bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel mechanism regulating anti-viral humoral response: interplay between IL-21, LAPC and TFH in anti-IAV humoral response. (P6174)
Authors: Yoo Jae-Kwang , Fish Eleanor , Braciale Thomas 
Published: January 2023

Abstract
The humoral immune response to most respiratory virus infections plays a prominent role in virus clearance and is essential for resistance to reinfection. T follicular helper (TFH) cells are believed to support the development both of a potent primary antibody response and of the germinal center response critical for memory B cell development. Using a model of primary murine influenza A virus (IAV) infection, we demonstrate that a novel APC, the LAPC (Late-activator APC), promotes the TFH response in the draining LNs (dLNs) of the IAV-infected lungs. LAPCs migrate from the infected lungs to the dLN “late,” i.e., 6 d after infection, which is concomitant with TFH differentiation. LAPC migration is CXCR3-CXCL9-dependent, and LAPC triggering of TFH cell development requires ICOS-ICOSL-dependent signaling. In IAV infection, the host immune system control this LAPC-mediated TFH differentiation via IL-21.We have demonstrated that IL-21, a well known TFH differentiation inducing factor, produced by NK T-cells in the dLN acts on lymph node resident T cells to stimulate TNF-α release by the T-cells. TNF-α in turn stimulates dLN resident dendritic cells to secrete CXCL9, a potent chemotactic stimulus for migration of CXCR3 expressing lung resident LAPC into the dLN. It is then the migrant LAPC which acts to modulate TFH differentiation during respiratory viral infection. Our results reveal a novel and previously unsuspected mechanism for regulating anti-viral TFH and humoral responses.
SLAT-IP3R interaction: implications and functional relevance in T cell activation and calcium signaling (P1172)
Authors: Fos Camille , Becart Stephane , Boehning Darren , Yule David , Altman Amnon 
Published: January 2023

Abstract
SWAP-70-like adaptor of T cells (SLAT) is a guanine nucleotide exchange factor for Rho GTPases that regulates the activation and differentiation of CD4+ T cells by controlling the Ca2+-NFAT signaling pathway. In response to T cell receptor (TCR)/CD28 costimulation, SLAT promotes calcium signaling by regulating calcium release from endoplasmic reticulum (ER) stores. Hence, SLAT-deficient T cells display a severe defect in Ca2+ release from the ER, despite normal activation of PLCg1 and intact production of inositol-1,4,5-trisphosphate (IP3). Here we report a direct and TCR-induced association between SLAT and the (IP3) receptor type 1 (IP3R1), an ER-resident calcium channel, which mediates calcium release from intracellular stores. Using biochemical approaches, we found that both a N-terminal domain, containing an EF-hand motif, and the pleckstrin homology (PH) domain of SLAT bind directly a defined ~20 amino acid region in the regulatory domain of IP3R1. Subcellular fractionation analysis showed that SLAT is present in the ER compartment. Altogether, these data prompt us to hypothesize that SLAT is required for proper IP3R function in T cells, reflecting its direct interaction with the IP3R. Current studies, including strategies aimed at blocking and disrupting the SLAT-IP3R1 interaction, are aimed at determining the biological significance of this novel interaction and its importance for the overall TCR/CD28-induced Ca2+ signaling pathway in T lymphocytes.
Pathogenicity of IFN-γ+ Th17 cells is independent of T-bet (P4128)
Authors: Duhen Rebekka , Glatigny Simon , Arbelaez Carlos , Blair Tiffany , Oukka Mohamed , Bettelli Estelle 
Published: January 2023

Abstract
It is now established that T helper (Th) cell subsets, particularly Th17 cells, are more dynamic than originally anticipated and can acquire the expression of other lineage effector cytokines. However, the molecular cues that dictate their plasticity are unknown. We show that IL-23 plays a central role in the plasticity of Th17 cells and is essential for the generation and propagation of IFN-γ-producing Th17 (IL-17+ IFN-γ+) cells. During the development of experimental autoimmune encephalomyelitis (EAE) IL-17+ IFN-γ+ T cells are preferentially expanded in the central nervous system (CNS). Using an IL-17A-IFN-γ double reporter mouse and I-Ab/MOG38-49 tetramer, we determined that they displayed characteristics of pathogenic T cells, such as GM-CSF expression, and contained the highest number of MOG-specific T cells. Interestingly, the Th1-associated transcription factors T-bet, STAT1 and STAT4 were not involved in the induction of IFN-γ by Th17 cells in vitro. Moreover, in contrast to previous studies showing a role for T-bet in Th1 and Th17-mediated EAE, we demonstrate that T-bet expression in T cells is not required for the emergence of CNS-infiltrating IL-17+ IFN-γ+ T cells and the development of Th17-driven EAE. Our results suggest the existence of different epigenetic programs that regulate IFN-γ expression in Th1 and Th17 cells.
FOXP3 isoform expression in atherosclerosis: correlations with plaque inflammation and disease outcome. (P4140)
Authors: Joly Anne-Laure , Liu Sang , Mailer Reiner , Andersson John 
Published: January 2023

Abstract
Atherosclerosis, a chronic inflammatory disease of arteries, is the leading cause of cardiovascular diseases. Innate as well as adaptive immune responses contribute to atherogenesis, with components of cholesterol carrying low-density lipoprotein triggering inflammation, T-cell activation and antibody production during the course of disease. Regulatory T cells (TRegs), known to suppress immune responses and regulate peripheral tolerance, have been shown to attenuate atherosclerosis in experimental models. The transcription factor Forkhead box P3 (FOXP3) protein is the lineage specification factor of TRegs and plays a critical role in upholding the suppressive activity of TRegs. Three splice forms of FOXP3 mRNA exist in human given birth to isoforms with different functional properties. Full length FOXP3 and FOXP3Δ2 confer a suppressive phenotype to TReg cells whereas FOXP3Δ2Δ7 inhibits the function of the other FOXP3 isoforms in a dominant negative manner. Herein we define the relation between FOXP3 isoform expression and the inflammatory response as characterized by cell markers, cytokine expression and expression of costimulatory molecules in human atherosclerotic plaques. We also correlate FOXP3 isoform expression with cardiovascular events post-endarterectomy.
Characterization of the function and co-expression patterns of human FOXP3 isoforms and their role in IPEX syndrome development. (P4146)
Authors: Darrasse-Jeze Guillaume 
Published: January 2023

Abstract
IPEX syndrome is a rare and fatal X-linked recessive disorder due to mutations in the FOXP3 gene, which plays a critical role in the development and function of the regulatory T cells (Tregs) that maintain self-tolerance. Contrary to mice, humans possess three isoforms of FOXP3 with unknown function, and the expression of these isoforms is not restricted to Tregs. We determined the levels of expression and distribution of FOXP3 and other transcription factors isoforms in normal human T-cell subsets and in T cell subsets of patients with autoimmunity at the single-cell level by multiplex RT-qPCR and Flow cytometry and observed that expression of these isoforms is not restricted to Tregs, but can also be detected in naïve and activated/memory helper (Th) and in activated/memory CD8+ T cells. Distinct patterns of co-expression of the FOXP3 isoforms are modulated in response to inflammatory or autoimmune stimuli. Moreover, we observed that normal FOXP3 isoforms could induce bona fide regulatory function in Th cells. Our work supports the view that lack of FOXP3 expression in the effector T-cell populations in IPEX patients may contribute to the pathogenesis of the disease and suggests that FOXP3 deficiency can be corrected by gene transfer of the appropriate FOXP3 isoforms into conventional T-cells, which has important implication for the treatment of IPEX patients.
Realtime immune cell interactions in target tissue during immune damage and protection (P4112)
Authors: Miska Jason , Abdulreda Midhat , Devarajan Priyadharshini , Lui Jen Bon , Suzuki Jun , Pileggi Antonello , Berggren Per-Olof , Chen Zhibin 
Published: January 2023

Abstract
Realtime imaging studies are reshaping immunological paradigms, but a visual framework is lacking for the cellular dynamics of self-antigen-specific T cells at the effector phase in target tissues. To delineate key events in the cascade of tissue damage, immune protection and tissue response, we conducted noninvasive longitudinal imaging at a cellular resolution. We report that for both CD4+ and CD8+ effector T (Teff) cells, destruction was associated with close proximity to targets. Antigen-specificity is a prerequisite of target killing. Strikingly, incongruent to a classic concept of bystander killing, juxtaposed β-cell mass lacking the specific antigen was not subject to destruction, but grew in days, likely by replication. In the target tissue, Foxp3+ regulatory T (Treg) cells persistently contacted Teff cells, providing the first in vivo evidence consistent with the in vitro “trademark” activity of Treg cells, contact-dependent suppression. Modulating cytotoxic T lymphocyte antigen-4 (CTLA4) altered Treg-Teff cell interactions and unleashed Teff cells to inflict further damage. This study demonstrates the importance of contact-based immune cell interaction and suggests that an intimate choreography between destructive and protective immune cells is critical for tolerance induction in target tissues. It also highlights the potential of tissue regeneration under antigenic incognito in inflammatory settings.
Hijacking of microparticle transcellular communication: a means of protein delivery and alteration of cell function (P3257)
Authors: Sahler Julie , Woeller Collynn , Spinelli Sherry , Blumberg Neil , Phipps Richard 
Published: January 2023

Abstract
Microparticles are submicron vesicles present in blood and other fluids that influence cells such as lymphocytes, monocytes, endothelial cells, etc. Microparticle composition is derived from the parent cell and determines the “message” communicated to other cells. Platelets and megakaryocytes produce about 80% of circulating microparticles. We aimed to usurp this unique means of transcellular communication by manipulating microparticle composition in order to deliver proteins to target cells to influence their function. We used a lentiviral vector for the transduction of a human megakaryoblastic cell line, thus changing the protein composition of generated platelets and microparticles. We successfully engineered microparticles to overexpress the anti-inflammatory transcription factor peroxisome proliferator activated receptor-γ (PPARγ) along with GFP. These genetically enhanced microparticles were taken up by the monocytic cell line THP-1 and by primary endothelial cells, and this uptake was enhanced by PMA activation. Importantly, the transfer of PPARγ was functional, in that, microparticles that overexpressed PPARγ caused THP-1 cells to increase transcription of a PPARγ target gene, fatty acid binding protein 4. This proof of concept alteration of microparticle composition and subsequent functional changes in target cells provide an important new tool for therapeutic delivery of proteins, which could be developed into new anti-inflammatory or adjuvant therapies.
Segmentation: a novel approach to immune profile analysis of the human lymph node microenvironment (P3261)
Authors: Blenman Kim , Lee Peter 
Published: January 2023

Abstract
In the lymph node microenvironment, many cells interact to provide cues for immune cell activity. Understanding the composition and spatial relationships between cells is key in deciphering mechanisms responsible for immune responses. Our novel method expands the use of immunohistochemistry (IHC) by generating quantitative immune profiles. Our integrated approach includes multiplexed IHC, high-resolution multispectral automated whole-slide scanning, and image analysis via software. Our image analysis segments cells into phenotypes and tissues into regions. In this pilot study, we compared tumor-infiltrated (Tpos) and tumor-free (Tneg) tumor-draining lymph nodes (TDLNs) from breast cancer patients. We segmented images into non-immune cell (NIC), extrafollicular (ExF), follicular (F), and tumor tissue regions. We segmented cells by five-color IHC into T cell (CD4, CD8, and Foxp3) and tumor (cytokeratin) phenotypes. Globally and compartmentally (NIC, ExF, and Tumor), there were more immune cells in Tpos TDLNs. However, in F regions, there were less immune cells in Tpos TDLNs. There were more NIC regions but less ExF and F regions in Tpos TDLNs. We also found less NIC, ExF, and F regions in relapsed vs. disease-free patients. Our segmentation analysis may provide valuable data on cell distribution and spatial relationships within specific tissue regions. Our next steps are to use this method to help define mechanisms of action for tumor metastasis and predict clinical outcome.
Automatic pathogen introduction and removal for live cell imaging of host-pathogen interaction (P3237)
Authors: Hung Paul 
Published: January 2023

Abstract
Host-pathogen interactions represent a significant area of immunology, encompassing the study of how organisms cause infections and diseases. As the field advances, there is increasing interest in using in vitro cell culture models and imaging to study the interactions. However, a few barriers remain with the conventional static cell culture approach. Not only the pathogen will easily outgrow the cells over time, prohibiting further studies, but tedious liquid exchange steps are required to remove excessive pathogens or to add other reagents such as therapeutic compound. To facilitate host-pathogen interaction research with live cell imaging, a microfluidic platform which addresses the problems mentioned above was developed. The platform allows the researchers to culture the cells in a microchamber on a standard inverted microscope, as well as preload up to four different reagents which can be introduced to the cells automatically including the pathogen. The reagent switching function enable the removal of pathogens from the chamber after incision, and subsequent monitoring of host cell response over up to 3 days. The enclosed small volume microchamber also provides practical advantages for working with infectious agents during live cell imaging. An experiment using human intestinal cells infected with engineered E. coli strains was demonstrated. Both an invasive and a non-invasive bacterial strain were monitored for infection with time-lapsed imaging up to 24 hours.
R10K update: NGS of immune repertoire for biomarker discoveries (P3241)
Authors: Han Jian , Wang Chunlin , Byrne-Steele Miranda , Alleyne Jessica , Yang Qunying , Myers Richard 
Published: January 2023

Abstract
The natural duty of the adaptive immune system is to detect any internal and external threats and mount specific and measured reactions accordingly. Therefore, the immune repertoire is rich in specific diagnostic markers. We have developed a novel multiplex PCR method, which can amplify the CDR3 regions from a sample inclusively and semi-quantitatively. The PCR products can be sequenced directly with different next generation sequencing platforms. A software package was developed to filter out amplification and sequencing errors, identify CDR3 sequences and perform routine repertoire analysis. The R10K project (www.R10K.org) is organized and supported by the HudsonAlpha Institute for Biotechnology, a nonprofit research institute specialized in genomic research. The project is an international collaborative effort to sequence 10,000 samples and study 100 diseases. Our pilot studies have demonstrated that disease specific repertoire changes can be detected. Quantitatively, the changes in repertoire diversity can be used as a biomarker for disease staging and measuring treatment response. Qualitatively, detection of disease specific CDR3s can be used for early diagnosis of diseases, including cancer, autoimmune diseases, inflammatory diseases, and infectious diseases. The R10K project is open to collaborators; the IP rights are shared among collaborators, participating institutions and companies. The data will be publicly available as each study is completed.
Posttranscriptional gene regulation of IL-17 by the RNA-binding protein HuR is required for initiation of autoimmune neuroinflammation (P6273)
Authors: Chen Jing , Cascio Jason , Magee Joseph , Techasintana Patsharaporn , Gubin Matthew , Garrett Dahm , Calaluce Robert , Atasoy Ulus 
Published: January 2023

Abstract
Interleukin 17 (IL-17) is a proinflammatory cytokine produced by activated Th17 T cells. Th17 cells are major contributors to autoimmune diseases, such as multiple sclerosis. Although the transcriptional regulation of Th17 cells is well understood, its posttranscriptional regulation is unclear. The RNA-binding protein HuR regulates the stability of many target mRNAs via binding the AU-rich elements (ARE) present in the 3’ untranslated region (UTR), including inflammatory cytokines such as IL-4, IL-13 and TNF-α. The regulation of IL-17 expression by HuR has not been established. We reported that production of mRNA and protein levels of IL-17, produced by polarized Th17 cells from HuR conditional knockout (KO) mice, were abrogated. Moreover, we demonstrated that HuR directly bound to IL-17 mRNA 3’ UTR by using immunoprecipitation and RNA precipitation (RIP) and biotin pull down assays. Th17 cells from HuR conditional KO mice had decreased IL-17 steady-state mRNA and protein levels compared to wild type cells. Mice with adoptively transferred HuR KO CD4+ T cells had delayed onset and reduced severity of experimental autoimmune encephalomyelitis (EAE) compared to wild type CD4+ T cells. Our results reveal a posttranscriptional regulatory mechanism of Th17 cells by HuR, which may provide novel therapeutic targets for treatment of IL-17- mediated autoimmune neuroinflammation.
IFN-γ signaling in astrocytes and microglia has opposite roles in CNS autoimmunity (P5170)
Authors: Zhang Guang-Xian , Yan Yaping , Ding Xiaoli , Li Ke , Ciric Bogoljub , Yang Jingxian , Wu Shuai , Xu Hui , Chen Wanjun , Lovett-Racke Amy , Rostami Abdolmohamad 
Published: January 2023

Abstract
IFN-γ, the hallmark cytokine of Th1 cells, plays an important role in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Thus far, the role of IFN-γ in EAE has been largely studied through its effects on immune cells, while much less is known about its effects on central nervous system (CNS) cells, especially in vivo. In this study we for the first time dissected the in vivo effects and mechanisms of IFN-γ signaling in astrocytes and microglia and found that IFN-γ signaling in these cell types has opposite effects in EAE pathogenesis. Silencing IFN-γ signaling in astrocytes ameliorated EAE, while in microglia it increased disease severity. Silencing IFN-γ signaling in astrocytes resulted in diminished expression of chemokines and fewer inflammatory cells infiltrating into the CNS, while blocking IFN-γ signaling in microglia increased disease severity through augmented activation and proliferation of microglia. Further, blocking IFN-γ signaling in astrocytes ameliorated both Th1- and Th17-mediated adoptive EAE, indicating an important role for IFN-γ signaling in astrocytes in autoimmune CNS inflammation. Thus, our study defines novel mechanisms of action of IFN-γ in EAE pathogenesis, and also highlights an opportunity for development of MS therapies directed at CNS cells.
Reciprocal modulation of CD4 T cell responses by intravenous immunoglobulin in experimental autoimmune encephalomyelitis (P5178)
Authors: Othy Shivashankar , Hegde Pushpa , Topçu Selma , Sharma Meenu , Maddur Mohan , Lacroix-Desmazes, Sebastien , Käsermann Fabian , Miescher Sylvia , Bayry Jagadeesh , Kaveri Srini 
Published: January 2023

Abstract
IVIg is increasingly used for therapy in many autoimmune and inflammatory diseases; however the mechanisms underlying its therapeutic benefit have remained uncertain. We have investigated the mechanisms in the context of modulation of regulatory and pathogenic CD4 T cells in EAE, a murine model of multiple sclerosis. We demonstrate that IVIg delays the onset of EAE by inhibiting encephalitogenic CD4 T cell subsets (Th1 and Th17 cells) and concomitantly expanding foxp3+ regulatory T cells. Furthermore, IVIg renders effector T cells less pathogenic by decreasing the expression of encephalitogenic molecules such as GM-CSF and podoplanin. Intriguingly and contrary to the current arguments, the inhibitory FcγRIIB and sialylation on IgG are dispensable and F(ab’)2 fragments retained this function of IVIg. Additionally, IVIg sequestered effector T cells into the draining lymph nodes leading to decreased infiltration into CNS. IVIg interfered with S1P-S1P1-mTOR pathway to sequester lymphocytes in the draining lymph nodes and reciprocally regulate CD4 T cell subsets. Our study reveals a novel role of immunoglobulins in modulating polarization, pathogenicity and trafficking of T lymphocytes accounting for the observed beneficial effect during IVIg therapy.
Regulatory B cells suppress experimental autoimmune myasthenia gravis via production of IL-10 (P5145)
Authors: Sheng Jianrong , Prabhakar Bellur , Meriggioli Matthew , Soliven Betty 
Published: January 2023

Abstract
Autoimmune Myasthenia Gravis (MG) is T cell-dependent, B cell mediated autoimmune disorder in which autoantibodies are produced targeting the skeletal muscle acetylcholine receptor (AChR). Previous studies have shown that regulatory T cells (Tregs) have the capacity to prevent and reverse experimental autoimmune MG (EAMG). In more recent investigations, our studies showed that regulatory B cells (B10 cells) produced high level of IL-10 and suppressed ongoing experimental autoimmune MG (EAMG), resulting in a significant down-modulation of relevant pathogenic anti-AChR autoantibody production and significant preservation of muscle AChR content. In in vitro co-culture studies, B10 cells altered T cell cytokine profiles through increasing IL-10 production and decreasing IFN-r production of CD4+ T cells, but did not directly inhibit T cell proliferation. On the other hand, B10 cells can inhibit B cell proliferation and its autoantibody production in vitro through IL-10 production. Thus, Our studies has provided the significant insights into the nature of the mechanism and effects of regulatory B cells in EAMG. These observations suggest that mobilization of B10 cells in vivo/vitro may represent an effective strategy in the treatment of human MG.