bluuebunny/crossref_metadata_2025_split huggingface dataset:
CD25 signaling via STAT5 is necessary for development of cytolytic CD4 T cells (163.13)
Authors: Brown Deborah , Workman Aspen , Jacobs Ashley , Lee Sarah , Condon Shirley 
Published: January 2023

Abstract
Cytolytic CD4 cells have been identified in vivo during viral infections; however, the factors necessary for driving the cytolytic phenotype have not been characterized. Previously, we found that IL-2 is necessary and sufficient to drive the in vitro differentiation of naïve CD4 cells into cytolytic effectors. To further dissect the role of IL-2 in CD4 CTL generation, TCR transgenic mice deficient in IL-2 production or IL-2Rα (CD25) were used. In vitro, CD25 deficient cells do not express granzyme B (GrB) or acquire cytolytic activity when cultured in the presence of IL-2. In contrast, CD25+/- cells exhibit half maximal expression of GrB and reduced cytotoxicity when compared to WT cells. In vitro, IL-2 activates STAT5 phosphorylation, peaking at 18-24 h, correlating with GrB expression and cytotoxicity by 72-96 h. Inhibition of the JAK3/STAT5 pathway resulted in a dose dependent reduction of GrB expression. Surprisingly, other common γc cytokines such as IL-7 and IL-15 induce STAT5 phosphorylation but do not induce cytotoxicity, most likely due to the timing of STAT5 activation. Studies determining whether STAT5 activation synergizes with other signaling pathways to induce optimal CTL activity are underway. Further, the role of CD25 signaling in the induction of cytolytic activity in vivo during influenza infection will be discussed. These data have implications in the design of vaccines and in adoptive immunotherapy against certain tumors.
T cell proliferative and apoptotic responses in conditional Daxx knockout mice (163.16)
Authors: Li Jinghe , Zhang Jianke 
Published: January 2023

Abstract
Apoptosis is essential for maintaining homeostasis in the immune system. Fas is a single transmembrane domain protein capable of inducing apoptotic death in lymphocytes. Mutations in the Fas receptor or it’s ligand, FasL, lead to autoimmune-lymphocproliferation diseases characterized by lymphadenopathy, splenomegaly and autoantibody production. The Fas-associated death domain (FADD) protein is an adaptor protein which binds to Fas, recruits and activates the initiator caspase 8. In addition to FADD, proteins including Daxx have also been indicated to bind to Fas. It has been proposed that Daxx mediates a parallel apoptotic pathway that is independent of FADD and Caspase 8, but is dependent on ASK1-medaited signaling. Deletion of FADD blocks Fas-induced apoptosis in T and B cells, which, however, does not lead to lymphoproliferation diseases as present in Fas mutant animals. Recent studies indicate that absence of FADD unleashes a potent necrosis-like death pathway. The in vivo function of Daxx in lymphocytes has not been properly analyzed as deletion of Daxx in germ cells lead to embryonic lethality. In this study, we used a conditional mutant mouse in which Daxx is deleted specifically in T cells. Our data revealed a novel function of Daxx in the regulation of proliferation and death in primary T cells.
Localized p:MHCII presentation maintains CD4+ T cell stability and avoids exhaustion (163.19)
Authors: Nelson Ryan , McLachlan James , Jenkins Marc 
Published: January 2023

Abstract
Recent work has demonstrated that memory CD4+ T cells decay following clearance of some acute bacterial infections. However, this issue has not been addressed for persistent bacterial infections where CD4+ T cells are the protective cell type. During persistent Salmonella infection in mice, CD4+ T cells control pathogen burden by activating infected macrophages and limiting bacteria to the gut draining mesenteric lymph nodes. Using a peptide:MHCII (p:MHCII)-tetramer based enrichment strategy, we tracked a polyclonal Salmonella p:MHCII-specific CD4+ T cell response to oral infection. Salmonella p:MHCII-specific T cells expanded and were maintained at a numerically stable level throughout persistent infection but decayed if the infection was cleared. This population consisted of highly functional Th1 cells capable of producing IFN-γ and TNF-α upon re-stimulation. Using adoptive transfer of memory cells into mice persistently infected with Salmonella lacking the relevant peptide, we showed that p:MHCII dependent proliferation by a small number of cells accounted for stable memory. However, transfer of memory cells into transgenic mice systemically expressing the relevant p:MHCII complexes induced high PD-1 expression and functional exhaustion. These results indicate that localized p:MHCII presentation in the chronically infected mesenteric lymph nodes is the key to maintaining this naturally stable CD4+ T cell response to Salmonella and simultaneously avoiding exhaustion.
TGF-β-dependent suppression of IL-22 production in TH17 cells is mediated by the transcription factor c-Maf (163.2)
Authors: Rutz Sascha , Noubade Rajkumar , Eidenschenk Celine , Singh Harinder , Ouyang Wenjun 
Published: January 2023

Abstract
T helper (TH) cells modulate immune responses to better cope with various types of invading pathogens through the production of different effector cytokines. TH17 cells produce Interleukin(IL)-17, and IL-22, and play an indispensable role in host defense against infections of extracellular pathogens. IL-22, a member of the IL-10 cytokine family, enhances proinflammatory innate defense mechanisms from epithelial cells, and provides crucial tissue protection from damages caused by inflammation and infection. Transforming growth factor (TGF)-β differentially regulates IL-22 and IL-17 expression. IL-6 alone promotes T cells to only produce IL-22, whereas the combination of IL-6 with high concentrations of TGF-β results in production of IL-17 but not IL-22. Here we identify the transcription factor c-Maf, which is induced by TGF-β, as a downstream repressor of Il22. c-Maf binds to the Il22 promoter, and is both necessary and sufficient for the TGF-β-dependent suppression of IL-22 production in TH17 cells. While a number of factors, such as RORγt, AhR and BATF, have been identified as positive regulators of IL-22 expression, c-Maf is the first transcription factor shown to be involved in its negative regulation. This is even more surprising since c-Maf at the same time is critical in promoting the expression IL-10 and IL-21 in T cells.
The induction of FoxP3 in naive T cells is dependent upon the transcription factors TFE3 and TFEB. (163.4)
Authors: Bettinger Patricia , Roman Christopher 
Published: January 2023

Abstract
TFE3 and TFEB are members of the basic helix-loop-helix leucine zipper MiTF/TFE (Microphthalmia-associated transcription factor) family of transcription factors. They are ubiquitously expressed in human and murine tissue and form homo- and/or heterodimers to bind the E-box core sequence CAYGTG. Using a transgenic mouse line expressing a trans dominant negative (TDN) inhibitor of TFE3 and TFEB in T cells, we previously showed that CD40L is a key target of both TFE3 and TFEB and that inactivating these molecules causes hyper IgM syndrome. Unexpectedly, we now show that naïve T cells from these mice have a significant defect in the in vitro differentiation into the inducible T regulatory (iTreg) phenotype, demonstrated by reduced induction of the hallmark Treg transcription factor, FoxP3. Although Smad7, a negative regulator of TGFβ signaling, is a target gene of TFE3 in non-lymphoid cells, preliminary results indicate its expression is unaffected in these cells, as is the phosphorylation of Smad3, indicating TGFβ signaling pathway is intact. This suggests TFE3/B are important in Treg differentiation, possibly as direct regulators of the FoxP3 gene. This combined evidence demonstrates a multiplicity of roles for TFE3 and TFEB in T cell function.
Malaria-induced IL-10 contributes to the systemic burden of non-typhoidal Salmonella (164.10)
Authors: Mooney Jason , Butler Brian , Lokken Kristen , Xavier Mariana , Schaltenberg NIcola , Chau Jennifer , George Michael , Dandekar Satya , Luckhart Shirley , Tsolis Renee 
Published: January 2023

Abstract
Non-typhoidal Salmonella serotypes (NTS) in pediatric patients with severe malaria can develop a life threatening bacteremia, a major source of child mortality in Sub-Saharan Africa. Here, we use a mouse model, mimicking severe anemia seen in humans, to address mechanisms by which an underlying malaria infection contributes to the increased risk of NTS bacteremia. Plasmodium yoelli infected red blood cells were administered i.p. in CBA or B6 mice. At peak parasitemia, Salmonella Typhimurium was administered by g.g. in a streptomycin-induced colitis model. Characterization of inflammation to NTS in the cecum was assessed by histopathology, microarray and qRT-PCR. Bacterial loads in systemic tissues were followed up to 4 days post inoculation. Our results indicate that the malaria parasite infection causes a global suppression of proinflammatory responses in the intestine, blunts intestinal neutrophil influx and increases the bacterial burden at systemic sites. Blunting of intestinal inflammatory responses was independent of antibody-induced anemia, but required induction of the immunoregulatory cytokine IL-10. Blocking IL-10 activity reduced systemic NTS in coinfected mice and administration of exogenous IL-10 was sufficient to increase the systemic burden of NTS in the absence of parasite infection. However, an increase in circulating NTS required both anemia and IL-10. Thus, we have identified two factors that synergize to increase bacteremia using a murine model.
Influence of viral specific memory cells on Leishmania major infection (164.12)
Authors: Crosby Erika , Wherry E. , Scott Phillip 
Published: January 2023

Abstract
One of the hallmarks of adaptive immunity is the development of a pathogen specific immune response that is maintained long term. Despite this specificity, an important question is whether these persistent memory cells can influence the immune response to an unrelated infection. Here we utilized lymphocytic choriomeningitis virus (LCMV) and Leishmania major (L. major) as our model infections to investigate the influence of viral specific memory cells on L. major infection. Using a transgenic P14 CD8 T cell transfer system, we assessed the ability of LCMV activated cells to migrate to an L. major lesion. While naïve P14 T cells were unable to migrate to an L. major lesion, P14 T cells from a mouse that had been infected with LCMV 30 days prior migrated readily to the lesion. Having seen that LCMV memory cells were able to enter the lesion, we asked whether viral CD8 memory T cells could influence the course of L. major infection. Mice were infected with LCMV and 30 days later infected with L. major. From 2 weeks post infection on, there was a significant increase in the pathology of the coinfected mice compared to mice infected with L. major alone. Corresponding with the increased lesion size was an increase in the number of CD8 T cells making granzyme, but not IFN-γ, within the lesions of coinfected mice. Ongoing studies are focused on determining the mechanism by which these non-specific memory cells increase the pathology associated with L major infection.
Modulation of immune responses to Clostridium difficile by peroxisome proliferator-activated receptor γ and miRNA-146b (164.14)
Authors: Viladomiu Monica , Hontecillas Raquel , Pedragosa Mireia , Michalak Pawel , Michalak Katarzyna , Guerrant Richard , Roche James , Warren Cirle , Bassaganya-Riera Josep 
Published: January 2023

Abstract
Clostridium difficile is typically a harmless anaerobic bacterium but has recently re-emerged as a pathogen that can cause nosocomial diarrhea, colitis and death. To investigate the role of peroxisome proliferator-activated receptor (PPAR) γ in modulating immune responses to C. difficile we have performed several studies using a mouse model of antibiotic-induced C. difficile-associated disease (CDAD). The loss of PPARγ in T cells increased disease activity, body weight loss, and colonic inflammatory lesions after infection. It also resulted in upregulated IL-17 and MCP-1, and downregulated IL-10 expression, suggesting that a Th17 phenotype predominates during CDAD in mice lacking T cell PPARγ. Treatment of C. difficile-infected mice with PPAR γ agonists ameliorates disease severity and colonic lesions. RNA-seq results in colonic specimens indicated that three miRNAs were significantly overexpressed in infected mice: mmu-miR-146b, mmu-miR-1940, and mmu-miR-1298 (FDR P &lt; 0.05). Real-time PCR results validated that infection results in overexpression of miR-146b, a molecule involved in regulating immunity and inflammation. Furthermore, NCOA4, a co-activator of PPARγ and target of miR-146b, was down-regulated in colons of infected mice. We provide novel evidence supporting a role for PPARγ in regulating C. difficile-related inflammation and immunopathology and explore the potential role of miRNA in modulating host responses to C. difficile.
Probiotics-containing yogurt ingestion modulates systemic cellular and humoral immunity in children (164.20)
Authors: Huang Shu-Ching , Yang Yao-Jong 
Published: January 2023

Abstract
Background: This study aimed to investigate whether short-term probiotics-containing yogurt ingestion benefits to systemic cellular and humoral immunity in healthy schoolchildren. Methods: Healthy schoolchildren aged 4-12 years without major systemic or allergic history were studied. Subjects had diarrheal diseases or taken antibiotics within one month were also excluded. The Ethical Committee of our institute has approved our study design (ER-98-050). All of them have provided the serum samples before and after 4-week ingestion of probiotics-containing yogurt. The serum samples were tested for the TNF-α, IL-17, IL-10, IL-6, Immunoglobulin (Ig) A, G, and E levels. Results: A total of 60 children completing at least 80% consumption of total designed amount of yogurt were enrolled. Their mean age was 9.3±1.6 years with a female to male ratio 0.54. For systemic cytokines production, yogurt ingestion significantly decreased serum IL-6 level (12.8±4.2 vs. 24.2±6.3 pg/ml, P = 0.002) and marginal significantly increased TNF-α (66.4±14.6 vs. 44.5±10.9 pg/ml, P = 0.11). For immunoglobulin levels, children consumed yogurt can significantly increase serum IgA level (178.8±8.2 vs. 167.1±7.9 mg/dl, P = 0.001). However, yogurt consumption did not affect the levels of IL-17, IL-10, IgG, and IgE. Conclusions: Short-term probiotics-containing yogurt ingestion benefits on an increment of serum IgA and decrease of IL-6 levels in healthy schoolchildren.
Differential regulation of pathogenesis and immune reactions in C57BL/6 and CBA/N mice infected with Clonorchis sinensis (164.22)
Authors: Jin Yan , Wi Hae Joo , Choi Min-Ho , Hong Sung-Tae , Bae Young Mee 
Published: January 2023

Abstract
The current knowledge of immunological response to clonorchiasis, a major Asian endemic helminthic disease, is insufficient. To develop a mouse model of clonorchiasis, CBA/N and C57BL/6 mice were infected with Clonorchis sinensis metacercariae and analyzed host responses at 2, 4, and 8 weeks post infection. CBA/N mice infected with C. sinensis developed more severe gross and histopathological changes than C57BL/6 mice. In addition, more pronounced inflammatory cell infiltration and hepatocyte necrosis were noticed in CBA/N mice, especially at 2 weeks post-infection. Serum biomarkers of liver injury (ALT and AST) were increased significantly in CBA/N mice after C. sinensis infection as compared with those of C57BL/6 mice. We also analyzed the proliferation of splenocytes stimulated with crude C. sinensis antigen and cytokine production in the culture supernatant of activated splenocytes. We found that splenocytes from CBA/N mice were highly proliferative and the IL-17 level was increased. Additionally, an increased IL-4 level was sustained until 8 weeks post-infection in CBA/N mice. The serum levels of C. sinensis-specific IgG1 and IgG2a were increased in CBA/N mice, whereas IgE was increased in C57BL/6 mice. Furthermore, the level of IL-17 was increased in intrahepatic lymphocytes in CBA/N infected groups. Present study suggest that CBA/N could be a appropriate mouse model for clonorchiasis and might be useful for studying early immune responses in liver fluke infection.
Identifying host genes that determine disease outcome to Toxoplasma infection through expression QTL analysis (164.23)
Authors: Jensen Kirk , Hassan Musa , Hu Kenneth , Boedec Erwan , Saeij Jereon 
Published: January 2023

Abstract
Disease outcome is significantly influenced by one’s genetic background. Here we explore the genetic basis for differences in host susceptibility to infection with Toxoplasma, an orally acquired parasite that chronically infects 2 billion people worldwide. The survival of 30 recombinant inbred (RI) mouse strains, derived from crosses between susceptible C57BL/6 and resistant A/J mice, following oral challenge with Toxoplasma has previously been reported and genetic loci on mouse chromosomes 1, 9, 11 and 15 control susceptibility. However, it is not clear what genes within these loci predispose B6 mice to infection. To identify genes within these loci that determine disease outcome, we sequenced the RNA of bone marrow derived macrophages from each RI mouse strain after Toxoplasma infection or TNFα + IFNγ stimulation. The macrophage cell type was chosen because it elicits many of the host’s immuno-regulatory and toxoplasmacidal mechanisms following oral infection and/or cytokine stimulation. The gene expression of each gene was considered a quantitative trait (expression QTL) that was subsequently mapped to mouse genetic loci. By analyzing both trans- and cis-regulation of gene expression, key regulators of the macrophage response to cytokine stimulation was uncovered, including the differential expression of a single candidate gene that correlates well with host susceptibility loci on mouse chromosomes 3, 9 and 15. Results from ongoing experiments will be discussed.
Treatment with Lm-LLO immunotherapies lead to decreased Tregs and MDSC in the tumor microenvironment (165.12)
Authors: Singh Reshma , Malinina Inga , Ramos Kimberly , Wallecha Anu 
Published: January 2023

Abstract
Bioengineered Listeria monocytogenes (Lm), which secrete antigens fused to a fragment of listeriolysin O (LLO) have been shown to be effective cancer immunotherapeutics in several mouse models of cancer, and are currently being evaluated in Phase 2 clinical trials for HPV-associated dysplasia and malignancies. Treatment with Lm-LLO immunotherapies results in a marked increase in tumor infiltrating lymphocytes, in particular CD8+T cells. The antigen-specific CD8+T cells have been observed to kill tumor cells in vitro, showing the functionality of the Lm-stimulated T cells. Lm-LLO immunotherapies also have an impact on suppressor cells in the tumor microenvironment. In various tumor models, treatment results in a decrease in the ratio of regulatory T cells (Tregs) to effector T cells in the tumors. Here, we report a corresponding decrease in the ratio, and number, of monocyte-derived suppressor cells (MDSCs) after Lm-LLO immunotherapy. These change are only seen in the tumor microenvironment. Further, both Tregs and MDSCs isolated from the tumor have a decreased ability to suppress the division of T cells after Lm-LLO immunotherapy. However, there is no change in functional ability of splenic Tregs or MDSCs. Thus, the efficacy of Lm-based immunotherapies on tumors is likely due to a combined increase in antigen-specific effector cells and a tumor specific decrease in the numbers and function of suppressor cells in the tumor microenvironment.
Intracellular signaling “fingerprint” in CD4 T cells in response to vaccination (165.14)
Authors: Reichenbach Dawn , Finn Olja 
Published: January 2023

Abstract
Early biomarkers of vaccine efficacy need to be established. We hypothesize that intracellular signaling within CD4 T cells as early as 24 and 48 hours post vaccination could yield a “fingerprint” that is predictive of the ultimate effectiveness of the elicited immune response. In our model, there are reduced responses to MUC1 peptide (MUC1p) vaccination in T cells in human MUC1 transgenic mice (MUC1.Tg) mice compared to wildtype (WT) mice. We are examining phosphorylation downstream of TCR, cell survival, proliferation, and apoptosis signaling cascades post vaccination with either DC loaded with MUC1p (DC:MUC1p) or soluble MUC1p in conjunction with poly:ICLC (sMUC1p:ICLC). Adoptively transferred TCR transgenic CD4 T cells specific for MUC1p displayed no statistically significant differences in signaling during priming in WT vs MUC1.Tg mice at 1, 6, 12 and 24 hrs post vaccination with DC:MUC1p. However, there were trends towards decreased phosphorylation in STAT1, STAT4, and increased pLCK in WT mice. We are currently examining signaling differences in the endogenous memory response in MUC1.Tg and WT mice 1 and 24 hrs post secondary boost of either DC:MUC1p or sMUC1p:ICLC vaccines to determine if differences exist upon secondary exposure and if signaling can be altered. Vaccinated MUC1.Tg and WT mice have been challenged with B16.MUC1 to correlate early T cell signaling with control of tumor burden and intracellular signaling occurring in the tumor microenvironment.
Novel cancer immunotherapy using rational combinations of B7-H1 blockade, Treg depletion and estrogen receptor beta signaling (165.17)
Authors: Curiel Tyler , Kious Mark , Sun Lishi , Vadlamudi Ratna , Hurez Vincent , Murthy Kruthi 
Published: January 2023

Abstract
We recently showed that B7-H1 blockade in mouse models for B16 melanoma and ID8 ovarian carcinoma worked better in females versus males through reduced regulatory T cell (Treg) function. We now show that B7-H1 blunts estrogen-mediated mTOR activation in differentiating Tregs as the mechanism. When we differentiated naïve CD4+ T cells into Tregs in vitro, estrogen reduced Treg numbers and function only if B7-H1 was blocked. The effect was equivalent in males and females. Treg depletion for cancer immunotherapy is promising but hampered by rapid Treg regeneration. Because estrogen signals reduced Treg generation when B7-H1 was blocked, we hypothesized that B7-H1 block during therapeutic Treg depletion would improve clinical efficacy of either individual approach, and that estrogen signals would further boost combination effects. We then showed that estrogen effects were through estrogen receptor beta, suggesting that estrogen receptor beta agonists (in human clinical trials with promising results) could boost Treg depletion with B7-H1 blockade as cancer immunotherapy. In a proof-of-concept experiment, in B16 melanoma challenge, estrogen improved tumor resistance in B7-H1 KO males but not WT males through reduced Treg function. B7-H1 blockade plus estrogen also improved anti-CTLA-4 effects, suggesting rational combinations of immune blockade, Treg depletion and estrogen signals as novel cancer immunotherapies.