bluuebunny/crossref_metadata_2025_split huggingface dataset:
The gene related to anergy in lymphocytes regulates stat-mediated differentiation of CD4 T cells via ubiquitination and degradation of the kinase chaperone CDC37 (P1128)
Authors: Schartner Jill , Su Leon , Fathman C. Garrison , Whiting Chan 
Published: January 2023

Abstract
GRAIL, an E3 ligase, is necessary and sufficient for the induction of T cell anergy. GRAIL expression is rapidly diminished following T cell activation. Recent data demonstrated naïve CD4+ T cells from GRAIL KO mice are more efficient than WT T cells in skewing toward a Th1 or Th17 phenotype. The molecular basis by which GRAIL regulates T cell differentiation is not known. Using microarray analysis of naïve CD4 T cells we identified dysregulated signaling pathways in GRAIL KO cells. Ingenuity Pathway Analysis of dysregulated genes in GRAIL KO CD4 T cells revealed activation of multiple pathways downstream of STAT. We found that naïve CD4 T cells from KO mice hyper-phosphorylated Stat3 and 5 in response to stimulation with IL-6 and IL-2 respectively. To identify GRAIL substrates that contribute to the hyperSTAT status in KO T cells, we used a bacterial genetic screen to identify CDC37 as a target for ubiquitination and degradation by GRAIL. CDC37/Hsp90 serve as co-chaperones that stabilize expression of kinases including Jak1/2, key regulators of STATs in cytokine signaling. Loss of GRAIL may result in increased CDC37-mediated enhancement of Jak1/2 activity allowing more efficient cytokine signaling. Conversely, increased GRAIL expression in anergic and regulatory T cells may limit cytokine signaling. These data suggest a role for GRAIL in regulating global response to cytokine and is the first report on the role of an E3 ligase in modulating T cell differentiation.
Rapid recall ability of memory T cells is associated with epigenetic gene poising (P1134)
Authors: Barski Artem , Cuddapah Suresh , Kartashov Andrey , Imamichi Hiromi , Lane Clifford , Zhao Keji 
Published: January 2023

Abstract
While association of histone modifications with expressed or silent genes has been established, it remains unclear how changes in chromatin environment relate to changes in gene expression. We used ChIP-Seq to analyze the genome-wide changes in chromatin modifications during short-term activation of total human CD4+ T cells by T cell receptor (TCR) signaling. In resting and activated T cells, expressed genes were strongly associated with “active” modifications (e.g. H3K4me1/2/3, H2A.Z) and RNA Polymerase II (Pol II), while silent genes were typically associated with repressive marks. However, we found that about 20-30% of silent genes were poised - they possessed positive modifications and sometimes even Pol II at their promoters. Interestingly, majority of genes induced during T cell activation were poised in resting cells even before the TCR signaling was initiated. Similarly, genes that were silenced upon T cell activation retained active chromatin modifications even after being silenced. This suggested that poising might result from memory of past transcription. We next proceeded to compare histone modification profiles of naïve and memory T cells and discovered that ability of memory cells to produce characteristic cytokines is correlated with the presence of poising marks at the enhancers and promoters of these genes. This led us to propose a model of T cell memory in which immunological memory state is determined epigenetically - by transcriptional memory and poising.
The role of TRAF3 in B cell specific regulation of survival and malignancy (P1112)
Authors: Lin Wai , Stunz Laura , LeBeau Robert , Mambetsariev Nurbek , Bishop Gail 
Published: January 2023

Abstract
TNF-receptor associated factor 3 (TRAF3), a negative regulator of CD40 and BAFF-receptor- mediated signaling pathways, also serves as a potentially important tumor suppressor in B cell malignancies. Deletion or loss of function mutations of the traf3 gene are highly associated with multiple myeloma (MM) and different subtypes of B cell lymphoma. Current dogma has attributed TRAF3’s role of restraining cell survival to its negative regulatory role in activating the non-canonical NF-κB2 pathway. However, studying cell-type-specific TRAF3-deficient mouse strains we produced, we found that TRAF3 deletion in B cells, T cells or dendritic cells all results in constitutive NF-κB2 activation, while enhanced cell survival is unique to TRAF3 deficient B cells. This indicates that TRAF3 must negatively regulate additional survival or anti-apoptotic pathways in a B-cell-specific manner. Our recent results show that TRAF3 deficient B cells, but not other TRAF3-deficient cell types, highly express the pro-survival kinase Pim2. Pim2 expression levels also correlate with copy number and loss of function mutations in the traf3 gene in human MM cell lines. TRAF3 deficient B cells also display higher basal levels of the activated form of the B cell-specific kinase Btk, a kinase implicated in MM pathogenesis. These findings reveal B cell-specific mechanisms by which TRAF3 can exert its cell-specific impact on regulation of survival, and are being further explored in ongoing work.
Kinase-independent feedback of the TAK1/TAB1 complex on BCL10 proteolysis and NF-κB activation in lymphocytes (P1114)
Authors: Moreno-Garcia Miguel , Sommer Karen , Rincon-Arano Hector , Brault Michelle , Ninomiya-Tsuji Jun , Matesic Lydia , Rawlings David 
Published: January 2023

Abstract
Somatic mutations resulting in constitutive activation of the CARMA1 scaffolding protein occur frequently in poor prognosis diffuse large B cell lymphoma (DLBCL). Such mutations directly promote assembly of the CARMA1, BCL10, MALT1 (CBM complex) thereby leading to activation of the IKK signalosome. These events lead to sustained NF-κB signaling, which is essential for lymphocyte survival. Thus, understanding the events that down-regulate CBM complex assembly is predicted to identify novel therapeutic targets in DLBCL. Notably, stimulation of antigen receptors simultaneously triggers both CARMA1-dependent BCL10 activation and CARMA-dependent-BCL10 degradation, which ultimately limits CARMA1 signaling. Using mutant B cell models, and genetic as well as biochemical approaches, we identify a kinase-independent requirement for the kinase, TAK1, and its adaptor, TAB1, in antigen receptor-induced BCL10 proteolysis. We show that TAK1 acts as an adaptor for E3 ubiquitin ligases that target BCL10 for degradation. Functionally, TAK1 over-expression restrains CARMA1-dependent NF-κB activation by reducing BCL10 levels. TAK1 also promotes counter-selection of NF-κB-addicted DLBCL lines by a dual mechanism involving kinase-independent degradation of BCL10 and kinase-dependent activation of JNK. Thus, by directly promoting BCL10 degradation, TAK1 counter-balances NF-κB and JNK signals essential for activation and survival of lymphocytes and CARMA1-addicted lymphoma types.
Phenotypic and functional analysis of double negative T cells in kidney. (P1002)
Authors: Martina Maria , Dai Hong , Uddin Sophia , Bandapalle Samatha , Chiu Yen-Ling , Rabb Hamid , Hamad Abdel 
Published: January 2023

Abstract
Double negative T cells (DNT cells) are the main subset in kidney lymphocytes. In peripheral blood represent less than a 5%, but they gradually accumulate in lymph nodes and spleens of deficient FasL mice (gld). The role of these cells in kidney and how they mediate suppression/regulation are unknown. We performed a comprehensive phenotypic and functional analysis of this population in kidney. Hypothesis: DNT cells modulate immune responses in kidney. They have a suppressive function on cytokine production, playing a role in protection cells from injury. Methods: Purified T lymphocytes from mice were analyzed for expressing surface markers and cytokines secretion. B6 wild type, gld mice and ischemic reperfusion injury mice model were used. Surface and intracellular staining were done and analyzed with flow cytometry. Results: There are more DNT cells in the kidney (B6 and gld) than renal draining lymph nodes or inguinal lymph nodes. The percentage decreases in kidney after reperfusion ischemic injury. DNT cells showed an increased expression of activation markers such as CD44/CD69/CD28 compared to CD4+ and CD8+ in kidney. DNT cells exhibit a low secretion of cytokine like IL-17, IL4 or IFN gamma. Conclusion: Our data shows that double negative T cells have the potential to modulate immune responses in kidney. This is promising for better control of kidney injury or autoimmunodiseases.
T lymphocyte responses to RBC-derived microparticles are APC-dependent (P1040)
Authors: Danesh Ali , Inglis Heather , Heitman John , Norris Philip 
Published: January 2023

Abstract
Microparticles (MPs) generated in stored blood are thought to cause immunomodulatory effects in blood recipients. MPs are small double membrane vesicles derived from leukocytes, platelets or other cells. We hypothesized that RBC-derived MPs would inhibit T cell responses. MPs were isolated from stored RBCs using differential centrifugation. PBMCs were cultured +/-MPs, supernatants were collected on day one, and PBMC survival was tested on day seven. PBMCs or purified T cells were stained with CFSE and cultured for seven days with PHA+/-MP. We found that MPs alone induced pro-inflammatory cytokine secretion and enhanced survival of T cells, B cells, and NK cells to a similar degree, but did not induce T cell proliferation. MPs augmented PHA-induced proliferation of CD4+ and CD8+ T cells in PBMC cultures, and blockade of CD40 or CD40L accessory molecules prevented the augmentation effect of MPs on T cell proliferation. Furthermore, stimulation of purified T cells with PHA+/-MP did not induce T cell proliferation, and addition of MP-exposed and washed monocytes to purified T cells recapitulated augmentation of T cell proliferation. In summary, addition of RBC-MPs to PBMCs improved survival of unstimulated cells and augmented mitogen driven T cell responses in an APC-dependent manner. These results suggest that, contrary to our hypothesis, MPs found in transfusion products may bias the recipient immune system in a pro-inflammatory fashion.
Different Munc13 isoforms function as priming factors in lytic granule release from murine cytotoxic T lymphocytes (P1044)
Authors: Krause Elmar , Dudenhöffer-Pfeifer Monika , Schirra Claudia , Marshall Misty , Halimani Mahantappa , Ulf Matti , Pattu Varsha , Becherer Ute , Dirks Jan , Jung Martin , Lipp Peter , Hoth Markus , Sester Martina , Rettig Jens 
Published: January 2023

Abstract
In order to fuse lytic granules (LGs) with the plasma membrane at the immunological synapse, cytotoxic T lymphocytes (CTLs) have to render these LGs fusion-competent through the priming process. In secretory tissues like brain and neuroendocrine glands this process is mediated by members of the Munc13 protein family. In human CTLs mutations in the Munc13-4 gene cause a severe loss in killing efficiency, resulting in familial hemophagocytic lymphohistiocytosis type 3 (FHL3) suggesting a similar role of other Munc13 isoforms in the immune system. Here, we investigate the contribution of different Munc13 isoforms to the priming process of murine CTLs. We demonstrate on both mRNA and protein level that Munc13-1 and Munc13-4 are the only Munc13 isoforms present in mouse CTLs. Both isoforms rescue the drastical secretion defect of CTLs derived from Munc13-4-deficient Jinx mice. Furthermore mobility studies of LGs performed with TIRF micrscopy indicate that Munc13-4 as well as Munc13-1 are responsible for the priming process of LGs. Even more the domains of the Munc13 protein which are responsible for functional fusion could be identified. We conclude from these data that both isoforms of the Munc13 family are functionally redundant and identify Munc13-1 as an alternative target for immunotherapy in patients suffering from FHL3.
Stunned invariant NKT cells are not anergic, but acquire IL-10-dependent regulatory characteristics (P1052)
Authors: Wingender Gerhard , Sag Duygu , Krause Petra , Tyznik Aaron , Hedrick Catherine , Kronenberg Mitchell 
Published: January 2023

Abstract
Invariant NKT (iNKT) cells are a unique subset of T lymphocytes that after activation produce copious amounts of cytokines, impacting a dazzling variety of different immune reactions. However, it has been reported that strong activation of iNKT cells with the synthetic model antigen α-galactosylceramide (αGalCer) induces a hypo-reactivity that was proposed to be related to anergy. In contrast, here we report, that αGalCer pretreated iNKT cells, referred to here as ‘induced stunned’ iNKT (isNKT) cells, retain their cytotoxic activity and their response to TCR-independent, cytokine-mediated stimulation. Additionally, isNKT cells acquire characteristics of regulatory cells, marked by the expression of PD-1, Neuropilin-1, CD152 and the ability to produce IL-10. Through the production of IL-10, isNKT cells were able to modulate the tumor load of mice challenged with B16 melanoma and to ameliorate the outcome of Experimental Autoimmune Encephalomyelitis (EAE). Furthermore, a subset of iNKT cells with a stunned phenotype and function were present even in untreated mice, and were enriched in adipose tissue, indicating that natural stunned iNKT cells are present in vivo under steady state conditions. Preliminary data suggest that such stunned iNKT cells can also be found in human PBMCs. These data demonstrate that stunned iNKT cells are not anergic but rather acquire a novel functional state with regulatory potential and that they likely represent a novel, distinct iNKT cell subset.
Sprouty-2 and the MAPK/ERK pathway regulate polyfunctionality of virus-specific human T cells (P1006)
Authors: Chiu Yen-Ling , Haupt Carl , Oelke Mathias , Powell Jonathan , Griffin Diane , Schneck Joanthan 
Published: January 2023

Abstract
The ability for a single T cell to upregulate multiple effector functions, polyfunctionality, is crucial for protective immunity. Loss of polyfunctional T cells during chronic viral infections is associated with pathogen persistence and results in poor memory T cell formation and progressive T cell exhaustion. However, the molecular mechanisms determining the generation and maintenance of polyfunctional T cells remain unclear. We found that CD8+ T cell polyfunctionality can be directly regulated by antigen dose. High antigen dose stimulation induced robust T cell proliferation but, in contrast, only poorly polyfunctional T cells. Microarray analysis revealed that poorly polyfunctional T cells induced by high dose antigen had a unique transcription profile similar to exhausted T cells observed during chronic viral infections including upregulation of inhibitory receptors. However, the poorly polyfunctional T cell state was independent of inhibitory receptor signaling. Instead, biochemical and genetic experiments showed that the inhibition of MAPK/ERK pathway through upregulation of spry2, a negative regulator of the MAPK/ERK pathway, directly modulated polyfunctionality by selectively inhibiting cytokine secretion. Our findings reveal novel mechanisms controlling human T cell polyfunctionality and are directly relevant to effective vaccine development and T cell immunotherapy.
Opposing roles of PD-1 and PD-L in modulating CNS inflammation and infarct volume following experimental stroke in mice (P1012)
Authors: Bodhankar Sheetal , Chen Yingxin , Murphy Stephanie , Offner Halina 
Published: January 2023

Abstract
Stroke severity is worsened by recruitment of inflammatory immune cells into the brain. This process depends in part on T cell activation, in which the B7 family of co-stimulatory molecules plays a pivotal role. Previous studies demonstrated more severe infarcts in mice lacking Programmed Death-1 (PD-1), a member of the B7 family, thus implicating PD-1 as a key factor in limiting stroke severity. The purpose of this study was to determine if this protective effect of PD-1 involves either of its ligands, PD-L1 and PD-L2. Thus, CNS inflammation and stroke severity were evaluated in male PD-L1 and PD-L2 knockout (KO) mice undergoing 60 min middle cerebral artery occlusion (MCAO) followed by 96 h reperfusion. Unexpectedly, PD-L1 KO and to a lesser extent PD-L2 KO mice had reduced levels of activated microglia and infiltrating monocytes and total infarct volume compared to wild-type mice, as well as reduced splenic atrophy and MHC class II expression, suggesting a pathogenic rather than a regulatory role for both PD-ligands. Both positive and negative regulatory roles have been suggested for the PD-ligands in context of various diseases and our novel observations indicate that PD-L1 and PD-L2 might have proinflammatory functions independent of PD-1 binding that worsen stroke outcome. These results suggest the possibility of using antibodies to PD-L1/2 as a potential treatment for human stroke patients.
mCMV alters the airway inflammatory milieu regulating protective and pathogenic heterologous immunity to influenza A virus infection (P6137)
Authors: Sharma Shalini , Duan Susu , Thomas Paul 
Published: January 2023

Abstract
Prior immunity to apparently unrelated pathogens can affect the course of subsequent acute infections. The mechanisms of heterologous regulation in most circumstances remain poorly defined. In mice co-infected with murine cytomegalovirus (mCMV) and Influenza A virus (IAV), we show that prior infection with mCMV results in significantly reduced weight loss upon acute challenge with IAV as well as improved recall responses. Tetramer and ex-vivo ICCS assay showed an early recruitment of mCMV specific CD44hi CD62Llo IFNγ+ TNFα+ CD8 T cells in the bronchoalveolar lavage (BAL) of both acutely and latently infected animals following IAVx31 challenge that was absent in mice infected with CMV-alone. This protection was dependent on IFNγ production by these mature anti-CMV CD8 T cells, the protective phenotype was completely ablated in co-infected IFNγ-/- animals or in animals co-infected simultaneously. However, no cross-reactive T cells were detectible. Furthermore, comparative kinetics of CMV specific CD8 T cell responses showed that IAV infection resulted in the attrition of the CMV specific CD8 T cell response in both acutely and latently infected animals. Finally, analysis of the IAV-specific T cell receptor repertoire by multiplex nested PCR suggested that prior CMV infection altered the recruited IAV-specific T cell repertoire. These data demonstrate that CMV co-infection can determine the outcome of subsequent IAV infection by altering the airway microenvironment.
The PB1-F2 protein of influenza A virus induces danger molecule accumulation in infected lungs, priming for an enhanced inflammatory response to bacterial pneumonia (P6162)
Authors: Brown Nicholas , Zheng Pan , Liu Yang 
Published: January 2023

Abstract
We recently described a signaling pathway, CD24-Siglecg G/10, that suppresses the inflammatory response to danger-associated molecular patterns (DAMPs). Here we report on the role of DAMPs in secondary bacterial pneumonia following influenza A virus (IAV) infection. During IAV infection, two prototypical DAMPs, HSP70 and HMGB1, accumulated in the lungs of infected mice. IAV PB1-F2, a protein encoded by highly-pathogenic strains, such as 1918 “Spanish flu,” contributed to this accumulation, as infection with PB1-F2-deficient IAV led to a decrease in DAMPs. To model bacterial superinfection, we administered sublethal LPS intranasally 7 days after IAV infection. While all mice were more sensitive to the LPS challenge after IAV infection, CD24-/- and siglecg-/- mice did not recover from LPS challenge as quickly as WT mice. Indeed, this regimen was lethal for a subset of knockout mice, while all WT mice survived. Furthermore, CD24- and Siglec G-deficient mice were more susceptible to superinfection with the gram-negative bacterium Haemophilus influenzae. Together these results demonstrate that the ability of inflammatory PB1-F2 protein of IAV to prime for lethal, secondary bacterial pneumonia is due to the accumulation of DAMPs in the lungs of infected animals, and provide new targets for the treatment of this often fatal disease.
Partial MHC class II constructs inhibit MIF/CD74 binding and downstream effects (P5221)
Authors: Benedek Gil , Meza-Romero Roberto , Andrew Shayne , Leng Lin , Burrows Gregory , Bourdette Dennis , Offner Halina , Bucala Richard , Vandenbark Arthur 
Published: January 2023

Abstract
Macrophage migration inhibitory factor (MIF) and its receptor, CD74, are pivotal regulators of the immune system. Here we demonstrate for the first time that partial MHC class II constructs comprised of linked beta 1 alpha 1 domains with covalently attached antigenic peptides (also referred to as recombinant T cell receptor ligands - RTL) can inhibit MIF activity by not only blocking the binding of rhMIF to immunopurified CD74, but also down-regulating CD74 cell-surface expression. This bi-functional inhibition of MIF/CD74 interactions blocks downstream MIF effects, including enhanced secretion of proinflammatory cytokines, anti-apoptotic activity and inhibition of random migration that all contribute to reversal of clinical and histological signs of experimental autoimmune encephalomyelitis (EAE). Moreover, we demonstrate that enhanced CD74 cell surface expression on monocytes in mice with EAE and subjects with multiple sclerosis (MS) can be down-regulated by humanized RTL, resulting in reduced MIF binding to the cells. Thus, binding of partial MHC complexes to CD74 blocks both the accessibility and availability of CD74 for MIF binding and downstream inflammatory activity.
Activation of monocytes and dendritic cells through TLR4: modulation by dendrimer ABP as a potential therapeutic agent. (P5226)
Authors: Davignon Jean-Luc , Degboé Yannick , Fruchon Severine , Turrin Cédric-Olivier , Caminade Anne-Marie , Poupot Rémy , Cantagrel Alain 
Published: January 2023

Abstract
Rheumatoid Arthritis (RA) is a chronic inflammatory autoimmune disease whose etiology is unknown. Monocytes (Mo) and dendritic cells (DC) are major mediators of inflammation and immune regulation. We have previously shown that aza-bisphosphonate (ABP) dendrimer targets Mo and reduces inflammation and bone erosion in mouse arthritis. However, the potential effect of ABP on inflammatory human Mo and DC is not well understood. We have used ABP to treat human Mo and DC that were stimulated in vitro with the TLR4 agonist LPS and with IFN-γ. Mo were purified from PBMC collected from healthy blood donors. DC were obtained by 6-day culture of purified Mo in the presence of GM-CSF and IL-4. Mo and DC were then preincubated alone or with 10µM ABP dendrimer for 1h, followed by LPS and IFN-γ. We quantitated the production of pro-inflammatory cytokines and IL-10, as well as markers of DC activation and maturation. ABP significantly decreased the production of TNF-α, IL-12 and IL-23. Furthermore, treated DC exhibited a tolerogenic profile, as suggested by an increase in IL-10, decrease in IL-12, and inhibition of maturation as assessed by inhibition of the costimulatory molecules CD80 and CD86 and of CD83. Our data extend our previous observations on the anti-inflammatory properties of ABP on human Mo and demonstrate the induction of a tolerogenic profile on DC. These observations should elucidate the in vivo response of the monocytic lineage to ABP as a novel compound for arthritis.