bluuebunny/crossref_metadata_2025_split huggingface dataset:
Toll like receptor 7 antagonist IRS661 inhibits insulitis and autoimmune diabetes in non-obese diabetic mice (P5227)
Authors: Zhang Yiqun , Chang Emily , Dutz Jan 
Published: January 2023

Abstract
Toll like receptor 7 (TLR7) stimulation activates DCs and T cells to promote autoimmune diabetes in non-obese diabetic (NOD) mice. The aim of the study was to investigate effects of TLR7 antagonist IRS661 on type 1 diabetes onset, insulitis and immune responses in NOD mice. Female NOD mice were treated with IRS661 at ages of 4, 6 and 8 weeks or with either ODN1982 or PBS as control groups. Blood glucose was measured weekly, and pancreas, pancreatic lymph nodes (PLNs) and spleens were obtained for histology analysis or FACS analysis. This treatment significantly inhibited the onset of diabetes, as 6/15 NOD mice treated with IRS661 developed diabetes by 30 weeks of age, compared to 8/8 ODN1982-treated or 13/15 PBS groups (p&lt;0.001). Further, insulitis scores were lower and pancreatic islets were preserved in NOD mice treated with IRS661. To determine effects of IRS661 upon immune responses, NOD PLN cells or splenocytes were analyzed after the treatment. IRS661 diminished CD86 expression on DCs and IFN-α expression in plasmacytoid DCs in NOD PLNs. Further, IRS661 treatment decreased IGRP V7+ CD8 T cells and CD69 expression on CD8 T cells, and inhibited adoptively transferred BDC 2.5 CD4 T cell proliferation in NOD PLNs. No difference in CD25+Foxp3+ CD4 T regulatory cells between IRS661-treated or ODN1982-treated NOD splenocytes was detected. We conclude that IRS661 administration inhibits activation of DCs and CD8 T cells so as to decrease insulitis and diabetes onsets.
Fms-like tyrosine kinase 3 ligand-Fc chimera suppresses autoimmune demyelinating disease (P5228)
Authors: Burke Thomas , Tu Hua , Lewen Susanna , Huang Kexin , Carlson Jeffrey , Sobel Raymond , Zabel Brian 
Published: January 2023

Abstract
Dendritic cells (DC) are versatile immune cells that can promote protective anti-pathogen immunity or dampen destructive autoimmune responses. Fms-like tyrosine kinase 3-ligand (FLT3L) signals through the FLT3 receptor to drive DC differentiation and proliferation. We generated a novel mouse-FLT3L—human-FC-domain (FLT3L-FC) fusion construct that, when combined with hydrodynamic gene delivery (HDT), induces robust DC expansion in vivo. In particular, FLT3L-FC HDT induced expansion of surface marker-defined tolerogenic DC subsets. Given the central role of DC in the pathogenesis of experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis (MS), we investigated the action of FLT3L-FC in EAE. Prophylactic treatment of mice with FLT3L-FC HDT (a single i.v. injection of 10 ug of plasmid DNA) significantly suppressed the onset and clinical severity of EAE, and significantly reduced the number of inflammatory foci in CNS parenchyma. FLT3L-FC HDT in EAE mice induced expansion of peripheral (spleen) and CNS-infiltrating tolerogenic DC, as well as peripheral CD4+ regulatory T cells (Tregs), which we speculate underlies the cellular mechanism of EAE suppression by FLT3L. Our results therefore support the emerging paradigm that the fundamental action of FLT3L in vivo is immune suppression.
Characterization of TCR retrogenic mice that have a YFAK-specific regulatory T cell population. (P5230)
Authors: Ng Sze-Ling , Strominger Jack 
Published: January 2023

Abstract
T cell receptor (TCR) transgenic mice have been instrumental to the understanding of T cell biology. A valuable alternative to transgenic animals is the generation of TCR retrogenic mice using retrovirus-mediated gene transfer of the TCR chains into donor hematopoietic stem cells (HSCs) prior to reconstitution of irradiated recipients. However, to date, these genetically modified mice centered on the cloning and study of TCRs from effector T cells. Here, we isolated several TCRs from a YFAK-specific regulatory T cell (Treg) line in order to study Treg development, function, and maintenance. YFAK is a random amino acid copolymer identified in our lab to be more effective in amelioration of experimental autoimmune encephalomyelitis than the copolymer YEAK (Copaxone), which is currently used in the therapy of human multiple sclerosis. The TCR retrogenic mice generated had successful engraftment of the YFAK-specific Treg population in the thymus. These Tregs were also present in peripheral blood, spleen and lymph nodes. In addition, these cells secreted high levels of anti-inflammatory cytokines. Full characterization of these retrogenic Treg cells will be reported. Thus, the retrovirus-mediated expression of Treg-derived TCR chains in HSCs and transplantation into mice resulted in the in vivo differentiation of these cells into Tregs. This technique has potential in the therapy of autoimmune diseases such as multiple sclerosis by increasing the numbers of Tregs produced.
LEAPS peptide vaccination alters T cell phenotype and suppresses joint inflammation in a murine model of rheumatoid arthitis (P5223)
Authors: Zimmerman Daniel , Mikecz Katalin , Kurko Julia , Glant Tibor , Steiner Harold , Carambula Roy 
Published: January 2023

Abstract
Introduction. A major therapeutic goal in autoimmune inflammatory diseases such as rheumatoid arthritis (RA) is to suppress responses against (auto)antigens present in the target organs. Antigen-specific therapies such as the Ligand Epitope Antigen Presentation System (LEAPS) technology offer such a possibility. Materials and Methods. We evaluated LEAPS therapy in the cartilage proteoglycan (PG) induced arthritis (PGIA) model of RA. After the onset of PGIA, mice were divided in 3 groups, each with a similar mean arthritis index (AI). One group was vaccinated with adjuvant only, and the other groups with one of two LEAPS conjugates of a PG epitope 70 (J-PG70 or derG-PG70) in adjuvant. The same vaccination was repeated two weeks later. AI was measured by visual scoring every other day for 5 weeks. Upon euthanization, the proportions of Th1, Th2, Th17, and regulatory T cells (Tregs) in the spleen were determined by flow cytometry, and PG-specific lymphocyte proliferation by [3H]thymidine uptake. Results. Disease severity (AI) was dramatically suppressed in mice vaccinated with the LEAPS conjugate derG-PG70 as compared with controls or animals receiving J-PG70 vaccine. Protection was associated with reduced PG-specific lymphocyte proliferation, decreased proportions of Th1/Th17 cells, and increases in Th2 cells and Tregs. Conclusion. The derG-PG70 vaccine is therapeutically effective in PGIA (a Th1 dominated disease) by inducing immune deviation in favor of Th2 and Treg cells.
Tregitopes: The active ingredient in IVIG-mediated tolerance induction? (P5224)
Authors: Cousens Leslie , Moise Leonard , Martin William , De Groot Anne 
Published: January 2023

Abstract
In the course of screening IgG sequences for T cell epitopes, we identified Treg epitope peptides, now called Tregitopes, contained in conserved framework regions of Fab and Fc. Tregitopes may provide one explanation for the expansion and stimulation of Treg following intravenous immunoglobulin (IVIg) therapy. Their distinguishing characteristics include in silico signatures of high-affinity binding to multiple human HLA class II DR, and conservation across IgG isotypes as well as mammalian species. Tregitopes induce expansion of CD4+/CD25hi/FoxP3+ T cells and suppress immune responses to co-incubated antigens in vitro. Comparing human Tregitopes (hTregitopes) to murine sequences, we identified class II-restricted murine Tregitope homologs (mTregitopes). We provide evidence that when APCs present Tregitopes to natural (n) Treg, APC expression of MHC II, CD80, and CD86 are decreased. Moreover, Tregitopes increase proportions of IL-10-producing nTreg. We propose the mechanism of Tregitope-mediated tolerance induction to be as follows: 1) APC present Tregitopes to nTreg, 2) nTreg are activated, proliferate and produce IL-10, 3) nTreg provide tolerogenic feedback signals to APC, modulating the APC phenotype, and 4) nTreg and tolerogenic APC together suppress antigen-specific T cell responses. The discovery of Tregitopes in IgG and other autologous proteins may lead to the development of new insights as to the role of Tregs in autoimmune diseases.
Aryl hydrocarbon receptor negatively regulates type I interferon production in murine lupus (P5225)
Authors: Lee Soyoung , Ripley Barry , Millrine David , Chinen Ichino , Kishimoto Tadamitsu 
Published: January 2023

Abstract
Systemic lupus erythematosus is a multi-organ disorder characterized by the production of diverse autoantibodies. Recent studies suggest an important role for type I IFN in the pathogenesis of this disease. Production of type I IFN is induced by the transcription factor IRF7, while type I IFN signaling requires the STAT1 transcription factor. However, it is unclear how type I IFN is negatively regulated. Here, we show that production of type I IFN in cultured pDCs from aryl hydrocarbon receptor knockout mice is significantly higher compared to wild-type mice stimulated with TLR 7/9 agonists. Furthermore, treatment of pDCs from wild-type mice with the aryl hydrocarbon receptor agonist L-kynurenine significantly inhibits TLR 7/9-mediated type I IFN production. We demonstrate that through TLR 7/9 signaling, expression of aryl hydrocarbon receptor is induced, which in-turn forms an inhibitory interaction with IRF7 and STAT1, thus attenuating both type I IFN production and signaling. In addition, we found that production of type I IFN and expression of interferon stimulation genes in aryl hydrocarbon receptor knockout mice is higher than in wild-type mice when we induce lupus-like disease by pristane treatment. Our results suggest that aryl hydrocarbon receptor is a critical negative regulator of TLR-mediated type I IFN production and inhibits type I IFN signaling in murine lupus. We are evaluating protective effects of aryl hydrocarbon receptor agonists in murine lupus.
Novel LMW inhibitors of ITPKb block autoimmune disease by promoting calcium-induced T lymphocyte death (P5165)
Authors: Miller Andrew , Dahlberg Carol , Wen Ben , Sandberg Mark , Beisner Daniel , Parker Albert , Schmedt Christian , Stinson Monique , McPate Mark , Tranter Pamela , Groot-Kormelink Paul , Gosling Martin , Dawson-King Janet , Pan Shifeng , Tian Shin-Shay , Seidel H. Martin , Cooke Michael 
Published: January 2023

Abstract
Lymphocyte antigen receptor-mediated production of Ins(1,4,5)P3 induces the release of Ca2+ from intracellular stores, resulting in the opening of store-operated Ca2+ (SOC) channels. Mice deficient in inositol(1,4,5)P3-3 kinase B (ITPKb), which converts inositol(1,4,5)P3 (IP3) to inositol(1,3,4,5)P4 (IP4), exhibit a complete block in T cell positive selection. Previous studies demonstrated that IP4 is an inhibitor of SOC channels. To understand the role of ITPKb in mature peripheral lymphocytes, inducible ITPKb-/- mice were generated. Deletion of ITPKb in mature lymphocytes reveals that ITPKb is required for mature T cell function and T-dependent antibody responses. Following antigen receptor activation, the loss of ITPKb leads to enhanced Ca2+ levels and the induction of death effector gene expression resulting in apoptosis. We further demonstrate that IP4 is an inhibitor of open-state Orai1 channels. LMW ITPKb inhibitors were identified using a high-throughput compound screen. Application of ITPKb inhibitors to lymphocytes enhanced Ca2+ responses following antigen receptor stimulation, similar to ITPKb-/- cells. Treatment of mice with ITPKb inhibitors recapitulated the block in T cell development observed in ITPKb-/- mice and inhibited antigen-induced arthritis formation in rats. These data identify ITPKb and IP4 as crucial mediators of lymphocyte development and activation, and suggest that inhibition of ITPKb may provide a novel mechanism to treat autoimmune disease.
Anti-idiotypic small molecules neutralize pathogenic anti-ADAMTS13 autoantibodies in autoimmune Thrombotic Thrombocytopenic Purpura in vitro - new treatment tools in vivo? (P5173)
Authors: Schaller Monica , Hiltbrunner Sabine , Sulzer Irmela , Vogel Monique , Kentouche Karim , Laemmle Bernhard , Kremer Hovinga Johanna 
Published: January 2023

Abstract
A therapy aiming at neutralization of inhibitory autoantibodies (Abs) causing autoimmune thrombotic thrombocytopenic purpura (aTTP) would be highly desirable. We screened a large combinatorial small protein library of Designed-Ankryin-Repeat-Protein (DARPins, Molecular Partners AG, Switzerland; library size 1015-23) for anti-idiotypic binders to an equimolar pool of three spleen-derived inhibitory anti-ADAMTS13 monoclonal Abs of two aTTP patients containing 1 of 4 shared CDR3 motifs. Four unique anti-idiotypic DARPins were purified and their neutralization potential tested against 8 spleen-derived anti-ADAMTS13 Abs (200 nM), belonging to the same, shared CDR3 motif used for selection. Anti-idiotypic DARPins restored ADAMTS13 activity up to 100% (2000 nM). By ELISA we found Abs in plasma of 27 of 37 randomly selected aTTP patients that bound specifically to the anti-idiotypic DARPins. Pre-incubation with anti-idiotypic DARPins (960 nM) prevented binding of plasma anti-ADAMTS13 Ab to recombinant ADAMTS13 in a competition ELISA (n=5). Our findings of anti-idiotypic DARPins able to neutralize several, although similar (belonging to the same CDR3 motif) pathogenic anti-ADAMTS13 Abs and the fact that the DARPins are also specifically recognized by plasma-derived anti-ADAMTS13 Abs of different aTTP patients are promising and suggest that possibly only a limited number of the selected DARPins are required to develop a general treatment for aTTP.
Specific targeting of PI 3-kinase p110δ for the treatment of rheumatoid arthritis (P5177)
Authors: Reif Karin , Shen Fang , Wang Yugang , Huang Tao , Lin Zhonghua , Zhang Juan , Suto Eric , Kaplan Charles , Liao Cheng , King Beverly , Nguyen Allen , Yeh Sherry , Delarosa Donnie , Liimatta Marya , Chiu Henry , Sweeney Zachary , Safina Brian , Johnson Adam , DeMartino Julie , DeForge Laura , Salphati Laurent , Lee Wyne , Balazs Mercedesz , Sutherlin Dan 
Published: January 2023

Abstract
The p110δ isoform of PI3K is a therapeutic target for rheumatoid arthritis, but the cellular and molecular mechanisms by which PI3K mediates inflammation are poorly understood. Here we describe a novel highly selective p110δ small molecule inhibitor, G-286, that allowed dissecting the contribution specifically of p110δ to cellular pathways that are implicated in arthritis disease pathogenesis in human and mice. Using G-286, we demonstrate that p110δ regulates B cell- but not myeloid-cell dependent inflammatory arthritis in mice. G-286 blocks B cell receptor dependent proliferation and reduces autoantibody levels in collagen-induced arthritis abrogating disease. However, G-286 does not significantly inhibit FcγR-mediated inflammatory cytokine production in murine macrophages. Accordingly, selective p110δ inhibition did not significantly affect disease progression in FcγR- and myeloid cell-dependent autoantibody-induced arthritis. Importantly, we provide evidence that human and mice diverge in their relative dependency on p110δ to regulate FcγR responses. In addition to B cells and myeloid cells, T cells and osteoclasts contribute to rheumatoid arthritis pathogenesis. Utilizing G-286, we dissect the relative impact of p110δ inhibition on human and mouse T cell and osteoclast function. These results provide new insight in the role of p110δ in arthritis disease processes and offer a compelling rationale for targeting p110δ for the treatment of human rheumatoid arthritis.
Anti-diabetic drug, metformin protects oligodendrocytes under CNS pathological conditions: implication for multiple sclerosis (P5205)
Authors: Paintlia Ajaib , Paintlia Manjeet , Mohan Sarumathi , Singh Avtar , Singh Inderjit 
Published: January 2023

Abstract
We earlier documented that AMPK activators attenuate inflammation in activated mixed glial cultures and autoimmunity in EAE. Recent studies established that AMPK signaling is crucial to protect neurons under CNS pathological conditions however its influence on oligodendrocytes (OLs) loss is unclear. We here demonstrated that the observed loss of OLs as evident from the reduction of cell numbers and decrease in the expression of OL signatory genes in mixed glial cultures stimulated with LPS/IFN-γ was attenuated by AMPK activator (metformin). This effect of metformin was ascribed to the attenuation of inflammatory response and induction of myelinogenic milieu in similarly treated mixed glial cultures via AMPK dependent mechanism. In addition, metformin attenuated oxidative stress and mitochondrial membranal depolarization in immature OLs against cytokine toxicity and enhanced their differentiation into myelin-forming OLs. These in vitro findings were consistent with the attenuation of clinical symptoms, cellular infiltration and myelin loss in EAE animals treated with metformin. In addition, levels of OL-lineage cells signatory genes, neurotrophic factors and MnSOD mRNA transcripts including AMPK phosphorylation were elevated with corresponding reduction of cytokines and chemokines expressions in the CNS similarly treated EAE animals. Together, these data provide evidence that AMPK signaling partcipate in the protection of OLs under CNS pathological conditions.
Transcriptional control of tolerance associated gene TCAIM is CREB, NFATc1 and C/EBPβ dependent resulting in generation of tolerogenic dendritic cells (P2152)
Authors: Panov Ivo , Schlickeiser Stephan , Vogel Simone , Schumann Julia , Schliesser Ulrike , Gossen Manfred , Berberich-Siebelt Friederike , Sawitzki Birgit 
Published: January 2023

Abstract
Cell therapy by tolerogenic dendritic cells has become an attractive therapeutic option in transplantation. We could recently show that high expression of TCAIM, formerly known as TOAG-1, in dendritic cells (DCs) is associated with stable tolerance following transplantation. Here, we investigated transcriptional control of TCAIM in murine bone marrow derived DCs (BMDCs) and human MUTZ-3 derived DCs (M3DCs). We have cloned the human TCAIM promoter to identify regulatory elements by site directed mutagenesis. In addition, we performed luciferase reporter as well as ChIP assays. Furthermore, BMDCs or M3DCs were pre-incubated with cAMP elevating drugs prior to LPS-mediated maturation. Phenotype and tolerogenic potential of DCs were investigated by qPCR, flow cytometry, CBA and MLR. Site-directed mutagenesis, reporter assays and ChIP defined TCAIM core promoter containing three CREB responsive elements. Co-transfections revealed positive regulation of promoter activity by NFATc1 and C/EBPβ. Furthermore, pre-incubation of M3DCs or BMDCs with cAMP elevating drugs leading to CREB activation resulted in high TCAIM expression, inhibited DC maturation, diminished pro-inflammatory cytokine release and induced high frequency of CD4+CD25+FoxP3+ Tregs in DC-T cell co-cultures. These results indicate that transcriptional activation of TCAIM is cAMP/CREB dependent and further amplified by NFATc1 and C/EBPβ, resulting in induction of tolerogenic potential in human M3DCs and murine BMDCs.
Sodium cromoglycate treatment of CD200R1KO.CD200tg mice enhances graft survival (P2154)
Authors: Gorczynski Reg , Chen Zhiqi , Yu Kai 
Published: January 2023

Abstract
Allograft survival is not increased in CD200R1KO mice, lacking the primary inhibitor receptor for CD200, unlike in CD200tg mice. Rejection in both control, and CD200R1KO mice is associated with graft infiltration by activated mast cells, with evidence for degranulation (&gt;80%). There is evidence that alternate CD200Rs in mice can contribute to immunosuppression through altered dendritic cell differentiation, and enhanced induction of Foxp3+Tregs. We asked whether, in CD200R1KO.CD200tg mice, attenuation of mast cell degranulation by sodium cromoglycate could foster enhanced graft survival following induction of Tregs. BALB/c skin grafts were transplanted to 10/group control, CD200tg or CD200R1KO.CD200tg mice, with/without treatment with cromoglycate (150mg/Kg, alternate days). All animals received low-dose rapamycin (0.5mg/Kg), previously shown to prolong survival only in CD200tg mice. Graft survival was monitored daily from d10, and splenic MLC responses measured in vitro on d14/21. Immunohistology was performed on all grafted tissue at d14. Graft survival was increased only in CD200tg mice, and in CD200R1KO.CD200tg mice receiving cromoglycate (p&lt;0.05). This was accompanied by decreased degranulation of graft-infiltrating mast cells, and increased Foxp3+Treg infiltration. Survival was abolished by ongoing infusion of neutralizing anti-CD200 mAb, or infusion of anti-CD200R1/2mAb (in CD200tg or CD200R1KO.CD200tg mice respectively).
Prostaglandin E2-induced changes in alveolar macrophage scavenger receptor profiles alter phagocytosis of bacteria post-bone marrow transplantation (P2156)
Authors: Domingo-Gonzalez Racquel , Katz Samuel , Serezani C. Henrique , Moore Thomas , LeVine Ann Marie , Moore Bethany 
Published: January 2023

Abstract
The effectiveness of hematopoietic stem cell transplantation as a therapy is complicated by pulmonary infections. Using our syngeneic bone marrow transplant (BMT) mouse model, BMT mice displayed increased susceptibility to Pseudomonas aeruginosa and Staphylococcus aureus. BMT alveolar macrophages (AMs) exhibited a defect in P. aeruginosa phagocytosis while S. aureus uptake was enhanced. This difference was due to an altered scavenger receptor (SR) profile. Interestingly, MARCO expression was decreased while SR-AI/II was increased. Phagocytosis assays with SR-AI/II transfected-CHO cells revealed SR-AI/II was important for S. aureus uptake but not P. aeruginosa. Conversely, AMs treated in vitro with soluble MARCO exhibited similar defects in P. aeruginosa internalization as did BMT AMs. miR-155 targets the 3’UTR of SR-AI, however, its expression is decreased post-BMT. Anti-miR-155-transfected AMs exhibited an increase in SR-AI/II expression and S. aureus phagocytosis. In vitro treatment of AMs with prostaglandin E2 (PGE2) (elevated post-BMT) increased SR-AI/II, and decreased MARCO and miR-155. Despite a difference in phagocytosis, BMT AMs harbor a killing defect to both P. aeruginosa and S. aureus. Thus, our data suggest that PGE2-driven alterations in SR and miR-155 expression account for the differential phagocytosis of P. aeruginosa and S. aureus but impaired killing ultimately confers increased susceptibility to pulmonary infection.
Surfactant protein A regulation of host defense post-bone marrow transplantation (P2158)
Authors: Ashley Shanna , Domingo-Gonzalez Racquel , Wilke Carol , Agarwal Manisha , Levine Ann Marie , Moore Bethany 
Published: January 2023

Abstract
Patients who undergo stem cell transplant are at increased risk of developing bacterial lung infections. We have developed a murine model of syngeneic bone marrow transplant to try to understand the mechanisms which may be responsible for impaired innate immunity post-transplant. Our results demonstrate that syngeneic BMT mice are more susceptible to Pseudomonas aeruginosa post-transplant. This is mediated in part by reduced expression of the MARCO scavenger receptor. We now report that the BMT mice are also deficient in the production of surfactant protein A post-BMT. Levels of SpA in the bronchoalveolar lavage fluid are diminished post-BMT. Phagocytosis assays demonstrate that phagocytosis of Pseudomonas aeruginosa can be enhanced in the presence of exogenous SpA. We have evidence to suggest that exogenous SpA allows Pseudomonas aeruginosa to be phagocytosed by binding to the scavenger receptor A (SRA) I/II. Current studies are underway to determine why SpA is reduced post-BMT and to determine the influence of SpA on bacterial killing post-BMT.