bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of peritoneal B-1a cells in spontaneous and induced autoimmune hemolytic anemia. (P4038)
Authors: Scatizzi John , Theofilopoulos Argyrios , Kono Dwight 
Published: January 2023

Abstract
Previous studies have suggested peritoneal B-1a cells play a vital role in the development of anti-erythrocyte antibodies (AEA), but this remains controversial. While studying the Lbw2 lupus-susceptibility locus on chr 4, we discovered a subcongenic line, Lbw2-SE (NZB strain with 20 Mb NZW), that was deficient in peritoneal B-1a cells. NZB mice spontaneously develop autoimmune hemolytic anemia (AIHA) and exhibit an expansion of peritoneal B-1a cells, therefore we used this congenic to study the role of B-1a B cells in AEA production. Compared to NZB, Lbw2-SE mice had decreased total number of peritoneal B cell subsets (B-1a, B-1b, and B-2) but no differences in the number of splenic B cell subsets and a slight delay in AEA incidence similar to Lbw-2 congenics. To precisely map the B-1a-affecting variant, additional subcongenics were generated of which two (SEA & SED) had the low B1a phenotype. They, however, did not overlap suggesting the responsible mutation was located outside of the Lbw2-SE interval. The SEA and SED sublines had AIHA similar to NZB mice, while the SEB and SEC sublines had normal numbers of B-1a cells yet lower incidences of AIHA. Interestingly, after administering a TLR3 agonist to induce AEAs in young mice, the SEA and SED sublines with fewer B-1a cells demonstrated resistance to the development of AEAs. Our data indicate that B-1a cells are not required for the development of AEAs, but can enhance induction of AIHA under environmental conditions.
Autoantibody induction by DNA-containing immune complexes requires HMGB1 with TLR2/miR-155 pathway (P4040)
Authors: Xiong Sidong , Wen Zhenke , Xu Wei 
Published: January 2023

Abstract
Anti-dsDNA autoantibody has been reported as a central pathogenic factor of SLE. However, the mechanisms of anti-dsDNA antibody production still remain unclear. Recent evidence indicates that circulating DNA-containing immune complexes, one of the hallmarks of SLE, might be involved in the autoantibody production. Here we mainly explored the potential role and underlying mechanisms of DNA-containing immune complexes in the anti-dsDNA antibody production. We found that these immune complexes provoked anti-dsDNA antibody production primarily through their HMGB1 component, whose level was highly and positively correlated with the anti-dsDNA antibody level in SLE patients. Furthermore, the HMGB1-mediated autoantibody production was in a TLR2/MyD88 dependent pattern, and modulated by the miR-155 via targeting Ets-1. Our results firstly reported the crucial role of HMGB1 component of DNA-containing immune complexes in the autoantibody production, which was mediated and regulated by TLR2/MyD88/miR-155/Ets-1 pathways. These findings may provide novel mechanistic insight into the persistent anti-dsDNA antibody production and new clues for the development of therapeutic strategies for SLE.
NF-κB inducing kinase as a key player in regulating autoreactive B cell maturation (P4048)
Authors: Lee Sang-Ryul , Ramsdell Clifton , McCray Suzanne , Diz Ramiro , Clarke Stephen 
Published: January 2023

Abstract
The regulation of autoreactive B cells is crucial in immune systems to prevent developing autoimmune diseases in human and animal models. A critical peripheral B cell tolerance mechanism is exclusion of autoreactive B cells from the mature repertoire due to a failure to compete with non-autoreactive B cells. B cell activation factor (Baff) is one of the most important factors to discriminate autoreactive and non-autoreactive B cells in periphery. Therefore, the level of Baff expression in vivo is significant, since excess Baff can override exclusion and lead to autoimmunity, and may contribute to some human autoimmune diseases. We show here using B cells with different affinities for Sm, a self-antigen targeted in systemic lupus erythematosus (SLE), that the Baff-induced level of NF-κB inducing kinase (NIK) is reduced commensurate with the affinity for Sm and independently of Baffr levels. Reduced NIK differentially affect downstream signaling pathways, proportionally decreasing Akt activation and its repertoire inclusion function, but leaving intact NF-κB2 activation and its survival function. Thus, NIK functions as a key player to regulate entry into the mature B cell repertoire and preferentially excluding autoreactive B cells.
Potent therapeutic activity of a novel Salmonella-based cancer vaccine (P4314)
Authors: Xu Xin , Hegazy Wael , Gao Xiuhua , Guo Linjie , Courtney Amy , Kurbanov Suhrab , Hensel Micheal , Metelitsa Leonid 
Published: January 2023

Abstract
Inadequate antigen delivery and insufficient activation of innate immunity are among major factors responsible for the failure of cancer vaccines. We recently reported a new type of an attenuated Salmonella-based oral vaccine that uses the evolutionary conserved SPI2 locus-encoded molecular machinery of Salmonella to express and translocate survivin into the cytosol of antigen-presenting cells. In order to maximize the vaccine therapeutic potential, we tested a series of SPI2 promoter/effector combinations, performed codon optimization of survivin cDNA, and used a synthetic NKT-cell ligand, 7WD8-5 as an adjuvant. We found the combination of sifB promoter with sseJ effector could enhance vaccine immunogenicity 5 fold that resulted in a much stronger antitumor activity in A20 murine lymphoma model compared with the original vaccine. The vaccine therapeutic efficacy was further enhanced by combination with 7WD8-5, resulting in complete tumor regression. The improved vaccine was also effective against established CT26 colon carcinoma tumors. Antibody depletion experiments demonstrated that the anti-tumor activity depends on both CD8 and CD4 T cells, but not NK cells. Importantly, we were able to visualize tumor infiltration with CD8 T cells that accompanied tumor regression. Therefore, antigen delivery via SPI2-regulated secretion system of Salmonella may serve as a foundation for effective cancer vaccines.
Vascular endothelial growth factor expression is associated with B cell activating factor production stimulated with tumor necrosis factor-α in MH7A human synovial cells (P6280)
Authors: Moon Eun Yi , Lee Geun-Hee , Lee Jae-Wook , Lee Jiyoung , Yang Donghee , Go Ahreum 
Published: January 2023

Abstract
Rheumatoid arthritis (RA), one of autoimmune diseases, is characterized by histological hallmarks such as hyperplasia of the synovial lining cells, mononuclear cell infiltration, angiogenesis, and osteoclastic bone destruction. Angiogenesis is mediated through expression of vascular endothelial growth factor (VEGF) in RA synovium. VEGF expression is enhanced by TNF-α, the main pro-inflammatory cytokine in RA. B cell activating factor (BAFF) which plays a role in maturation and maintenance of B cells is also associated with autoimmune RA. Here, we investigated whether BAFF could regulate VEGF expression in MH7A synovial cells that is established by transfection with the SV40 T antigen (Miyazawa et al., 1998). When MH7A cells were treated with TNF-α, data showed that TNF-α increased the expression of BAFF and VEGF as judged by western blotting, RT-PCR and luciferase promoter assay. Inhibition of BAFF expression with BAFF-siRNA decreased VEGF expression. In addition, BAFF and VEGF expression was mediated by nuclear translocation of c-Fos activated by the treatment with TNF-α as judged by the transfection of MH7A cells with c-fos-siRNA. In conclusion, our results suggest for the first time that angiogenesis in RA could be controlled by BAFF-mediated VEGF expression.
Bcr/Abl-induced deregulation of the IL-33/ST2 pathway in CD34(+) progenitors from chronic myeloid leukemia patients (P6284)
Authors: Gombert Jean-Marc , Levescot Anaïs , Flamant Stéphane , Jacomet Florence , Basbous Sara , Féraud Olivier , Bonnet Marie-Laure , Giraud Christine , Roy Lydia , Barra Anne , Turhan Ali , Guilhot François , Herbelin André 
Published: January 2023

Abstract
Although it is generally acknowledged that cytokines regulate normal hematopoiesis in an autocrine/paracrine fashion, their possible role in chronic myeloid leukemia (CML) and resistance to imatinib mesylate (IM) treatment remain poorly investigated. Here, we report that CD34(+) progenitors from CML patients at diagnosis are selectively targeted by the cytokine/alarmin IL-33. Indeed, CML CD34(+) progenitors up-regulate their cell surface expression of the IL-33-specific receptor chain ST2, proliferate and produce cytokines in response to IL-33, conversely to CD34(+) cells from healthy individuals. Moreover, ST2 overexpression is normalized following IM therapy, while IL-33 counteracts in-vitro IM-induced growth arrest in CML CD34(+) progenitors via re-activation of the STAT5 pathway. Clinically, CML is associated with high circulating levels of soluble ST2, commonly used as a functional signature of IL-33 signaling in vivo. Taken together, our results support the hypothesis that the IL-33/ST2 pathway facilitates Bcr/Abl-induced leukemogenesis and contributes to IM resistance in CML patients.
Antigen-specific Treg and IL-10 influence DC immunogenicity hours following vaccination with a self versus a foreign antigen (P4232)
Authors: Marvel Douglas , Finn Olivera 
Published: January 2023

Abstract
Mice transgenic for the human tumor antigen MUC1 (MUC1.Tg) are hyporesponsive to MUC1 peptide relative to WT mice. A recently identified biomarker of this hyporesponsiveness is suppression in splenic dendritic cells (DC) of a family of pancreatic enzymes, represented by several trypsin isoforms and carboxypeptidase B1. These enzymes are upregulated following vaccination of WT mice with MUC1 peptide (foreign antigen) or MUC1.Tg mice with ovalbumin (foreign antigen), but are suppressed following vaccination of MUC1.Tg mice with MUC1 peptide (self antigen). This suppression can be alleviated by eliminating Tregs or by blocking signaling through the IL-10 receptor. This enzyme profile marking suppression or activation of DC could be identified as early as 4 hours post MUC1 peptide vaccination of WT and MUC1.Tg mice. Differences in enzyme expression also correlated with differential NK cell activation at the same early timepoint as measured by IFNγ and IL-10 secretion. This work shows that the decision for tolerance or immunity is established in multiple cell types no more than 4 hours post vaccination and that these enzymes are an early biomarker of this decision.
Pharmacological calcium mobilization synergizes with TLR signaling to enhance IL-12 production by murine DC (P4238)
Authors: Huang Chi , Berk Erik , Xu Min , Czerniecki Brian , Koski Gary 
Published: January 2023

Abstract
A critical DC-produced factor for polarizing Th1 immunity is the heterodimeric cytokine IL-12. Although IL-12 production can be triggered by stimulation of DC with single Toll-like receptor (TLR) ligands, optimized production requires that multiple signals be delivered to the DC. These include dual TLR ligands, single TLR ligands paired with the cytokine interferon-gamma or CD40L combined with these other signals. Although calcium mobilizing signals have been shown to induce phenotypical maturation of DCs, they have never been shown to synergize with TLR or cytokine signals to enhance IL-12 production. Murine bone marrow-derived DCs pretreated with calcium ionophore 4 hours prior to TLR ligand exposure significantly enhance IL-12 p70 production by DCs. Thapsigargin, a compound that enhances intracellular calcium levels by a different mechanism, had similar effects. The drugs cyclosporine A and ascomycin, which antagonize the activity of the calcium-dependent serine-threonine phosphatase, calcineurin, suppressed the IL-12-enhancing activity of calcium mobilization. When mouse T cells were co-cultured with allogeneic DCs activated with calcium ionophore, TLR ligands, or both, paired activation stimulation induced DCs with superior T cell stimulatory capacity as measured by IFN-gamma output (ELISA), and proliferation measured by CFSE dilution. Calcium mobilization may therefore provide a method for superior activation of Th1-polarizing DCs for clinical testing.
Antigen-specific tolerance induction by Tregitopes in vivo (P4202)
Authors: De Groot Anne , Cousens Leslie , Moise Leonard , Najafian Nader , Mingozzi Federico , Elyaman Wassim , Mazer Bruce , Khoury Samia , Su Yan , Scott David , Martin William 
Published: January 2023

Abstract
Modulation of T cell responses provide of new opportunities in the treatment of autoimmune and inflammatory diseases. Tregitopes are regulatory T cell (Treg) epitopes found in IgG that provide beneficial immunomodulatory effects, paralleling effects attributed to IVIG. In this presentation, we will provide evidence that Tregitopes derived from human IgG can reproduce immunomodulatory effects of IVIG in vitro and in vivo. Tregitopes cause CD4+CD25+FoxP3+ Treg to expand and produce IL-10 in vitro, and iTreg are induced in vivo. Induction and functions of Tregs have been examined in in vivo model systems such as D011.10 TCR transgenic mice, transplant of BM12 to C57BL/6, AAV-mediated gene transfer and EAE. Together, the data show that effector T cells, Th17, and Th9 cells are modified in the presence of Tregitopes. In OVA-induced allergic airway disease, we observed significant and reproducible expansion of Tregs in conjunction with decreased airway reactivity comparable to, if not greater than IVIG. We will provide additional unpublished evidence demonstrating the antigen specificity of tolerance induction using Tregitopes in conjunction with target antigens, and discuss the relevance of Tregitopes to the treatment of human immune-mediated diseases. Additionally, Treg epitopes (Tregitopes?) have been identified in other common serum proteins, suggesting that peripheral control of inflammatory signals may in part be due to intrinsic self-protein “off switches".
CD45RB ligation ameliorates experimental colitis by inducing Tregs and inhibiting inflammatory Teff cells (P4206)
Authors: Lin Yan , Froicu Monica , Rothstein David 
Published: January 2023

Abstract
In wt mice, α-CD45RB (MB23G2) treatment expands Tregs by both inducing iTregs and by enhancing homeostatic proliferation of nTregs. We examined the effect of α-CD45RB in a cell transfer model of colitis. Transfer of 3X105 CD4+Foxp3-CD45RBHi (Tconv) cells from Foxp3-reporter mice into Rag-/- mice resulted in severe colitis with 20% wt loss by 8 wks. α-CD45RB treatment (100ug; d0, 1) had no effect on number of Tconv but increased iTreg ≥ 2X in mesenteric LN (MLN), spleen, and colonic tissue. This completely prevented wt loss and decreased colitis score (at 8 wks) by 25% vs. Tconv cells alone (p&lt;.05). While transfer of subtherapeutic (104) nTreg had no effect on colitis induced by Tconv, adding a-CD45RB prevented wt loss, further cut the colitis score by 50%, and increased Treg ~2.5X. To confirm the role of Tregs, Tconv were transferred from Foxp3-DTR mice and iTregs eliminated with diphtheria toxin. In this setting α-CD45RB still delayed onset of colitis, although all mice began losing wt by 3 wks (and there was no survival benefit). In this setting, delayed colitis by α-CD45RB was associated with a 2X decrease in IFNγ expression by Teff in MLN, whereas IL-17 was unchanged. These data demonstrate that α-CD45RB can uniquely ameliorate colitis by inducing iTreg or by expanding nTregs, and also inhibits colonic inflammation by Teff cells, possibly by inhibiting IFNγ.
Protection by a broadly neutralizing monoclonal antibody to pandemic Influenza requires selective Fc receptor engagement (P4216)
Authors: DiLillo David , Tan Gene , Palese Peter , Ravetch Jeffrey 
Published: January 2023

Abstract
Neutralizing Abs against influenza viruses have traditionally been thought to provide protection by interfering with virus entry and/or fusion with host cells, events that rely solely on Ab variable region binding to viral spike proteins. However, the contributions of in vivo mechanisms conferred by Fc-Fc receptor (FcγR) interactions during protection by Ab remain unclear. We assessed the role of FcγRs during influenza virus neutralization in mice using mAbs directed to the HA antigen. We found that a broadly neutralizing mAb (bNAb) targeting the conserved stem region of HA confers protection to mice from lethal viral challenge, and required Fc-FcγR interactions for in vivo activity against both laboratory virus strains as well as the 2009 pandemic H1N1 virus. By contrast, a strain-specific mAb to the variable head domain of HA was equally protective both in the presence or absence of FcγR interactions. We then generated a chimeric human IgG1 Fc version of the anti-stem bNAb, modified to selectively enhance human activating FcγR engagement. We utilized FcγR-humanized mice, which express all human FcγRs on a genetic background lacking mouse FcγRs, to demonstrate augmented protection by the modified bNAb compared to wild type bNAb. Thus, Fc-FcγR interactions are required for bNAb-mediated protection and can be manipulated for optimal protection in vivo. These findings represent a general approach towards enhancing bNAb-mediated protection and warrant clinical investigation.
Monitoring the evolution of antigen-specific antibodies in circulation and their corresponding B cell clones in longitudinal immunization case studies through the use of NG-XMT (P4186)
Authors: Darce Jaime , Lutz Stephen , Schieferl Sandra , Moreno Elizabeth , Ramenani Ravi , Wieler James , Popova Lana , Beaudet Jason , Zhang Xiaowu , Sato Shuji , Beausoleil Sean , Polakiewicz Roberto , Cheung Wan 
Published: January 2023

Abstract
Previous studies aimed at determining the affinity maturation pathways of monoclonal antibodies during an immunization have relied on comparing germ-line with mature forms of antibodies present in either transgenic B cell receptor mouse models or by cloning circulating human B cells present in peripheral blood (PB) of pre and post-immunized individuals. These approaches have been insightful, but they do not identify in confidence the true B cell clone(s) producing the antigen-specific antibodies found in the sera of immunized animals or humans. We recently developed a technology, NG-XMTTM, encompassing tandem mass spectrometry and next generation sequencing1,2, which for the first time enables the 1) identification of the anatomical location of the B cell clone(s) corresponding to the antigen-specific serum antibodies 2) investigation of clonal diversity of antigen-specific B cell clones residing in primary and secondary lymphoid organs and circulating in PB and 3) analysis of the evolving affinity mature serum antibodies, in two longitudinal immunization studies of rabbits and humans. These results not only advance our understanding of the affinity maturation process and the dynamics of memory B cells and plasma cell development that occurs during an immunization response, they also allow us to use this information to generate useful recombinant antibodies that can be utilized in passive immunization strategies. 1Nat Biotechnol. 2012,30:447; 2Nat Biotechnol. 2012,30:1039
In vitro and in vivo pharmacological assessment of a targeted plasmid gene containing immunotoxin, DT390-IL-18-SRα on suppression of immunopathology in mice experimentally infected with Shistosoma mansoni (P4192)
Authors: Al harbi Naif , Bahashwan Saleh 
Published: January 2023

Abstract
Purpose: To evaluate both in vitro and in vivo effects of DT390-IL-18-SRα immunotoxoin on the development of liver immunopathology in murine schistosomiasis mansoni. Methods: The antiproliferative effect and in vitro granuloma formation (IVGF) inhibition were evaluated using methyl thaiazolyl tetrazolium and IVGF index respectively. In vivo evaluation, mice were divided into four groups of twelve mice each: Group1 normal non infected (-ve control), Group 2, 3 and 4 were infected percutaneously with 25 cercariae. After 6 weeks post infection, Group2 was treated with PBS (+ve control), Group3 was treated with plasmid DNA (50 µg) embedded with cationic liposome in 50 µl PBS, injected intramuscular in the hind limbs once daily for two weeks and Group4 was treated with DT390-SRα (mutant control). After animals sacrification, liver was removed for histopathological studies. Results: DT390-IL-18-SRα showed suppression of spleen lymphocytes proliferation and IVGF in a dose dependant manner as well as suppression of liver granulomas size by 80%, while mutant toxin had no significant suppression. Conclusion: The immunotoxin showed selective toxicity to antigen activated lymphocytes in vitro with reduced clinical and pathological severities of the disease.
Effects of sublingual immunotherapy on a murine model of Japanese cedar pollinosis (P4198)
Authors: Azuma Miyuki , Zhang Chenyang , Yanagisawa Shohei , Tomoda Taketo , Kang Siwen , Ohno Tatsukuni 
Published: January 2023

Abstract
Japanese cedar (Cryptomeria japonica) pollinosis (JCP) is one of the most common allergic diseases in Japan. Sublingual immunotherapy (SLIT) has been performed as a safer and more beneficial treatment to induce allergen-specific immune tolerance. However, immunological mechanisms and therapeutic biomarkers for SLIT remain unclear. In this study, we have established a new murine model of JCP that resembles human JCP with crude pollen grains and without the use of adjuvant and examined the effects of SLIT. SLIT was performed by the graded doses of cedar pollen extract painting onto the ventral surface of tongue for 28 days. [Results] The frequency of sneezing and the duration of rubbing for 10 min after the final challenge, serum IgE titer, pollen-specific IgG1, and the ratio of eosinophils in BALF and nasal mucosae were significantly elevated in the pollinosis mice. SLIT efficiently reduced the above manifestations. SLIT significantly decreased pollen-specific IL-4, IL-5, IL-13 and IL-10 production by splenic T cells and DC activation status such as MHC class II, CD86, and B7-H1 expression in the regional lymph nodes. Histological examination revealed that repeated pollen extract painting onto the sublingual mucosae replaced sublingual resident DCs with newly recruited CD11b+ DCs. These results suggest that our new pollinosis model is beneficial to evaluate and develop a new immunotherapy and therapeutic biomarkers.
CD4 T regulatory cells (Treg) control CD8 T cell responses to human herpesvirus 8 (HHV-8) lytic and latency proteins (P6056)
Authors: Lepone Lauren , Rappocciolo Giovanna , Knowlton Emilee , Jenkins Frank , Rinaldo Charles 
Published: January 2023

Abstract
Although CD8 T cells are considered important in controlling HHV-8 (aka KSHV) infection, the etiologic agent of Kaposi’s sarcoma (KS), there is little evidence to support this. Moreover, these T cell responses are relatively non-robust, suggesting that they are under tight regulatory control. We conducted a comprehensive, non-concurrent prospective study of the effect of Treg on CD8 T cell reactivity to HHV-8 lytic and latency proteins in HHV-8 monoinfected, healthy subjects compared to untreated, HHV-8/HIV-1 coinfected subjects who did and did not develop KS in the Multicenter AIDS Cohort Study. Direct staining of PBMC with MHCI multimers showed a relatively high frequency of HHV-8 antigen-specific CD8 T cells compared to low functional T cell activity (IFN-γ ELISPOT) in response to HHV-8 lytic and latency proteins and HIV-1 Gag beginning many years prior to development of KS. Removal of Treg enhanced HHV-8 specific, IFN-γ production by CD8 T cells, with or without HIV-1 coinfection and KS. These data show that beginning very early in HHV-8/HIV-1 coinfection, low antiviral T cell responses are related to eventual development of KS. Moreover, Treg suppress CD8 T cell responses to HHV-8 antigens, effectively masking more robust, underlying anti-HHV-8 T cell responses. The involvement of CD8 T cells and Treg in control of HHV-8 infection has important implications for understanding HHV-8 immunopathogenesis and development of vaccines to prevent KS.