bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hematopoietic expression of CXCR3 is required for melanoma engraftment of lung (TUM7P.936)
Authors: Clancy-Thompson Eleanor , Mullins David 
Published: January 2023

Abstract
Chemokine receptors have an established role in immune cell trafficking, and a less well-defined role in metastasis. Recent literature has demonstrated a role for tumor-expressed CXC chemokine receptor 3 (CXCR3) in metastasis to lymph nodes, but no study has evaluated the role of host CXCR3 expression in melanoma metastasis. To assess this possibility, we injected B16 melanoma intravenously into CXCR3wt or CXCR3-/- mice and assayed for melanoma-specific gene expression (tyrosinase) 24 hours later. Gene expression was significantly (9.5-fold) higher in CXCR3wt mice. At 24h, this is likely due to differential engraftment of the melanoma in the lung, as opposed to different growth. To determine if the CXCR3-expressing host contribution is an immune component, we phenotyped cells in the lungs 24 hours after melanoma injection. Neutrophils, CD8+ T cells, and B cells were significantly increased in CXCR3-/- mice versus CXCR3wt mice after melanoma injection, whereas macrophages/DCs, CD4+ T cells, and NK cells were not significantly different. Using bone marrow chimeras, we have shown that melanoma engraftment in the lungs requires a host CXCR3-expressing cell of the hematopoietic cell lineage. A role for host CXCR3-expressing cells to mediate melanoma engraftment in the lungs has not been previously shown, and these studies may predict future targets for the reduction or prevention of melanoma metastases in patients.
Development of protease activated interleukin-12 cytokine fusion proteins for tumor immunotherapy (TUM7P.946)
Authors: Skrombolas Denise , Maharaj Shivana , Wylie Isabel , Sullivan Mark , Shenoy Gautam , Bankert Richard , Frelinger John 
Published: January 2023

Abstract
Local expression of IL-12 in the tumor microenvironment results in greatly enhanced anti-tumor responses. However, achieving local expression of cytokines at disseminated sites is challenging and systemic delivery has significant toxicity. We describe a novel approach employing an activatable fusion protein (FP) to reduce the negative side-effects of systemic delivery of the cytokine but which can preferentially affect all tumor sites. This FP consists of a cytokine linked to an inhibitory single chain antibody fragment (scFv) separated by a specific protease cleavage sequence. Importantly, the scFv does not bind to the tumor but rather binds to the cytokine keeping it inactive. However, at the tumor site, the FP can be cleaved by proteases such as Matrix metalloproteases (MMPs) that are over-expressed at tumor sites. This cleavage allows the release of the cytokine from the scFv and its binding to higher affinity receptors on immune cells. We will present data on the construction, expression, and characterization of a panel of murine and human IL-12 FPs. Using phage display, we have identified a panel of 15 scFv that bind to epitopes of murine IL-12 on either the P35 or P40 subunit as well as scFv that bind to human IL-12. Functional and biochemical data on baculovirus expressed IL-12 FPs will be presented. This strategy has the potential to reduce the negative side effects associated with systemic delivery of constitutively active cytokines yet retain their efficacy.
Serum prevalence of B cell stimulatory TLR ligands, elevated B cell TLR2 expression and regulatory B cell frequency precede the genesis of HIV-non-Hodgkin’s lymphoma (NHL) in ART treated HIV+ subjects (TUM7P.951)
Authors: Siewe Basile , Pham Joey , Cohen Mardge , Hessol Nancy , Levine Alexandra , Martinez-Maza Otoniel , Landay Alan 
Published: January 2023

Abstract
TLR2-signaling may contribute to B-cell activation during HIV infection leading to HIV-NHL genesis; a common malignancy in anti-retroviral therapy (ART) treated patients. TLR-signaling and anti-tumor immunity inhibitory regulatory B cells (Bregs) contribute to lymphomagenesis but their roles in HIV-NHL genesis remain unexplored. We investigated, if in HIV- donors, TLR-activated B cells mimic an activated/germinal center (GC)-like phenotype aberrantly expressed in B-cell lymphomas. Further, in HIV+ART subjects: (cases = &lt;1 year pre-NHL, controls = HIV+ART but don’t develop NHL), we assessed: 1) B-cell TLR2 and TLR2 modulatory miRNA expression 2) Breg frequency and 3) serum levels of TLR-ligands. In B cells from HIV- donors only TLR2- (unlike TLR4 nor 9) stimulation (p=0.03), leads to an aberrant phenotype (CD10+CD71+CD86+AID+) identified in lymphomas. Compared to controls, cases exhibit significantly elevated: 1) frequency of CD10+CD71+CD86+AID+ B cells (p=0.01) and Bregs (p=0.0071), 2) serum levels of TLR2 and TLR9 ligands (lipoteichoic acid, p=0.03 and 16s DNA, p=0.03 respectively), 3) B-cell TLR2 expression (p=0.0024). Finally, in cases, the activated/GC-like cells exhibit dysregulation of miRNA regulating TLR2-expression including miR-9, miR-19a and miR146a. Our data suggest that HIV-NHL genesis is associated with aberrant GC-like B cells, elevated Bregs and a possible role for TLR2-stimulation.
CD28 mediated survival in plasma cells involves redox regulator thioredoxin (TUM7P.954)
Authors: Nair Jayakumar , Koorella Chandana , Murray Megan , Carlson Louise , Boise Lawrence , Lee Kelvin 
Published: January 2023

Abstract
Very little is known about the molecules that mediate essential prosurvival interactions between plasma cells (PC) and bone marrow stroma. We have shown that both normal and transformed plasma cells (myeloma, MM) express CD28 (prototypic T cell costimulatory molecule) that correlates with increased survival in MM. We had previously shown that CD28 activation directly with agonistic antibodies or indirectly with CD80/CD86+ (CD28 ligands) dendritic cells protect MM cells against cell death. MM-CD28 also interacts with other CD86+ MM cells to maintain enhanced survival that can be reversed with CD86 blockers like CTLA4Ig. Additionally, we also show that CD28 activation is essential to help plasma cells overcome intrinsic redox stress, a result of increased protein synthesis and metabolic activity (Bertolotti et al., 2010) which if not regulated can lead to cell death. For the first time, we show that CD28 activation not only drives survival via increased NFκB activity, but it also decreases ROS levels via the redox regulator thioredoxin (TRX-1), inhibition of which increased ROS, decreased TRX-1 expression and NFκB activity and reversed CD28 mediated survival in MM. Also, TRX-1 inhibition enhanced CTLA4Ig’s anti-survival effect on MM. Interestingly, gene expression datasets of long lived plasma cells from patients correlate with TRX-1 expression with increased survival, highlighting the vital role this redox regulator plays in PC survival.
Increased lung/liver metastasis of human breast cancer cells in NOD.SCIDIL2rγ-/- mice after treatment with soluble CD200Fc (TUM7P.922)
Authors: Gorczynski Reg , Chen Zhiqi , Khatri Ismat , Podnos Anna , Kos Olha 
Published: January 2023

Abstract
CD200 overexpression increases metastasis of tumor cells to draining lymph nodes. Increased levels of a soluble form of CD200, sCD200, occur in serum of ~50% breast cancer patients, and an immunoadhesin, linking CD200 to an immunoglobulin Fc region (CD200Fc) increases metastasis in experimental models. We investigated whether CD200 levels were increased in human breast cancer cells in mice, and if overexpression of CD200 increased metastasis. NOD.SCIDIL2rγ-/- mice received 5x105 cells of different human breast cancer cell lines (MCF7; HTB19; MDA-MB-231) injected into the mammary fat pad. Groups of mice received ongoing infusion of human CD200Fc (20μg/mouse at 72hr intervals for 4 weeks). Tumors were resected at ~0.7cm3, and snap frozen for PCR analysis. Mice were monitored post resection, and sacrificed 2-3 months later. Lung and liver metastatic nodules were enumerated, and tissue snap frozen for PCR analysis. All tumors growing in NOD.SCIDIL2rγ-/- mice expressed CD200, though parent (in vitro) cell lines were uniformly negative. CD200Fc increased lung and liver metastasis of all breast cancer lines tested. Tumor metastasis was associated with changes in gene expression in tumor tissue, with significant alterations in genes encoding matrix metalloproteinases, and transcription factors modulating inflammation. Further changes in gene expression were attributed to the effect of CD200Fc infusion. Our data suggests increased soluble CD200 promotes human breast cancer metastasis.
TLR7/8 agonists enhance FcγR in CLL patient monocytes (TUM7P.958)
Authors: Elavazhagan Saranya , Shah Prexy , Fatehchand Kavin , Patel Hemal , Cheney Carolyn , Muthusamy Natarajan , Vasilakos John , Matthews Maura-Ann , Dietsch Gregory , Hershberg Robert , Byrd John , Tridandapani Susheela , Butchar Jonathan 
Published: January 2023

Abstract
Monoclonal antibody therapy has been used to treat cancer since 1997, but there is a continued need to improve its effectiveness. We have previously shown that the TLR7/8 dual agonist R-848 could modulate monocyte FcγR expression and function, and that it synergized with antibody to reduce tumor growth rate in vivo. Hence, the purpose of this study was to test whether these agonists could enhance antibody-mediated effects in patient samples and to determine whether it was TLR7, TLR8 or both that drove these FcγR responses. Using peripheral blood samples from Chronic Lymphocytic Leukemia (CLL) patients we found that treatment with the TLR7/8 dual agonist R-848 significantly enhanced monocyte FcγR-mediated TNFα production. In patient Peripheral Blood Mononuclear Cells (PBMC) treated with the anti-CD20 antibody Rituximab, R-848 increased both cytokine production and CLL cell clearance. We next compared the effects of TLR7- versus TLR8-selective agonists on monocytes and found that TLR8 agonists led to greater FcγR-mediated cytokine production, higher levels of miR-155 and lower levels of SHIP-1. Unexpectedly, while all agonists upregulated the activating FcγR, only TLR8 agonists downregulated the inhibitory FcγRIIb. These results suggest that TLR8 agonists are superior to those for TLR7 with regard to enhancing monocyte FcγR expression and function, and may be better adjuvants for antibody therapy.
Direct T cell activation via CD40 ligand generates high avidity CD8+ T cells capable of breaking immunological tolerance for the control of tumors (VAC10P.965)
Authors: Soong Rueyshyang , Wu Tc , Hung Chien-Fu 
Published: January 2023

Abstract
CD40 and CD40 ligand (CD40L) are costimulatory molecules that play a pivotal role in the proinflammatory immune response. Here, two tumor-associated antigen (TAA) animal models, a p53-based and a GP100-based model, were utilized to examine the ability of CD40-CD40L to improve antigen-specific CTL-mediated antitumor immune responses. Although p53 and GP100 are self-antigens that generate low affinity antigen-specific CD8+ T cells, studies have shown that their functional avidity can be improved with CD40L-expressing APCs. Therefore, in the current study, we immunized mice with a DNA construct encoding a TAA in conjunction with another encoding CD40L via intramuscular injection followed by electroporation. We observed a significant increase in the antigen-specific CTL-mediated immune responses and potent antitumor effects in both models. Antibody depletion experiments demonstrated that CD8+ T cells play a crucial role in eliciting antitumor effects in vaccinated mice. Furthermore, we showed that in vitro stimulation with irradiated tumor cells expressing both TAA and CD40L improved the avidity of antigen-specific CD8+ T cells. Thus, our data show that vaccination with a TAA/CD40L DNA can induce potent antitumor effects against TAA-expressing tumors through the generation of high avidity antigen-specific CD8+ T cells. Our study serves as an important foundation for future clinical translation.
Tumor-specific CD8+ Tc9 cells are superior effector than Tc1 cells for adoptive immunotherapy of cancers (VAC11P.1000)
Authors: Lu Yong , Hong Bangxing , Li Haiyan , Zheng Yuhuan , Zhang Mingjun , Qian Jianfei , Yi Qing 
Published: January 2023

Abstract
Because cytokine-priming signals direct CD8+ T cells to acquire unique profiles that affect their ability to mediate specific immune responses, here we generated a novel IL-9-skewed (Tc9) CD8+ T cells by priming with Th9-polarized condition. Compared with Tc1 cells, Tc9 secreted different cytokines and were less cytolytic in vitro but surprisingly elicited greater antitumor responses against advanced tumors in OT-I/B16-OVA and Pmel-1/B16 melanoma models. After adoptive transfer, Tc9 cells persisted longer and differentiated into IFN-g- and granzyme-B (GrzB)-producing cytolytic Tc1-like effector cells. Phenotypic analysis revealed that adoptively transferred Tc9 cells secreted IL-2 and were KLRG-1low and IL-7Rahigh, suggesting that they acquired a signature of “younger” phenotype or became long-term lived cells with capacity of self-renewal. Our results also revealed that Tc9-mediated therapeutic effect was critically dependent on IL-9 production in vivo. These findings have clinical implications for the improvement of CD8+ T cell-based adoptive immunotherapy of cancers.
α-Galactosylceramide stimulates splenic lymphocyte proliferation in vitro and increases antibody production in vivo in the late neonatal-age mouse. (VAC12P.1028)
Authors: Chen Qiuyan , Ross A. 
Published: January 2023

Abstract
The neonatal stage is characterized by weak responses to various infections and vaccines; thus the development of efficient formulas to improve vaccine effectiveness is of high priority. The glycolipid alpha galactosylceramide (αGalCer) is known as a potent immune modulator mainly due to NKT cell activation. Using a mouse tetanus toxoid (TT) immunization model, we observed that neonatal mice given αGalCer at the time of primary immunization on day (d) 17 had a significant higher TT-specific IgM response (ELISA), while given αGalCer at d7 during immunization only resulted in a marginal boosting. Consistently, immunostaining of the spleen sections from αGalCer-treated d17 immunized neonates showed higher number of Ki67+ cells in the splenic germinal center area, suggesting stronger response after immunization. In vitro kinetic studies revealed that spleen cells from newborn to d7 neonates did not respond to αGalCer stimulation, whereas cell proliferation was markedly increased by αGalCer after d7, and became dramatic around neonatal d17-18, which was accompanied by increased B and T lymphocyte populations in the spleen. In addition, in d17 spleen cells, αGalCer significantly stimulated the proliferation of CD23+ B cells, a subset of B cells enriched in germinal centers. These data suggest that αGalCer is an effective stimulator of the immune system in late neonatal stage and thus may be useful as a potential adjuvant to achieve an efficient immunization.
In vivo immunogenicity of Tax 11-19 epitope in HLA-A2/DTR transgenic mice: implication for dendritic cell-based anti-HTLV-1 vaccine (VAC12P.1020)
Authors: Sagar Divya , Masih Shet , Schell Todd , Jacobson Steven , Wigdahl Brian , Khan Zafar , Jain Pooja 
Published: January 2023

Abstract
Viral oncoprotein Tax plays key roles in transformation of human T cell leukemia virus (HTLV-1)-infected T cells leading to adult T cell leukemia (ATL), and is the key antigen recognized during HTLV-associated myelopathy (HAM). In HLA-A2+ asymptomatic carriers as well as ATL and HAM patients, Tax(11-19) epitope exhibits immunodominance. Here, we evaluate immunotherapeutic potential of this epitope in HLA-A2 transgenic mice in the presence and absence of dendritic cells (DCs) given the recent encouraging observations made with Phase 1 DC-based vaccine trial for ATL. To facilitate these studies, we first generated an HLA-A2/DTR hybrid mouse strain carrying the HLA-A2.1 and CD11c-DTR genes. We then studied CD8 T cell immune response against Tax(11-19) epitope delivered in the absence or presence of Freund’s adjuvant and/or DCs. Overall results demonstrate that naturally presented Tax epitope could initiate an antigen-specific CD8 T cell response in vivo but failed to do so upon DC depletion. Presence of adjuvant potentiated Tax(11-19)-specific response. Elevated serum IL-6 levels coincided with depletion of DCs whereas decreased TGF-β was associated with adjuvant use. Thus, Tax(11-19) epitope is a potential candidate for the DC-based anti-HTLV-1 vaccine and the newly hybrid mouse strain could be used for investigating DC involvement in human class-I-restricted immune responses.
Mitochondrial DAMPs stimulate TNF-alpha production by canine splenocytes in an in vitro model of SIRS inflammation (VET2P.1045)
Authors: Strange Heather , Friedenberg Steven , VanGundy Zachary , Guillaumin Julien , Crouser Elliot , Papenfuss Tracey 
Published: January 2023

Abstract
The systemic inflammatory response syndrome (SIRS) is a life-threatening condition that arises secondary to massive immune system activation or dysregulation. Damage associated molecular patterns (DAMPs) are endogenous danger signals released after trauma or sepsis that trigger these potent immune responses. DAMPS derived from mitochondrial fractions have been shown to be pro-inflammatory in mouse models and play a role in human disease. However, the role of mitochondrial DAMPs as a trigger of SIRS in dogs has not been explored. In this study we characterized the response of canine splenocytes to mitochondrial DAMPs and developed an in vitro model system to study SIRS-induced immune dysregulation in dogs. We demonstrated that splenocytes respond to crude fractionated mitochondrial and soluble protein fractions by upregulating TNF-alpha, a described biomarker for SIRS. We further studied the effects of these DAMPs on splenocyte myeloid cell subpopulations (i.e. dendritic cell and macrophage) and found similar upregulation of TNF-alpha. Our findings mimic studies in mouse splenocyte models where mitochondrial DAMPs were shown to promote TNF-alpha release, suggesting that the in vitro model employed here is useful to study the impact of mitochondrial DAMPs in dogs. Given that dogs are increasingly being used to model and optimize therapy for human disease, these results have direct applications in understanding the role of mitochondrial DAMPs in both canine and human SIRS.
Evaluation of a Pmp18D vibro cholerae ghost vaccine against chlamydia abortus in mice (VET2P.1046)
Authors: Pan Qing , Pais Roshan , Ohandjo Adaugo , He Cheng , Eko Francis 
Published: January 2023

Abstract
Chlamydia abortus (C. abortus) is an obligate intracellular pathogen that causes abortion in pigs and poses a zoonotic risk in pregnant women. Currently available attenuated and inactivated vaccines show marginal protective efficacy underlining the need for the development of effective vaccines. Recombinant proteins expressed on gram negative bacterial envelopes are known to induce protective immunity (Th1) without the need of any additional adjuvant. Pmp18D is a member of polymorphic outer membrane protein family of C.abortus. The PmpD protein of C. abortus is expressed throughout the chlamydial developmental cycle. Pmp protein family members are known to exhibit higher immunogenicity. In this study an evaluation of immune responses to Vibrio cholerae ghosts expressing Pmp18D(rVCG) was done in comparison to rPmp18D codelivered with either Flt3L or CpG. Mice were immunized 3 times intranasally 2 weeks apart .By day 14 post last immunization, the rVCG vaccine elicited significantly higher levels of antigen-specific IgG2a and IgA antibodies both in serum and in vaginal washes. Proliferative responses of mucosal (genital tract) as well as splenic (systemic) T cells were significantly higher in mice receiving rVCG vaccine.These results indicate that the rVCG-Pmp18D vaccine is capable of inducing antigen-specific cellular and humoral immune responses that may provide protective immunity against a live challenge infection with C.abortus.
Suppression of T and B cell responses by myeloid derived suppressor cells after natural CD4 T regulatory cell depletion and LP-BM5 retrovirus infection (VIR7P.1057)
Authors: O'Connor Megan , Green William 
Published: January 2023

Abstract
Immunomodulatory cellular subsets, including myeloid derived suppressor cells (MDSCs) and T regulatory cells (Tregs), contribute to the immunosuppressive tumor microenvironment and have been targets of immunotherapy, but their role in retrovirus-associated immunosuppression is less understood. Tregs are associated with HIV-infected patients, however it remains unclear whether Tregs suppress the anti-viral immune response or dampen HIV viral spread; and also unclear is the stage(s) of infection of Treg involvement. MDSCs have only recently been identified in HIV-infected patients, and thus the phenotype and mechanism(s) of suppression are still being defined. Due to known crosstalk between Tregs and MDSCs in the tumor microenvironment, it is of interest to look at the interplay between these cellular types during LP-BM5-induced murine AIDS (MAIDS). Following in vivo nTreg depletion, using adoptive transfer approaches, and subsequent LP-BM5 retroviral infection, enriched MDSCs from infected nTreg-depleted mice exhibit increased suppression of T cell, but not B cell, responses, as compared to MDSCs derived from non-depleted LP-BM5 infected controls. In addition, MDSCs from LP-BM5-infected nTreg-depleted mice have altered phenotypic subsets, which may correlate with functional differences. These collective data may provide insight into the possible immunotherapeutic targeting of Tregs and MDSCs during retroviral infection. (NIH AI007363, CA50157)
Synergistic effects of the inhibitory Fc receptor FcγRIIB deficiency and lupus-associated SLAM family genes on breaking germinal center tolerance checkpoint (BA2P.126)
Authors: Soni Chetna , Wong Eric , Khan Tahsin , Wakeland Edward , Rahman Ziaur 
Published: January 2023

Abstract
The inhibitory Fc receptor FcγRIIB deficiency and lupus-associated signaling lymphocyte activation molecules (SLAMs) are suggested to contribute to autoimmunity in FcγRIIB deficient mice generated using 129Sv/J ES cells and backcrossed to B6 mice (B6-129.RIIBKO). To study the individual contribution of FcγRIIB deficiency and 129-derived SLAM genes to loss of germinal center (GC) tolerance we compared B6 mice deficient in FcγRIIB (B6.RIIBKO) and B6 mice congenic for 129-derived SLAM locus (B6.129-SLAM) with B6-129.RIIBKO and B6 controls. B6-129.RIIBKO mice developed numerous spontaneous germinal centers (Spt-GCs) with increased size producing high titers of autoantibodies against nuclear (ANA) and other self-antigens, alongside a hyperactive T cell phenotype. We also observed elevated Spt-GC and T-cell responses in B6.RIIBKO and B6.129-SLAM mice than B6 mice although much lower when compared to B6-129.RIIBKO mice. B6.RIIBKO and B6.129-SLAM mice also failed to produce high titers of ANAs in comparison to B6-129.RIIBKO. Ex vivo assays revealed that differentially expressed 129-SLAM genes promoted higher expression of activation molecules on B cells, T cells and DCs while FcγRIIB deficiency was sufficient to drive proliferation of B cells and T cells. Our results suggest that the co-operative effects of 129-derived SLAMs on activation and FcγRIIB deficiency on the proliferation of B cells and T cells are essential for breaking the GC tolerance checkpoint in B6-129.RIIBKO mice.