bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new mTOR-dependent, Akt-independent pathway differentiates the migratory behavior of regulatory and conventional T cells (CAM1P.235)
Authors: Raimondi Giorgio , Chen Leo , Rosborough Brian , Thomson Angus 
Published: January 2023

Abstract
The vitamin A metabolite all-trans retinoic acid (ATRA) induces a gut-homing phenotype in activated CD4+ conventional T cells (Tconv) by upregulating the integrin α4β7 and the chemokine receptor CCR9. We report that in contrast to mouse Tconv, only half of regulatory T cells (Treg) upregulate CCR9 when stimulated in presence of ATRA, even though Tconv and Treg express identical levels of receptor (RAR). The bimodal distribution of CCR9+ versus CCR9- Treg subsets is not associated to differences in proliferation, level of FoxP3 expression, or segregation between thymic-derived and induced Treg. Furthermore, exposure to the mTOR inhibitor rapamycin suppresses upregulation of both CCR9+ and α4β7 on Treg, an inhibitory effect not evident in Tconv. This suggests that ATRA-induced upregulation of CCR9 and α4β7 on Treg is dependent on activation of an mTOR signaling pathway. This mTOR involvement is independent of Akt activity, since specific inhibition of Akt or its downstream target GSK-3B did not prevent CCR9 expression. Additionally, Rictor-/- Treg (that lack mTORC2) showed unaltered expression of CCR9 compared to WT control, suggesting participation of mTORC1 or another mTOR complex. These findings reveal a novel difference between ATRA signaling and chemokine receptor induction in Treg versus Tconv, and provide a framework via which the migratory behavior of Treg versus Tconv can be differentially influenced for therapeutic purposes.
Absence of L-selectin accelerates atherosclerosis via the modulation of B cell subsets and local immune response within the aortas of L-selectin-deficient Apoe-/- mice. (CAM1P.236)
Authors: Galkina Elena , Taghavie-Moghadam Paresa , Ley Klaus , Gjurich Breanne 
Published: January 2023

Abstract
To date, a significant body of evidence implicates the immune system in atherosclerosis. Studies report that follicular B cells are pro-atherogenic whereas B1a cells play a protective role; yet the role of other B cell subsets is unclear. The mechanisms behind the regulation of cell subset specific homing into aortas are not well understood. To determine the role of L-selectin in atherosclerosis, we bred L-selectin deficient (Sell-/-) and Apoe-/- mice and generated Sell-/-Apoe-/- mice. L-selectin deficiency resulted in accelerated atherosclerosis that was accompanied by a 1.3-fold increase in the number of leukocytes within aortas of Sell-/-Apoe-/- mice. However, Sell-/-Apoe-/- aortas displayed a 2-fold reduction in aortic B cells. Importantly, L-selectin deficiency significantly reduced the percentage and number of B1a and regulatory B (Breg) cells within Sell-/-Apoe-/- compared to Apoe-/- aortas and spleens. We found more B1a expressing L-selectin compared with splenic FO B cells, suggesting a potentially high dependence of B1a cells from L-selectin. With the reduction of aortic B1a and Breg, there were reduced IL-10 levels in Sell-/-Apoe-/- aortas. In line with the increased aortic leukocyte cellularity, there was a 1.5-fold increase in aortic CD68hi macrophages. These data provide evidence for a functional role of L-selectin in atherosclerosis via the regulation of the content of aortic B1a and Breg cells and the modulation of the local immune response within the aorta.
Dynamic regulation of LFA-1 and Mac-1 during neutrophil extravasation in live mice (CAM1P.232)
Authors: Hyun Young-Min , Capece Tara , Lim Kihong , Wong Jennifer , Kim Minsoo 
Published: January 2023

Abstract
LFA-1 (CD11a/CD18) and Mac-1 (CD11b/CD18) are key integrins that regulate leukocyte adhesion and migration in inflamed tissues. Despite considerable advances in our understanding of leukocyte migration, real-time regulation of leukocyte integrins in vivo is not well characterized. To this end, we generated knock-in mice in which CD11a, CD11b, and CD18 were fused with mYFP and mCFP, respectively, to generate the CD11a-mYFP, CD11b-mYFP, and CD18-mCFP mice. We then crossed these mice to generate LFA-1 FRET (CD11a-mYFP/CD18-mCFP) and Mac-1 FRET (CD11b-mYFP/CD18-mCFP) mice. Using FRET assay with multiphoton intravital microscopy (MP-IVM), we now can directly measure LFA-1 and Mac-1 activation during neutrophil extravasation in inflamed tissues. Neutrophils showed distinct patterns of distribution of active integrins and their clustering at different steps in the multistep extravasation cascade. Experiments with blocking antibodies and knock-out mice confirmed that LFA-1 and Mac-1 are regulated by distinct activation kinetics in vivo. Our data suggest that these knock-in mice will be useful to visualize the subcellular distribution and activation of LFA-1 and Mac-1 in real-time during leukocyte migration in intact tissues.
Mouse iNKT cell development and functions are differentially regulated by SHIP-1 (HEM3P.288)
Authors: Anderson Courtney , Salter Alexander , Reilly Emma , Toussaint Leon , Kerr William , Brossay Laurent 
Published: January 2023

Abstract
The SH2-containing inositol phosphatase-1 (SHIP-1) is a 5’ inositol phosphatase known to negatively regulate the signaling product of phosphoinositide-3 kinase (PI3K), phosphatidylinositol (3,4,5)-trisphosphate (PI(3,4,5)P3). SHIP-1 can be recruited to a large number of inhibitory receptors expressed on iNKT cells. We hypothesized SHIP-1 deletion would have major effects on iNKT cell development by altering the thresholds for positive and negative selection. In SHIP-1 deficient animals, iNKT cell frequency and number are impaired when compared to littermate controls. However, using both mixed bone marrow chimera and mice conditionally deficient for SHIP-1 in the T cell lineage, we show iNKT cell development is globally intact, demonstrating SHIP-1 is not required intrinsically for iNKT cell development. In addition, although SHIP-1 is necessary extrinsically for iNKT positive selection, it is dispensable on CD1d positive selecting cells. Interestingly, SHIP-1 deficient iNKT cells display functional defects including reduced cytokine production. These results further our understanding of how iNKT cell activation is regulated and provide insights into the biology of this unique cell lineage.
Id3 and Id2 collaboratively regulate innate-like γδ T cell development (HEM3P.275)
Authors: Zhang Baojun , Lin Yenyu , Dai Meifang , Zhuang Yuan 
Published: January 2023

Abstract
γδ T cells expressing the Vγ1.1 and Vδ6.3 TCR chains are one of growing numbers of recently characterized innate-like lymphocytes. Id3 has been shown to be a major transcription regulator to prevent the development and expansion of this population. We showed that deletion of Id3 resulted in a dramatic expansion of Vγ1.1Vδ6.3 T cells on the C57BL/6 background. This phenotype is in contrast to the much milder phenotype when the Id3 mutation was initially characterized on the 129/sv background. We conducted a quantitative trait analysis in search of the presumed Id3 modifier(s). Id2 was mapped as a major modifier of Id3 in suppressing Vγ1.1Vδ6.3 cell expansion. This mapping result was further confirmed by introduction of the targeted allele of Id2 to the Id3 mutant background. Our study led to four major observations: first, a decrease in Id2 expression on Id3 deficiency background promotes expansion of Vγ1.1Vδ6.3 cells. Second, complete elimination of both Id2 and Id3 genes triggers apoptosis instead of further expansion of Vγ1.1Vδ6.3 cells. Third, Id3 and Id2 collaboratively control survival and expansion of the γδ lineage through regulating a proper threshold of E proteins. Finally, Id proteins seem to control cell survival and expansion post Vγ1.1Vδ6.3 lineage specification. Based on these findings, we propose a dual safety mechanism to explain the role of Id3 and Id2 in regulating the population size of Vγ1.1Vδ6.3 T cells.
Injury-induced vascular intimal hyperplasia is mediated through a HMGB1- and TLR4- driven mechanism (HUM1P.304)
Authors: Cai Jingjing , Yuan Hong , Wang Qingde , Yang Huan , Billiar Timothy , Chen Alex F. 
Published: January 2023

Abstract
Aim: To determine whether high-mobility group box 1 (HMGB1) and Toll like receptor 4 (TLR4) drive the inflammatory cascade that promotes intimal hyperplasia (IH) following acute vascular injury. Methods and Results: Carotid artery wire injury in C57BL/6 mice induced a significant increase in intima to media (I/M) ratio at four weeks. Global deletion of HMGB1 using an inducible knockout mouse strain caused prevention of IH. IH was decreased by over 50% in WT mice treated with HMGB1 neutralizing antibody. Of knockout mouse strains deficient in putative receptors for HMGB1, TLR4-/- mice showed the greatest inhibition of IH. Both anti-HMGB1 treated mice and TLR4-/- mice exhibited a marked decrease in monocytic recruitment. Mice with selective depletion of TLR4 from macrophage exhibited a similar level of inhibition of IH to that seen in the global TLR4-/-. In vitro, dithiol HMGB1 dose-dependently promoted SMC migration and MCP-1/CCR2 expression, which was abolished by TLR4 inhibitory peptide. Conditioned media from HMGB1 treated macrophage induced SMC proliferation and SMC mitogen production, which was also diminished by blocking TLR4 on macrophages. Conclusion: Innate immune mechanism known to be involved in the sterile inflammatory response are involved in the acute vascular injury responses leading to IH. HMGB1 promotes IH by inducing vascular SMC migration and chemokine production via TLR4 pathway while simultaneously triggering SMC mitogen release by infiltrating monocytes.
Host genotype interaction with cigarette smoke determines modulation of immune response (HUM2P.342)
Authors: Taneja Veena 
Published: January 2023

Abstract
While the etiology of rheumatoid arthritis (RA) is unknown, both genetic and environmental factors are involved in pathogenesis. Among genetic factors, HLA-DRB1*0401/DQ8 provide the strongest association. Among environmental factors, Cigarette smoking (CS) has been associated with a 2-fold increase in risk for developing seropositive RA; specially individuals carrying DRB1*0401 who smoke cigarettes. It has been hypothesized that the response to Vimentin precedes the onset of RA. To determine the interaction between genetic factors and CS, we generated transgenic mice expressing RA-susceptible DRB1*0401 and DQ8 genes in the absence endogenous class II molecules. To determine how cigarette smoke (CS) interacts with host genetic factors in the induction of RA-associated autoimmunity, we used transgenic mice carrying the RA-susceptible HLA genes DR4 and DQ8, but lacking all endogenous murine class II molecules. Cigarette smoke exposure augmented immune responses to citrullinated synovial antigens, collagen and vimentin. Interestingly, CS exposure suppressed collagen-induced arthritis (CIA) in DRB1*0401 mice even though innate immune response was enhanced. On the other hand, CS exposure exacerbated CIA in DQ8 mice, which was accompanied by an increased expression of Th17 gene transcripts in lungs. These observations suggest that cigarette smoke promotes antigen-specific autoimmunity that is profoundly influenced by host genetic factor.
Inflammatory disease due to selectively impaired NF-kB activation and type I interferon response resulting from a de novo human NEMO hypomorphic mutation (HUM2P.333)
Authors: Wessel Alex , Hsu Amy , Goldbach-Mansky Rapheala , Zilberman-Rudenko Jevgenia , Siegel Richard , Hanson Eric 
Published: January 2023

Abstract
Hypomorphic mutation of the NF-kB essential modulator (NEMO) causes a spectrum of inflammatory disease and immunodeficiency. NEMO is critical in immunity, regulating the activation of transcription factors NF-kB and IRF3 to control inflammation and antiviral type I interferon. In an individual with persistent inflammatory disease, we identified a synonymous mutation in the gene encoding NEMO that enhances alternative splicing and production of a mutant protein (Δ-NEMO). Co-immunoprecipitation studies in patient T cells revealed impaired association of Δ-NEMO with TANK (TRAF family member-associated NF-kB activator) and, consequently, with the IRF3 kinase TANK-binding kinase 1 (TBK1). Concomitantly, patient fibroblasts displayed impaired production of IRF3-dependent type I and III interferon in response to poly(I:C) and permitted increased virus propagation. However, cells containing Δ-NEMO exhibited enhanced IRF3 nuclear translocation and binding to the IFNB1 promoter. Our results suggest that defective interferon production in this patient lies instead in impaired NF-kB activation, as poly(I:C)- and 5’pppRNA induced translocation of NF-kB in patient fibroblasts was reduced. This impairment in NF-kB was specific, as TNF-induced NF-kB activation and gene induction was normal. These data describe a novel mechanism of autoinflammatory disease due to a type I interferon deficiency. Thus, this represents a model of inflammatory diseases responsive to type I IFN therapy.
Structure-function relationships that govern FcεRI signaling by allergens (HYP3P.344)
Authors: Wilson Bridget , Mahajan Avanika , Lidke Diane , Tung Chang-Shung , Manavi Kasra , Tapia Lydia , Bradbury Andrew , Hlavacek William 
Published: January 2023

Abstract
Multivalent antigens trigger robust FcεRI-dependent signaling responses in mast cells and basophils. Most prior studies have relied on chemically heterogenous artificial ligands, rendering it difficult to predict receptor cluster size and orientation and to translate the observations to clinical relevance. This work focuses on the use of structurally defined polyvalent antigens to crosslink IgE-FcεRI, including a symmetrical trivalent ligand (DNP3-fibritin) and natural allergen (shrimp tropomyosin). In silico docking and computer simulation methods were used to build structural models of ligand-IgE-FcεRI ectodomain complexes and to estimate aggregation properties, including distances between individual receptors after crosslinking. Signaling responses were studied in “humanized” RBL-2H3 cells and in human basophils from allergic subjects. High resolution imaging approaches were employed to provide insight into the kinetics of crosslinking and the nanoscale organization of FcεRI signaling. The bell-shaped secretory responses are shown to be linked to the balance of positive (Syk-mediated) and negative (SHIP-mediated) signaling, as well as to differences in aggregate size, complexity and time course. Structurally defined antigens provide an improved basis for understanding FcεRI signal initiation and termination. These studies lay the foundation for understanding the essential structural features of natural allergens, such as valency, epitope distance and affinity.
The ribonucleotide reductase inhibitors didox and trimidox suppress IgE-stimulated mast cell cytokine secretion (HYP3P.350)
Authors: McLeod Jamie , Elford Howard , Ryan John 
Published: January 2023

Abstract
Ribonucleotide reductase is the enzyme responsible for catalyzing the production of deoxynucleotide triphosphates (dNTPs), essential for proper DNA synthesis and cell cycle progression. Inhibitors of ribonucleotide reductase have become attractive therapeutic agents for the treatment of conditions characterized by excessive cell proliferation or inappropriate immune cell activation, including myeloproliferative disorders, psoriasis and cancer. Late phase IgE-stimulated mast cell (MC) activation elicits sustained inflammation and is marked by synthesis and secretion of cytokines that have been implicated in the inflammatory responses associated with rheumatoid arthritis, multiple sclerosis and heart disease. Given the potential utility of ribonucleotide reductase inhibitors as cytostatic agents that may influence immune cell activation, we investigated the anti-inflammatory abilities of Didox and Trimidox as a therapeutic approach to attenuate the allergic response. Our results have found that Didox and Trimidox pre-treatment yields a dose-dependent reduction in IgE-stimulated bone marrow-derived mast cells (BMMC) cytokine secretion. These effects are not directly linked to an increase in cell death. Together this preliminary data could indicate a role for Didox and Trimidox in the treatment of MC-associated inflammatory and autoimmune diseases.
LjC1qDC-1, a novel C1q-domain containing protein from lampetra japonica involving in the immune response (INM2P.428)
Authors: Li Qingwei , Pang Yue , Liu Ge , Wang Shiyue , Pan Xiong 
Published: January 2023

Abstract
The C1q domain containing (C1qDC) proteins are defined as a family of all proteins containing the globular C1q (gC1q) domain in the C-terminus. They participate in a series of immune responses depending on versatile gC1q domain which can bind a variety of self and non-self ligands. In this study, a novel C1qDC protein was identified from Lampetra japonica (designated as LjC1qDC-1). Its full-length cDNA was of 1662 bp with an open reading frame (ORF) of 711 bp encoding a polypeptide of 236 amino acids. The deduced protein contained a signal peptide, a collagen-like sequence with Gly-Xaa-Yaa repeats, and a typical gC1q domain. Real-time PCR analysis showed that the transcript of LjC1qDC-1 gene was distributed in various immune associated tissues of lamprey. This observation was further confirmed by FACS and confocal laser scanning microscope. In addition, LjC1qDC-1 interaction with specific VLR was analysised by co-immunoprecipitation and western blot. All these results indicated that LjC1qDC-1 gene identified may play an important role in the immune responses of lamprey, which provided a clue to understand the universal function of C1qDC proteins in different species.
Differential expression profile of long non-coding RNAs from Gr-1+ CD11b+ myeloid cells in response to sepsis in mice (INM2P.424)
Authors: Shu Qiang 
Published: January 2023

Abstract
Background: Emerging evidence shows that small noncoding RNAs are involved in the immune response to sepsis. While, whether long noncoding RNAs (lncRNAs) are associated with the immune response to sepsis is currently unexplored. So we performed a global expression profile of lncRNAs from myeloid-derived suppressor cells (MDSCs), which are an important population that mediate immune suppression in response to sepsis, defined by the cell-surface phenotype Gr-1+ and CD11b+. Methods: Sepsis was induced by cecal ligation puncture (CLP) in mice. MDSCs were sorted from spleens by magnetic selection and FACS 72 h after CLP or sham surgery. The Arraystar lncRNA microarray was used to profile the genome-wide lncRNA expression. The expression pattern and classification of lncRNAs were evaluated by bioinformatics. Results: The microarray provided 16,551 lncRNAs in the septic group and 17,381 in the sham group. After sepsis, among the lncRNAs expressed in both groups, 139 were upregulated and 268 downregulated by ≥ 1.5-fold compared with sham. Nearly half of the differentially-expressed lncRNAs were intergenic RNAs. qRT -PCR confirmed the lncRNA expression pattern of microarray hybridization. Conclusions: The present study provided the first global profile of lncRNA expression in response to sepsis. The expression pattern of lncRNAs in MDSCs was affected by sepsis. Future researches are needed to determine candidate lncRNAs as biomarkers or therapeutic targets for sepsis.
PD-1 inhibits Th1 responses during cryptococcus neoformans infection (IRC2P.452)
Authors: McBerry Cortez , Sakai Shunsuke , Kauffman Keith , Barber Daniel 
Published: January 2023

Abstract
PD-1 is an inhibitory receptor expressed on the surface of activated T cells. PD-1 previously has been shown to play a significant role in regulating effector T cell responses against viral infections and tumors. However, its role in the control of CD4 T cell responses during infection with fungal pathogens remains poorly understood. Here we examine the role of PD-1 in regulating host responses and resistance to the opportunistic fungal pathogen Cryptococcus neoformans. We find that in wild-type mice C. neoformans elicits Th1, Th2, and Th17 responses, and PD-1 is expressed on each of these effector T cell subsets. In PD-1 deficient mice, the frequency of IFN-γ-producing and t-bet expressing CD4+ T cells were increased, while CD4+ T cells making IL-13, IL-5, and IL-4 were decreased and Th17 responses were unchanged. Also, PD-1 deficient mice show a decrease in eosinophils in the lung, and in fungal burden. These data suggest that PD-1 impairs host resistance to C. neoformans by selectively inhibiting Th1 responses. The work was supported by the NIH Intramural Research Program.
Actin-binding protein 1 links B-cell receptor to negative signaling pathways (IRC3P.462)
Authors: Song Wenxia , Seeley-Fallen Margaret , Onabajo Olusegun , Tan Tse-Hua , Upadhyaya Arpita 
Published: January 2023

Abstract
Prolonged or uncontrolled B-cell receptor (BCR) signaling is associated with autoimmunity. We previously demonstrated a role for actin in BCR signal attenuation. This study reveals that Actin-binding protein 1 (Abp1/HIP-55/SH3P7) is a critical negative regulator of BCR signaling, and is responsible for linking actin remodeling to negative regulatory pathways of the BCR. In Abp1 knockout mice, the numbers of spontaneous germinal center B cells and marginal zone B cells are significantly increased, while early B-cell development is unaltered. Serum levels of autoantibody and total antibody are elevated, while T-dependent antibody responses are markedly reduced. Upon activation, surface BCR clustering is enhanced and B-cell contraction is delayed in Abp1-/- B cells; concurrent with slow but persistent increases in F-actin at BCR signalosomes. Furthermore, BCR signaling is enhanced in Abp1-/- B cells compared to wild-type B cells, including increased levels of Ca2+ flux and phosphorylated BLNK, MEK1/2 and ERK, coinciding with reductions in the recruitment of the inhibitory signaling molecules HPK1 and SHIP-1 to BCR signalosomes. Our results indicate that Abp1 contributes to the maintenance of B-cell tolerance via negatively regulating BCR signaling, by promoting actin-dependent B-cell contraction and activation of inhibitory signaling molecules. This reveals a new mechanism for negative regulation of BCR signaling.
A unique population of induced age associated B cells (iABC) are generated in aged mice in response to IAV (IRC3P.465)
Authors: Zhang Wenliang , Kuang Yi , Swain Susan 
Published: January 2023

Abstract
With age, mice generate lower levels of isotype-switched IgG antibody (Ab) following immunization with influenza A (IAV). The total IgG and all the IgG isotypes in serum are 10-100-fold lower in aged mice. In contrast the levels of IgM are roughly equivalent to those of young ones. We find defects in germinal center Tfh in the aged that likely contribute to poor IgG response. We analyzed whether there were also intrinsic changes in the aged B cells that favor IgM production. We found a unique population of Fashi/GL7neg induced age-associated B cells (iABC) after IAV infection containing many IgM-secreting plasma cells (PC). The iABC were detected as early as 3 days post infection in secondary lymhoid sites and their generation was CD4 T cell independent. In the bone marrow 60% of the IgM+ PC were from iABC, while traditional follicular B cells gave rise only to IgM- plasma cells. Thus an alternate source of IAV-specific Ab is generated in infected aged mice that may contribute promote viral clearance. This finding may provide a new target for immunotherapies and strategies for improving antibody response in the elderly.