bluuebunny/crossref_metadata_2025_split huggingface dataset:
NALP3 regulates NALT B220+ cell-responses to ricin toxoid and induction of secretory IgA Abs (P3194)
Authors: Jee Junbae , Bonnegarde-Bernard Astrid , Remy Lauriane , Steiner Haley , Fial Michael , Boyaka Prosper 
Published: January 2023

Abstract
Secretory IgA (SIgA) Abs play an important role in the protection of mucosal surfaces including the respiratory tract. Several bacterial toxin and derivatives were shown to act as adjuvants and promote SIgA responses to co-administered antigens, but little is known about potential of plant toxins and derivatives to induce SIgA Abs. We found that chemically inactivated ricin toxoid (RT) increases the frequencies of CD11b+phospho-p65 NF-κB+ cells in nasopharyngeal-associated lymphoid tissues (NALT), an effect associated with increased expression of CD40 molecules on CD11b+ macrophages and enhanced pro-inflammatory cytokine responses. Three hours after intranasal administration of RT in vivo, NALT tissues showed a significant increase in the percentage of B220+ cells, which appeared to undergo rapid proliferation. When nasally co-administered with an unrelated antigen, RT induced broad antigen-specific T helper cell-cytokine responses and promoted antigen-specific SIgA Abs. This adjuvant effect of RT was altered in NALP3 KO mice, which exhibited lower number of B cells in NALT after intranasal administration of RT. Furthermore, antigen-specific T cell and B cell responses, as well as antigen-specific SIgA Ab responses were diminished significantly in NALP3 KO mice. Our results show that the plant toxin derivative RT is a mucosal adjuvant, which promotes SIgA via B cell-recruitment and activation in NALT tissues, and that NALP3 is a key regulator of this activity.
Genital chlamydia trachomatis infection associated immune responses alter host microRNAs expression (P3196)
Authors: Gupta Rishein , Arkatkar Tanvi , Yu JiehJuen , Wali Shradha , Chambers James , Guentzel Neal , Arulanandam Bernard 
Published: January 2023

Abstract
Chlamydia trachomatis (CT) is the leading cause of human bacterial sexually transmitted infections and associated reproductive damage. Given the involvement of microRNAs (miRs) as immune regulators and that TLR2 and CD4+ T cells are associated with host defenses and clearance of CT, we analyzed the modulation of miRs in genital tracts (GT) following CT challenge of wild type (WT), TLR2 deficient (TLR2-/-) and CD4+ deficient (CD4-/-) C57BL/6 mice. CT elementary bodies (5X104 IFU) were inoculated intravaginally for analysis at days 6 (early infection) and 12 (established infection). GT were removed and divided into lower (LGT; vagina & cervix), and upper (UGT) regions for RNA extraction and immunopathology associated miR PCR analyses. Within the WT LGT at day 6, miRs significantly down-regulated were mir-125b-5p (-17.34 fold change), miR-16(-8.87), mir-214(-4.30), mir-182(-19.29), and miR-30c(-19.15) while miR-135a(+13.89) was significantly upregulated, profiles not exhibited by day 12 in LGT and UGT. Moreover, we found significant differences in regulation of miR-214(-3.45) and miR-125b-5p(+1.85) in TLR2-/- GT and miR-214(-2.20) and miR-135a(-2.46) in CD4-/- GT compared to WT mice. Of importance, in vitro knockdown analyses with specific inhibitors of these miRs resulted in 30-45% increase in CT infectivity. Overall, this first report provides for further investigation on contribution of host miRs in CT ascension, associated inflammation and reproductive pathology.
Recognition of soluble yeast β-1,3/1,6 glucan by complement receptor 1 is essential for it to bind complement receptor 3 on human neutrophils and monocytes, and complement receptor 2 on B cells (P3048)
Authors: Bose Nandita , Chan Anissa , Bykowski Jonas Adria , Qiu Xiaohong , Grossman William 
Published: January 2023

Abstract
β-glucans are considered as fungal pathogen-associated molecular patterns that are recognized by innate human cells. Our previous studies demonstrated that Imprime PGG®, an analytically well-characterized form of yeast-derived soluble β−glucan, bound to human neutrophils and monocytes via complement receptor 3 (CR3) and B-cells via CR2, and that receptor binding was complement-dependent. The objective of this study was to further our understanding of the mechanism underlying the interaction of soluble β−glucan with immune cells, specifically, to investigate a role for complement receptor type 1 (CR1; CD35; C3b/C4b receptor) in the binding of Imprime PGG. Blocking of CR1 by anti-CR1 monoclonal antibody significantly abrogated binding of Imprime PGG on all three cell types. Cell-surface CR1, as opposed to soluble CR1, was shown to be more important in mediating Imprime PGG binding. The role of CR1 was further confirmed by demonstrating enhanced binding of Imprime PGG to HEK 293T cells transfected with a combination of CR1 and CR2 genes in comparison to either gene alone. These results suggest that CR1 receptor works in concert with CR3 on neutrophils and monocytes, and with CR2 on B cells in recognizing Imprime PGG. Modulation of Imprime PGG-mediated immune functions after blocking CR1 receptor will also be presented. These data demonstrate for the first time the interplay of several complement receptors in recognizing soluble β−glucan by human immune cells.
Inhibition of Cryptococcus neoformans-mediated phagolysosome damage by induced lysosomal renitence constrains fungal growth. (P3106)
Authors: Olszewski Michal , Davis Michael , Yafeng Qiu , Chapman Rebekah , Malachowski Antoni , Vedula Priya , Swanson Joel 
Published: January 2023

Abstract
Cryptococcus neoformans (C.neo) is a pathogenic yeast which primarily infects the lungs. The mechanisms which enable intracellular replication in unactivated macrophages by C.neo and the strategies employed by classically activated macrophages to combat this replication are incompletely understood. In this work we explore lysosomal damage as an important intracellular survival strategy of C.neo. We measured lysosome damage in C.neo infected murine bone marrow-derived macrophages using ratiometric-epifluorescence microscopy. C.neo growth inhibition data were confirmed by in vitro growth assay. C.neo-mediated lysosome damage was observed in a significant portion of the infected macrophages. The damage increased in frequency and average magnitude with time and replication of the intracellular yeast. Lysosome damage was significantly reduced in macrophages which had phagocytosed heat killed C.neo. Increased lysosome damage correlated with increased C.neo replication and reduced yeast killing. Finally, macrophage activation with IFN-γ but not IL-4 protected macrophages from lysosome damage and promoted increased killing of C.neo. Thus, we conclude that Lysosome damage may be important to the C.neo survival strategy in the host and that classically-activated host macrophages counter this strategy by inducing lysosome renitence. Thus, therapeutic strategies which decrease the ability of C.neo to cause lysosomal damage may be valuable in treating these infections.
Immunologically active cryogels for breast cancer therapy (P4329)
Authors: Bencherif Sidi , Draganov Dobrin , Lewin Sarah , Li Aileen , Sands Roger , Verbeke Catia , Dranoff Glenn , Mooney David 
Published: January 2023

Abstract
Passive immunotherapy has become an effective adjunct for the treatment of HER2/neu-overexpressing breast cancers, as patients can respond well to monoclonal antibodies such as trastuzumab (anti-HER-2/neu antibody therapy). However, patients with late-stage disease, who often become immunosuppressed are unlikely to respond, motivating the development of new prophylactic vaccines. To this end, we have developed an injectable, polymer-based cryogel vaccine containing living, attenuated HER-2/neu-overexpressing breast cancer cells. The cryogel-based vaccine mimics key aspects of bacterial infection and directly controls immune-cell trafficking and activation in the body. This system provides a sustained release of GM-CSF to recruit host dendritic cells (DCs) to the porous material, and subsequently presents breast cancer antigens and TLR9 ligand CpG oligonucleotides to activate the resident DCs. Subcutaneous injection of the cryogel vaccines provide potent prophylactic protection against mammary cancer in mice, consistent with significantly higher titers of Her-2/neu-specific antibodies compared to the humoral responses induced by bolus injection of irradiated GM-CSF-secreting breast tumor cells. The cryogel-based vaccines induced a 70-fold increase in antibody production compared to untreated mice and 100% survival was achieved in vaccinated mice. The cryogel-based vaccines represent a promising tool for the development of novel active immunotherapeutic approaches to cancer.
Synergistic induction of anti-tumour immunity by co-delivery of protein and α-galactosylceramide on exosomes (P4457)
Authors: Gehrmann Ulf , Hiltbrunner Stefanie , Georgoudaki Anna-Maria , Karlsson Mikael C. , Näslund Tanja I. , Gabrielsson Susanne 
Published: January 2023

Abstract
Exosomes, nanosized endogenous vesicles, can induce adaptive immune responses and have been tested in cancer treatment. Similarly, the iNKT cell ligand α-galactosylceramide (αGC) presented on the MHC class I-like molecule CD1d has been used for therapeutic purposes in cancer trials. Here, we investigated if exosomes can be loaded with αGC to activate iNKT cells and potentiate a cancer-specific adaptive immune response. We show that αGC loaded exosomes readily activate iNKT cells both in vitro and in vivo. In addition, exosomes loaded with αGC and the model antigen ovalbumin (OVA) induced a potent NK and γδ T cell innate immune response, followed by synergistically amplified T and B cell responses. Interestingly, αGC/OVA-loaded exosomes did not induce iNKT cell anergy, in contrast to soluble αGC, and were more potent than soluble αGC and OVA in inducing adaptive immunity. Finally, tumor-bearing mice treated with αGC/OVA-loaded exosomes displayed decreased tumor growth and increased T cell tumor infiltration in comparison to mice immunized with OVA-loaded exosomes in an OVA-specific mouse melanoma model. These results show that exosomes loaded with protein antigen and the glycolipid αGC effectively activate both innate and adaptive immunity, important for future cancer immunotherapy design.
Both plasma kininogen and bradykinin receptors are required for collagen antibody-induced arthritis (P4079)
Authors: Wu Yi , Colman Robert 
Published: January 2023

Abstract
Although experimental and clinical studies have suggested that plasma kallikrein-kinin system (KKS) is involved in arthritis, their role in the disease pathogenesis has never been studied using gene deficient mouse model. High molecular weight kininogen (HK) is a major component of KKS, the activation of which induces HK cleavage to generate proinflammatory bradykinin (BK). In mice, kininogen-1 (Kng1) gene in liver drives production of HK in plasma. We generated a Kng1-/- mouse strain whose liver Kng1 mRNA and plasma HK protein were absent. To induce collagen antibody-induced arthritis (CAIA), three groups of mice (WT, Kng1-/-, and B2RB1R-/- that lack double BK receptors) were injected I.P. with anti-type II collagen antibody cocktail (3 mg) on day 0 and LPS (50 μg) on day 3. WT mice started to develop joint swelling and erythema on day 5, and the increase in ankle joint diameter became marked on day 6 (1.32±0.13 mm) and peaked on day 8 (1.41±0.17 mm). As detected by ELISA, plasma levels of IL-1β were increased on day 8 than day 0 (p&lt;0.01). Real time PCR indicated that IL-1β mRNA in monocytes of WT mice was increased by 3 fold. In contrast, either Kng1-/- or B2RB1R-/- mice did not develop marked joint swelling, their plasma IL-1β and monocytic IL-1β mRNA levels were not significantly increased. Our results demonstrate an essential role of HK in the pathogenesis of arthritis, BK serving as a key mediator. Blockade of HK cleavage has a potential for anti-arthritic treatment.
Gut CD103+ dendritic cells from female lupus-prone (NZBxNZW) F1 (BWF1) mice are much less effective than male BWF1 mice at inducing iTregs (P4087)
Authors: Chhabra Anita , Alard Pascale , Kosiewicz Michele 
Published: January 2023

Abstract
Regulatory CD4+Foxp3+ cells (Tregs) either develop in the thymus (nTregs) or are converted from non-Tregs in the periphery (iTregs). Lupus is much more prevalent in females than males, and although we have found that female BWF1 mice have lower Treg% than males and Treg% are increased in androgen-treated females and decreased in castrated males, it is unclear whether it is the nTregs or iTregs that are affected. In this study, we compared the ability of female and male BWF1 cells to mediate conversion. We found no differences in the ability of female and male BWF1 in vitro generated (bone marrow-derived) dendritic cells (DC) treated with TGFβ to induce Foxp3+ iTregs in vitro. Next, we analyzed CD103+DC from mesenteric lymph nodes (MLN) that can spontaneously induce iTregs. CD103+DC from female BWF1 mice exhibited a dramatically decreased ability to induce iTregs in vitro. CD103+DC from castrated male mice also had a similarly reduced ability to induce Tregs compared to sham-castrated males. Differences in CD103+DC function correlated with Treg% in MLN which were lower in females than males. There were no differences in CD103+DC% in MLN between female and male BWF1 mice. Interestingly, treatment in vivo with a blocking anti-CD103 antibody induced/accelerated disease and increased mortality in male BWF1 mice. Our data suggest 1) androgens may increase tolerogenic function of CD103+DC and 2) CD103+DC may induce a population of iTregs that are important for controlling lupus.
Mechanisms of AIM2 inflammasome regulation (P4093)
Authors: Prasad Amit , Ramirez-Ortiz Zaida , Means Terry 
Published: January 2023

Abstract
Systemic lupus erythematosus (SLE) is an autoimmune syndrome typified by autoantibodies against DNA, chromatin, and RNA-associated proteins. Experimental evidence from our group and others suggests that RNA- and DNA-containing immune complexes isolated from SLE patients activates dendritic cells (DCs) through the nucleic acid sensors TLR7 and TLR9, respectively. Using a highly parallel shRNA pooled screening strategy; we identified several additional genes that positively regulate innate responses to stimulatory RNA and DNA complexes that contribute to SLE pathology. Here we show that triggering receptor expressed on myeloid cells like 4 (Treml4) regulates innate sensing of dsDNA and ssRNA in macrophages and DCs. To validate these findings we generated TREML4-deficient mice. We found that dsDNA or ssRNA stimulation of DCs isolated from TREML4-deficient mice produced significantly less IL-1 beta compared to wild-type DCs. We also observed lower caspase-1 and pro-inflammatory cytokines in Treml4 deficient DCs. In addition, AIM2 expression and function are significantly impaired in TREML4-deficient cells compared to wild-type cells. Our results suggest further study of this new signaling intermediate will give better insight into autoimmune diseases, such as SLE and may serve as a potential therapeutic target.
Modulation of dendritic cell function by neuroantigen-specific CD8+ T cells (P4065)
Authors: Kashi Venkatesh , Ortega Sterling , Tyler Andrew , Karandikar Nitin 
Published: January 2023

Abstract
Experimental autoimmune encephalomyelitis (EAE) studies have established that myelin reactive T cells contribute significantly to the pathology of multiple sclerosis (MS). While auto-reactive CD4+ T cells have long been considered to be pathogenic, the role of CD8+ T cells is relatively unknown. We previously showed that myelin oligodendrocyte glycoprotein-specific CD8+ T cells (MOG-CD8+) suppress EAE; however, the mechanism of disease suppression is not completely understood. Here we show that CD11c+ dendritic cells (DC) from MOG-CD8+ recipient mice are less efficient in priming naïve and in activating recall CD4+ T cell response as compared to control ovalbumin-CD8+ recipients. In response to lipopolysaccharide stimulation, DC from MOG-CD8+ recipients demonstrated an anti-inflammatory cytokine profile with significantly lower IL-12 but higher IL-10 secretion. This was also confirmed in CD8-/- mice where DC from MOG-immunized CD8-/- mice secreted higher levels of IL-12 as compared to wild-type mice. MOG-CD8+ transfer to naïve mice did not affect DC function indicating that DC modulation requires cognate antigen presentation. Kinetic studies revealed that DC were modulated prior to disease onset at day 7 and persisted until day 30 post CD8+ transfer. Overall, our data suggest that transfer of CNS-antigen specific CD8+ T cells modulates DC function and can be an important mechanism of maintaining peripheral tolerance.
Autophagy: a dichotomous player in Toll-like receptor 7-mediated autoimmunity. (P4073)
Authors: Weindel Chi , Richey Lauren , Bolland Silvia , Huber Brigitte 
Published: January 2023

Abstract
The endosomal Toll-like receptor, TLR7, acts as critical line of defense against viral pathogens; however, overexpression of TLR7 has been shown to lead to spontaneous lupus-like disease (SLE). Thus, tight regulation of this pattern recognition receptor is crucial in preventing a hyperactive cellular state. We hypothesized that autophagy plays a role in TLR7 activation by delivering ligand to endosomes and by controlling subsequent inflammatory responses. To test this model, we crossed TLR7 transgenic (tg) mice that succumb to SLE with mice where ATG5, a critical autophagy gene, was deleted in dendritic cells (DCs) or B cells or both. These mice were compared to TLR7 tg mice with intact autophagy for morbidity and the inflammatory response. We observed that loss of ATG5 in either DCs or B cells significantly increased the survival of TLR7 tg mice, while ATG5 deletion in both cell types only modestly improved survival. On the other hand, loss of autophagy led to an elevated inflammatory response compared to TLR7 tg mice with intact autophagy, as evidenced by vastly increased lymphoid organ mass and elevated numbers of granulocytes and macrophages. The inflammatory mediators involved in this process are currently under investigation. These data suggest that autophagy plays an important and dichotomous role in TLR7-mediated autoimmunity, both enabling and ameliorating symptoms of SLE. It is likely that autophagy is affecting multiple TLR7-dependent signaling processes.
TCR signal strength via IRF4 influences CD8 T cell responses to acute LCMV infections (P6096)
Authors: Nayar Ribhu , Prince Amanda , Enos Megan , Daniels Keith , Brehm Michael , Welsh Raymond , Berg Leslie 
Published: January 2023

Abstract
CD8+ T cells undergo rapid proliferation, differentiation and contraction following acute infections. One of the key factors influencing these CD8+ T cell responses is the strength of TCR-ligand interactions. We have previously shown that the transcription factor Interferon Regulatory Factor 4 (IRF4) is important in the differentiation of CD8 T cells. IRF4 is not expressed in naïve CD8 T cells, but is rapidly up-regulated upon T cell activation. Further, this up-regulation is directly regulated by the strength of TCR signaling, such that stronger signaling leads to higher levels of IRF4 expression. To test the function of IRF4 in vivo, we have utilized the acute LCMV infection model together with mice expressing graded levels of IRF4. These studies indicated that CD8 T cell proliferation and differentiation into effector and memory populations is regulated by IRF4. Further, we found that IRF4 was impacting the expression of major downstream transcription factors, Eomes, TBet, and TCF1, that are critical for effector responses and memory differentiation. Together these data establish a transcription factor network that is highly responsive to the strength of TCR-ligand interactions during infection.
Inflammasome adaptor protein ASC is critical for the immune response and survival in West Nile virus encephalitis (P6110)
Authors: Verma Saguna , Roe Kelsey , Kumar Mukesh , Orillo Beverly , Muruve Daniel , Nerurkar Vivek , Gale, Jr. Micheal 
Published: January 2023

Abstract
Innate immune responses are essential for WNV clearance, dissemination and neurovirulence. Pattern recognition receptors and other danger signals activate assembly of inflammasome complex, which modulates antiviral defense responses. ASC is an important adaptor molecule, which mediates downstream signaling pathways of NLRP3 inflammasomes. In this study we defined the role of ASC in WNV immunity. Infection of cultured BMDCs showed that ASC was essential for the activation of caspase-1, a key component of inflammasome assembly. ASC-/- mice were highly susceptible to WNV infection marked by increased mortality, enhanced viremia and virus replication in the CNS. As compared to wild type mice, key cytokines including IL-1β and IFN-γ were significantly reduced in the sera of ASC mice. Additionally, antiviral IFN-α levels were also decreased in the sera of ASC-/- mice. Increased virus titers in the brain of ASC-/- mice correlated with increased inflammation and neuronal apoptosis. However, intracranial inoculation of WNV did not result in significant differences in the virus titers in both groups suggesting that impaired immune response coupled with failure to clear virus in the periphery leads to increased neuropathology and mortality in ASC-/- mice. Collectively, our data provides new insights into the role of ASC as an essential modulator of inflammasome-dependent and -independent immune response to effectively control WNV infection.
Regulation of CXCR3 chemokine production and CD8+ T cell infiltration in the metastatic melanoma microenvironment (P5091)
Authors: Clancy-Thompson Eleanor , Mullins David 
Published: January 2023

Abstract
Vaccine-based immune therapy has shown minimal efficacy against established tumors. However, vaccination in the adjuvant setting prolongs disease-free survival. We previously demonstrated that CXCR3 expression by tumor antigen-specific T cells correlates with this. We hypothesized that melanoma engraftment may induce spatially- and temporally-restricted expression of CXCR3 chemokines in the tumor microenvironment, leading to transient infiltration of CXCR3+ T cells into tumor. We used a model of murine metastatic-like melanoma to evaluate tyrosinase expression as a measure of tumor burden. We observed a positive correlation between tyrosinase and CXCL9 (r2 = 0.73) and CXCL10 (r2 = 0.86) expression over time, demonstrating that melanoma growth in the lung is sufficient to induce CXCR3-cognate chemokines. In a time-course study, we observed that CXCL9 and CXCL10 expression decrease after day 15; we hypothesize that diminished chemokine production is due to reduced interferon signaling. We are investigating this possibility. Our preliminary flow cytometry analyses suggest a positive correlation between CD8+ T cell infiltration and the expression of CXCL9/10, suggesting that metastatic melanomas are transiently receptive to T cell infiltration. Therefore, successful immunotherapy of metastatic melanoma may require adjuvant therapy to induce or extend the chemotactic window for T cell infiltration.