bluuebunny/crossref_metadata_2025_split huggingface dataset:
Costimulatory effects of TLR1-TLR2 stimulation on CD8+ T cells is dependent on 4-1BB signaling (TUM7P.941)
Authors: Joseph Ann , Srivastava Ratika , Zabaleta Jovanny , Kaczanowska Sabina , Davila Eduardo 
Published: January 2023

Abstract
Toll-like receptors (TLRs) play a significant role in amplifying immune responses against tumors. Our studies demonstrate that activated CD8+ T cells express TLRs and upon stimulation with TLR1-TLR2 agonists, exhibit enhanced T cell survival and proliferation. To define how TLR signaling promotes these processes, we compared gene expression analysis between TLR1-TLR2-stimulated and unstimulated CD8+ and MyD88-/- CD8+ T cells and identified significant increases in the expression levels of five TNF family members. We sought to test the hypothesis that the costimulatory effects of TLR1-TLR2 stimulation on CD8+ T cells were dependent on the function of one of these costimulatory molecules. Blocking CD137 (4-1BB) using blocking antibodies, but not the other TNF family members, dramatically reduced the costimulatory effects of TLR-mediated T cell proliferation. Likewise, 4-1BB -deficient CD8+ T cells did not respond to TLR stimulation. While TLR signals are capable of upregulating antiapoptotic proteins such as BCL2 and BCL-xL, mechanistically, we postulate that 4-1BB activation stabilizes these proteins, hence promoting survival. Adoptive transfer of pmel T cells along with the 4-1BB agonistic antibody, 3H3 and the TLR ligand, Pam3CSK4 was able to reduce tumor growth in a B16 melanoma model. These studies indicate that the costimulatory effects of TLR1-TLR2 signaling in CD8+ T cells mediated by 4-1BB signals are vital for mounting an effective antitumor response.
Enhancing the antitumor effects of adoptive cell transfer immunotherapy using preconditioning thermal ablation (TUM7P.956)
Authors: Bucsek Mark , Ito Fumito , Muhitch Jason , Ajith Ashwin , Evans Sharon 
Published: January 2023

Abstract
A major challenge facing T cell based immunotherapeutic strategies is the limited trafficking of cytotoxic T cells at vascular checkpoints within the tumor microenvironment. Here, we report the use of radiofrequency ablation (RFA; 90°C, 1min), a cytoreductive strategy used clinically to treat unresectable tumors, as a pre-conditioning regimen to overcome deficient CD8 T trafficking across tumor vasculature. RFA pre-treatment caused a concomitant decrease in the number of Foxp3+CD4+CD25+ regulatory T cells while bolstering CD8 T cells in tumor draining lymph nodes and the non-ablated region within the tumor microenvironment. Taking advantage of the immunostimulatory activities of RFA, adoptive transfer of antigen-specific T cells was performed 6 hours post-RFA in implantable murine tumors (B16.F10 melanoma or CT26 colorectal tumors). Increased trafficking of adoptively transferred T cells was observed in both the tumor draining lymph node and tumor microenvironment. Improved trafficking was associated with a robust increase in antigen-restricted apoptosis of tumor cell targets and significantly enhanced overall survival without recurrence. Further investigation revealed that adoptive T cell transfer following RFA elicited a durable tumor-specific memory response. Taken together, these findings suggest that thermal ablative regimens may have clinical potential as an adjuvant to augment the efficacy of T cell-based cancer immunotherapies.
HBP1, a novel protein from lamprey can repress proliferation of cancer cells (TUM7P.926)
Authors: Li Qingwei , Pang Yue , Huang Jinsha , Liu Shuang 
Published: January 2023

Abstract
HBP1 ( HMG-box containing protein 1) is homologous to the sequence- specific high mobility group ( HMG) family of transcriptional factor. Previous work had shown that HBP1 inhibits G1 progression in cells. In this paper, we identified a homolog of HBP1 in the Japanese lamprey (Lampetra japonica). The bioinformatics analyses showed that the Lj-hbp1 gene has over 60% sequence identity with its homologs in jawed vertebrates. The open reading frame (ORF) of Lj-HBP1 is 1584 bp long and encoded 527 amino acids. The calculated molecular masses of Lj-HBP1 was 58 kD. Real-time quantitative PCR indicates that the HBP1 appears universally in the lampreys tissues. An Adeno-X-LjHBP1 vector were constructed, HBP1 transcription factor were expressed, and its infection efficiency of the packaged lentivirus were evaluated by PCR method. We found that both human tumor cells and normal cells were infected efficiently as determined by the expression of HBP1. In addition, the proliferation rate and ability of growth in soft agar of the HBP1-transfected Raji cells were suppressed through growth curve test ( population doubling as index) and soft agar assay. The results indicated that modest overexpression of HBP1 inhibited the growth of tumor cells.
Folate-modified chitosan nanoparticles coating IP-10 promote pMAGE-A1278-286 specific CTL responses to liver cancer (VAC11P.1011)
Authors: Lu Xiaoling , Zhao Yongxiang , Su Jing , Zhou Sufang , He Jian , Lai Chunhui , Li Xi , Duan Siliang 
Published: January 2023

Abstract
Adoptive therapy using tumor antigen-specific cytotoxic T lymphocytes (CTLs) is a promising approach for the treatment of human cancers. However, tumor antigen-specific CTLs are difficult to reach tumor tissues because of immune suppressions in cancer patients. Interferon-inducible protein-10 (IP-10), a powerful chemokines, effectively attracts CTLs to tumor tissues and improves the anti-tumor activity of CTLs. Increasing the expression of IP-10 in tumor tissues can efficiently promote the efficacy of adoptive therapy. In this study, we developed folate-modified chitosan nanoparticles coating the human IP-10 gene (FA-CS-hIP-10), that specifically bound to the folate receptors on hepatoma cells and promote the expression of IP-10 to improve the activity of pMAGE-A1278-286 specific CTLs. Combination of FA-CS-hIP-10 and pMAGE-A1278-286 specific CD8+ CTLs efficiently increased the secretion of IFN-γ, inhibited the growth of tumor and extend the survival of nude mice subcutaneously transplanted human liver cancer. Our results demonstrated that the mechanism of this novel adoptive therapy involved in the inhibition of angiogenesis, inhibition of proliferation, and promotion of apoptosis of tumor cells. Our study provided a potentially novel approach for the treatment of human liver cancers by improving the activity of tumor antigen-specific CTLs.
Adoptive T cell immunotherapy using chimeric antigen receptor against a novel cancer target Axl (VAC11P.1007)
Authors: Intisar Ejaj , Walsh Anthony , Weinberg Benjamin , Chakravarti Deboki , Wong Wilson 
Published: January 2023

Abstract
The Axl protein belongs to a subfamily of receptor tyrosine kinase and has been implicated in a large variety of cancers like colorectal, prostate, mesothelioma, breast, etc., beginning from its overexpression initially detected in chronic myeloid leukemia. Hence Axl presents as a novel and promising target for multiple cancer models. Meanwhile chimeric antigen receptor (CAR) is already a developed platform technology used in genetically modified T cells in order to make them recognize and elicit an immune response against cancer cells. Here we designed 3 single-chain variable fragments from existing monoclonal antibodies against Axl and constructed them into third-generation CARs. For testing, we transduced these CARs into Jurkat T cells and primary CD4 T cells. We cultured the cells in different doses of Axl and assayed the level of their activation using flow cytometry and ELISA. All 3 CARs demonstrated functional efficacy in being able to recognize the antigen and produced successful activation. This was detected by increase in GFP expression, cloned downstream of the NFAT promoter in the Jurkat T cell line. Furthermore the primary T cell experiment demonstrated increased secretion of IFNγ for all 3 CARs and IL-2 for 2 CARs. Our study confirmed the successful construction of 3 new therapeutic CARs against the novel cancer antigen, Axl, with varying levels of activation. This can now be utilized in a switchable CAR system to deliver a tunable therapeutic immune response.
Potential of immune biomarkers for predicting survival in glioblastoma patients receiving dendritic cell cancer immunotherapy (VAC12P.1012)
Authors: Visus Carmen , Fischhuber Katrin , Klingenbrunner Simone , Reitermaier Rene , Knausz Heike , Erhart Friedrich , Moricz Sandra , Barresi Caterina , Felzmann Thomas 
Published: January 2023

Abstract
Activartis is developing AV0113, an autologous dendritic cell (DC)-based cancer vaccine for glioblastoma multiforme (GBM). AV0113 is characterized by high release of IL-12, Th1 polarization and a potent anti-tumor immune response. A total of 78 GBM patients have been recruited into a randomized Phase II clinical trial. All patients received first line standard therapy for GBM and patients in the treatment group received AV0113 as an add-on treatment. A recent evaluation revealed a clear trend towards survival benefit for patients receiving AV0113 compared to the control group. In the treatment group 3 of 19 patients had died (16%), whereas in the control group 9 of 20 patients had died (45%). Patients’ chances to survive the first year are close to 3 times greater if they receive AV0113. Based on the hypothesis that there are immune parameters that could predict response to cancer immunotherapy (CIT), we investigated a total of 90 variables in the peripheral blood of GBM patients before, during and after CIT. We detected pre-existing anti-tumor immune responses and found that these responses were higher in patients that survived longer after CIT. Furthermore, a high increase in the anti-tumor responses after CIT was observed in long-term survivor patients and was associated with high percentage of CD3, CD8, NK and Th1 phenotypes as well as lower T regulatory cells in the peripheral blood. These Immune Parameters might be used as prognostic biomarkers and guidance for CIT.
Somatic hypermutation and use of immunoglobulin variable regions at shark T cell receptors (VET2P.1038)
Authors: Criscitiello Michael , Eubanks Jeanine , Chen Pat , Castro Caitlin , Wallace Andrea , Ota Yuko , Flajnik Martin 
Published: January 2023

Abstract
The nurse shark (Ginglymostoma cirratum) is part of the earliest clade found to possess an adaptive immune system employing immunoglobulin superfamily lymphocyte antigen receptors. The hallmarks of adaptive immunity, memory and specificity, are accomplished through B or T cells employing immunoglobulin (Ig) or T-cell receptors (TCR) respectively. Both lineages undergo somatic gene rearrangement for receptor diversification, a process mediated by RAG proteins, in which V, D, and J gene segments are joined together. Surprisingly, we found somatic hypermutation (SHM, normally a B cell process) to occur extensively at shark TCRα loci. Unlike B cell SHM that follows antigen exposure in sharks and most other vertebrates, SHM at TCRα loci occurs during thymic development. TCRα SHM is supported with isolation of clusters of mutated clones having the same CDR3 rearrangement.We suggest that such SHM, in addition to TCRα receptor editing, permits developing T cells with evolving receptors to scan cortical epithelial cells for positive selection on self-peptide/self MHC. Additionally, we have found that shark TCRδ can employ variable gene segments of IgM and IgW in rearrangements, a situation that may be similar to the IgHV use by TCRδ noted in higher vertebrates. Future studies must further study the lineage commitment of shark B and T cells and the receptor plasticity of these lineages in all vertebrates.
Bovine monocyte-derived dendritic cell populations from animals in late gestation show altered response to E. coli (VET2P.1039)
Authors: Pomeroy Brianna , Sipka Anja , Klaessig Suzanne , Schukken Ynte 
Published: January 2023

Abstract
During late gestation the bovine immune system is less capable of eliminating pathogens. Most new intra-mammary infections occur in late gestation, and the majority of these infections are caused by E. coli. Unlike non-pregnant, lactating cows, late gestation cows are unable to elicit an effective inflammatory response to intra-mammary infection caused by E. coli. During pregnancy, the immune system appears to shift to a humoral, anti-inflammatory, so called T helper 2 bias with increased tolerance. Dendritic cells are antigen presenting cells that orchestrate activation and differentiation of naive T cells, and they are hypothesized to play a key role in directing the T helper 2 bias and immune tolerance observed in gestation. We stimulated monocyte-derived dendritic cells with E. coli and compared responses from late gestation cows to those of non-pregnant cows. Results show monocyte-derived dendritic cells from late gestation cows have altered surface molecule expression and cytokine production compared to those from non-pregnant cows. Our findings support the hypothesis that late gestation bovine dendritic cells are likely to produce suboptimal T cell activation in response to E. coli antigens, and play a role in observed immune-bias in pregnancy. In addition, altered dendritic cell function in gestation may impede current, routine vaccination regiments in late gestation. Future work will identify likely pregnancy-factors that modulate bovine dendritic cell responses.
Suppression of B cell responsiveness by LP-BM5 retrovirus-induced myeloid derived suppressor cells generated during a murine acquired immunodeficiency syndrome: a role for negative checkpoint regulator expression on the MDSCs (VIR7P.1059)
Authors: Green Kathy , Wang Li , Green William 
Published: January 2023

Abstract
The inhibitory activities of myeloid derived suppressor cells (MDSC) against T cell responses are well established in tumor microenvironments. We published (2013, J. Virol. 87:2058-2071) on the induction of monocytic MDSCs during infection of susceptible B6 mice by LP-BM5 retrovirus, which causes a profound immunodeficiency. These MDSCs inhibited not only T, but also B cell, responsiveness to polyclonal stimulation in ex vivo suppression assays. Whereas MDSC inhibition of stimulated T cell proliferation and IFN-gamma production was largely iNOS/NO dependent, MDSC suppression of B cell responses was only partially (~50%) due to iNOS/NO - as shown by using iNOS inhibitors and LP-BM5 infected iNOS k.o. mice as a source of MDSCs. Here, we further study additional suppressive mechanism(s) in the MDSC inhibition of B cell responsiveness. Using MDSCs from LP-BM5 infected mice of negative checkpoint regulator knock-out origin, and specific blocking antibody, MDSC suppression of B cell responses was partly dependent on MDSC expression of certain checkpoint regulators. Combining the use of reagents to interrupt both iNOS/NO and checkpoint regulation lead to a synergistic blocking of MDSC suppression of B cell responsiveness. These results were compatible with a role for MDSC in LP-BM5 induced immunodeficiency and highlight the involvement of multiple and unique suppressive pathways in the under-studied area of MDSC suppression of B cell responses.
T and B cell memory responses in 2012 filovirus outbreak survivors (VIR7P.1060)
Authors: Stonier Spencer , Herbert Andrew , Sobarzo Ariel , Kuehne Ana , Eskira Yael , Lutwaama Julius , Lobel Leslie , Dye John 
Published: January 2023

Abstract
From 2011 to the present, there have been four confirmed filovirus outbreaks with a fifth case involving a single patient. Four outbreaks/cases were attributed to the Ebolavirus genus, with Marburgvirus responsible for one. With the high lethality rates seen in these outbreaks (generally ~40-90%), and the potentially dramatic disease sequelae, filovirus outbreaks can devastate local communities and present great health risks for affected regions. These issues obviate the need for effective vaccines and therapeutics to limit and manage future outbreaks. In 2012 alone, three outbreaks occurred in Uganda - two of Sudan virus and one Marburg virus. We collected PBMC and serum samples from survivors from each outbreak to evaluate the presence of immune memory and its composition. Serum antibodies displayed broad specificity to Marburg virus and Sudan virus glycoprotein in addition to other proteins. Virtually all serum samples displayed neutralizing activity. PBMCs stimulated with viral and recombinant antigen were evaluated by flow cytometry for functional parameters as well as level of antigen-responsive T cells. Cytokines in the supernatants of these cultures were determined by multiplex ELISA. Cytokine responses were largely pro-inflammatory produced predominantly by CD4 T cells. Establishing immune memory parameters and the nature thereof gives us targets for vaccine development and opens avenues for development of immune-based therapeutics.
Provirus activation plus CD59 blockage triggers antibody-dependent complement-mediated lysis of latently HIV-1-infected cells (VIR7P.1050)
Authors: Yu Qigui , Lan Jie , Byrd Daniel , Hu Ningjie , Amet Tohti , Shepherd Nicole , Desai Mona , Yang Kai , Gupta Samir 
Published: January 2023

Abstract
Latently HIV-1-infected cells are recognized as the last barrier towards viral eradication and cure. To purge these cells, we combined a provirus stimulant with a blocker of human CD59, a key member of the regulators of complement activation (RCA), to trigger antibody-dependent complement-mediated lysis (ADCML). Provirus stimulants including romidepsin (RMD), suberoylanilide hydroxamic acid (SAHA) and prostratin activated proviruses in the latently infected T cell line ACH-2 as virion production and viral protein expression on the cell surface were induced. These results would lead to cytolytic clearance by viral cytopathic effects (CPEs), host immune responses or both. Immune attack against provirus-activated cells is critical as antiretroviral drugs did not affect the percentage of cells expressing viral proteins, but markedly suppressed virus production, thereby attenuating CPEs. RMD was the most attractive provirus stimulant as it not only effectively activated proviruses at nanomolar concentrations, but also enhanced cell surface expression of MHC-I and NK cell-activating receptors, potentially rendering these cells sensitive to cell-mediated immunity. Provirus-activated ACH-2 cells became sensitive to ADCML in the presence of a CD59 blocker plus anti-HIV-1 antibodies or plasma from HIV-1-infected patients. Therefore, a combination of provirus stimulants with RCA blockers represents a novel approach to eliminate HIV-1.
A first look at the protective immunity elicited by the yellow fever virus 17D live-attenuated vaccine (VIR7P.1051)
Authors: Watson Alan , Lam LK Metthew , Gardner Christina , Klimstra William , Ryman Kate 
Published: January 2023

Abstract
A hallmark of anti-viral vaccination for 77 years has been the safe and effective live-attenuated 17D yellow fever virus (YFV) vaccines. Among more than 500 million individuals vaccinated, only five cases of yellow fever have been reported. This efficacy is presumed to be the result of both neutralizing antibodies and a robust CD4+ and CD8+ T cell response. However, the importance of these immune components for protection following YFV challenge has never been evaluated. For the first time, we have addressed this question using a murine model in which YFV infection is lethal and 17D immunization protects 100 percent of animals. Similar to humans, vaccination in mice elicits life-long protection against challenge characterized by high neutralizing antibody titers and a robust polyfunctional T cell response. YFV-specific T cells express markers congruent with the differentiation of long-term memory. Additionally, T cell mediated cytotoxicity is detected for greater than one year post vaccination against MHC-I and MHC-II restricted targets. Adoptive transfer of immune sera or CD4+ T cells alone provides partial protection against YFV, but CD8+ T cells do not contribute to disease mitigation. Complete protection from disease requires both immune sera and CD4+ T cells. Further understanding the immune mechanisms that make 17D an effective vaccine will aid in the improvement of 17D-chimeric vaccines targeting flaviviruses and other pathogens.
Differentiation and function of murine gammaherpesvirus specific CD4+ T cells (VIR7P.1052)
Authors: Hu Zhuting , Blackman Marcia , Usherwood Edward 
Published: January 2023

Abstract
Gammaherpesvirus infection in AIDS patients is associated with severe disease. CD4+ T cells are essential for immune control of viral infection and prevention of malignancy. Progressive loss of CD4+ T cells results in an erosion of immune surveillance, which may lead to gammaherpesvirus associated tumors. A recently generated murine gammaherpesvirus-68 gp150-specific TCR transgenic mouse provides a model for studying CD4+ T cells more precisely. We aimed to study differentiation of MHV-68-specific CD4+ T cells and the contribution of the CD4+ T cells in immune responses independent of CD8+ T cells and B cells. The gp150-specific CD4+ T cells differentiated into two interconvertible populations based on Ly6C expression. The majority of these cells differentiated into Th1 cells, producing IFN-γ and expressing T-bet but not eomes, GATA3, RORγ or Bcl6. Ly6C expression was positively correlated with T-bet expression, IFN-γ, TNF-α and granzyme B production. The gp150-specific CD4+ T cells prolonged survival of MHV-68-infected mice and controlled growth of MHV-68-immortalized SL1 cells in gp150-Tg mice without CD8+ T cells and B cells. Their antiviral functions were dependent on IFN-γ, and the CD4+ T cells also had cytolytic activity. In summary, CD4+ T cells that arise during MHV-68 infection are mostly Th1 and display antiviral ability in the absence of CD8+ T cells and B cells through IFN-γ.
Contribution of DCs and monocytes/macrophages to disease control or progression in SIVmac251-infected Mamu-B008+ rhesus macaques (VIR8P.1065)
Authors: Bouwer Anthea , Smith Amanda , Swan Zachary , Barratt-Boyes Simon 
Published: January 2023

Abstract
Dendritic cells (DC), monocytes and macrophages are known to play a critical role in the induction of antiviral immune responses. However in the case of HIV/SIV, it remains unclear if this response is beneficial or detrimental in the progression of the disease. To examine the host-virus relationship we are longitudinally following the viral load and assessing the DC and monocyte/macrophage responses in the blood, lymph nodes and ileum of SIVmac251-infected Mamu-B*008+ rhesus macaques. Mamu-B*008 is an MHC class I allele highly correlated with control of SIV replication and a model for controlled and progressive HIV-1 disease. Previous studies have shown that approximately 50% of Mamu-B*008+ rhesus macaques control SIVmac239 replication in the chronic phase in a manner resembling elite control that has been observed in a small subset of HIV-infected humans. Utilizing intracellular cell staining, we are currently investigating the inflammatory cytokine contributions of pDC, mDC and monocytes/macrophages during disease progression. Preliminary findings suggest that pDC may not solely be responsible for the persistent interferon response, characteristic of HIV/SIV infection. As our study continues, we hope to gain a more complete understanding of the roles that DC and monocytes/macrophages play in the progression or control of SIV infection.