bluuebunny/crossref_metadata_2025_split huggingface dataset:
Liver-specific programming of myeloid cells promotes intrahepatic immunosuppression
Authors: Guha Prajna , Gardell Jillian , Lopes Mikayla , Espat N. Joseph , Katz Steven C. 
Published: January 2023

Abstract
Liver is a tolerogenic organ and has variety of immune cells resulting in a profoundly immunosuppressive space. We recently reported that GM-CSF/JAK2/STAT3 axis drives liver myeloid suppressor cell (L-MDSC) proliferation and STAT3 inhibition causes activation of apoptosis signaling via Bax up-regulation. Herein, we explore liver specific programming events that promote L-MDSC suppressive conditioning. Bone marrow derived MDSC (BM-MDSC) were expanded in CD45.1+ mice in response to intraperitoneal MC38 tumors. CD45.1+ BM-MDSC were adoptively transferred into CD45.2+ recipient mice via tail vein (TV) or portal vein (PV). CD11b+ cells were harvested 48 hrs later from recipient liver and lungs. Liver from PV and lung from TV CD45.1+ MDSC recipients were compared. There was increased expansion of CD45.1+ MDSC (CD11b+Gr1+) in PV-liver as compared to TV-lung group (Liver-PV 45±3% vs. Lung-TV 15±2% vs. Tumor 43±3, p&lt;0.001, n=5) with increased numbers of the more immunosuppressive monocytic MDSC (M-MDSC) subtype in CD45.1+ transferred cells in liver as compared to lung (Liver-PV 61±4%, Lung-TV 40±3%, Tumor 58±3 p&lt;0.005, n=5). Enhanced pSTAT3 expression (mediator of MDSC expansion) in CD45.1+CD11b+Gr1+ cells in liver was observed as compared to lung (pSTAT3: Liver-PV 54±4, Lung-TV 30±5, p&lt;0.05 n=5). Quantitative PCR of MDSCs isolated from Liver-PV showed significantly decreased levels (8.5 fold, p&lt;0.05, n=4) of pro-apoptotic Bax protein as compared to Lung-TV indicating MDSC apoptosis resistance following conditioning in the liver. These data indicate that L-MDSCs are directed towards suppressive programming and blocking STAT3 may have clinical application for enhancing the efficacy of immunotherapy for liver tumors.
Spanning tree progression analysis of density normalized events (SPADE) identification of novel myeloid derived suppressor cells (MDSC) subsets
Authors: Talmadge James E. , Warkentin Phyllis , Briitton Holly , Klassen Lynell W. , Cole Kathryn 
Published: January 2023

Abstract
MDSC’s are a heterogeneous population of myeloid cells at various differentiation stages. The human MDSC phenotypes, are controversial and subdivided into macrophage (M-), granulocytic (G-) and immature (i-) MDSC’s. Our studies used a single staining tube with antibodies to linage markers (CD3, CD19 and CD56), HLA-DR, CD11b, CD14, CD15, CD16, CD33, CD45, PD-L1 and LOX-1. Mobilized lymphoma patient apharesis (CA) products provided a product with a high frequency of MDSCs compared to normal donor blood samples (PB). SSCA and FSA identified lymphocytes, granulocytes and monocyte populations. A total population (CD45+), MDSCs (Lin-HLA-DR-CD11b+CD14+, Lin-HLA-DR-CD11b+CD14-CD33+ and Lin-HLA-DR−CD11b+ CD15+) and non MDSC myeloid populations (Lin-HLA-DR+CD14+, Lin-HLA-DR+CD33+ and Lin-HLA-DR+ CD15+Lin-HLA-DR-11b-) were exported from FlowJo for Spade analysis. This identified 11 nodes with 4 MDSC sub-populations. Impressively, cells from the non-MDSC populations, including monocytes and granulocytes did not occur within these nodes. SPADE identified an M-MDSC, G-MDSC and two iMDSC subsets with an increased frequency in the CA samples. Increased expression of LOX-1 and CD16 occurred in CA MDSCs vs. PB. Intracellular staining for expression of NOS-2 and Arg-1 were consistent with the M and G-MDSC subsets. Node 7 mainly expressed M-MDSC’s with a low frequency of CD15 dull G-MDSC’s. The cell frequency for G-MDSC’s in node 7 was 1,334 for CA and 0 for PB with M-MDSC’s 1,079 and 43 respectively. Node 8 had a frequency (3,319) of G-MDSC’s for CA and 2,286 for PB with M-MDSC’s 188 and 15 respectively. In summary SPADE analysis can be used to cleanly identify MDSCs from monocytes and granulocytes and provide insight into novel MDSC subsets.
Profiling Mesenchymal Stem Cell Immunomodulation In Vitro
Authors: Bonnevier Jody L. , Finkel Dave , Galitz David , Andersen Marnelle , Klingenberg Sarah , Rivard Jim , Hammerbeck Christopher , Aho Joy 
Published: January 2023

Abstract
Mesenchymal stem cells (MSCs) are multipotent adult stem cells found in a variety of tissues, including bone marrow, adipose, and umbilical cord. Although MSCs have the ability to differentiate into a variety of cell types useful for regenerative medicine, their ability to modulate the immune system has been at the forefront in the clinic.
The mechanisms by which MSCs affect the immune system are not fully understood. This makes it difficult to design specific quality control measures for MSCs used for cell therapy as well as to understand what parameters are the most critical for their immunomodulatory abilities. This specific testing is important to determine batch-to-batch variability and to better forecast patient-to-patient efficacy. In this study, we demonstrate a workflow to investigate the effects of MSCs on immune cell subset populations. Human MSCs were co-cultured with human T cell subtypes (Th1, Th2, Th17, and Treg) that have been differentiated utilizing CellXVivo™ Differentiation Kits. Co-culture supernates are then analyzed via Proteome Profiler™ Antibody Arrays to screen for changes in cytokine levels, relative to MSCs cultured in the absence of T-cells. Analytes discovered to change in the screening arrays are then quantitated using Luminex® Assays. We hypothesize that these tools and techniques will allow for a better understanding of the mechanisms contributing to MSC immunomodulation and provide methods for routine quality control testing of MSC populations prior to clinical use.
Expression of Eos is critical for T regulatory cell (Treg) survival and function
Authors: Gokhale Ameya Sanjeev , Shevach Ethan M. 
Published: January 2023

Abstract
Eos is a transcription factor belonging to the Ikaros transcription factor family and is preferentially expressed in Treg and activated T-conventional (T conv) cells. Our previous studies had shown that young mice with a global deletion of Eos did not appear to have defective Treg. To fully characterize the role of Eos in Treg function, we generated Eosfl/flx Foxp3Cre (Eos cKO) mice. Beginning at 3–4 months of age, both CD4+ and CD8+ T cells, as well as Treg in the Eos cKO mice expressed an activated/memory phenotype. The percentage of Tregs in the Eos cKO mice was higher than controls, suggesting that the Eos deficient Tregs were attempting to inhibit the activated immune response. H&E staining revealed severe lymphoid infiltration of lungs, kidneys, liver, small intestine, salivary glands of Eos cKO mice. The autoimmune state in the Eos cKO mice was characterized by enhanced levels of IFN-g production by CD4+ Foxp3− T cells, elevated percentages of T-follicular helper cells, and elevated levels of serum anti-nuclear antibodies. Tregs from Eos cKO mice failed to protect in the IBD transfer model and cKO mice also demonstrated enhanced susceptibility to EAE. Nevertheless, the in vitro suppressive function of Treg from cKO was normal. We determined the phenotype of Eos deficient Tregs under non-inflammatory conditions in heterozygous Eosfl/fl Foxp3cre/+ female mice. Although the thymic development of Eos deficient Tregs was not impaired, a marked reduction in Eos deficient Tregs was present in secondary lymphoid tissues indicating a defect in Treg survival in a competitive environment. We conclude that Eos is not required for the development of Tregs, but plays a critical role in controlling many, but not all, of the suppressive functions of Treg.
Activation induced decrease and recovery of TCR 2D affinity and bond lifetime
Authors: Andargachew Rakieb , Kolawole Elizabeth Motunrayo , Evavold Brian D. 
Published: January 2023

Abstract
Shortly after encountering antigen, T cells are considered transiently unresponsive or refractory to subsequent simulation. To determine whether antigen stimulation also changes the cell surface biophysical interaction between TCR and pMHC, we assessed the 2D TCR affinity and bond lifetime under force between this receptor ligand pair. Virus (LCMV) specific SMARTA transgenic CD4+ T cells were stimulated with peptide in vitro and 2D TCR affinity and bond lifetime determined at various time points after stimulation using the 2D micropipette adhesion frequency assay and the biomembrane force probe (BFP) respectively. We found activated T cells downregulated 2D affinity at twelve and twenty-four hours after seeing antigen with affinity recovering to naïve levels by forty-eight hours. Unlike pMHC tetramer staining which was dependent on TCR expression levels, the decrease in affinity was independent of antigen dose and degree of TCR downregulation. TCR:pMHC bond lifetime under force was also reduced early after antigen encounter with a steady recovery observed with time. Our data demonstrate a decrease in bond lifetime and relative 2D affinity of TCR and pMHC result from early T cell activation events followed by a recovery phase with both changes occurring independent of activation induced modulation of TCR expression. Thus, TCR affinity for pMHC is dynamic in the 2D T cell membrane context with cellular events allowing the T cell to fine-tune the ability of TCR to interact with antigen.
Tetrandrine (TET) up-regulated mTNF expression on dendritic cells and consequently induces TNFR2 mediated proliferation of Tregs
Authors: He Tianzhen , Yang De , Chen Xin , Oppenheim Joost J. 
Published: January 2023

Abstract
Tetrandrine (TET) is a purified chemical compound with well-established anti-inflammatory and immunosuppressive properties. The underlying mechanism of its immunosuppressive effect remains incompletely understood. It is also reported that membrane-bound (mTNF) is more effective than soluble TNF to expand Tregs through TNFR2. Therefore, we examined the effect of TET on TNF expression on dendritic cells (DCs) and its effect on Tregs in wildtype and TNFR2 KO mice. We found that, TET didn’t directly expand Tregs in vitro. But TET increased mTNF expression on DC2.4 cells and human monocyte-derived DCs. In addition, these effects of TET weren’t due to LPS contamination. Intraperitoneal injection of TET into wildtype mice increased the number of Tregs by ~1.5-fold compared with control mice. TNFR2 expression was up-regulated on Tregs rather than Teffs by TET treatment. However, the number of Tregs wasn’t changed by TET in TNFR2 KO mice. Taken together, our study revealed that TET promoted mTNF expression on DCs and consequently expanded Tregs via mTNF-TNFR2 signaling. Therefore, this represents a novel mechanism underlying the anti-inflammatory effect of TET.
Chaperone mediated autophagy and T cell function
Authors: Reynolds Cara A. , Macian Fernando 
Published: January 2023

Abstract
Autophagy is a cellular quality control mechanism that degrades and recycles cellular components in the lysosome to maintain cellular homeostasis and to regulates protein levels in response to stimuli. Chaperone mediated autophagy (CMA) is a selective form of autophagy that targets soluble cytoplasmic proteins for degradation. In CMA, the chaperone Hsc70 recognizes and binds a CMA-targeting motif in the substrate and brings it to the LAMP-2A receptor on the lysosomal membrane. The receptor multimerizes and the substrate translocates into the lysosome to be degraded. We have previously reported that CMA is upregulated in activated CD4+ T cells, where it is required to support proliferation and cytokine production. However, the signaling pathways that regulate CMA activity during the immune response and cell type-specific functions of CMA are not fully characterized.
We have found that retinoic acid receptor alpha (RARα) signaling inhibits CMA, and that modulation of RARα signaling with chemically modified retinoic acid derivatives leads to CMA activation. We have used these novel CMA activators to identify target genes involved in the regulation of CMA in T cells. Furthermore, our data supports that LAMP-2A expression and CMA activity are down-regulated in aged T cells, which correlates with the age-associated decreases in T cell function. Interestingly, genetic restoration of LAMP-2A expression in aged cells enhances T cell responses. Therefore, we have explored how CMA activating compounds may restore CMA activity in aged T cells boosting T cell function.
Uracil DNA Glycosylase of Gammaherpesvirus alters somatic hypermutation through error-free DNA repair
Authors: Mu Yunxiang , Dong Qiwen , Zelazowska Monika Anna , Chen Zaowen , Plummer Joshua , Krug Laurie , McBride Kevin M. 
Published: January 2023

Abstract
The gammaherpesviruses (gHV) which include human Epstein Barr virus (EBV), Kaposi’s sarcoma-associated herpesvirus (KSHV) and murine gammaherpesvirus 68 (MHV68) are associated with B cell malignancy including Burkitt lymphoma. All herpesvirus encode a viral homolog of the mammalian Uracil DNA-glycosylase (UNG) gene. In B cells, mammalian UNG plays a critical role in the antibody diversification processes of class switch recombination (CSR) and somatic hypermutation (SHM). UNG processes U:G mismatches created by activation-induced cytidine deaminase (AID) in an error-prone fashion to accomplish CSR and SHM. During primary infection, gHV expands in the germinal center B cells which actively express AID and undergo CSR and SHM. However, the function of viral UNG (vUNG) on viral pathogenesis and host genome integrity during the mutagenic germinal center reaction is an open question. Using a MHV68 mouse infection model we find that germinal center cells are the major viral targets during acute infection. Analysis of infected cells demonstrates significant overlap of vUNG and AID expression. Using a cell based hypermutation reporter assay, we find that host UNG supports error-prone repair and mutagenesis while vUNG results in only high-fidelity error-free repair of AID lesions. In vitro biochemical characterization finds several differences between vUNG and host UNG, including the ability of vUNG to bind abasic sites. These results demonstrate a differential ability of UNGs to support error-prone versus error-free repair. The finding that vUNG is expressed in germinal center cells suggest a novel mechanism whereby gammaherpesvirus can affect antibody diversification and B lymphocyte function.
Role of E3 ubiquitin ligase GRAIL in B cell activation and tolerance
Authors: Nurieva Roza I. , Bieerkehazhi Shayahati , Waseem Tayab C. , Hoang Oanh N. , Sahoo Anupama , Alekseev Andrei , Galkina Elena 
Published: January 2023

Abstract
To date, B cells are believed to play a central role in pathogenesis of various autoimmune diseases as loss of B-cell tolerance with emergence of autoreactive B cells and pathogenic autoantibodies are the hallmark features of autoimmune disorders; however the intrinsic mechanisms that underlie initial breaks in B cell tolerance have not been completely defined. GRAIL, gene related to anergy in lymphocytes (encoded by Rnf128) is an E3 ubiquitin ligase associated with CD4+ and CD8+ T cell tolerance. Our data for first time show GRAIL expression in both mouse and human B cells, with higher expression in anergic B cells and that GRAIL deficiency in B cells leads to impaired B cell peripheral tolerance induction and greater susceptibility to autoimmune diseases. GRAIL deficient B cells exhibited hyperresponsivness in terms of proliferation and antibody production upon antigen stimulation in vitro and in vivo. Concomitantly, GRAIL-deficient B cells were less efficient in downregulation of IgM after B cell receptor (BCR) crosslinking and exhibited increased CD79a expression and activation leading to elevated activation of proximal BCR-signaling components and Ca2+mobilization; GRAIL expression promoted CD79a ubiquitination and degradation. Interestingly, GRAIL expression is also essential to control antigen-presenting property of B cells towards T helper 1 (Th1), Th2, Th17 and follicular helper T (Tfh) cells; since GRAIL deficiency in B cells leads to augmented development and function of Th1, Th2, Th17 and Tfh cells in vitro and in vivo. Thus, our results indicate that GRAIL is a crucial intrinsic factor controlling B cell activation and tolerance by targeting of BCR component CD79a for degradation.
Macrophages and the regulation of pulmonary fibrosis by Cadherin-11
Authors: To Sarah , Agarwal Sandeep K. 
Published: January 2023

Abstract
Pulmonary fibrosis is a chronic lung disease characterized by excessive deposition of extracellular matrix proteins by myofibroblasts leading to remodeling of the lung architecture. Alveolar macrophages play a key role in the development of pulmonary fibrosis and it has generally been associated with the polarization of these cells towards a profibrotic phenotype. Studies have shown the expression of the cell adhesion molecule Cadherin-11 (Cdh11) in alveolar macrophages from patients with pulmonary fibrosis and mice given bleomycin, and Cdh11-deficient mice are protected from bleomycin-induced pulmonary fibrosis suggesting an important role for Cdh11 in the pathogenesis of pulmonary fibrosis. In order to understand the role of Cdh11 in the development of pulmonary fibrosis, our study focuses on macrophages and aims to characterize the function and phenotype of Cdh11-deficient macrophages. We show that Cdh11-deficient mice have reduced numbers of tissue-resident alveolar macrophages compared to the wild type control mice and when given bleomycin, these mice have reduced numbers of CD11b+ monocyte-derived alveolar macrophages. Using BMDMs derived from Cdh11-deficient mice, we show that Cdh11-deficient macrophages have decreased expression of the alternative activation markers Arg1, Ym1, and CD206, and reduced secretion of TGF-β1, suggesting a reduced fibrotic phenotype. Furthermore, we show decreased phagocytosis, proliferation, and migration by Cdh11-deficient macrophages. These data suggest that Cdh11 may alter fibrotic responses by regulating the number and function of alveolar macrophages that are recruited to the lung.
Role of the KLRG1 pathway in the immune response
Authors: Tata Angela , Brossay Laurent 
Published: January 2023

Abstract
Killer cell lectin-like receptor G1 (KLRG1) is a C-type lectin inhibitory receptor that contains an immunoreceptor tyrosine-based inhibitory motif (ITIM) in its cytoplasmic domain. KLRG1 is well conserved in mammals and is mostly expressed on subsets of T cells and natural killer (NK) cells. Upon binding to its ligands, N-cadherin and E-cadherin, the phosphatases SHP-2 and SHIP-1 are recruited to the cytoplasmic tail of KLRG1. Some studies have proposed that KLRG1 is a marker of senescence, while other studies suggest that KLRG1 is a marker of recently activated cells. In addition, although KLRG1 inhibitory potential has been established in vitro, it is unclear whether KLRG1 inhibits NK cells and CD8+ T cells in vivo. To address its exact role, we have used CRISPR technology to generate mice deficient for KLRG1 and mice conditionally deficient for KLRG1 in the NK cell lineage. We found that NK cell frequency and number is not effected and that NK cell development is globally intact in KLRG1 deficient mice. The role of KLRG1 during viral infections and tumor development is currently being investigated.
Prostaglandin E2 threshold dictates susceptibility to skin infection in diabetic mice
Authors: Klopfenstein Nathan , Brandt Stephanie , Judge Allison , Serezani Carlos Henrique 
Published: January 2023

Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is the primary cause of skin infection in people with diabetes. MRSA skin infection is characterized by the migration of phagocytes and abscess formation to prevent deeper tissue infections. However, the events that drive poor host defense in diabetes is poorly understood. Here, we examined the role of the lipid mediator prostaglandin E2 (PGE2) and its impact on host defense during MRSA skin infection in diabetes. We have shown that diabetic mice are unable to control MRSA skin infection, along with excessive cytokine production and neutrophil migration. Our data indicate that PGE2 production is lower in diabetic mice than nondiabetic mice at both days 1 and 9. Daily topical treatment with a PGE2 analog decreased lesion size and improved bacterial clearance in the skin of infected diabetic mice. Reduced lesion size in PGE2-treated diabetic mice correlated with decreased production of the cytokines TNF-, IL-1, and IL-6 and neutrophil migration. While we did observe a well-defined abscess in infected nondiabetic mice, infection in diabetic mice resulted in poor abscess formation; and topical PGE2 treatment restores abscess formation. Poor skin defense in diabetic mice also correlated with increased numbers of dead cells at days 1 and 9 post-infection suggesting that dead cells are not eliminated. When we studied the expression of molecules involved in dead cell ingestion, we observed an increased abundance of inhibitory receptor SIRPa in infected diabetic mice and PGE2 ointment restored SIRPa levels back to those observed in infected nondiabetic mice. These data indicate that the threshold of PGE2 drives the inflammatory milieu during infection and effects skin homeostasis in diabetes.
Defect in neutrophil function accounts for impaired anti-fungal immunity in kidney dysfunction
Authors: Jawale Chetan , Ramani Kritika , Biswas Partha Sarathi 
Published: January 2023

Abstract
Chronic kidney disease is increasingly recognized as a major public health problem, and has a prevalence of 10% in the general population. Accumulation of uremic toxins results in systemic immunosuppression. Sepsis due to microbial infections accounts for 20% of deaths in patients with kidney diseases. Increased susceptibility of uremic patients to invasive fungal infections may attribute to impairment of innate immune defense. However, the molecular mechanisms of impaired anti-fungal immunity in kidney dysfunction are poorly understood. In this study, we have used the mouse model of aristolochic acid nephropathy to investigate the effect of uremia on antifungal immunity. A single IP injection of aristolochic acid I resulted in severe tubulointerstitial injuries accompanied by increased level blood urea nitrogen. Uremic mice showed increased Candida albicans burden in the internal organs following systemic infection. Increased fungal load was not attributed to defect in migration of neutrophils in the infected organs. Uremic condition impaired the ROS production and fungicidal activity of neutrophils. Interestingly, incubation of neutrophils with uremic serum led to impairment of their energy metabolism, indicated by reduced ATP content and lactate production. Neutrophils incubated with uremic serum showed reduced Glut1 protein expression and impaired glucose uptake capacity. Surprisingly, uremic serum inhibited PI3K/AKT pathway leading to aberrant activation of GSK3β in neutrophils. Furthermore, inhibition of GSK3β restored the glucose uptake in neutrophils incubated with uremic serum. These results indicate that uremia suppresses the anti-fungal activity of neutrophils by inhibiting their immunometabolism.