bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of Foxp3 in Treg homeostatic proliferation: Necessary for nTregs, but insufficient for iTregs. (LYM3P.734)
Authors: Lin Yan , Rothstein David 
Published: January 2023

Abstract
NTregs exhibit higher homeostatic proliferation (HP) than Tconv which may provide a competitive advantage during Treg adoptive immunotherapy. Increased Treg HP could be 2° to a self-reactive TCR repertoire and/or Foxp3-mediated increase in survival/fitness. To address this, CFSE-labeled CD4 populations from Foxp3-reporter mice, were compared 10d after transfer into wt mice. We generated Foxp3+ iTregs by activating Tconv and adding TGFβ, or transducing with Foxp3-retrovirus (RV). iTregs did not increase HP over Tconv controls (no TGFβ; RV-vector). Thus, Foxp3 itself is not sufficient to augment HP. To determine the role of Foxp3, we examined GFP+ nTreg from Filig mice (F-nTreg; Foxp3 ~10% wt levels due to unstable mRNA). F-nTreg exhibited reduced HP (10%) vs. wt nTregs (50%). Foxp3-RV transduction increased HP of F-nTregs, while RV-control had no effect (40 vs. 12%). Thus, Foxp3 is necessary for high HP by nTreg. We also examined role of Foxp3 during thymic ontogeny, irradiated Thy1.1 hosts received Filig (Thy1.2) bone marrow that was transduced with Foxp3-RV vs. RV-control. Surprisingly, in this setting, Tconv cells (no endogenous Foxp3) constitutively expressing Foxp3, exhibited increased HP vs. Foxp3- RV-controls (32 vs. 12%). Thus, Foxp3 increases HP in nTreg and when expressed during thymic ontogeny but not in mature Tconv. Our findings provide new insight into the role of Foxp3 expression in Treg homeostasis and highlight additional distinctions between iTreg and nTreg.
Signals through GITR program CD4+ T cells to enhance interleukin-9 production, which mediates antitumor CTL responses (LYM3P.735)
Authors: Kim Il-Kyu , Kim Byung-Seok , Seok Jae-Won , Koh Choong-Hyun , Park Jun-Seok , Shin Kwang-Soo , Lee Ga-Eun , Jeon Hyewon , Chung Yeonseok , Kang Chang-Yuil 
Published: January 2023

Abstract
IL-9-producing T helper cells called Th9 have been a recently identified Th subset diverted from Th2 cells and proved to mediate allergic inflammation and tumor immunity. However, the regulation of Th9 development and functions in diseases remain to be elucidated. Here, we showed that GITR costimulation could induce tumor regression by promoting IL-9 expression on CD4+ T cells. GITR signaling intrinsically enhanced IL-9 expression regardless of cytokine milieu from CD4+ T cells, and furthermore in the presence of TGF-β, could induce IL-9-producing T cells independently of IL-4 in vitro. GITR activation increased the expression of Th9-related transcription factors, Irf4, Gata3 and Batf. In addtion, GITR activated the NF-κB signaling pathway and blockade of NF-κB signaling diminished the increase of IL-9 production from CD4+ T cells by GITR. In vivo GITR ligation augmented cytotoxic T cell responses in mouse tumor models and neutralization of IL-9 led to decrease the cytotoxicity of CD8+ T cells, resultingly impeded tumor regression by anti-GITR Ab. Upregulation of CTL responses was accompanied by the amplication through increasing the maturation and cross-presentaion of infiltrating DCs, regulated by IL-9. Thus, our studies reveal the link between GITR signaling and IL-9, providing a rationale for GITR-induced antitumor immune responses.
BDNF integrates cognitive and physical resilience with immune function in successful aging (LYM4P.753)
Authors: Griffin Patricia , Mueller Robert , Dube John , Huysman Kristy , Michel Joshua , Studenski Stephanie , Vallejo Abbe 
Published: January 2023

Abstract
Successful aging has been defined as functional resilience in late life despite history of chronic disease and/or concurrent medical conditions. Old age therefore may not be synonymous with ill health. We reported that octo-/nonagenarians who are survivors of a long-term cohort of aging have a distinct T cell repertoire expressing diverse NK-related receptors (NKR). Frequency of these unusual T cells is correlated with unimpaired physical/cognitive function. To determine whether broader repertoire remodeling relates to general well being, we recruited a new cohort of community dwelling elders aged &gt;65 years. Results showed physical/cognitive ability is unrelated with systemic cytokines, but with high levels of NKR on both T and NK cells, and brain-derived neurotrophic factor (BDNF) in plasma. Bioassays showed NKR ligation is sufficient to induce T/NK cell activation, and an unexpected production of BDNF. BDNF in culture supernatants and plasma was biologically active as determined by measurable impact on autocrine T/NK cell activation, and on paracrine neurite sprouting and myotube function. Clearly, physical/cognitive resilience is linked to remodeling of the immune cell repertoire. T/NK-derived BDNF indicate unique communication circuit(s) of immune, physical, and cognitive function domains. Unraveling NKR-driven non-TCR centric immunopathway(s) will be key to the development of age-appropriate, group-targeted strategies to promote healthy longevity.
Regulation of c-Myc from costimulatory signals modulates the generation of memory T cells (LYM4P.757)
Authors: Song Jianxun , Haque Mohammad 
Published: January 2023

Abstract
Costimulatory signals are critical for developing high numbers of memory T cells, which can generate optimal secondary immune responses. However, the mechanisms that cosimulatory signals regulate the generation of memory T cells remain to be elucidated. Here we show that the transcriptional factor c-Myc is controlled by costimulatory molecules, including CD28 of the Ig superfamily and OX40 of the TNFR family. Expression of c-Myc in Cd28-/- or Ox40-/- CD8+ T cells partially reversed the defects in the generation of memory T cells to viral infection. c-Myc regulated expression of survivin that promoted the generation of virus-specific CD8+ memory T cells. Moreover, expression of survivin and bcl-xL in Cd28-/- or Ox40-/- CD8+ T cells fully reversed the defects in the generation of memory T cells to viral infection. These data identify c-Myc, together with Nfkb1, as regulators of the generation of memory T cells from costimulatory signals.
miR-155 regulates lymphocyte homeostasis in LAT mutant mice (LYM4P.749)
Authors: Sommers Connie , Rouquette-Jazdanian Alexandre , Li WenMei , Nguyen Phan , Kortum Robert , Samelson Lawrence 
Published: January 2023

Abstract
LAT Y136F mutant mice carry a tyrosine-to-phenylalanine mutation in the LAT adapter gene that leads to a lymphoproliferative disease (LPD) initiated by CD4+ helper T cells. In a screen to detect microRNAs (miRs) specifically regulated in LAT Y136F CD4+ T cells, we found that levels of miR-155 were higher in these T cells than in other proliferating CD4+ T cells from wild type C57BL/6 mice. In order to reveal a potential role of miR-155 in LAT Y136F LPD, we crossed LAT Y136F mice to miR-155-deficient mice yielding double mutant (DM) mice. This resulted in a delay and decreased severity of LPD in DM mice. DM CD4+ T cells showed equal or higher proliferation rates than CD4+ T cells from age-matched LAT Y136F mice, however levels of apoptosis in DM CD4+ T cells were higher. One direct target downregulated by miR-155 is the forkhead transcription factor FOXO3a. In DM T cells, increased expression of FOXO3a led to accumulation of the pro-apoptotic factor Bim and enhanced apoptosis. In addition, elevated Pak1 kinase activity in DM T cells led to activation of Jnk leading to phosphorylation of FOXO3a, FOXO3a nuclear translocation and increased FOXO3a activity. Consequently, direct and indirect effects of miR-155 on FOXO3a led to an increase in Bim-mediated apoptosis and decreased LPD in DM mice. Investigation of downstream targets of miR-155 has led to new information on signaling molecules that control LPD and lymphocyte homeostasis.
Mir-17∼92 promotes terminal differentiation of effector CD8 T cells by lowering TCR stimulation threshold (LYM4P.750)
Authors: Baumann Florian , Yuzefpolskiy Yevgeniy , Sarkar Surojit , Kalia Vandana 
Published: January 2023

Abstract
MicroRNAs are small RNAs (∼22 nucleotides) that regulate gene expression via post-transcriptional mechanisms, and are emerging as major players in immune cell development and function. Using dual strategy of conditional deletion or constitutive overexpression of miR-17∼92, we have recently shown that miR-17∼92 has a critical CD8 T cell-intrinsic role in driving terminal effector differentiation by promoting proliferation (Khan, et al., 2013, Blood). We hypothesized that miR-17∼92 increases the sensitivity of CD8 T cells to TCR stimulation, thus driving proliferation and terminal differentiation. Indeed, when we overexpressed miR-17∼92 in effector CD8 T cells, we observed heightened levels of proximal phosphorylation events downstream of TCR. While PTEN and PD-1 (negative regulators of T cell stimulation) were downregulated upon overexpression of miR-17∼92, dramatic potentiation of TCR signal transduction occurred as evidenced by 50-fold upregulation of ribosomal S6 Kinase activity compared to WT. Converse results were obtained when miR-17∼92 was deleted, and about 10-folds higher levels of peptide-MHC were needed to induce TCR signals to levels similar to WT. Consistent with these observations, under conditions of limiting TCR stimulation, in vivo expansion of virus-specific miR-17∼92-deleted CD8 T cells was also severely compromised. Our data, altogether present a novel role of miR-17∼92 in regulating TCR sensitivity during CD8 T cell activation and effector differentiation.
Production of IL-10 during a streptococcus pneumoniae infection prevents excessive inflammation in lungs (MPF1P.778)
Authors: Peñaloza Hernan , Nieto Pamela , Salazar Francisco , Kalergis Alexis , Bueno Susan 
Published: January 2023

Abstract
Streptococcus pneumoniae (S. pneumoniae) is a Gram positive bacterium able to colonize and translocate the respiratory epithelium causing local and systemic diseases. It is a major cause of death worldwide, and despite the efforts made to develop strategies to prevent pneumococcal diseases, none of them are completely efficient. For this reason, it is necessary to fully understand the immune response against S. pneumoniae, and to develop new strategies that improve the host resistance to infection. One of the key component in the immune response is the anti-inflammatory cytokine IL-10 that modulates the inflammatory response against several pathogens, avoiding the excessive damage produced by the host immune system. In this study we evaluated the importance of IL-10 in the modulation of the innate immune response using a model of pneumococcal pneumonia in wild type (wt) and IL-10-/- mice. Our results show that wt mice overexpress IL-10 after infection, while in the absence of this cytokine, IL10-/- mice show excessive lung inflammation, higher neutrophil recruitment but normal monocytes. As a result, IL-10-/- mice have reduced bacterial load in lungs and deeper organs as compared with Wt mice. Our results support the notion that the production of anti-inflammatory cytokines, such as IL-10, during S. pneumoniae infection is required to avoid excessive inflammation of lungs and improve survival, despite the bacterial clearance is less efficient in the presence of this cytokine.
The fraction of T. cruzi-antigen specific T cells in chronic chagasic patients detected by CD154 and membrane TNFα expression (MPF2P.802)
Authors: Ripoll Juan , Giraldo Nicolás , Bolaños Natalia , Cuellar Adriana , Roa Nubia , Rosas Fernando , Velasco Victor , Cucunubá Zulma , Puerta Concepción , González John 
Published: January 2023

Abstract
Background: Chagas disease is a chronic parasitic infection whose pathogenesis is related to parasite persistence and a dysfunctional cellular immune response. There is no method to determine the pool of antigen-specific T cells in Trypanosoma cruzi-infected patients. Thus, the goal of this work was to determine the fraction of antigen-specific T cells by measuring the expression of CD154 and membrane TNFα on the bulk of parasite-stimulated PBMCs. Methodology: Twenty-one chagasic patients (CP), 11 healthy controls (HC) and 5 non-chagasic individuals with chronic heart disease (NCC) were analyzed. PBMCs were incubated in the presence of anti-CD28, anti-CD49d, anti-TNFα and TACE inhibitor as follows: non stimulus, T. cruzi-lysate or SEB. Later, the samples were stained for CD3, CD4, CD8 and CD154 and analyzed by flow cytometry. Results: Symptomatic (3.07%, SD ±1.98) and asymptomatic CP (1.24 ±0.59) displayed higher frequencies of CD4+/CD154+ cells after incubation with T. cruzi-lysate in comparison with NCC (0.084 ±0.03) and HC (0.11 ±0.08) donors P&lt;0.0001. Likewise, the frequency of CD8+ cells expressing membrane TNFα with parasite stimulus was higher in symptomatic (3.76% ±1.43) and asymptomatic patients (2.22 ±0.53) compared with NCC (1.28 ±0.45) and HC (0.57 ±0.41) donors P&lt;0.0001. Conclusions: These results suggest that membrane TNFα and CD154 after stimulation with T. cruzi-lysate could be useful to determine the fraction of parasite-specific T cells.
Role of IL-17 in intestinal ischemia-reperfusion injury. (MUC2P.829)
Authors: Geha Mayya , Bosse Robin , Tsokos Maria , Tsokos George 
Published: January 2023

Abstract
Background: Ischemia-reperfusion injury (IRI) to the small intestine following clamping of the superior mesenteric artery (SMA) results in an intense local inflammatory response characterized by neutrophil infiltration and villous damage. IL-17A is a cytokine expressed by a variety of cells in response to inflammatory cytokines that are released following tissue injury and/or inflammation. IL-17A induces epithelial cells to secrete neutrophil chemoattractants, such as CXCL2. The cytokine IL-23, which can be produced by epithelial cells, plays an important role in IL-17A production. Objective: To test the hypothesis that IL-17A is critical for intestinal damage following IRI. Materials and Methods: IRI was induced in mice by SMA clamping. IL-17A deficient (Il17a-/-) and IL-23R deficient (Il23r-/-) mice. Intestinal injury was evaluated by Chiu scores of jejunal histological sections. Results: IRI was significantly less in both Il17a-/- mice and Il23r/- mice than in WT controls. We also found that pretreatment of WT mice with neutralizing antibody to IL-17A or IL-23 resulted in significant decrease in IRI compared to mice treated with isotype control antibody. Conclusions: These results indicate that IL-17A plays a critical role in IRI. They also suggest that IL-23 contributes to IRI, possibly by promoting IL-17A production.
Targeting sirtuin-1 alleviates experimental autoimmune colitis by induction of Foxp3+ T-regulatory cells (MUC2P.818)
Authors: Akimova Tatiana , Xiao Haiyan , Jiao Jing , Bhatti Tricia , Liu Yujie , Wang Liqing , Hancock Wayne , Beier Ulf 
Published: January 2023

Abstract
Induced Foxp3+ T-regulatory cells (iTreg) are essential to gastrointestinal immune homeostasis and play an important role in preventing autoimmune colitis. We have previously shown that inhibiting sirtuin-1 (Sirt1) can augment Treg function and hypothesized that targeting of Sirt1 might enhance iTreg development and thereby represent a potential therapy for inflammatory bowel disease (IBD). We adoptively transferred CD4+CD25-Foxp3- T effector (TE) cells from wild-type (C57BL/6) or fl-Sirt1/CD4cre mice into B6/Rag1-/- mice and monitored the mice until they lost 10-15% of their weight. Adoptive transfer of TE cells lacking Sirt1 to B6/Rag1-/- mice resulted in increased iTreg formation compared to mice receiving wild-type TE cells (2.3 ±1.6%, vs. 6.2 ±3%, in wild type and fl-Sirt1/CD4cre TE recipients, respectively, p&lt;0.001). This correlated with attenuated colitis and reduced weight loss in fl-Sirt1/CD4cre vs. wild type TE recipients (1.04 ±1.4% vs. 13.97 ±2.2%, respectively, p&lt;0.001). In a second model of IBD, we used pharmacologic Sirt1 targeting of mice receiving multiple cycles of dextran sodium sulfate (DSS) in their drinking water, alternated with fresh water. Likewise, wild-type mice receiving cyclic DSS and a Sirt1 inhibitor, EX-527, had reduced weight loss (5.8 ±5.9% vs. 13.2 ±6.9%, p=0.03) and increased iTreg formation compared to controls. Sirt1 appears a promising target for pharmacologic therapy of IBD as a result of promoting iTreg development.
Gender differences in Crohn's disease are mediated by differential effects of estrogen on T cell function (MUC2P.825)
Authors: Goodman Wendy , Garg Rekha , Davis Calvin , Katz Jeffrey , Cominelli Fabio , Pizarro Theresa 
Published: January 2023

Abstract
Inflammatory bowel disease (IBD) is one of several autoinflammatory diseases for which a female gender bias has been reported. We hypothesized that hormonal signaling may alter T cell function in IBD, since chronic activation of pathogenic T cells drive intestinal inflammation and symptoms of female patients often change during times of altered hormone signaling, such as puberty and pregnancy. We studied the function of regulatory T cells in experimental murine models of ileitis (SAMP1/YitFc) and colitis (CD45RB transfer model), as well as in human IBD patients. In the CD45RB colitis model, CD45RBlow cells (enriched for Treg cells) from WT female mice were less effective at dampening colitis compared to their male counterparts (p&lt;0.001, n=6/group). Consistent with this finding, female SAMP (SAMP-F) mice developed accelerated, worsened ileitis compared to SAMP-M beginning at 6 weeks of age (p&lt;0.01, n=6/group), and displayed reductions in Foxp3 expression and Treg function in vitro. SAMP-F Tregs were non-responsive to estrogen-mediated increases in Foxp3 expression, suggesting that hormone signaling may influence Treg function in ileitis. Lastly, female IBD patients displayed a reduction in Foxp3 expression by FACS compared to males (p≤0.05, n=3/group); this was in contrast to Foxp3 expression in healthy female controls, which exceeded that of healthy males (p&lt;0.01, n=5/group). Together, these data suggest that hormone signaling may directly influence Treg function in IBD.
pRESTO: a toolkit for processing high-throughput sequencing raw reads of lymphocyte receptor repertoires (TECH1P.863)
Authors: Vander Heiden Jason , Yaari Gur , Uduman Mohamed , Stern Joel , O'Connor Kevin , Halfer David , Vigneault Francois , Kleinstein Steven 
Published: January 2023

Abstract
Summary: Driven by dramatic technological improvements, large-scale characterization of lymphocyte receptor repertoires via high-throughput sequencing is now feasible. Although promising, the high germline and somatic diversity, especially of B-cell immunoglobulin repertoires, presents challenges for analysis requiring the development of specialized computational pipelines. We developed the REpertoire Sequencing TOolkit (pRESTO) for processing reads from high-throughput lymphocyte receptor studies. pRESTO processes raw sequences to produce error-corrected, sorted and annotated sequence sets, along with a wealth of metrics at each step. The toolkit supports multiplexed primer pools, single- or paired-end reads, and emerging technologies that employ single-molecule barcodes. pRESTO has been tested on data generated from Roche and Illumina platforms. It has a built in capacity to parallelize the work between available processors, and is able to efficiently process millions of sequences generated by typical high-throughput projects. As part of ongoing collaborations, pRESTO has been applied to multiple B-cell repertoire studies, employing both Roche 454 and Illumina MiSeq sequencing technologies. Availability: pRESTO is freely available for academic use. The software package and detailed tutorials may be downloaded from http://clip.med.yale.edu/pRESTO.
Live cell gene expression detection in monocytes and macrophages through flow cytometry (TECH1P.837)
Authors: Weldon Don , Williams Yuko , Liu Haizhen , Ko Alex , Koong Victor 
Published: January 2023

Abstract
Detecting gene expression in immune cells has traditionally been limited to technologies that utilize a reporter construct for a gene of interest or within lysed or fixed cell populations as is the case for RT-PCR. Here we show the ability to detect gene expression in live monocytes and macrophages which allows for more physiologically relevant information based on the cell’s response to given stimuli. Determining which genes were up or down regulated in those cells provides insight into complex gene regulatory networks and immune cell function. Here we present a novel RNA expression detection technology capable of detecting specific mRNA and miRNA in live, intact cells. This technology allows for detection of target RNA, with the ability to perform downstream assays such as Fluorescence-Activated Cell Sorting (FACS) to enrich for a specific subpopulation of live cells based solely on their RNA expression profile. Following FACS sorting based on RNA detection the cells remain viable and fully functional for use in downstream assays allowing researchers the ability to further characterize or determine functionality of the enriched population. Within a population of cells there is inherent homogeneity which can skew results when only looking at the population level as opposed to understanding the single cell resolution of gene expression. Looking at RNA levels in a more dynamic manner proves to be much more informative than looking at duplicate samples over time.
Role of inflammation in preventing the induction of transplantation tolerance (TRAN1P.876)
Authors: Jangalwe Sonal , Cuthbert Amy , Greiner Dale , Brehm Michael 
Published: January 2023

Abstract
Costimulation blockade targeting the CD40-CD154 pathway is an effective approach to induce tolerance to allografts in murine and non-human primate models. However inflammation generated during infection and exposure to pathogen associated molecular patterns abrogates costimulation blockade induced tolerance. Here we have characterized the alloreactive CD8 T cell response during costimulation blockade in the absence or presence of inflammation. Costimulation blockade consisting of donor splenocytes (DST)/anti-CD154 antibody (MR1) stimulated proliferation of alloreactive CD8 T cells but resulted in deletion of the cells by apoptosis. Exposure to LPS during blockade prevented this deletion, but surprisingly reduced proliferation kinetics of the alloreactive CD8 T cells. These data suggest that LPS increases the frequency of alloreactive CD8 T cells by providing survival signals during cell division. RNA-seq analyses revealed differential expression of genes involved in apoptosis (like Fasl, Perp, Birc5, E2F transcription factors), cell cycle (Ki-67, Bub1, Nusap1), CD8 T cell differentiation and function (granzyme B, T-bet, Eomes) and type I interferon induced genes (Ifi44, Ifit1, Usp18) between the treatment groups. Such phenotypic differences will facilitate identification of pathways that can be targeted to prevent the abrogation of transplantation tolerance in situations of inflammation.