bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lnk/Sh2b3 modulates bioenergetic metabolism of activated CD8 T cells and control the development of Type 1 Diabetes
Authors: Pant Tarun , Foda Bardees , Geurts Aron , Chen Yi-Guang 
Published: August 2023

Abstract
Recent genome-wide association studies (GWAS) have shown a strong correlation between a genetic polymorphism in the SH2B3 gene and the development of autoimmune diseases, including type 1 diabetes (T1D). Lnk/Sh2b3 is an adaptor protein interacting with various intracellular proteins involved in JAK/STAT cytokine signaling of different cell types, including CD8 T cells. Additionally, Sh2b3-deficient CD8 T cells are hypersensitive to IL-15 stimulation. However, how reduced Sh2b3 function affects the molecular mechanisms that activate and sustain CD8 T cells promoting T1D development remains elusive. We hypothesized that genetic deletion of Sh2b3 in the non-obese diabetic (NOD) mouse would impact T1D incidence by altering T cell activation. NOD. Sh2b3−/− mice developed diabetes faster than wild-type controls. Additionally, Sh2b3-deficient CD8 T cells were hyperresponsive to IL-15 stimulation, promoting the generation of the activated CD44 high CD8 T cell population. Intriguingly, IL-15-stimulated Sh2b3−/− splenocytes possessed significantly higher mitochondrial respiratory capacity (SRC) and ATP synthesis than the wild-type counterparts. Furthermore, CD8 T cells of NOD. Sh2b3−/− mice showed increased expression of genes associated with mitochondrial biogenesis and oxidative metabolisms in response to in vitro IL-15 stimulation. Overall, our study supports a role of Sh2b3 in T1D development by regulating mitochondrial biogenesis and metabolism of IL-15-stimulated CD8 T cell. Our study provides new insight into the role of Sh2b3 in activating and sustaining the CD8 T cell response in the pathogenesis of T1D.
Funded by NIH DK097605
Funded by NIH DK097605
Knockout CD73 reduces thymus-derived lymphocytes and clinical phenotype of Foxp3+Treg deficient autoimmune scurfy mice
Authors: Liu Yuying , Okeugo Beanna , Armbrister Shabba A , Daniel Rhea C , Saleh Zeina M , Rhoads J Marc 
Published: August 2023

Abstract
CD73 is ubiquitously expressed and regulates critical functions across multiple organ systems. The combination of CD39 and CD73 degrade ATP to adenosine that shifts ATP-driven pro-inflammatory immune cell activity toward an anti-inflammatory state. This immunological switch is a major mechanism for Tregs to control inflammation. In the Foxp3+Treg deficient scurfy (SF) mouse, a mouse model of human IPEX syndrome, we showed that a specific probiotic exhibits therapeutic effects via probiotic-derived adenosine. We generated CD73KOSF mice by removing host CD73, aiming to identify a specific probiotic-CD73 effect. CD73KOSF mice were generated by breeding heterozygous-Foxp3sf/J females to CD73KO male mice with genotyping confirmation. We unexpectedly observed that KO of CD73 in SF mice reduced clinical severity. CD73KOSF mice showed reduced ear thickness, increased ear size, improved deformed ears, and reduced scurfy skin compared to SF mice. SF mice had increased CD4+ and CD8+ T cells compared to WT mice; KO of CD73 in SF mice significantly reduced the numbers of these cells in the spleen and blood to normal. However, the inflammatory cytokines and chemokines in plasma and lymphocyte infiltration in the liver of CD73KOSF were similar to those in SF mice. We further identified that KO of CD73 in SF mice reduced the numbers of CD3+T and DP CD4+CD8+ T cells in the thymus compared to those in SF mice, indicating that reducing clinical phenotype specifically scurfy tails and deformed ears may mainly be due to reduced central and peripheral lymphoproliferation. This study provides data to aid further discovery of CD73 as a target to improve dermatitis-one of the most common symptoms in Treg-deficiency-associated primary immune deficiencies.
Supported by grants from NIH/NIAID (R03AI153725)
Modulation of murine lupus by Aconitate Decarboxylase 1
Authors: Martinez Eduardo Patino , Nakabo Shuichiro , Claybaugh Dillon , Romero Aracely , Blanco Luz P , Kaplan Mariana J 
Published: August 2023

Abstract
Mitochondrial synthesis of itaconate by myeloid cells (monocytes and macrophages) is mediated by the TCA cycle enzyme Aconitate Decarboxylase 1 (Acod1). Upregulation of Acod1–itaconate pathway, occurs after activation of various Toll-like receptors (TLRs) or cytokine stimulation (TNF or type I Interferons). While various anti-inflammatory effects of the Acod1 – Itaconate pathway have been previously reported (e.g. decreases in IL-6 and IL-1β synthesis) the contribution of impairments in endogenous itaconate synthesis in systemic lupus erythematosus (SLE) remain poorly characterized. First, we explored and characterized Acod1 expression in bone marrow or monocyte-derived macrophages (BMDM and MDM, respectively) following in vitro imiquimod (IMQ) treatment. Then, we investigated the role of endogenous itaconate modulation in the development and severity of TLR-7 induced lupus using the IMQ model. 10-week-old wild type and Acod1−/− mice were treated with topical IMQ cream for 5 weeks to induce an SLE phenotype. We found that Acod1 protein expression is induced in BMDM and MDM after 12 hours of IMQ stimulation, and this induction is partially dependent on IFNRa1 signaling. Moreover, Acod1−/− BMDM treated with IMQ for 12 h displayed higher mRNA expression of il6, il1b, il18, ccl2, cxcl2, and cxcl9, together with an increase in pro-IL-1β protein levels. IL-6 and IL-1β production were also increased. After 5 weeks of in vivo IMQ topical treatment, Acod1−/− mice have a higher concentration of circulating anti-dsDNA autoantibodies but a decrease in splenomegaly compared to the treated WT mice. These results, demonstrate a putative role for endogenous Acod1-itaconate pathway in the regulation of autoimmunity.
This work is support by the NIH/NIAMS Intramural Research Program
Combining activity-based protein profiling and flow cytometry to elucidate the role of lipid-metabolizing enzymes in cell heterogeneity
Authors: McSorley Caitlin , Murtagh Olivia , Hsu Ku-Lung 
Published: August 2023

Abstract
Cell metabolism is mediated by intracellular enzymes that supply essential and specific molecular cues needed to initiate the differentiation of homogenous cell populations into heterogenous cell populations. Intracellular enzymes involved in the metabolism of lipids are of particular interest as lipids play key roles in cell signaling and differing lipid-metabolizing enzyme activity may produce varying signaling profiles, and thus, a varying cell phenotype. To understand how these enzymes regulate function at the single-cell level, we aim to develop methodology that combines activity-based protein profiling (ABPP) and flow cytometry to allow for the separation of heterogenous cells into new populations based on enzyme activity. Our initial studies have focused on targeting serine hydrolases, as this family of enzymes includes numerous intracellular lipases involved with the metabolism of lipids. We have synthesized a modified activity-based fluorescent probe containing a triazole urea warhead known to label active serine hydrolases in live cells. Based on the fluorescent profile generated by measuring single cell fluorescence using flow cytometry, the probe targeted a select population of cells when compared to a control probe and unlabeled cells. This probe-labeled population was concentration dependent as higher concentration of probe labeled more enzyme, suggesting that a different population of cells could be collected between two different concentrations. After these cells are sorted based on the differing fluorescent signals, these new subsets will be analyzed via targeted lipidomics and proteomics methods to quantity any differences in the probed intracellular enzyme expression.
This work was supported by the National Science Foundation CAREER Award no. 1942467.
A new antibody for the study of human CD157 expression and function
Authors: Kassmer Susannah H , Divekar Anagha , Chen Weihao , Yang Xifeng 
Published: August 2023

Abstract
CD157 is an ectoenzyme that has both cyclic ADP-ribose hydrolase and ADP-ribosyl cyclase activities. In the human hematopoietic system, CD157 is prevalently expressed by cells of the myelomonocytic lineage, and interacts with extracellular matrix components and regulates leukocyte diapedesis via integrin-mediated signaling. CD157 is implicated in the pathophysiology of several neurological disorders.
Although it lacks a cytoplasmatic domain, CD157 is able to transduce intracellular signals by establishing functional and structural crosstalk with β1 (CD29) and β2 (CD18) integrins. CD157 ligation causes integrin– dependent cytoskeletal remodeling and increase in F-actin content. Activation of downstream signaling pathways leads to cell polarization, with CD157 migrating prevalently to the rear of the cells whereas F-actin is localized at the opposite pole. However, the molecular and cellular functions of CD157 still remain poorly understood.
Here, we describe the generation of a monoclonal antibody specific for human CD157 (clone W21007F) that can be used in flow cytometry, immunofluorescence and blocking of CD157 mediated adhesion of monocytes to fibronectin. Treatment of the pro-monocytic, myeloid leukemia cell line U937 with clone W21007F induces cell polarization and a marked increase in filamentous actin, with CD157 clustering at the uropod. The majority of F-Actin fibers are located at the opposite end of CD157, and CD157 co-localizes with integrin beta-1 in distinct membrane domains. The reference clone SY/11B5 and isotype control antibody do not show this effect. In conclusion, anti-human CD157 (clone W21007F) is a valuable tool for the study of CD157 function and expression in human cells.
Staphylococcus aureus promotes increase IL-1 mediated immunopathology and delayed healing in cutaneous leishmaniasis
Authors: Amorim Camila Farias , Lovins Victoria , Singh Tej P , Novais Fernanda O , Harris Jordan , Carvalho Lucas P , Carvalho Edgar M , Beiting Daniel P , Grice Elizabeth A , Scott Phillip 
Published: August 2023

Abstract
The chronic infection by Leishmania braziliensis causes a skin barrier (ulcer) breach and is susceptible to secondary bacterial infections. The development of the ulcer is associated with a dysregulation of the skin microbiome, which we hypothesized impacts host gene expression, exacerbates the inflammatory response, and prolongs the resolution of the disease. We conducted an integrative multi-omics meta-analysis of the skin microbiome, host gene expression, and clinical metadata of patients. We found that a high bacterial burden was associated with an increased inflammatory response and delayed healing. 16S-seq analysis of lesion swabs revealed that while patients exhibit several distinct skin microbiomes, a microbiome dominated by Staphylococcus is the most common. Furthermore, the patients with a dominant lesional Staphylococcus microbiome were delayed in healing compared to those with a heterogeneous microbiome. Since we found that S. aureus was a common isolate from the ulcers, we carried out dual RNA-seq analysis on the lesion biopsies to quantify S. aureus transcriptional abundances and associated them with host gene expression. High S. aureus transcript abundance was associated with delayed healing and increased expression of IL-1α and IL-1β. These cytokines were critical for modulating disease outcome since pathology was reduced when we neutralized either in L. braziliensis-infected mice colonized with S. aureus. These results indicate that an altered skin microbiome develops in cutaneous leishmaniasis, influencing responsiveness to anti-parasitic drug treatment. They suggest that host-directed therapies designed to reduce the bacterial burden in leishmanial lesions may be therapeutic.
NIH (AI143790)
Distinct lymphatic remodeling is associated with healing and non-healing murine cutaneous leishmaniasis
Authors: Fry Lucy , Bowlin Anne , Roys Hayden , Weinkopff Tiffany 
Published: August 2023

Abstract
Cutaneous leishmaniasis (CL) is the spectrum of diseases caused by Leishmania parasites endemic to the tropical and subtropical regions of the world causing 1–2 million new cases each year. Based on the species of infecting parasite and the host immune status, CL can be self-healing or lead to permanent disfiguration. We showed a critical role for the lymphatics in wound healing during L. major infection in C57BL/6 mice, a self-healing model of CL that replicates most human disease. Specifically, lymphangiogenesis, mediated by vascular endothelial growth factor-A (VEGF-A)/vascular endothelial growth factor receptor-2 (VEGFR-2) signaling, is required for efficient lesion resolution. The lymphatic vasculature regulates the immune response to infection, transporting soluble antigen and antigen presenting cells to the lymph nodes and engaging an active role by modulating inflammatory immune cell exit from the site of infection. Here, we investigate the role of the lymphatics in mice infected with L. amazonensis and L. mexicana, species causing non-healing CL. We found that the mediators of lymphangiogenesis like VEGF-A and VEGF-D are elevated during infection with L. amazonensis and L. mexicana, but they are either delayed or not sustained over time which compromises lymphangiogenesis and increases vessel dilation compared to naïve mice. During Leishmania infection we find increased lymphatic vessel dilation is associated with enhanced disease severity. Taken together, the current work suggests lymphangiogenesis is attenuated later during infection with species causing non-healing CL suggesting impaired lymphatic remodeling contributes to persistent lesions in patients with CL.
COBRE UAMS CMPHIR
γδ T Cells Contribute to Immunopathology During Neonatal Sepsis in an Age-Dependent Manner
Authors: Witt Lila T , Greenfield Kara , Knoop Kathryn 
Published: August 2023

Abstract
Bacterial bloodstream infections (BSIs) remain a significant contributor to neonatal mortality, despite improved hygienic practices in the NICU. Although the understanding of the neonatal immune system has increased greatly over the past decade, why neonates, but not older infants, are susceptible to severe adverse immunopathology – sepsis – in response to bacteremia remains poorly understood. In the present study, we find that postnatal day 5 (P5) neonatal γδ T cells are highly inflammatory during a mouse model of E. coli BSI and are associated with mortality. Furthermore, γδ T cells in P5 mice rapidly produce pro-inflammatory cytokines, such as IFN-γ, IL-17A, and TNFα, and increase their expression of cytotoxic molecules such as granzyme and perforin. Interestingly, blockade of the γδ TCR in vivo is associated with increased survival and decreased pro-inflammatory cytokine production in P5 pups. Signaling and activation via the γδ TCR was confirmed using Nur77-GFP mice, with P5 γδ T cells significantly upregulating expression of Nur77 during in vivo infection. Intriguingly, E. coli BSI in P15 pups results in markedly different γδ T cells responses compared to neonates, despite similar systemic bacterial burden. During bacterial bloodstream infection, P15 pups do not experience mortality, and unergo minimal activation of γδ T cells and production of IFN-γ, IL-17A, and TNFα. Furthermore, BSI infection in P15 Nur77-GFP mice revealed lack of TCR signaling in P15 γδ T cells at this age. In conclusion, the present study reveals rapid age-dependent changes to γδ T cell responses during early life and suggests neonates may be uniquely susceptible to γδ T cell-mediated immunopathology during bacterial bloodstream infection.
T32 AI170478-01
EnvZ/OmpR two-component system induces antibiotic resistance in Salmonella enterica Serovar Enteritidis in response to β-lactams
Authors: Ko Duhyun , Choi Sang Ho 
Published: August 2023

Abstract
Outer membrane porins (OMPs) of Gram-negative bacteria including Salmonella enterica serovar Enteritidis allow the entry of small hydrophilic antibiotics. S. Enteritidis is a human pathogen causing food-borne illnesses, and infection by S. Enteritidis often results in severe invasive disease and requires antibiotic treatments. Although compositional modulation of OMPs is frequently observed in multidrug-resistant S. Enteritidis, little is known about the mechanisms by which the pathogen modulates OMP composition to enhance antibiotic resistance. Here, we found that the S. Enteritidis strain with an active state of EnvZ/OmpR two-component system is highly resistant to various antibiotics, especially β-lactams. Transcriptome analysis showed that the active state of EnvZ/OmpR induces differential expression of multiple OMP genes, including SEN1522, SEN2875, ompD, and ompW. Interestingly, the cellular level of response regulator OmpR determines the expression of the four OMP genes, and phosphorylation of OmpR is not necessary for the regulation of ompD and ompW. Phenotypic analysis revealed that ompD is a key OMP gene responsible for the EnvZ/OmpR-mediated antibiotic resistance in S. Enteritidis. Notably, EnvZ/OmpR responds to the presence of β-lactams and provides S. Enteritidis with direct benefits for survival. Altogether, this study suggests that EnvZ/OmpR remodels OMP composition of S. Enteritidis in response to β-lactams and enhances antibiotic resistance.
This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education (NRF-2022R1A6A3A01086815).
CD8+ T cells require CCR5 expression to mediate immunopathology in cutaneous leishmaniasis
Authors: Sacramento Lais A , Amorim Camila Farias , Lombana Claudia , Scott Phillip 
Published: August 2023

Abstract
Cytolytic CD8+ T cells mediate immunopathology in cutaneous leishmaniasis by a mechanism dependent on degranulation and lysis of Leishmania-infected cells, culminating in NLRP3 activation and IL-1b release. Here, we sought to identify chemokine receptors involved in CD8+ T cell migration to the lesion that could be employed as a treatment target to ameliorate disease severity. A transcriptional study identified the profile of chemokine receptors that predicts treatment failure in Leishmania braziliensis patients and identifies possible targets that may be involved in CD8+ T cell migration. Using murine models of cutaneous leishmaniasis, we found that around 20% of CD8+ T-cells express CCR5 in lesions at the peak of the disease. In previous studies, we found that CD8+ T cells transferred to Rag1−/− mice mediated increased NLRP3 and IL-1b dependent disease. Therefore, to test if CCR5 expression on CD8+ T cells was involved in their migration to lesions, we transferred wild-type or CCR5−/− CD8+ T cells to L. braziliensis infected Rag1−/− mice. While infected Rag1−/− mice reconstituted with wild-type CD8+ T cells developed severe pathology, Rag1−/− mice that received CCR5−/− CD8+ T cells developed smaller lesions accompanied by a significant reduction in the number of CD8+ T cells in the lesions. To test whether CCR5 blockade would control disease severity, we used maraviroc (MVC), a selective inhibitor of CCR5 approved by the FDA. MVC treatment significantly reduced lesion development without affecting parasite number in our murine models. Collectively, these results demonstrate that cytolytic CD8+ T cells migrate to leishmania lesions in a CCR5-dependent manner, and MVC treatment efficiently prevents CD8+ T-cell mediated pathology.
R01 AI106842 and U01 AI08865006
Gut regulatory T cells mediate immunological tolerance in Salmonella-infected super-spreader hosts
Authors: Di Luccia Blanda , Massis Liliana Moura , Ruddle Sarah , Narasimhan Ramya , Pham Trung Hoang Minh , Vilches-Moure Josè , Amieva Manuel R , Monack Denise M 
Published: August 2023

Abstract
Salmonella Typhimurium is an enteric pathogen that causes gastroenteritis in humans and Typhoid fever-like symptoms in mice. Our lab has shown that oral infection of 129X1/SvJ mice with Salmonella Typhimurium results in ~25% of mice becoming persistent high-shedders (&gt;108 CFU/g feces). Because these mice can transmit infection to a naïve host, we refer to them as super-spreaders (SS). Unexpectedly, SS mice are asymptomatic despite a persistent high-pathogen burden in the gut. We hypothesized that SS mice are disease resistant due to a gut-specific immune state that facilitates homeostasis between host and pathogen. To examine this, we performed extensive immuno-phenotyping of SS mice, which revealed a distinct type-1 immune state in the gut. We found that IFNγ producing effector CD4 T cells were the dominant population to accumulate in SS guts. Additionally, a population of Tbet+ Tregs were found only in the gut of SS mice, suggesting these cells may enable the SS asymptomatic state. Accordingly, specific ablation of Tregs resulted in a dramatic weight loss, gut inflammation, and a compromised epithelial barrier in SS mice. Bacterial burden was unchanged in Treg depleted mice, demonstrating that morbidity was not caused by Salmonella burden but likely due to immune pathology. Indeed, depletion of effector CD4+ T cells in Treg-deficient SS mice reversed this morbidity, confirming the disease state was directly caused by immune pathology. These results demonstrate that in SS mice Tregs play an essential tolerogenic role maintaining intestinal homeostasis. We are currently investigating the immunological mechanisms triggering this effect and whether this new immune-adapted state may impact infections with other enteric pathogens.
Giardia duodenalis potentiates macrophage IL-10 production in response to LPS
Authors: Singer Steven M , Miskovsky Eleanor , Darmadi Matthew , Menegas Samantha , Shapiro Danielle , Fink Marc , Angelova Vanessa V 
Published: August 2023

Abstract
Giardia duodenalis is one of the world’s most common intestinal parasites, with an estimated 280 million cases globally each year. Infections can cause diarrhea and cramps, although they are often subclinical. Interestingly, Giardia can have a protective effect and reduce the incidence of fatal diarrhea in co-infections with other enteric pathogens. In this study, we investigate the anti-inflammatory response to Giardia via the macrophage galactose lectin-type 1 (MGL1) receptor. Our reasons for choosing this receptor are three-fold: it is expressed on macrophages and some dendritic cells and plays a role in immune response to other pathogens, it has been shown to induce anti-inflammatory effects in the DSS colitis model, and it demonstrably binds galactose-containing carbohydrates, like the N-Acetylgalactosamine (GalNAc) present in the cell wall of Giardia cysts. We show that peritoneal macrophages isolated from wildtype C57BL/6 mice produce markedly more of the anti-inflammatory cytokine IL-10 when stimulated with lipopolysaccharide (LPS) and Giardia extract compared to LPS alone. The potentiated IL-10 response to Giardia is lost in peritoneal macrophages isolated from MGL1 receptor knockout mice or in extracts centrifuged at 10,000 X g. Elucidating this anti-inflammatory pathway not only promises a better understanding of giardiasis, which disproportionately affect lower-middle income communities. also might present opportunities to mimic the parasite in the treatment of a wide array of inflammatory diseases.
Supported by a grant from NIH (R15 AI109591).