bluuebunny/crossref_metadata_2025_split huggingface dataset:
Forcing NF-κB in T cells promotes tumor rejection (P2042)
Authors: Evaristo Cesar , Molinero Luciana , Gajewski Thomas , Alegre Maria-Luisa 
Published: January 2023

Abstract
T cells from tumor-bearing hosts have reduced NF-κB activity. Our previous results indicate that reduced NF-κB activation results in impaired T cell survival, decreased Th1 differentiation and increased iTreg differentiation. We hypothesized that forced activation of NF-κB in T cells should have the opposite effect, which would be beneficial for tumor rejection. We generated mice with constitutively active IKKβ in T cells (CA-IKKβ mice). T cell numbers were comparable to littermate controls, but CA-IKKβ mice had fewer Tregs and increased frequency of activated T cells that produced IFNγ and IL-4 upon re-stimulation. When B16-SIY melanoma cells were injected subcutaneously, tumors grew progressively in control littermates, but were rejected by CA-IKKβ mice. Tumor control was associated with a massive increase in the number of tumor-specific IFNγ-producing CD8+ T cells and IFNγ blockade restored tumor growth. CA-IKKβ+ CD8+ T cells were able to control tumor growth in the absence of CD4+ T cells. Interestingly, CA-IKKβ+ CD4+ T cell help was sufficient to induce tumor control by WT CD8+ T cells. Finally, enhanced tumor control was observed in immune-competent mice when fewer than 5% of T cells expressed CA-IKKβ. Our results suggest that NF-κB is at the cross-roads of major T cell fate decisions that uniquely synergize for control of tumor growth and identify a therapeutic pathway with potential clinical applicability.
Polyanhydride nanoparticle vaccine platform delays tumor growth (P2050)
Authors: Darling Ross , Huntimer Lucas , Ross Kathleen , Ramer-Tait Amanda , Narasimhan Balaji , Wannemuehler Michael 
Published: January 2023

Abstract
Immunotherapies designed to direct the immune system to elimate malignancies is a growing area of research aimed at providing a safe and effective alternative and/or adjunct therapy to chemotherapeutic and surgical interventions. These approaches require the development of immunization regimens that induce efficacious cell-mediated immunity directed at antigens expressed by tumor cells. Particles consisting of polyanhydride copolymers based on 1,6-bis(p-carboxyphenoxy) hexane (CPH), and 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctante (CPTEG) have been shown to enhance dendritic cell activation, which in turn induces activation and proliferation of antigen-specific CD4+ and CD8+ T cells in vitro. We demonstrate that immunization of mice with a polyanhydride nanoparticle-based vaccine platform induced a potent immune response to a specific tumor-associated model antigen in order to control tumor progression in vivo. Specifically, we challenge immunized mice with a transgenic tumor cell line, expressing ovalbumin (Ova) as a target antigen, to determine if our vaccination strategy is effective. Mice immunized once with a regimen consisting of soluble Ova and Ova encapsulated in 20:80 CPTEG:CPH nanoparticles exhibited delayed tumor growth during the course of our study when compared to mice immunized with soluble Ova adjuvanted with Alum, soluble Ova alone, or PBS. Mice that receive the nanoparticle formulation also have improved survival rates when compared other formulations.
Acute TLR5 stimulation with a flagellin-derived agonist induces cytotoxic lymphocyte-mediated tumor immunity (P2064)
Authors: Leigh Nicholas , Bian Guanglin , Ding Xilai , Liu Hong , Aygun-Sunar Semra , Burdelya Lyudmila , Gudkov Andrei , Cao Xuefang 
Published: January 2023

Abstract
Toll-like receptor (TLR) mediated recognition of pathogen associated molecular patterns allows the immune system to rapidly respond to a pathogenic insult. This feature makes TLR agonists attractive agents that can stimulate a favorable immune response. CBLB502 is a pharmacologically optimized TLR5 agonist derived from Salmonella enterica flagellin. In this study, we examined the effect of CBLB502 on tumor immunity using two lymphoma models, both of which do not express TLR5, and thus do not directly respond to CBLB502. Upon challenge with the T cell lymphoma RMAS, CBLB502 treatment after tumor inoculation protects approximately 50% of C57BL/6 mice from death caused by tumor growth. This protective effect is both natural killer (NK) cell and perforin dependent. In addition, CBLB502 stimulates clearance of the B cell lymphoma A20 in BALB/c mice in a CD8+ T cell dependent fashion. ImageStream flow cytometry analyses reveal that CD11b+ and CD11c+ cells, but neither NK nor T cells, directly respond to CBLB502 as determined by nuclear translocation of NFκB. NFκB can regulate a variety of pro-inflammatory cytokines; accordingly, CBLB502 increases serum levels of IL-6, IL-15, TNFα, and IFN-γ. Furthermore, CBLB502 promotes antigen-presenting cell maturation as evidenced by CD86 upregulation. These findings demonstrate that CBLB502 can stimulate a robust antitumor immune response by indirectly activating cytotoxic lymphocytes through TLR5-expressing accessory immune cells.
Improving the identification of beneficial mimotopes using a representative tumor-specific T cell receptor (P2066)
Authors: Buhrman Jonathan , Jordan Kimberly , Slansky Jill 
Published: January 2023

Abstract
Vaccination with peptide mimotopes is a promising strategy to improve antitumor immunity. Mimotopes function by eliciting increased numbers of T cells that cross-react with the native tumor antigen. Unfortunately, mimotope vaccines often elicit T cells that do not cross-react or have low affinity for the tumor Ag. Therefore, determining which mimotopes are most effective upon vaccination is a challenge. Using a high affinity tumor-specific T cell clone, we identified a panel of mimotopes for the dominant Ag (AH1) of a mouse colon tumor cell-line (CT26) that elicits a range of tumor protection when used in vaccines. Ex vivo evaluation of the TCRs of T cells initiated by mimotopes that protect against tumor challenge revealed increased representation of a Vβ8.3/Jβ2.6 CDR3 motif. The original high affinity clone was not representative of the tumor-specific TCRs identified. We identified a ‘representative’ clone that made up nearly 8.5% of sequences following immunization with mimotopes. We tested the hypothesis that using a representative TCR to screen peptide libraries would improve the frequency of discovery of efficacious mimotopes. We demonstrated that the representative T cell bound to more protective mimotopes than the high affinity clone by screening genetically encoded peptide libraries and comparing mimotope vaccines identified by each TCR. These results have important implications when determining the optimal mimotopes for cancer immunotherapy.
Targeting miR-23a in CD8+ cytotoxic T lymphocytes for tumor immunotherapy (P2072)
Authors: Lin Regina , Chen Ling , Hu Chunyan , Chen Gang , Jiang Shan , Sevilla Jose , Wan Ying , Zhu Bo , Li Qi-Jing 
Published: January 2023

Abstract
CD8+ cytotoxic T lymphocytes (CTLs) are ideal candidates for tumor immunotherapy. However, the potential of CTL-based cancer intervention has been limited by the challenges of in vitro expansion and the susceptibility of modified CTLs to immunesuppression in vivo. Here, we report a novel microRNA-targeting approach to augment the cytotoxic capacity of tumor-specific CTLs. We have identified miR-23a as a key inhibitor of anti-tumor CTL effector responses in vivo. miR-23a down-regulates its mRNA target Blimp-1, and simultaneously inhibits the expression of the key CTL effector molecules, Granzyme B and IFNγ. Conversely, functional suppression of miR-23a in CTLs augments CTL effector molecule expression, and enhances their cytotoxic potency on a per-cell basis. In mouse models of established B16 melanoma or Lewis lung cancer, immunotherapy with miR-23a-inhibited tumor-specific CTLs dramatically retards tumor growth to confer superior protection against tumor progression in vivo. We further establish that, by suppressing cMyc-mediated inhibition, tumor-derived TGFβ functions as a key enhancer of miR-23a expression in effector CTLs. In human lung cancer patients, elevated miR-23a expression in pleural effusion CTLs correlates with their impaired anti-tumor potential. Our findings not only demonstrate how TGFβ-induced miR-23a may impair CTL function to promote tumor immune evasion, but also provide the first proof-of-principle of a miRNA-based strategy for tumor immunotherapy.
Anti-tumor effects of adoptive transfer inactivated MHC-haploidentical tumor specific lymphocytes in mouse model (P2082)
Authors: Zhang Shuren , Shi Guilan , Liu Binlei 
Published: January 2023

Abstract
In this study, we evaluated effect of tumor-antigen-primed MHC-haploidentical lymphocytes in a TC-1 (H-2b) murine lung cancer model. The haploidentical effector cells prepared from splenocytes stimulated with the tumor cell lysates pulsed-DCs from F1 (C57BL/6 × Balb/C, H-2bd) mice, or immunized from F1 mice vaccinated with inactivated tumor cells. Haploidentical lymphocytes immunized with TC-1 could specifically kill the TC-1 cells, as well as up-regulate the NK activity. The effector cells inactivated with Mitomycin C in vitro kept the killing capacity, and migrated to tumor tissue. Compared with the cells from non-inactivated, or the syngeneic mice, the cells from Mitomycin C inactivated mice with haploidentical showed enhanced tumor inhibition. The survival time increased in tumor bearing mice and some showed tumor free, which developed no tumor after rechallenged with TC-1.Th1 cytokines including IL-2, IFN-γwere significantly increased. These studies demonstrate that the tumor antigen immunized MHC-haploidentical lymphocytes could specificity target to the tumor and kill them. MHC-mismatched alloantigens could be an effective adjuvant to break the immune tolerance and to activate innate and adoptive immunity in the tumor bearing host. The infusion of the inactivated MHC-haploidentical lymphocytes immunized with tumor antigen could be a safe and effective adoptive immunotherapy against tumor.
An IL-33 immunotherapy that blocks tumor growth by establishing innate lymphoid cells. (P2084)
Authors: Kim Wonyoung , Kim Juyang , Moon U-jeong , Jung Soyeon , Cho Hong , Kwon Byungsuk 
Published: January 2023

Abstract
Innate lymphoid cells are recently identified cell population, which produces IL-5, IL-13, and GM-CSF in response to IL-33. These cells play an important role in anti-helminth immunity and allergic diseases. However, little is known about the role of innate lymphoid cells in tumor. We report in this study that sustained intratumoral expression of IL-33 establishes a high numbers of innate lymphoid cells secreting high levels of GM-CSF which are required for inhibition of tumor growth. GM-CSF strongly inhibits proliferation of mural cells (pericytes and smooth muscle cells), thereby preventing normal angiogenesis in tumor mass. Our results identify a previously unrecognized innate immune pathway involving innate lymphoid cells which mediated type-2 innate immunity leading to antitumor activity.
Tumor-derived IL-35 promotes tumor growth by enhancing myeloid cell accumulation and angiogenesis (P2034)
Authors: Bai Xue-Feng , Wang Zhihui , Liu Jin-Qing , Liu Zhenzhen , Shen Rulong , Basu Sujit , Feng Youmei 
Published: January 2023

Abstract
IL-35 is a member of the IL-12 family of cytokines consisting of IL-12 p35 subunit and IL-12 p40-related protein subunit, EBV-induced gene 3 (EBI3). IL-35 functions through IL-35R and has a potent immune suppressive activity. Although IL-35 has been demonstrated to be produced by regulatory T cells, gene expression analysis has revealed that IL-35 is likely to have wider distribution including expression in cancer cells. In this study we have demonstrated that IL-35 is produced in human cancer tissues such as large B cell lymphoma, nasopharyngeal carcinoma and melanoma. In order to determine the roles of tumor-derived IL-35 in tumorigenesis and tumor immunity, we generated IL-35 producing plasmacytoma J558 and B16 melanoma cells, and observed that the expression of IL-35 in cancer cells does not affect their growth and survival in vitro, but stimulates tumorigenesis in both immune competent and Rag1/2 deficient mice. Tumor-derived IL-35 increases CD11b+Gr1+ myeloid cell homing in tumor microenvironment, and thereby promotes tumor angiogenesis. In immune competent mice, spontaneous CTL responses to tumors are diminished. IL-35 does not directly inhibit tumor antigen specific CD8+ T cell activation, differentiation and effector functions. However, IL-35-treated cancer cells had increased expression of gp130 and reduced sensitivity to CTL destruction. Thus, our study indicates novel functions of IL-35 in promoting tumor growth via enhancing myeloid cell accumulation, tumor angiogenesis and suppression of tumor immunity.
Real-time in vivo analysis of T cell migration and activation in the periphery and in the central nervous system using a genetically encoded calcium indicator (P4103)
Authors: Mues Marsilius , Bartholomäus Ingo , Thestrup Thomas , Griesbeck Oliver , Wekerle Hartmut , Kawakami Naoto , Krishnamoorthy Gurumoorthy 
Published: January 2023

Abstract
Interaction of T cells with cells of the surrounding milieu may result in activation of one or both partners. In particular, T cell activation following recognition of antigen presented by antigen presenting cells (APCs) triggers a swift rise of intracellular calcium levels within the T cell. Synthetic calcium indicators have been successfully used to monitor the activation status of T cells in vitro. However, these chemical dyes do not persist intracellularly for a sustained period which creates a major challenge for calcium imaging in the living animal. We now present a newly developed fluorescence resonance energy transfer (FRET)-based, genetically encoded calcium indicator (GECI) expressed in (auto)antigen-specific CD4+ T cells to study T cell activation in vivo at real time. Using two-photon microscopy, we explored the responses of retrovirally transduced, GECI-expressing T cells to antigen. In lymph nodes, the administration of exogenous antigen caused an almost immediate arrest of T cells around APCs concomitant with an instant rise of cytosolic calcium levels. In contrast, encephalitogenic T cells entering the leptomeningeal space, one main portal into the central nervous system parenchyma during experimental autoimmune encephalomyelitis, showed elevated intracellular calcium levels while still meandering through the space. This approach enables us for the first time to follow the migration and activation patterns of T cells in vivo during the course of the disease.
The effects of Trypanosoma cruzi infection and vaccination on priming T. cruzi-specific CD4+ T cells. (P3346)
Authors: Blase Jennifer , Eickhoff Christopher , Zhang Xiuli , Hoft Daniel 
Published: January 2023

Abstract
Trypanosoma cruzi is a protozoan parasite and the causative agent of Chagas disease. The T. cruzi protein trans-sialidase (TS) is currently under investigation as a vaccine candidate. There are defects in CD4+ T cell responses after T. cruzi infection as compared to TS vaccination. We sought to compare T cell receptor transgenic (Tg) TS-specific CD4+ T cell responses induced by infection versus vaccination through RNA microarrays. Tg TSaa57-74-specific CD4+ T cells were purified from naïve transgenic mice and activated in vitro by peptide-pulsed DCs or T. cruzi-infected and peptide-pulsed DCs, as well as in vivo by TS-DNA vaccination or T. cruzi infection. At various time points post activation, RNA was extracted from purified Tg CD4+ T cells and analyzed by microarray. In vitro, infection of DCs resulted in an increase in the expression of the signaling molecule Map3k10, the cytokine Il21, and factors involved in cell death/survival in CD4+ T cells. Following in vivo activation, proliferation was similar among Tg T cells stimulated with TS vaccination and T. cruzi infection. The microarray will reveal genes differentially expressed in response to T. cruzi infection with further analysis ongoing. These in vitro and in vivo studies using our transgenic T. cruzi-specific CD4+ T cells suggest that T. cruzi infection and TS vaccination differentially activate CD4+ T cells which may explain the defects in CD4+ T cells observed following T. cruzi infection.
A role for T-bet in regional responses required to control parasite replication. (P3302)
Authors: Pritchard Gretchen , Hall Aisling , Wagage Sagie , Dupont Christopher , Reiner Steven , Hunter Christopher 
Published: January 2023

Abstract
The role of T-bet, a hallmark transcription factor of Type 1 immune responses, has been examined in a variety of infection models. The results of these studies have been contradictory in that the immune response to some pathogens (e.g. Salmonella, TB) requires T-bet while its expression is dispensable for resistance to other pathogens (e.g. LCMV, Listeria monocytogenes). The intracellular parasite Toxoplasma gondii induces a rapid Type 1 response in mice, characterized by production of the cytokine interferon-γ, which is required for controlling the parasite. In the absence of T-bet, mice challenged with T. gondii develop normal NK responses and have largely intact T cell activity, including production of IFN-γ. However, despite production of IFN-γ by NK and T cells, T-bet deficient mice succumb to acute infection; this increased susceptibility is characterized by control of parasite replication in the liver and peritoneum, but higher parasite burden in other sites. These data suggest local differences in the requirement for T-bet to control parasite replication and reveal an essential function of T-bet in the regional vs. systemic immune response necessary for control of T. gondii.
Th17 cells confer long-term adaptive immunity to oropharyngeal candidiasis (P3308)
Authors: Hernandez-Santos Nydiaris , Huppler Anna , Peterson Alanna , Khader Shabaana , McKenna Kyle , Gaffen Sarah 
Published: January 2023

Abstract
Oropharyngeal candidiasis (OPC) is an opportunistic infection of the oral cavity caused primarily by Candida albicans. OPC particularly afflicts HIV+ patients with low CD4 counts, suggesting a role for CD4+ T cells in host defense. Experimental models of OPC have strongly suggested that immunity to OPC is IL-17-dependent, and humans with rare genetic defects that result in Th17 deficiency are associated with the development of OPC. However, other sources of IL-17 have been described, particularly in the innate compartment, but the relative contribution of adaptive and innate sources of IL-17 during OPC has not been well articulated. Here, we showed that development of adaptive immune responses in OPC results in a ~1 log decrease in fungal burden, tightly associated with an increased frequency of antigen-specific CD4+IL-17+ (Th17) cells. Importantly, adoptive transfer of Candida-primed Th17 cells into Rag1-/- mice resulted in protection from disease. Surprisingly, however, CD4-/- mice were resistant to OPC, which was linked, at least in part, with compensatory IL-17 production by both CD8+ and double-negative (DN) T cells. The adoptive transfer of CD8+IL-17+ or DN cells into Rag1-/- mice resulted in protection from OPC. Therefore, Th17 cells contribute to C. albicans clearance but their absence can be compensated by alternative sources of IL-17. These findings implicate CD8+IL-17+ and DN cells as vaccine targets in immunocompromised populations.
Microfluidic single cell array for dynamic T cell imaging (P3368)
Authors: Hung Paul , Chen Cindy 
Published: January 2023

Abstract
Imaging of individual live cells over time is essential for studying dynamic cellular processes within the heterogeneous cellular population. There is growing interest in using imaging technology to decipher the signaling pathway governing the stimulation of CD4 positive T cells by antigen-presenting cells in order to better understand the associated adaptive immune response. However, there are several technical challenges when conducting time-lapse live cell imaging to study the activation and the differentiation of T cells. First, primary T cells are non-adherent and become highly mobile upon activation. Second, T cell differentiation processes are relatively slow which could take over 72 hours. At last, ability to introduce different reagents as well as a second population of cells to monitor the cellular responses in real time is almost impossible with conventional cell culture substrates. Here we present a microfluidic single cell trapping array platform for dynamic T cell imaging. The platform allows the capture and growth of non-adherent immune cells, long-term monitoring and tracking of cells, separate introduction of antigen presenting cells as well as concurrent imaging with automatic liquid exchange. The protocol to execute each function was developed with a sample experiment demonstrated to screen for cytosolic calcium transients at single cell resolution.
Direct monitoring of phagocytosis and endocytosis in live cells with novel pH-sensing fluorescent dyes. (P3393)
Authors: Langsdorf Chris , Beacham Dan , Jaron Shula , Zhang Yu-Zhong , Janes Mike 
Published: January 2023

Abstract
The basic cellular internalization processes of endocytosis and phagocytosis are important to many areas of cell biology including receptor internalization, pathogen response, and apoptotic cell clearance. However, the ability to study these processes has historically been limited by the lack of quality tools to directly monitor the internalization and acidification of cargo. Here we present an assortment of tools to enable research into cellular internalization pathways with particular relevance to immunology. Two fluorogenic, pH-sensitive probes, one green and one red, are presented. These dyes are non-fluorescent at the neutral pH typically found in the cytosol and extracellular environment, but become brightly fluorescent in acidic cellular compartments, permitting direct monitoring of internalization and acidification processes. We present experimental data in which these dyes were used to label microorganisms including yeast and gram-positive and -negative bacteria. Live cell imaging and flow cytometry were then used to monitor the phagocytosis and acidification of these labeled particles by cultured murine macrophages over time. Additionally, we investigated the utility of these dyes to study phagocytic clearance of apoptotic cells by primary human monocyte-derived macrophages. We anticipate that these tools will enable additional research into the fields of receptor trafficking, drug delivery, host-pathogen response, and clearance of apoptotic cells.