bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular control of human regulatory T cell suppression for tumor immunotherapy (P2106)
Authors: Peng Guangyong , Ye Jian , Hsueh Eddy , Zhang Qunyuan , Ma Chunling , Zhang Yanping , Varvares Mark , Hoft Daniel 
Published: January 2023

Abstract
Immunotherapy is a promising approach for treating patients with malignant tumor, but immunosuppressive microenvironments induced by regulatory T cells (Tregs) present a major barrier to successful anti-tumor immunotherapy. A better understanding of the suppressive mechanisms utilized by Tregs is essential for the development of novel strategies to treat human cancer. Here we report that human Tregs can induce senescence in responder naïve and effector T cells in vitro and in vivo. Senescent responder T cells induced by human Tregs changed their phenotypes and cytokine profiles, and possessed potent suppressive function. Furthermore, Treg-mediated molecular control of senescence in responder T cells was associated with selective modulation of p38 and ERK1/2 signaling and cell cycle regulatory molecules p16, p21 and p53. We further revealed that human Treg-induced senescence and suppressor function could be blocked by TLR8 signaling and/or by specific ERK1/2 and p38 inhibition in vitro and in vivo in animal models. Our studies identify a novel mechanism of human Treg cell suppression that induces targeted responder T cell senescence, and provide new insights relevant for the development of strategies capable of preventing and/or reversing Treg-induced immune suppression for tumor immunotherapy.
Vγ9+ γδ T cells of glioblastoma multiforme (GBM) patients expanded ex vivo kill GBM cell lines and secrete IFNγ in vitro, suggesting their therapeutic potential. (P2108)
Authors: Bank Ilan , Peshes-Yaloz Naama , Garelick Daniella , Cohen Zvi , Malina -Marcu Victoria 
Published: January 2023

Abstract
GBM is the most common primary malignant brain tumor, carrying an ominous prognosis (&lt; 2 years survival).Vγ9+ γδ (Vγ9+) T cells mediate major histocompatibility non restricted killing of tumor cells, suggesting Vγ9+ T cell- mediated adoptive immunotherapy may be of benefit in this disease. We established a protocol for ex-vivo expansion of Vγ9+ T cells from the peripheral blood (PB) of GBM patients, in whom Vγ9+ T cells consisted 0.55±0.58%(n=16) of the PB mononuclear cells (MC) just prior to surgical resection of the tumor (vs 0.91±0.42% in 9 healthy donors (HD), p&lt;0.08). We found no correlation between % Vγ9+ T cells in patient PBMC and survival following surgical removal of the tumor. Nevertheless, short term culture of PBMC in the presence of a bisphosphonate, zoledronate (2μM) and 100 IU IL-2, expanded Vγ9+ T cells of all patients 522±466 fold, to consist 54±21% of the cultured MC (not significantly different from HD). The cultured cells were cytotoxic and expressed cytokines in response to GBM cell lines and autologous tumor derived cells. Furthermore, pre-treatment of the tumor with zoledronate, as well as with the clinical anti-GBM reagent temozolomide (TMZ), enhanced Vγ9+ T cell tumor recognition. These data suggest that adoptive immunotherapy employing autologously derived ex vivo activated and expanded Vγ9+T cells, in combination with zoledronate andTMZ, may lead to enhanced therapeutic responses in GBM patients.
An agonist of Toll-like receptor 5 sustains hepatic natural killer and dendritic cell recruitment to the liver while eliciting anti-cancer effects against liver metastases (P2110)
Authors: Brackett Craig , Kojouharov Bojidar , Gitlin Ilya , Johnson Christopher , Burdelya Lyudmila , Gudkov Andrei 
Published: January 2023

Abstract
Toll-like receptors (TLRs) are key components of innate immunity that act as sensors of conserved microbial patterns. To elucidate the mechanisms behind differences in physiological responses mediated by different TLRs, we compared tissue specificity of NF-κB activation in mice by agonists of three cell-surface TLRs: TLR5 agonist CBLB502, a pharmacologically optimized Salmonella flagellin derivative; TLR4 agonist, LPS; and TLR2/6 agonist CBLB612, a mycoplasma lipopeptide mimic. While the liver was defined as a major primary target organ of all three TLR agonists, the cellular response to each agonist was distinct. Thus, liver hepatocytes directly respond to TLR5 and TLR2/6 but not to TLR4, while Kupffer macrophages respond to TLR2/6 and TLR4 but not to TLR5 agonists. Mobilization of NK and DCs to the liver was transient (&lt;24 h) in response to CBLB612 and LPS and sustained (&gt;120 h) following CBLB502 administration. Differences in the liver innate immune response to these three TLR agonists are likely a reflection of cell type-specific expression and differences in molecular mechanisms triggered by different TLRs. Durable hepatic NK cell response by CBLB502 elicits strong TLR5 agonist-dependent effects against colon and breast cancer liver metastases. These long-lasting, TLR5-mediated changes within the liver provide important groundwork for further clinical development of CBLB502, which is currently in clinical trials as a potential radioprotector and immunotherapeutic agent.
Meningeal mast cells facilitate effector T cell function in a murine model of multiple sclerosis. (P4095)
Authors: Walker- Caulfield Margaret , Brown Melissa 
Published: January 2023

Abstract
Experimental autoimmune encephalitomyelitis (EAE) is a rodent model of the CNS demyelinating disease, multiple sclerosis. In EAE, autoreactive T cells are the major orchestrators of myelin damage. Recent data suggests that after priming in secondary lymphoid organs, these T cells are reactivated prior to entry into the CNS. This reactivation is thought to enhance effector function, however the details describing this mechanism are lacking. The meninges, tissues surrounding the CNS, have recently been appreciated as sites of immune responses in early EAE. Mast cells (MCs) residing in the meninges are activated within a day of disease induction and release neutrophil recruitment factors essential for the generation of severe disease. T cells also traffic to the meninges in early EAE suggesting the potential for T cell-MC interactions. Within 24 hours of adoptive transfer, MOG-specific effector CD4+ T cells accumulate in the meninges, an event dependent on the presence of MCs, and acquire the ability to produce the encephalitogenic cytokine, GM-CSF. T cell transfer also results in meningeal MC production of IL-1β. In vitro, co-culture of effector T cells with either wild type or IL-1β-/- MCs confirm that T cells can directly stimulate IL-1β production by MCs, which in turn elicits T cell expression of GM-CSF. These data support the concept that T cell-MC interactions in the meninges facilitate the acquisition of pathogenic effector functions necessary for severe disease.
Autoimmune linkage between the gut and the central nervous system (P4123)
Authors: Mindur John , Boppana Sridhar , Hong Derek , Ito Naoko , Ito Kouichi 
Published: January 2023

Abstract
Multiple sclerosis is an autoimmune disease that causes demeylination and axonal loss in the central nervous system. Although immune-linkage between the central nervous system and the gut is not well understood, recent studies indicated that activation of myelin-specific T cells by commensal bacteria initiated the development of autoimmune diseases in the central nervous system, suggesting that there is an autoimmune linkage between the gut and the central nervous system. We found that golli-myelin basic protein is expressed in the gut epithelial cells and myelin basic protein-specific T cells develop in the gut of transgenic mice expressing the HLA-DR2a and myelin basic protein-TCR genes. We also found that commensal bacteria-derived peptides can serve as an agonist/antagonist of HLA-DR2a-restricted myelin basic protein-specific T cells. This data suggests that commensal bacteria may play an important role in the development of myelin-specific pathogenic T cells.
Changes in CD4+ T cell affinity for MOG do not correlate with symptom relapse or remission in secondary progressive demyelinating disease (P4109)
Authors: Kersh Anna , Evavold Brian 
Published: January 2023

Abstract
We investigated the role of CD4 T cell frequency and affinity in the nonobese diabetic (NOD) mouse model of EAE. This model is clinically relevant in its MHC-class II-associated proclivity to autoimmune disease and its tendency to follow a secondary progressive disease course that resembles that seen in the majority of MS patients. Using the NOD model, we quantified the affinity of CD4 T cells for myelin oligodendrocyte glycoprotein (MOG) at initial peak of disease, symptom remission and at chronic disease time points. We used the micropipette adhesion frequency assay to obtain a sensitive and physiologically relevant two dimensional measurement of T-cell receptor affinity for peptide:MHC in a cell-anchored system. This assay allows us to quantify both frequency and affinity of antigen-specific CD4 T cells that are minimally detected by MHC-class II tetramer-based assays. Our data demonstrated that CD4 T cells isolated from the CNS at the initial peak of disease have similar affinities to those isolated at remission and chronic time points. However, CNS-infiltrating Tregs were roughly twice as frequent at disease remission as compared to initial peak of disease (p&lt;0.0001). Additionally, changes in the distribution of cytokine-producing CD4 T cells seemed to contribute to the remission of symptomatic disease. Thus, Treg frequency and effector cytokine profile determined remission and relapse of symptoms and this progression was independent of changes in T cell affinity.
Role of superantigens in methicillin-resistant Staphylococcus aureus pneumonia (P3314)
Authors: Parker Dane , Prince Alice 
Published: January 2023

Abstract
Staphylococcus aureus is an important cause of respiratory infection in both hospital and community settings. T cells have been found to contribute significantly to pathology after USA300 MRSA pulmonary infection. We postulated this response was due to superantigens. USA300 expresses the superantigens SEK and SEQ. In response to S. aureus USA300 infection in C57Bl/6J mice we demonstrate significant activation of CD4+ T cells in the lung (CD25, CD69 and CD134 activation markers), mediastinal lymph nodes (CD69, 2.38 to 12.56%, P&lt;0.01), and selective activation of CD4+ T cells expressing Vbeta 8.1/8.2 and 8.3, a pattern consistent with staphylococcal superantigens. Similar activation was also observed in human cells. Sterile bacterial supernatant significantly upregulated CD25 (1.7 vs 87%) and CD69 (1.1 vs 55%) (P&lt;0.001) in the Jurkat human T cell line after 24 h of exposure and analysis of Vbeta chain expression in peripheral blood monocytic cells (PBMC) with supernatant showed selection of Vbeta 5, 6, 18 and 21 (4, 24, 5 and 8-fold increases respectively). This pattern of Vbeta expression is consistent with the known patterns for the superantigens SEK (5 and 6) and SEQ (5, 6 and 21). Our data from these models of acute infection indicate the interaction between S. aureus superantigens and T cells contributes significantly to pulmonary pathology. Modulation of the T-cell response to S. aureus may provide a therapeutic option to improve outcomes in a clinical setting.
Involvement of IL-17A-producing TCR γδ T cells in late protective immunity against pulmonary mycobacterial infection (P3324)
Authors: Umemura Masayuki , Touyama Seigo , Fukui Masayuki , Yahagi Ayano , Nakae Susumu , Iwakura Yoichiro , Matsuzaki Goro 
Published: January 2023

Abstract
Interleukin (IL)-17A is a cytokine originally reported to induce neutrophil-mediated inflammation and anti-microbial activity. The CD4+ TCR αβ+ T cells which produce IL-17A have been well characterized as Th17 cells. On the other hand, IL-17A-producing TCR γδ+ T cells have been reported to participate in the immune response at an early stage of infection with intracellular bacteria such as Listeria monocytogenes, Mycobacterium bovis bacilli Calmette-Guérin (BCG) and M. tuberculosis in mice. However, the involvement of IL-17A in protective immunity was not clearly demonstrated in the chronic stage of M. tuberculosis-infected mice. In this study, we found that TCR γδ+ T cells are a primary source of IL-17A, but that mycobacterial antigen-specific Th17 cells were hardly detected even at the chronic stage of M. tuberculosis infection. IL-17A-deficient mice showed a decreased survival rate, and increased bacterial burden in the lungs, livers and spleen on days 30, 60, 90 and 120 after the infection when compared to the wild-type C57BL/6 mice. Furthermore, a histological analysis showed an impaired granuloma formation in the infected lungs of IL-17A-deficient mice, which was considered to be due to a decrease of IFN-γ and TNF at the chronic stage. These data suggest that the IL-17A-producing TCR γδ+ T cells, rather than the Th17 cells, in the infected lungs are an indispensable source of protective immunity against M. tuberculosis infection.
CD36 regulates the malaria-induced pro-inflammatory cytokine responses and activation of NK and T cell by dendritic cells (P3298)
Authors: Gowda D. Channe , Gowda Nagaraj , Wu Xianzhu 
Published: January 2023

Abstract
In falciparum malaria, the scavenger receptor CD36 plays multiple roles: (i) mediates the sequestration of parasites in the microvascular endothelia through the adherence of parasite-infected erythrocytes, (ii) supports phagocytic clearance of parasites by macrophages, and (iii) modulates immune responses to parasites. While the function of CD36 in the parasite sequestration and clearance has been extensively studied, its role in malaria immunity remains poorly understood. We studied the role of CD36 in cytokine responses to malaria parasite, Plasmodiun falciparum, by DCs and in DC function. Blocking of CD36 with anti-CD36 antibodies resulted in the substantial decrease in the levels of infected erythrocyte internalization and pro-inflammatory cytokine responses by DCs. Consistent with these results, DCs deficient in CD36 internalized lower levels of infected erythrocytes and produced decreased levels of pro-inflammatory cytokines. The observed CD36-depedent internalization and cytokine responses by DCs are evident at relatively low doses of infected erythrocytes; at higher doses, the contribution of CD36 become masked due to the increased rate of infected erythrocyte uptake by various other receptor-mediated phagocytosis. Furthermore, IFN-γ production by NK and T cells incubated with IRBC-internalized DCs was dependent on CD36. Overall, our data demonstrate that CD36 plays a critical role in the development of immunity to malaria.
Neonatal thymectomy prolongs the permeability of enteric antigens and promotes the strong activation of peripheral CD4 T cells (P3258)
Authors: Frimpong-Boateng Kwesi , Surh Charles 
Published: January 2023

Abstract
Thymectomy (Tx) during the neonatal period (days 2 to 4) leads to the development of a spectrum of organ-specific autoimmune diseases in several strains of adult mice. The etiology of this intriguing phenomenon is yet to be fully elucidated, although it is widely believed to be a consequence of two controversial mechanisms: (1) production of pathogenic CD4+ T cells from neonatal-specific defect in central tolerance, and (2) abolition in the production of regulatory T cells (Tregs), which are believed to develop later in ontogeny than typical T cells. We hereby suggest an additional mechanism that may contribute to the onset of autoimmunity, perhaps by instigating the chronic activation of autoreactive T cells. We found that neonatal C57BL/6 mice display a defect in their ability to induce efficient tolerance to enteric antigens during the first several days of their life, and neonatal thymectomy significantly prolongs the period of this defect. Hence, while enteric antigens induce strong activation of peripheral CD4+ T cells only during the first several days in euthymic neonatal mice, such responses continue for several weeks in d3 thymectomized mice. The unregulated responses to enteric antigens in return may lead to inadvertent activation of autoreactive T cells.
Intestinal Lin-c-Kit+NKp46-CD4- population highly produces IL-22 upon IL-1β stimulation (P3260)
Authors: Lee Youngae , Kumagai Yutaro , Jang Min Seong , Kim Jung-Hwan , Yang Bo-Gie , Akira Shizuo , Jang Myoung Ho 
Published: January 2023

Abstract
Small intestinal innate lymphoid cells (ILCs) regulate intestinal epithelial cell homeostasis and prevent pathogenic bacterial infections by producing IL-22. NKp46+ ILC (ILC22) and CD4+ ILC (CD4+ LTi) are known as main sources for IL-22 in the small intestine. We found that Lin-c-Kit+NKp46-CD4- (CD4- LTi), ILC22, and CD4+ LTi cells comprised 0.30 ± 0.03%, 1.10 ± 0.12%, and 0.07 ± 0.01%, respectively, of the total lymphocytes in the small intestinal lamina propria of adult mice (BALB/c). We next compared the induction of IL-17F and IL-22 among CD4- LTi, ILC22, and CD4+ LTi cells under stimulation with IL-1β or IL-23 or IL-1β and IL-23 stimulation, by real-time PCR, Bio-Plex analysis, and intracellular staining. We found here that CD4- LTi cells that expressed RORγt and IL-7Rα strongly expressed the transcripts for Il17f and Il22, and produced the proteins for IL-17F and IL-22 after stimulation with IL-1β and IL-23 stimulation compared with ILC22 and CD4+ LTi cells. However, none of CD4- LTi, ILC22, and CD4+ LTi cells produced IL-17F and IL-22 after stimulation with Pam3CSK4 (TLR2 ligand), Poly(I:C) (TLR3 ligand), or LPS (TLR4 ligand) for 24 hrs. Taken together, these findings indicate that the Lin-c-Kit+NKp46-CD4- population may control intestinal homeostasis and provide intestinal protection by producing high levels of IL-17F and IL-22 under the stimulation with IL-1β and IL-23.
Tlr4 regulates IFNγ and IL-17 production by both natural and induced Foxp3+ Tregs in the inflamed intestine during intestinal inflammation (P3276)
Authors: Cao Anthony , Yao Suxia , Stefka Andrew , Qin Hongwei , Elson Charles , Nagler Cathryn , Cong Yingzi 
Published: January 2023

Abstract
Both natural Treg and induced Treg play crucial roles in maintaining intestinal homeostasis. Paradoxically, significant numbers of Foxp3+Treg accumulate in the inflamed lesions in experimental colitis and IBD patients. Treg production of the effector cytokines IFNγ and/or IL-17 may explain their ineffectiveness in suppressing intestinal inflammation. However, it is unknown whether both iTreg and nTreg produce effector cytokines, and how TLR signaling regulates this process. We report here that Foxp3+Treg cells were increased in the intestines of TLR4-/- mice and colitic IL-10-/- mice. Deficiency in both TLR4 and IL-10 resulted in more severe colitis and further increased Treg cells in the inflamed intestines. The majority of Tregs in spleen are Fox3+ Helios+ Npn1+ nTreg whereas most Tregs in intestinal LP are Fox3+ Helios- Npn1- iTreg. Unexpectedly, more nTreg expressed IFNγ and/or IL-17 than iTreg in both spleen and intestine, which was further increased with TLR4 deficiency and intestinal inflammation. LPS-TLR4 signaling in both T cells and APC inhibited Foxp3+Treg via MyD88-dependent, TRIF-independent pathway, which was negatively regulated by SOCS3. These data demonstrate that intestinal inflammation drives iTreg expansion and induces effector cytokines by both nTreg and iTreg. TLR4 not only regulates intestinal inflammation, but also Treg conversion into Th1 and/or Th17. Further, both nTreg and iTreg phenotypes exhibit plasticity in the inflamed intestinal environment.
Dimethyl fumarate stimulates cyclic AMP production and suppresses production of pro-inflammatory mediators in immune cells (P5143)
Authors: Salinthone Sonemany , Wilkinson Amelia , Carr Daniel 
Published: January 2023

Abstract
Multiple Sclerosis (MS) is a disease of the central nervous system that is characterized by chronic inflammation, demyelination, axonal damage and loss of oligodendrocytes. Current FDA approved therapies are only partially effective, have side-effects and are costly. Thus, there is a need for development of novel treatment alternatives for MS. Of interest is the investigational drug BG-12, also known as dimethyl fumarate (DMF). A phase III clinical trial showed that treatment with BG-12 reduced the annual relapse rate by 53% and decreased disability by 38%. Additionally, BG-12 reduced the number of gadolinium-enhancing lesions by 90%. However, the mechanisms of action of BG-12 are not fully understood. BG-12 is an activator of the nuclear factor (erythroid-derived 2)-like 2 (NRF2) transcriptional pathway. To determine if BG-12 is able to activate other signaling cascades, we treated human peripheral blood mononuclear cells with DMF. We discovered that DMF stimulates cAMP production by approximately 3.5 after 1 minute treatment in vitro. DMF also suppresses the production of interleukin (IL)-2, IL-17, regulated and normal T cell expressed and secreted (RANTES) and tumor necrosis factor (TNF)-α in these cells. Furthermore, inhibitor studies indicate that adenylyl cyclases mediate DMF induced cAMP production. These novel findings suggest that DMF may inhibit immune cell function via the cAMP signaling pathway and has implications for MS therapy.
Regulation of 4-1BBL-mediated inflammation at the late phase of TLR response (P1228)
Authors: Kang Young , Ma Jianhui , Shim Eun-Jin , Lu Jiawei , Eun So-Young , Croft Mick , Tobias Peter , Takeuchi Osamu , Akira Shizuo , Han Jiahuai , Karin Michael 
Published: January 2023

Abstract
Toll-like receptor (TLR)-mediated signaling leads to the expression of inflammatory genes, and this process is sustained for the duration of inflammatory response. The TNF superfamily member 4-1BB ligand (4-1BBL) plays an essential role in sustained TNF production in macrophages. 4-1BBL expression was induced by the initial TLR signaling, and 4-1BBL formed a complex with TLRs at a late phase to trigger the secondary signaling. TLR/4-1BBL-mediated late phase signaling was dependent on TIRAP and IRAK2, and the downstream TRAF6/TAK1/TAB1 complex formed and induced MAPK activation. During the early phase of TLR4 response, the TLR4, MyD88, TIRAP, and IRAK2 formed an initial complex, and then the secondary TLR4/4-1BBL/TIRAP/IRAK2 complex formation was followed to initiate the late phase signaling that sustains TNF production in macrophages. Inhibition of the late phase TIRAP activity downregulated sustained TNF production in macrophages and further ameliorated LPS-induced septic shock. Thus, the late phase TLR/4-1BBL/TIRAP/IRAK2 signaling is critical for sustained inflammation in innate immune cells.