG on antibody-coated cells resulting in NK cell activation. The importance of this receptor on human NK cell biology has long been appreciated; however, how CD16 functions in mouse NK cells remains poorly understood. Here, we report drastic differences between human and mouse CD16 functions in NK cells. We demonstrate that one of the adaptor molecules that CD16 associates with and signals through, CD3ζ, plays a critical role in these functional differences. Using a systematic approach, we demonstrate that key residues in the transmembrane domain of the mouse CD3ζ molecule prevent efficient complex formation with mouse CD16, thereby dampening receptor function. Mutating these residues in mouse CD3ζ to those encoded by human CD3ζ resulted in rescue of CD16 receptor function.
Supported by grants from the Cancer Research Institute (CRI), Burroughs Wellcome Fund (BWF), the Parker Institute for Cancer Immunotherapy (PICI) and NIH grants AI068129 and AI146581.
LncRNA U90926 is induced in activated macrophages, encodes a novel secreted protein, and is protective in endotoxic shock
Authors: Krementsov Dimitry N , Sabikunnahar Bristy , Caldwell Sydney , Varnum Stella 
Published: January 2023

Abstract
Thousands of long non-coding RNAs (lncRNAs) are encoded in mammalian genomes, yet the majority of them remain uncharacterized. In previous studies, we identified a mouse lncRNA of unknown function called U90926, expressed in activated macrophages. Here, we functionally characterized this gene in vitro and in vivo. Analysis of U90926 RNA levels revealed minimal expression across multiple tissues at steady state. However, the expression of this gene is highly induced in myeloid cells by toll-like receptor activation, in a p38 MAP kinase and MYD88-dependent manner. To study the function of U90926, we generated U90926-deficient (U9-KO) mice. Surprisingly, we found minimal effects of U90926 deficiency on gene expression in cultured macrophages. Given this lack of a macrophage-intrinsic effect, we investigated the subcellular localization of U90926 transcript and its protein-coding potential. We found that U90926 RNA localizes to the cytosol, associates with ribosomes, and contains an open reading frame that encodes a novel protein (termed U9-ORF). U9-ORF contains an ER signal peptide sequence, traffics to the Golgi, and is secreted from the cell. In vivo, the LPS endotoxemia model showed that U9-KO mice exhibited increased sickness responses and mortality in comparison with WT mice. Mechanistically, serum levels of IL-6 were elevated at in U9-KO mice compared with WT, and IL-6 neutralization improved sepsis outcome in U9-KO mice. Taken together, these results suggest that the protective effect of U90926 expression during endotoxic shock is orchestrated by regulating IL-6 levels, likely mediated by the paracrine and/or endocrine actions of the novel U9-ORF peptide secreted by activated myeloid cells.
Supported by grants from the NIH (R21AI151116 to DNK and P30GM118228 to Dr. Ralph Budd).
Glutamine addiction in NKT cells is regulated by AMPK-mTORC1 axis
Authors: Kumar Ajay , Yarosz Emily Lynn , Andren Anthony , Zhang Li , Lyssiotis Costas , Chang Cheong-Hee 
Published: January 2023

Abstract
Cellular metabolism is essential in dictating conventional T cell development and function, but its role in natural killer T (NKT) cells has not been well studied. We have previously shown that NKT cells operate distinctly different metabolic programming from CD4 T cells, including a strict requirement for glutamine metabolism to regulate NKT cell homeostasis. However, the mechanisms by which NKT cells regulate glutamine metabolism for their homeostasis and effector functions remain unknown. In this study, we report that steady state NKT cells have higher glutamine levels than CD4 T cells and NKT cells increase glutaminolysis upon activation. Among its many metabolic fates, NKT cells use glutamine to fuel the tricarboxylic acid cycle and glutathione synthesis, and glutamine-derived nitrogen enables protein glycosylation via the hexosamine biosynthesis pathway (HBP). Each of these functions of glutamine metabolism was found to be critical for NKT cell survival and proliferation. Furthermore, we demonstrate that glutaminolysis and the HBP differentially regulate IL-4 and IFNg production. Finally, glutamine metabolism appears to be controlled by AMP-activated protein kinase (AMPK)-mTORC1 signaling. These findings highlight a unique metabolic requirement of NKT cells which can be potentially serve as an effective immunotherapeutic agent against certain nutrient restricted diseases.
This work was supported in part by National Institutes of Health Grants R01 AI121156 and R01 AI148289 (to C-H.C.).
Influence of estradiol deficiency on the acute inflammatory response following a traumatic skeletal muscle injury
Authors: McMillin Shawna L , Noel Richard , O’Farrell Laura , Warren Gordon , Lowe Dawn 
Published: January 2023

Abstract
Estradiol (E2) influences the inflammatory response. Research has shown that skeletal muscle chemokine mRNA expression and neutrophil infiltration after a traumatic freeze injury are blunted in ovariectomized mice treated with placebo compared to E2-treated mice. How E2 deficiency alters the acute muscle inflammatory response is unclear with potential mechanisms including alterations in the number of circulating leukocytes, leukocyte chemotaxis, and/or muscle chemokine expression. To investigate these possibilities, female C57BL/6J mice underwent a sham or ovariectomy (OVX) surgery, 21–28 d later tibialis anterior (TA) muscles were freeze injured. TA muscles and blood were collected 24 h post injury. Total white blood cell (149%) and monocytes (427%) were elevated in OVX compared to Sham mice but there was no difference in the neutrophil counts (p≥0.64). To determine if E2 deficiency impacts leukocyte chemotaxis, isolated leukocytes from bone marrow of non-injured Sham or OVX mice were placed in a transwell migration assay. OVX leukocytes had greater chemotaxis towards CXCL1 (37%), CXCL2 (43%), and CXCL5 (27%) than Sham. To examine if E2 deficiency alters muscle CXCL1 and CXCL5 protein content contributing to chemotaxis, ELISA assays were performed. Surprisingly, muscle CXCL1 and CXCL5 contents were similar between OVX and Sham. Collectively, mice lacking E2 have relatively high blood leukocytes and chemotaxis suggesting a greater acute inflammatory response which appears not to be driven by changes in muscle chemokine expression. Additional studies need to consider possible negative regulators of the acute inflammatory response in OVX muscle.
Supported by DAL and GW (R01AG031743 & R01AG062899), and SLM (T32AR007612)
Brain resident memory CD8+ T cells trigger CNS immune activation and infiltration
Authors: Musial Shawn C , Searles Tyler G , Kleist Sierra A , Degefu Hanna N , Isaacs Jordan F , Skorput Alexander G , Rosato Pamela C 
Published: January 2023

Abstract
The shifting paradigm regarding immune surveillance of the central nervous system (CNS) has shed light on immune cell networks thought to be absent from healthy brain tissue. Resident memory T cells (TRM) are a unique subset of memory T cells that persist within non-lymphoid tissues to provide rapid onset protection against reinfection. Recently, brain TRM (bTRM) have been identified in humans, with CNS or peripheral infection, or vaccination leading to bTRM establishment in mice. While bTRM are important for protection of the CNS against reinfection, their regulation and involvement in shaping the neuroimmune landscape remains unknown. Here, we take a reductionist approach employing viral-derived peptides to show that CD8+ bTRM reactivation is sufficient to initiate a cascade of innate and adaptive immune activation in the brain. Specifically, bTRM reactivation triggered activation of NK cells, T cells, microglia, and induced dendritic cell (DC) maturation, including upregulation of lymph node homing molecules. Reactivated bTRM also promoted accumulation of DCs in draining lymph nodes, and macrophages, monocyte-derived DCs, T cells and NK cells in the brain. Our preliminary data suggests that PD-1:PD-L1 signaling regulates the magnitude of this response, as PD-L1 blockade led to enhanced bTRM activation and neuroinflammation. We anticipate our results to illuminate roles for PD-1 signaling on bTRM in the context of pathogen clearance, and neurologic toxicities seen in cancer patients following PD-1 inhibitor treatment. This study will also provide insight into the pathologic or protective capacity of bTRM in neurologic diseases where T cells are implicated, such as Alzheimer’s disease, multiple sclerosis, and brain cancer.
Supported by grants from NIH (K22 AI148508-02, T32 AI007363)
Role of NF-kappaB c-Rel O-GlcNAcylation in the regulation of cytotoxic T cell function
Authors: Ramakrishnan Parameswaran , Centore Joshua T 
Published: January 2023

Abstract
Autoimmunity in type 1 diabetes (T1D) is primarily caused by destruction of insulin producing pancreatic beta cells by cytotoxic T cells, resulting in hyperglycemia. Adverse pathological effects of hyperglycemia include the increased O-GlcNAcylation of cellular proteins. We found that the transcription factor nuclear factor kappaB (NF-kB) subunit c-Rel is a target of O-GlcNAcylation at serine residue 350 in T cells. c-Rel is the major regulator of CD4 and CD8 T cell function and T regulatory cell development that controls autoimmunity and immunosuppression, respectively. c-Rel O GlcNAcylation increases the expression of pro-autoimmune cytokines and decreases the expression of the transcription factor forkhead box P3 (FOXP3) in CD4 T cells. However, the role of c-Rel O-GlcNAcylation in cytotoxic T cells remains unknown. The cell death pathways mediated by Fas ligand (FasL) and TNF-related apoptosis-inducing ligand (TRAIL) are major contributors of T cell mediated cytotoxicity. Our preliminary microarray study showed that FasL and TRAIL expressions are dependent on O-GlcNAcylated c-Rel. We also found that hyperglycemia and c-Rel O-GlcNAcylation enhances FasL expression in both CD4 and CD8 T cells. Mechanistically, O-GlcNAcylation enhances and a point mutation at S350 O-GlcNAcylation site prevents c-Rel binding to FasL promoter. Our future studies aim at studying how hyperglycemia-induced c-Rel O-GlcNAcylation enhances cytotoxic ligand expressions in T cells, augmenting their potential to destruct host cells in T1D. This study will define the critical role of c-Rel O-GlcNAcylation in cytotoxic T cell function, revealing a new molecular mechanism that could be targeted to control autoreactive T cell function in T1D.
P.R was supported by National Institute of Allergy and Infectious Diseases at National Institute of Health grants R01 AI116730 and R21 AI144264, and National Cancer Institute at National Institute of Health grant R21 CA246194. JTC was supported by National Institute of Health NIH/NEI T32 pre-doctoral training grant T32EY007157.