bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of tumor-associated antigen (TAA)-specific T cell responses in heavily-tolerized mice requires vaccination with peptide variants that target T cells with decreased responsiveness to TAA (131.7)
Authors: Kemmler Charles , Slansky Jill 
Published: January 2023

Abstract
Vaccination with peptide variants of a tumor-associated antigen (TAA) can induce T cell responses that cross-react with the TAA. Using the gp70(423-431, AH1) epitope of endogenous MuLV as our model TAA, we have developed peptide variants that, unlike AH1 itself, induce AH1-reactive T cell responses upon vaccination of BALB/c mice. Two of these variants, A5 and 39, induce robust AH1-reactive responses in young mice. These variants were used to vaccinate aging mice, which have increased expression of and tolerance to gp70 protein. Variant-39 consistently induced AH1-specific responses, regardless of levels of gp70 expression in individual mice. Conversely, variant-A5 did not induce AH1-specific responses in most aging mice tested. The inability of variant-A5 to induce AH1-specific responses in individual mice correlated with increased gp70 expression. We hypothesized that variant-39 expands AH1-specific cells that are less reactive to AH1 than those expanded by variant-A5, thus impeding tolerance by peripheral AH1 presentation. Analyzing variant-induced responses in young mice, we determined that T cells expanded by variant-39 indeed have diminished function upon stimulation with AH1 relative to those elicited by variant-A5. These findings suggest that tumor vaccines require TAA variants that target cross-reactive T cell repertoires with low enough reactivity to TAA to avoid tolerance in the periphery, yet sufficient reactivity to provide effective antitumor responses.
Homeostatic Proliferation (HP) induced CD8+ T cell memory is regulated by the energy sensitive kinase; mTOR (132.17)
Authors: Li Qingsheng , Rao Rajash , Shrikant Protul 
Published: January 2023

Abstract
The cell intrinsic mechanisms guiding Homeostatic Proliferation (HP) leading to CD8+ T cell expansion and functional maturation for memory remain unclear. We demonstrate that lymphopenia induced naïve CD8+ (OT-I) T cell proliferation (HP) and clonal expansion requires IL-7 induced mTOR activation. Moreover, HP-induced mTOR enhances T-bet expression for functional maturation; IFNg and CTL activity, as well as expression of CD122 to facilitate IL-15 dependent memory generation. Surprisingly, rapamycin mediated mTOR blockade inhibits HP-induced clonal expansion and functional maturation, but promotes memory generation; in an IL-15 independent manner. However, the generation of CD8+ memory by either pathway produces tumor immunity. These results demonstrate that mTOR is a central regulator of HP-induced CD8+ T cell memory generation and indicates that HP-induced memory but not clonal expansion and functional maturation are essential for tumor immunity. Supported by: NIH RO1 CA104645, Alliance Foundation of Roswell Park and OCRF (to PAS)
T-independent antigens induce the formation of long-lived plasma cells (132.18)
Authors: Bortnick Alexandra , Quinn III William , Cancro Michael , Allman David 
Published: January 2023

Abstract
Long-lived plasma cells (PCs) are terminally differentiated B cells that reside in the spleen and bone marrow where they secrete antibody for a life-time. Although PCs are the cellular arbiters of humoral immunity, the signals required for formation of long-lived antibody secreting PCs remain poorly defined. In addition, how long-lived PCs resist apoptosis in response to ionizing radiation (IR) is also not understood. We find that resistance to IR-induced apoptosis occurs exceptionally early, within three days, during PC differentiation. IR-resistance is even established in PCs following immunization with NP-LPS, a type 1 thymus-independent (TI-1) antigen thought to generate only short-lived PCs. We have exploited this finding by administering IR in vivo to investigate the lifespan of antigen-specific NP-LPS induced PCs months after immunization. Contrary to current models, we find immunization with NP-LPS, a response which neither requires T-cell help nor elicits germinal center formation, is sufficient to drive the formation of long-lived IR-resistant PCs. Further, we find that resistance to IR-induced apoptosis is a cell intrinsic property unique to PCs and is not shared by other activated B cells. These findings establish radioresistance as a novel property of very early PCs and challenge the popular view that TI-1 antigens are unable to elicit the formation of long-lived PCs.
The hypoxic microenvironment modulates monocytic and dendritic cell inflammatory gene expression (133.10)
Authors: Varesio Luigi , Bosco Maria Carla , Blengio Fabiola , Pierobon Daniele , Raggi Federica , Fardin Paolo , Giovarelli Mirella 
Published: January 2023

Abstract
Hypoxia is a condition of low oxygen tension occurring in inflammatory lesions which creates a special microenvironment conditioning cell physiology. We investigated the molecular bases underlying the immunoregulatory functions of monocytes (Mn) and of terminally differentiated dendritic cells (mDCs) within the hypoxic microenvironment both in vitro and in vivo. Mn and mDCs hypoxic transcriptome was assessed using high-density oligonucleotide microarrays. The molecular pathways underlying gene transcription regulation by hypoxia were evaluated by promoter-driven reporter studies and EMSA. Profound modulation of the gene expression pattern was detected following Mn and DC exposure to 1% O2. We identified a significant cluster of hypoxia-responsive genes with immunological relevance, among which the macrophage inflammatory protein-3α (MIP-3α/CCL20) and the cytokine/extracellular matrix protein, osteopontin (OPN). Hypoxic upregulation of both genes was confirmed in vitro in primary Mn, Mn-derived macrophages, and DCs and in vivo in Mn cell recruited to the synovial joints of patients affected by Juvenile Idiopatic Arthritis (JIA), and associated with hypoxia-inducible factor-1α (HIF-1α) expression and NF-kB transcriptional activation. These studies lead to new perspectives on the impact of hypoxia on mononuclear phagocyte functions and to the definition of the mechanisms linking low pO2 to the pathogenesis of chronic inflammation.
AV411 (Ibudilast) and AV1013 are non-competitive inhibitors of macrophage migration inhibitory factor: a novel induced-fit allosteric inhibition mechanism (133.11)
Authors: Cho Yoonsang , Crichlow Gregg , Vermeire Jon , Leng Lin , Du Xin , Hodsdon Michael , Bucala Richard , Cappello Michael , Gross Matt , Gaeta Federico , Johnson Kirk , Lolis Elias 
Published: January 2023

Abstract
AV411 (Ibudilast) is an anti-inflammatory drug that was initially developed for the treatment of bronchial asthma but which also has been used for cerebrovascular and ocular indications. It is a non-selective inhibitor of various phosphodiesterases (PDEs) and has varied anti-inflammatory activity. More recently, AV411 has been studied as a possible therapeutic for the treatment of neuropathic pain and opioid withdrawal through its actions on glial cells. As described herein, the PDE inhibitors rolipram, theophylline, isobutylmethylxanthine (IBMX), cilostazol, arofylline, AV411 and its PDE-inhibition compromised analog AV1013 inhibit the catalytic and chemotactic functions of the pro-inflammatory protein, macrophage migration inhibitory factor (MIF). Enzymatic analysis indicates that these compounds are non-competitive inhibitors of the p-hydroxyphenylpyruvate (HPP) tautomerase activity of MIF. The allosteric binding site of AV411 and AV1013 is identified by NMR and X-ray crystallography, and the structural basis of inhibition is reported using the crystal structure of the MIF/AV1013/HPP ternary complex.
IFN-γ inhibits and TGF-β promotes thyrocyte hyperplasia and proliferation (TEC H/P) by modulating pro- and anti-proliferative molecules (134.11)
Authors: Fang Yujiang , Braley-Mullen Helen 
Published: January 2023

Abstract
Our previous in vivo studies showed that IFN-γ-/-NOD.H-2h4 mice develop severe TEC H/P. Proliferating TEC produce TGF-β and IFN-γ inhibits TEC H/P. This study was undertaken to directly test the hypothesis that IFN-γ inhibits and TGF-β promotes TEC H/P in vitro and explore the underlying mechanisms. Varying concentrations of IFN-γ and TGF-β were incubated with cultured TEC for 3 days. Cell proliferation was evaluated by IHC staining for PCNA, while apoptosis was determined by TUNEL staining. RT-PCR was used to evaluate the effect of cytokines on pro- and anti-proliferative molecules. The results indicate that IFN-γ inhibits and TGF-β promotes TEC proliferation in a dose dependent manner, and both cytokines had little effect on apoptosis. The anti-proliferative effect of IFN-γ correlates with upregulation of the anti-proliferative molecule P21 and downregulation of pro-proliferative molecules cyclin D and PCNA. Studies to determine the mechanisms by which TGF-β promotes TEC H/P are in progress. These in vitro results are consistent with our previous in vivo studies and provide direct support for the hypothesis that IFN-γ inhibits, while TGF-β promotes, TEC H/P. This extends our previous study by providing evidence that cytokines regulate TEC H/P by modulating pro- and anti-proliferative molecules. Such studies may increase our understanding of mechanisms underlying development of epithelial cell hyperplasia in the thyroid as well as other tissues and organs (NIH RO1 AI074857).
Systemic IL-12 administration modulates dendritic cells to overcome the immunosuppressive microenvironment of the liver (134.14)
Authors: Chan Tim , Back Timothy , Subleski Jeffrey , Weiss Jonathan , Ortaldo John , Wiltrout Robert 
Published: January 2023

Abstract
The liver is an immunologically unique organ containing tolerogenic dendritic cells (DCs) maintaining an immunosuppressive microenvironment. Immunotherapeutic strategies, such as systemic IL-12 therapy activate NK and T cells improving host outcome to tumor. However, the feedback effect of IL-12-based treatments on splenic and hepatic DCs in their microenvironments and their contributing roles to an anti-tumor response has not been examined. In this study, we demonstrate systemic IL-12 therapy results in a marked 2-3 fold increase in total splenic and hepatic DC populations in naïve and RENCA-bearing mice with all DC subsets increasing except for hepatic plasmacytoid DCs (pDCs). Increased costimulatory molecule expression in splenic and hepatic DCs was observed following IL-12 treatment but absent in common gamma chain knockout mice deficient in NK cells. Furthermore, hepatic DCs from IL-12 treated mice produced higher levels of IL-12 and TNFα when combined with TLR agonists and on a per cell basis, demonstrated significantly greater T cell proliferative capacity to levels similar to splenic DCs. Furthermore, IL-12 administration preferentially increased hepatic T cell activation and IFNγ expression compared to splenic T cells. Collectively, the data shows IL-12 administration enables DCs to overcome inherent suppressive components of the hepatic environment and potentially impact the design of IL-12-based immunotherapeutic strategies targeting hepatic malignancies.
Supraphysiological levels of IL-15 accelerate immune reconstitution in lymphopenic mice (134.16)
Authors: Bergamaschi Cristina , Ganneru Brunda , Rosati Margherita , Usami Osamu , Valentin Antonio , Beach Rachel , Alicea Candido , Felber Barbara , Pavlakis George 
Published: January 2023

Abstract
Loss of lymphocytes and T cells are a significant medical problem in AIDS and other immunodeficiencies, as well as after various treatments and cytoreductive therapies. T cell recovery after lymphopenia is delayed and incomplete and this can lead to prolonged immune dysfunctions. Lymphoablated patients have rapid and transient increases of circulating homeostatic cytokines IL-7 and IL-15, suggesting a role for these factors in immune reconstitution. Analysis of sera from lymphoablated patients revealed that the main form of circulating IL-15 is in a complex with soluble IL-15Rα (IL-15sRα). We have shown that injection of DNA expressing supraphysiological levels of IL-15/IL-15sRα in normal mice led to dose-dependent increases in the number and frequency of NK and T cells. The effect of IL-15/IL-15sRα on immune reconstitution was tested in mice lymphodepleted by cyclophosphamide (CTX) treatment. A single administration of IL-15/IL-15sRα DNA accelerates the full recovery of NK cells in spleen and lung. Two administrations of IL-15/IL-15sRα DNA promote the recovery of T cells in spleen within 14 days, faster than CTX-treated mice (p=0.017 Wilcoxon). T and NK cells from mice treated with supraphysiological levels of IL-15/IL-15sRα show greater degranulation and IFN-γ production after in vitro stimulation. These results suggest that IL-15 can contribute to rapid immune reconstitution, and suggest the use of IL-15/IL-15sRα to accelerate recovery from lymphopenia.
Regulation of TLR4 signaling in macrophages by Macrophage Stimulating Protein, the ligand for the Ron receptor tyrosine kinase (134.20)
Authors: Yu Shan , Ray Manujendra , Sharda Daniel , Wilson Caleph , Liu Qingpin , Kaushal Naveen , Prabhu K. Sandeep , Hankey Pamela 
Published: January 2023

Abstract
The Ron receptor tyrosine kinase regulates the balance between classical (M1) and alternative (M2) macrophage activation. The ligand for Ron, macrophage stimulating protein (MSP), inhibits the expression of iNOS, while promoting the expression of arginase I in primary murine macrophages. Ron-/- mice express elevated levels of IL-12 following endotoxin administration, resulting in increased serum IFNγ levels and enhanced susceptibility to septic shock. Here, we demonstrate that MSP inhibits LPS-induced IL-12p40 expression in primary macrophages. MSP does not inhibit the MyD88-independent activation of IRF3 and production of IFNβ in response to LPS, but limits the IFNβ-dependent phosphorylation of Stat1 following LPS stimulation. While MSP does not inhibit LPS-induced Tak1 phosphorylation or Map kinase activation in primary macrophages, the induction of IκB kinase (IKK) activity, IκB degradation and DNA binding of NFκB following LPS stimulation are delayed in the presence of MSP. In addition, Ron inhibits serine phosphorylation of p65 and NFκB transcriptional activity induced by LPS stimulation of TLR4. Finally, MSP inhibits the NFκB-dependent upregulation of the nuclear IκB family member, IκBζ, while inducing expression of the Stat3-regulated nuclear IκB family member, Bcl-3. LPS also induces expression of Ron and Sf-Ron in primary macrophages, suggesting that the upregulation of Ron by LPS could play a role in limiting subsequent LPS responses in macrophages.
The region in the common gamma chain between amino acids (aa) 314-323 dictates efficient activation of the insulin receptor substrate (IRS)-2 pathway by interleukin (IL)-4. (134.4)
Authors: Heller Nicola , Qi Xiulan , Gesbert Franck , Keegan Achsah 
Published: January 2023

Abstract
Previously, we demonstrated that the γC subunit of type I IL-4 receptor was required for robust tyrosine phosphorylation of the downstream adapter protein, IRS-2, and the robust expression of mRNA and protein of a subset of genes characteristic of alternatively-activated macrophages. The type II IL-4 receptor did not have this robust activity. In addition to the unique ability to bind Jak3, the cytoplasmic domain of human γC contains a putative IRS-2 docking motif and other γC-utilizing cytokines also activate IRS-2. Thus, we hypothesized that the γC cytoplasmic domain provides a docking site for IRS-2 cooperating with the site in IL-4Rα. To test this, full-length (FL) and γC truncation mutants were stably co-expressed with wildtype (WT) IL-4Rα in CHO cells; signaling responses to IL-4 were examined. IL-4-induced IRS-2 and STAT6 phosphorylation was observed in CHO expressing FL γC and γC truncated at aa323 but not in cells expressing γC truncated at aa308 or 285. These data suggest robust activation of IRS-2 and STAT6 by IL-4 requires a 15 aa portion of γC between aa314-323. This interval did not contain Tyr325, part of the putative IRS-2 docking motif. Previous studies in other receptor systems suggested that aa323-335 was required for Jak3 engagement. The requirement for IL-4-induced JAK3 recruitment/activation will be examined in these CHO transfectants. Supported by HL096897 (NMH) and AI038985 (ADK).
Mechanistic study of leptin-enhanced B cell survival (134.7)
Authors: Lam Queenie , Lu Liwei 
Published: January 2023

Abstract
Regulation of apoptosis and cell cycle progression plays an essential role in the maintenance of B cell homeostasis because the fine balance of survival and death of B cells is critical to prevent occurrence of lymphocytic disorders. During the past decade, remarkable progress in understanding the process of B development has been achieved but much less is known on the survival niches that are critical to the maintenance of B cell homeostasis. Leptin has recently been recognized to play a crucial role in modulating the immune response but it has remained unclear whether and how leptin signaling is involved in modulating B cell physiology. In our studies we demonstrate that leptin promotes B cell survival by inhibiting apoptosis and enhancing cell cycle progression, which are associated with the induction of expression of Bcl-2 and Cyclin D1, respectively. We further show that leptin can induce the expressions of Bcl-2 and Cyclin D1 by two pathways; by activating their promoters directly and by suppressing miRNAs that target their putative 3’untranslated region to enhance their expressions indirectly. These findings provide insights into the important role of leptin in maintaining B cell homeostasis, which will lead to a fuller understanding of the regulation of adaptive immunity and be beneficial to the future design of alternative therapeutic strategies in B cell-derived disorders.
Vitamin D receptor deficiency alters the ability of CD8 T cells to induce inflammatory bowel disease. (135.14)
Authors: Bruce Danny , Cantorna Margherita 
Published: January 2023

Abstract
Vitamin D receptor (VDR) KO mice are more susceptible to several different experimental models of inflammatory bowel disease (IBD) including the Rag KO transfer model when naïve VDR KO CD4 T cells are used to induce disease. CD8 T cells from WT mice do not induce IBD when transferred to Rag KO mice. Conversely, VDR KO CD8 T cells induce IBD in Rag KO recipients. There is no difference in the expression of CD62L, CD44, CCR9 and α4β7 or secretion of IFN-γ and TNF-α between WT and VDR KO CD8 T cells. Disease induced by VDR KO CD8 T cells is mild and the recipients do not lose weight or show outward signs of disease. Instead histological evidence of inflammation and increased numbers of CD8 T cells in the IEL characterize the disease. While WT CD8 T cells fail to induce IBD when transferred to Rag KO mice, they do induce a fulminating form of IBD when transferred to Rag/VDR double KO (DKO) mice. Therefore, the host expression of the VDR alters CD8 T cell development and or function. Experiments to probe the cause of CD8 T cell induced pathology in DKO mice are underway.
GM-CSF control of macrophage differentiation is a critical effector of Th17 responses in vivo (135.27)
Authors: Barin Jobert , Baldeviano G. , Talor Monica , Zheng Dongfeng , Čiháková Daniela , Rose Noel 
Published: January 2023

Abstract
Like many other tissue-directed models of autoimmune disease, experimental autoimmune myocarditis (EAM) is mediated by Th17-directed pathology. The composition of cardiac infiltrates in EAM is predominantly monocytic, indicating that these cells are most likely to be inflammatory effectors in this disease process. Like other Th17 autoimmune diseases, IFNγ-deficient mice develop very severe disease. We observed enhanced GM-CSF production from autoantigen-specific IFNγ-/- CD4+ cells, from the heart and spleen, suggesting that the induction of GM-CSF by Th17 cells may participate in disease pathophysiology. After generating IFNγ-/-IL17A-/- double-knockout mice, we observed that the production of GM-CSF in CD4+ is driven by IL17 signaling. Towards this end, we generated bone marrow-derived macrophages (BMMϕ) in vitro, in the presence of GM-CSF, rather than M-CSF. Following transfer, recipients of GM-CSF BMMϕ developed more severe disease than controls. This severe disease was accompanied by enhanced fibrosis and progression to dilated cardiomyopathy. This report links GM-CSF control of macrophage differentiation to the functional consequences of Th17-mediated autoimmunity
Tissue tropism of autoreactive memory CD4 T-cells (135.30)
Authors: Lees Jason , Farber Donna 
Published: January 2023

Abstract
The continual presence of antigen in site-specific autoimmune diseases, such as type 1 diabetes, makes it difficult to determine the relative roles of effector and memory CD4 T-cells in perpetuation of established autoimmunity. It is not known to what extent memory cells retain effector and tissue trafficking capacities of the primary autoimmune response that established them and the timing and mechanisms involved in imprinting of these attributes is unclear. In this study, we hypothesized that pancreas homing diabetogenic effector cells may develop into memory T-cells with distinct trafficking capacities. We used a mouse model of type 1 diabetes in which transferred influenza hemagglutinin (HA)-specific CD4 T-cells induce pancreatic islet destruction in mice that express HA via an insulin promoter. We examined the functional and trafficking capacities of memory T-cells derived in the absence of further antigen recognition by adoptive transfer of tissue resident effector T-cell populations recovered from the spleen or pancreas throughout diabetes development into wild type mice. Effector cells recovered from both spleen and pancreas during diabetes onset generated memory T-cells, but only memory T-cells derived from the pancreas were capable of retrafficking to the pancreas in the absence of antigen. These data demonstrate that tissue effector CD4 T-cells contain a memory precursor imprinted with tissue trafficking specificity prior to development of memory T-cells.
Kinetics of Th17 development in type 1 diabetes (135.35)
Authors: Li Cheng-Rui (Michael) , Bradley Linda 
Published: January 2023

Abstract
Type 1 diabetes (T1D) is an autoimmune disease. It has been established that Th1 cells play a central role in the autoimmune attack against islet β cells. The Th17 subset has recently been implicated in many autoimmune disease models. However, its role in T1D is still unclear. In diabetic NOD mice, we found elevated serum IL-17 levels and IL-17 producing infiltrating CD4+ T cells from islets. Adoptive transfer of in vitro differentiated islet-antigen-specific Th17 cells induced diabetes in recipient NOD.Scid mice with similar kinetics of that induced by Th1 cells. These data suggest a possible causal role of Th17 cell in T1D. To study the development of Th17 cells in vivo, we transferred naïve CD4+ T cells into neonatal NOD mice, and monitored phenotype and function of both transferred and endogenous T cells for up to 35 weeks. Surprisingly, we were able to identify islet infiltrating endogenous CD4+ T cells that expressed either IFNγ or IL-17 in 2-week-old NOD mice. Transferred naïve cells proliferated in recipients; they rapidly acquired effector memory phenotype and effector cytokine production. As expected, the frequency of IFNγ-producing CD4+ T cells increased over time in both endogenous and transferred populations. In contrast, the frequency of IL17-producing CD4+ T cells did not significantly change over time. These data suggest that, in T1D model, the Th17 cells may be a dynamic population with constant turnover rate, while contributing to diabetes pathogenesis.