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CD4 +  T cells, specifically Th cells (Th1 and Th17) and regulatory T cells (Tregs), play a pivotal role in the pathogenesis of multiple sclerosis (MS), a demyelinating autoimmune disease of the CNS. STAT3 inhibitors are potential therapeutic targets for several immune disorders. In this study, we investigated the role of a well-known STAT3 inhibitor, S3I-201, in experimental autoimmune encephalomyelitis (EAE), a model of MS. Following induction of EAE, mice were intraperitoneally administered S3I-201 (10 mg/kg) each day, beginning on day 14 and continuing till day 35 and were evaluated for clinical signs. Flow cytometry was used to investigate further the effect of S3I-201 on Th1 (IFN-γ, STAT1, pSTAT1, and T-bet), Th17 (IL-17A, STAT3, pSTAT3, and RORγt), and regulatory T cells (Treg, IL-10, TGF-β1, and FoxP3) expressed in splenic CD4 + T cells. Moreover, we analyzed the effects of S3I-201 on mRNA and protein expression of IFN-γ, T-bet, IL-17A, STAT1, STAT3, pSTAT1, pSTAT3, RORγ, IL-10, TGF-β1, and FoxP3 in the brains of EAE mice. The severity of clinical scores decreased in S3I-201-treated EAE mice compared to vehicle-treated EAE mice. S3I-201 treatment significantly decreased CD4 + IFN-γ + , CD4 + STAT1 + , CD4 + pSTAT1 + , CD4 + T-bet + , CD4 + IL-17A + , CD4 + STAT3 + , CD4 + pSTAT3 + , and CD4 + RORγt + and increased CD4 + IL-10 + , CD4 + TGF-β1 + , and CD4 + FoxP3 + in the spleens of EAE mice. Additionally, S3I-201 administration in EAE mice significantly decreased the mRNA and protein expression of Th1 and Th17 and increased those of Treg. These results suggest that S3I-201 may have novel therapeutic potential against MS., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The authors declare no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Psoriasis is a complex, chronic relapsing and inflammatory skin disorder with a prevalence of approximately 2% in the general population worldwide. Psoriasis can be triggered by infections, physical injury and certain drugs. The most common type of psoriasis is psoriasis vulgaris, which primarily features dry, well-demarcated, raised red lesions with adherent silvery scales on the skin and joints. Over the past few decades, scientific research has helped us reveal that innate and adaptive immune cells contribute to the chronic inflammatory pathological process of psoriasis. In particular, dysfunctional helper T cells (Th1, Th17, Th22, and Treg cells) are indispensable factors in psoriasis development. When stimulated by certain triggers, antigen-presenting cells (APCs) can release pro-inflammatory factors (IL-23, IFN-α and IL-12), which further activate naive T cells and polarize them into distinct helper T cell subsets that produce numerous cytokines, such as TNF, IFN-γ, IL-17 and IL-22, which act on keratinocytes to amplify psoriatic inflammation. In this review, we describe the function of helper T cells in psoriasis and summarize currently targeted anti-psoriatic therapies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Hu, Wang, Gao, Zheng, Li, Mu and Tong.)

Oligoarticular juvenile idiopathic arthritis (oligo JIA) is the most common form of chronic inflammatory arthritis in children, yet the cause of this disease remains unknown. To understand immune responses in oligo JIA, we immunophenotyped synovial fluid T cells with flow cytometry, bulk RNA-Seq, single-cell RNA-Seq (scRNA-Seq), DNA methylation studies, and Treg suppression assays. In synovial fluid, CD4+, CD8+, and γδ T cells expressed Th1-related markers, whereas Th17 cells were not enriched. Th1 skewing was prominent in CD4+ T cells, including Tregs, and was associated with severe disease. Transcriptomic studies confirmed a Th1 signature in CD4+ T cells from synovial fluid. The regulatory gene expression signature was preserved in Tregs, even those exhibiting Th1 polarization. These Th1-like Tregs maintained Treg-specific methylation patterns and suppressive function, supporting the stability of this Treg population in the joint. Although synovial fluid CD4+ T cells displayed an overall Th1 phenotype, scRNA-Seq uncovered heterogeneous effector and regulatory subpopulations, including IFN-induced Tregs, peripheral helper T cells, and cytotoxic CD4+ T cells. In conclusion, oligo JIA is characterized by Th1 polarization that encompasses Tregs but does not compromise their regulatory identity. Targeting Th1-driven inflammation and augmenting Treg function may represent important therapeutic approaches in oligo JIA.

Gene expression programs controlled by lineage-determining transcription factors are often conserved between species. However, infectious diseases have exerted profound evolutionary pressure, and therefore the genes regulated by immune-specific transcription factors might be expected to exhibit greater divergence. T-bet (Tbx21) is the immune-specific, lineage-specifying transcription factor for T helper type I (Th1) immunity, which is fundamental for the immune response to intracellular pathogens but also underlies inflammatory diseases. We compared T-bet genomic targets between mouse and human CD4 + T cells and correlated T-bet binding patterns with species-specific gene expression. Remarkably, we found that the majority of T-bet target genes are conserved between mouse and human, either via preservation of binding sites or via alternative binding sites associated with transposon-linked insertion. Species-specific T-bet binding was associated with differences in transcription factor-binding motifs and species-specific expression of associated genes. These results provide a genome-wide cross-species comparison of Th1 gene regulation that will enable more accurate translation of genetic targets and therapeutics from pre-clinical models of inflammatory and infectious diseases and cancer into human clinical trials., (© 2021 Henderson et al.)

Transcriptional analysis of complex biological scenarios has been used extensively, even though sometimes the results of such analysis may prove imprecise or difficult to interpret due to an overwhelming amount of information. In this study, a large-scale real-time qPCR experiment was coupled to multivariate statistical analysis in order to describe the main immunological events underlying the early L. infantum infection in livers of BALB/c mice. High-throughput qPCR was used to evaluate the expression of 223 genes related to immunological response and metabolism 1, 3, 5, and 10 days post infection. This integrative analysis showed strikingly different gene signatures at 1 and 10 days post infection, revealing the progression of infection in the experimental model based on the upregulation of particular immunological response patterns and mediators. The gene signature 1 day post infection was not only characterized by the upregulation of mediators involved in interferon signaling and cell chemotaxis, but also the upregulation of some inhibitory markers. In contrast, at 10 days post infection, the upregulation of many inflammatory and Th1 markers characterized a more defined gene signature with the upregulation of mediators in the IL-12 signaling pathway. Our results reveal a significant connection between the expression of innate immune response and metabolic and inhibitory markers in early L. infantum infection of the liver.

Purpose: Systemic lupus erythematosus (SLE) is a serious autoimmune disease. Its molecular pathogenesis, especially the long non-coding RNA (lncRNA) function, remains unclear. We want to investigate the lncRNA dysregulation profile and their molecular mechanisms in SLE., Methods: In this study, we analyzed the transcriptome profiles (RNA-seq) of peripheral blood mononuclear cells (PBMCs) from SLE patients and two published transcriptome datasets to explore lncRNA profiles. The differentially expressed lncRNAs were confirmed by quantitative real-time PCR in another set of female patients. We constructed the lncRNA-mRNA regulatory networks by performing weighted gene co-expression network analysis (WGCNA). Dysregulated lncRNA AC007278.2 was repressed by short hairpin RNA (shRNA) in Jurkat cells. Dual-luciferase reporter gene assay was performed to investigate the regulatory mechanism of AC007278.2 on target gene CCR7., Results: We observed dominant up-regulation of transcripts, including mRNAs and lncRNAs, in SLE patients. By WGCNA method, we identified three modules that were highly related to SLE. We then focused on one lncRNA, AC007278.2 , with a T-helper 1 lineage-specific expression pattern. We observed consistently higher AC007278.2 expression in SLE patients. Co-expression network revealed that AC007278.2 participated in the innate immune response and inflammatory bowel disease pathways. By knocking down AC007278.2 expression, we found that AC007278.2 could regulate the expression of inflammatory and cytokine stimulus response-related genes, including CCR7 , AZU1 , and TNIP3 . AC007278.2 inhibits the functional CCR7 promoter to repress its transcription, thereby regulating autoimmunity and follicular T-helper cell differentiation., Conclusion: In summary, our study indicated the important regulatory role of lncRNAs in SLE. AC007278.2 may be treated as a novel biomarker for SLE diagnosis and treatment., Competing Interests: Authors JM and DC were employed by the company ABLife Inc. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 You, Zhao, Wu, Mao, Ge, Guo, Zhao, Chen and Song.)

The importance of cellular metabolic adaptation in inducing robust T cell responses is well established. However, the mechanism by which T cells link information regarding nutrient supply to clonal expansion and effector function is still enigmatic. Herein, we report that the metabolic sensor adenosine monophosphate-activated protein kinase (AMPK) is a critical link between cellular energy demand and translational activity and, thus, orchestrates optimal expansion of T cells in vivo. AMPK deficiency did not affect T cell fate decision, activation, or T effector cell generation; however, the magnitude of T cell responses in murine in vivo models of T cell activation was markedly reduced. This impairment was global, as all T helper cell subsets were similarly sensitive to loss of AMPK which resulted in reduced T cell accumulation in peripheral organs and reduced disease severity in pathophysiologically as diverse models as T cell transfer colitis and allergic airway inflammation. T cell receptor repertoire analysis confirmed similar clonotype frequencies in different lymphoid organs, thereby supporting the concept of a quantitative impairment in clonal expansion rather than a skewed qualitative immune response. In line with these findings, in-depth metabolic analysis revealed a decrease in T cell oxidative metabolism, and gene set enrichment analysis indicated a major reduction in ribosomal biogenesis and mRNA translation in AMPK-deficient T cells. We, thus, provide evidence that through its interference with these delicate processes, AMPK orchestrates the quantitative, but not the qualitative, manifestation of primary T cell responses in vivo., (© 2020 Federation of American Societies for Experimental Biology.)

The tick Rhipicephalus microplus is a harmful parasite of cattle that causes considerable economic losses to the cattle breeding industry. Although R. microplus saliva (Rm-saliva) contains several immunosuppressants, any association between Rm-saliva and the expression of immunoinhibitory molecules, such as programmed death (PD)-1 and PD-ligand 1 (PD-L1), has not been described. In this study, flow cytometric analyses revealed that Rm-saliva upregulated PD-1 expression in T cells and PD-L1 expression in CD14 + and CD11c + cells in cattle. Additionally, Rm-saliva decreased CD69 expression in T cells and Th1 cytokine production from peripheral blood mononuclear cells. Furthermore, PD-L1 blockade increased IFN-γ production in the presence of Rm-saliva, suggesting that Rm-saliva suppresses Th1 responses via the PD-1/PD-L1 pathway. To reveal the upregulation mechanism of PD-1/PD-L1 by Rm-saliva, we analyzed the function of prostaglandin E 2 (PGE 2 ), which is known as an inducer of PD-L1 expression, in Rm-saliva. We found that Rm-saliva contained a high concentration of PGE 2 , and PGE 2 treatment induced PD-L1 expression in CD14 + cells in vitro. Immunohistochemical analyses revealed that PGE 2 and PD-L1 expression was upregulated in tick-attached skin in cattle. These data suggest that PGE 2 in Rm-saliva has the potential to induce the expression of immunoinhibitory molecules in host immune cells.

Dengue virus (DENV), an arbovirus, strongly activates mast cells (MCs), which are key immune cells for pathogen immune surveillance. In animal models, MCs promote clearance of local peripheral DENV infections but, conversely, also promote pathological vascular leakage when widely activated during systemic DENV infection. Since DENV is a human pathogen, we sought to ascertain whether a similar phenomenon could occur in humans by characterizing the products released by human MCs (huMCs) upon direct (antibody-independent) DENV exposure, using the phenotypically mature huMC line, ROSA. DENV did not productively infect huMCs but prompted huMC release of proteases and eicosanoids and induced a Th1-polarized transcriptional profile. In co-culture and trans-well systems, huMC products activated human microvascular endothelial cells, involving transcription of vasoactive mediators and increased monolayer permeability. This permeability was blocked by MC-stabilizing drugs, or limited by drugs targeting certain MC products. Thus, MC stabilizers are a viable strategy to limit MC-promoted vascular leakage during DENV infection in humans.

Natural secondary metabolites of sponges of the genus Haliclona are associated with an array of biological activity with therapeutic usage. We investigated the immunopharmacological properties of a presumably novel marine sponge species from Sri Lanka, Haliclona ( Soestella ) sp. Sponge material was collected from southern Sri Lanka by scuba diving. Sponge identification was based on spicule and skeleton morphology using light microscopy. Selected in vivo and ex vivo tests investigated nonfunctional and functional immunomodulatory activity of the Haliclona ( Soestella ) sp. crude extract (HSCE) in the Wistar rat model. Compared to the controls, rats orally gavaged daily for 14 consecutive days with 15 mg/kg dose of the HSCE manifested a significant reduction of immune cell counts of total WBCs (by 17%; p < 0.01), lymphocytes (38%), platelets (52%), splenocytes (20%), and bone marrow cells (BMC; 60%) ( p < 0.001), with a concurrent increase in the neutrophil : lymphocyte ratio ( p < 0.05); RBC counts abated by 53% ( p < 0.001). A significant reduction of the splenosomatic index was evident with the 10 and 15 mg/kg doses ( p < 0.001). Rat plasma TNF- α cytokine level was augmented by tenfold ( p < 0.001), IL-6 level by twofold ( p < 0.01) with the 15 mg/kg HSCE treatment, while IL-10 was detectable in rat plasma only with this treatment; the corresponding Th 1  : Th 2 cytokine ratio (TNF- α  : IL-10) was indicative of an unequivocal Th1-skewed cytokine response ( p < 0.01). Ex vivo bone marrow cell and splenocyte proliferation were significantly and dose dependently impaired by HSCE (IC 50 0.719 and 0.931  μ g/mL, respectively; p < 0.05). Subacute toxicity testing established that HSCE was devoid of general toxic, hepatotoxic, and nephrotoxic effects. In conclusion, HSCE was orally active, nontoxic, and effectively suppressed nonfunctional and functional immunological parameters of Wistar rats, suggestive of the potential use of the HSCE as an immunosuppressant drug lead., Competing Interests: The authors do not have any conflicts of interest regarding this document., (Copyright © 2020 Varuni Gunathilake et al.)

Dendritic cells (DCs) and T cells play important roles in immune regulation, and modulating their function is an approach for developing preventive or therapeutic strategies against immune disorders. Herein, the effect of pterostilbene (PSB) (3',5'-dimethoxy-resveratrol)-a resveratrol-related polyphenol found in blueberries-on immune regulation was evaluated. Using an in vitro co-culture system, PSB was found to exert the strongest inhibitory effect among all tested resveratrol derivatives on DC-mediated T cell proliferation; moreover, PSB treatment decreased the Th1 and Th17 populations and increased the regulatory T cell (Treg) population. Upon co-stimulation with anti-CD3 and anti-CD28 antibodies, PSB inhibited CD4 + T cell proliferation and differentiation into Th1 cells. Additionally, PSB acted on DCs to suppress the lipopolysaccharide-induced transactivation of genes encoding antigen presentation-related molecules and inflammatory cytokines by attenuating the DNA-binding ability of the transcription factor PU.1. Furthermore, PSB promoted DC-mediated Foxp3 + Treg differentiation, and PU.1 knockdown increased DC-induced Treg activity. Oral administration of PSB alleviated the symptoms of dextran sulfate sodium-induced colitis and decreased tumor necrosis factor-α expression in mice. Thus, PSB treatment ameliorates colonic inflammation., (© 2020 The Authors. The FASEB Journal published by Wiley Periodicals LLC on behalf of Federation of American Societies for Experimental Biology.)

Recent genome-wide association studies have identified over 230 genetic risk loci for multiple sclerosis. Current experimental autoimmune encephalomyelitis (EAE) models requiring active induction of disease may not be optimally suited for the characterization of the function of these genes. We have thus used gene expression profiling to study whether spontaneous opticospinal EAE (OSE) or MOG-induced EAE mirrors the genetic contribution to the pathogenesis of multiple sclerosis more faithfully. To this end, we compared gene expression in OSE and MOG EAE models and analyzed the relationship of both models to human multiple sclerosis risk genes and T helper cell biology. We observed stronger gene expression changes and an involvement of more pathways of the adaptive immune system in OSE than MOG EAE. Furthermore, we demonstrated a more extensive enrichment of human MS risk genes among transcripts differentially expressed in OSE than was the case for MOG EAE. Transcripts differentially expressed only in diseased OSE mice but not in MOG EAE were significantly enriched for T helper cell-specific transcripts. These transcripts are part of immune-regulatory pathways. The activation of the adaptive immune system and the enrichment of both human multiple sclerosis risk genes and T helper cell-specific transcripts were also observed in OSE mice showing only mild disease signs. These expression changes may, therefore, be indicative of processes at disease onset. In summary, more human multiple sclerosis risk genes were differentially expressed in OSE than was observed for MOG EAE, especially in T H 1 cells. When studying the functional role of multiple sclerosis risk genes and pathways during disease onset and their interactions with the environment, spontaneous OSE may thus show advantages over MOG-induced EAE., (Copyright © 2020 Faber, Kurtoic, Krishnamoorthy, Weber, Pütz, Müller-Myhsok, Weber and Andlauer.)

Purpose of the study : Multiple sclerosis is a CD4 + T cell mediated autoimmune disease characterized by inflammatory demyelination in the central nervous system. Acetylcholine (ACh) has been reported to be released by T lymphocytes and plays as an inflammation and immune regulator through the participation of T cells. However, both attenuated and aggravated effects of ACh in inflammation were found. The aim of this study is to further investigate the role of ACh in experimental autoimmune encephalomyelitis (EAE). Materials and methods: The left cervical vagotomy was performed to inhibit ACh release with the sham-operation as control. ACh in cerebral cortex and splenocytes culture supernatants of EAE mice were determined. Interleukin-6, interferon-γ, interleukin-4 and interleukin-17A in brain and splenocytes culture supernatants were evaluated by enzyme-linked immunosorbent assay. The proportion of CD4 + T cells and subsets were assessed by flow cytometry. Results: Compared with the sham-operation group, improved clinical and pathological parameters as well as decreased interleukin-6, interferon-γ, interleukin-4 and interleukin-17A were found in EAE mice with vagotomy suppressing the ACh. Marked reductions of CD4 + and CD4 + ChAT + cells, as well as significant decrease in Th1 with a bias to Th2 in Th1/Th2 balance and increased ChAT + Th2 proportion in the spleen were also observed in vagotomized mice. Conclusions: These findings emphasize that inhibiting ACh release by vagotomy can ameliorate the exacerbation of EAE through suppressing CD4 + T cells proliferation and regulating the differentiation of Th1, Th2 and Th17.

Dendritic cells (DCs) are key linkages between innate immunity and acquired immunity. The antigens that promote the functions of DCs might be the effective candidates of novel vaccine. In this research, the ability of ubiquitin-conjugating enzyme (UCE), a recognized common antigens among chicken Eimeria species, to stimulate DCs of chickens were evaluated. We cloned UCE gene from Eimeria maxima (EmUCE), and its protein expression was confirmed by SDS-PAGE and western-blot. Immunofluorescence assay confirmed the binding of rEmUCE on the surface of chicken splenic-derived DCs (ChSP-DCs). Flow cytometric analysis showed that rEmUCE-treated ChSP-DCs increased MHCII, CD1.1, CD11c, CD80, and CD86 phenotypes. qRT-PCR indicated that transcript levels of maturation markers CCL5, CCR7, and CD83 in ChSP-DCs were upregulated in response to rEmUCE. Following rEmUCE treatment, chSP-DCs activated TLR signaling and inhibited Wnt signaling. Moreover, rEmUCE promoted DC-mediated T-cell proliferation in DC/T-cell co-incubation. Interestingly, CD3 + /CD4 + T-cells were significantly enhanced when rEmUCE-treated chSP-DCs were co-incubated with T-cells. Cytokine secretion pattern of rEmUCE-stimulated ChSP-DCs revealed that the production of IL-12 and IFN-γ was increased whereas IL-10 and TGF-β were unchanged. Likewise, the co-incubation of ChSP-DCs with T-cells indicated increased production of IFN-γ but not IL-4. Collectively, rEmUCE could polarize DCs to immunogenic phenotype and shift the immune cells towards Th1 response. Our observations provide valuable insight for future research aimed at vaccine development against avian coccidiosis., Competing Interests: Declaration of competing interest The authors declare that they have no conflict with competing interests., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

CD4 + T follicular helper (T FH ) cells provide help to B cells and promote antibody-mediated immune responses. Increasing evidence supports the existence of T FH populations that secrete cytokines typically associated with the effector functions of other CD4 + T cell subsets. These include T helper 1 (T H 1)-biased T FH (T FH1 ) cells that have recognized roles in both immune responses to pathogens and also the pathogenesis of autoimmune disease. Given their apparent importance to human health, there is interest in understanding the mechanisms that regulate T FH1 cell formation and function. However, their origin and the molecular requirements for their differentiation are unclear. Here, we describe a population of murine T H 1-derived, T FH1 -like cells that express the chemokine receptor Cxcr3 and produce both the T H 1 cytokine interferon-γ and the T FH -associated cytokine interleukin-21 (IL-21). Furthermore, these T FH1 -like cells promote B cell activation and antibody production at levels indistinguishable from conventional IL-6-derived T FH -like cells. Regarding their regulatory requirements, we find that IL-12 signaling is necessary for the differentiation and function of this T FH1 -like cell population. Specifically, IL-12-dependent activation of STAT4, and unexpectedly STAT3, promotes increased expression of IL-21 and the T FH lineage-defining transcription factor Bcl-6 in T FH1 -like cells. Taken together, these findings provide insight into the potential origin and differentiation requirements of T FH1 cells.

Th1 and Th17 are important in the pathogenesis of autoimmune diseases and they depend on glycolysis as a source of energy. T cell antigen receptor signaling phosphorylates a serine/threonine kinase, calcium/calmodulin-dependent protein kinase IV (CaMK4), and promotes glycolysis. Based on these findings we hypothesized that CaMK4 promotes glycolysis. Camk4-deficient CD4+ T cells and cells treated with a CaMK4 inhibitor had less glycolysis compared with their counterparts. Pull-down of CaMK4 and mass spectrometry identified pyruvate kinase muscle isozyme (PKM), the final rate-limiting enzyme in glycolysis, as a binding partner. Coimmunoprecipitation and Western blotting showed that CaMK4 interacts directly with PKM2. Camk4-deficient CD4+ T cells displayed decreased pyruvate kinase activity. Silencing or pharmacological inhibition of PKM2 reduced glycolysis and in vitro differentiation to Th1 and Th17 cells, while PKM2 overexpression restored Th17 cell differentiation. Treatment with a PKM2 inhibitor ameliorated experimental autoimmune encephalomyelitis and CD4+ T cells treated with PKM2 inhibitor or Pkm2-shRNA caused limited disease activity in an adoptive cell transfer model of experimental autoimmune encephalomyelitis. Our data demonstrate that CaMK4 binds to PKM2 and promotes its activity, which is requisite for Th1 and Th17 differentiation in vitro and in vivo. PKM2 represents a therapeutic target for T cell-dependent autoimmune diseases.

Multiple sclerosis is an autoimmune disease of the central nervous system (CNS) mediated by CD4 + T cells and modeled via experimental autoimmune encephalomyelitis (EAE). Inhibition of PRMT5, the major Type II arginine methyltransferase, suppresses pathogenic T cell responses and EAE. PRMT5 is transiently induced in proliferating memory inflammatory Th1 cells and during EAE. However, the mechanisms driving PRMT5 protein induction and repression as T cells expand and return to resting is currently unknown. Here, we used naive mouse and memory mouse and human Th1/Th2 cells as models to identify mechanisms controlling PRMT5 protein expression in initial and recall T cell activation. Initial activation of naive mouse T cells resulted in NF-κB-dependent transient Prmt5 transcription and NF-κB, mTOR and MYC-dependent PRMT5 protein induction. In murine memory Th cells, transcription and miRNA loss supported PRMT5 induction to a lesser extent than in naive T cells. In contrast, NF-κB/MYC/mTOR-dependent non-transcriptional PRMT5 induction played a major role. These results highlight the importance of the NF-κB/mTOR/MYC axis in PRMT5-driven pathogenic T cell expansion and may guide targeted therapeutic strategies for MS.

Thorough understanding of the complex pathophysiology of osteoarthritis (OA) is necessary in order to open new avenues for treatment. The aim of this study was to characterize the CD4 + T cell population and evaluate their activation and polarization status in OA joints. Fifty-five patients with end-stage knee OA (Kellgren-Lawrence grades III-IV) who underwent surgery for total knee arthroplasty (TKA) were enrolled into this study. Matched samples of synovial membrane (SM), synovial fluid (SF) and peripheral blood (PB) were analysed for CD3 + CD4 + CD8 - T cell subsets [T helper type 1 (Th1), Th2, Th17, regulatory T cells] and activation status (CD25, CD69, CD45RO, CD45RA, CD62L) by flow cytometry. Subset-specific cytokines were analysed by cytometric bead array (CBA). SM and SF samples showed a distinct infiltration pattern of CD4 + T cells. In comparison to PB, a higher amount of joint-derived T cells was polarized into CD3 + CD4 + CD8 - T cell subsets, with the most significant increase for proinflammatory Th1 cells in SF. CBA analysis revealed significantly increased immunomodulating cytokines [interferon (IFN)-γ, interleukin (IL)-2 and IL-10] in SF compared to PB. Whereas in PB only a small proportion of CD4 + T cells were activated, the majority of joint-derived CD4 + T cells can be characterized as activated effector memory cells (CD69 + CD45RO + CD62L - ). End-stage OA knees are characterized by an increased CD4 + T cell polarization towards activated Th1 cells and cytokine secretion compared to PB. This local inflammation may contribute to disease aggravation and eventually perpetuate the disease process., (© 2018 British Society for Immunology.)

The immunosuppressive tumor microenvironment (TME) established by tumor cells, stromal cells and inhibitory immune cells counteracts the function of tumor reactive T cells. Tumor associated macrophages (TAMs) showing functional plasticity contribute to this process as so called M2-like macrophages can suppress the function of effector T cells and promote their differentiation into regulatory T cells (Tregs). Furthermore, tumor antigen specific CD4 + T effector cells can essentially sustain anti-tumoral immune responses as shown for various tumor entities, thus suggesting that cognate interaction between tumor antigen-specific CD4 + Th1 cells and TAMs might shift the intra-tumoral M1/M2 ratio toward M1. This study demonstrates repolarization of M2-like PECs upon MHC II-restricted interaction with tumor specific CD4 + Th1 cells in vitro as shown by extensive gene and protein expression analyses. Moreover, adoptive transfer of OVA-specific OT-II cells into C57BL/6 mice bearing OVA expressing IA b-/- tumors resulted in increased accumulation of M1-like TAMs with enhanced M1 associated gene and protein expression profiles. Thus, this paper highlights a so far underestimated function of the CD4 + Th1/TAM axis in re-conditioning the immunosuppressive tumor microenvironment.

Regulatory T cells (Tregs) are critical for maintaining immune response and enhancing their differentiation has therapeutic implications for autoimmune diseases. In this study, we investigated the effects of thymol a well-known monoterpene from Thyme on differentiation and function of Tregs. In vitro generation of Tregs from purified naïve CD4 + CD25 - T cells in the presence of thymol was carried out. Suppressor activity of generated Tregs was examined by changes in the proliferation of CFSE-labeled conventional T cells. Thymol promotes differentiation of naïve CD4 + CD25 - T cells to CD4 + CD25 + Foxp3 + Tregs [66.9-71.8% vs. control (47%)] and increased intensity of Foxp3 expression on Tregs (p < 0.01). In functional assay, an increased immune suppression by thymol-induced Tregs (≈2.5 times of untreated Tregs) was detected. For in vivo study, thymol was intraperitoneally administered to ovalbumin (Ova)-immunized mice. Flow cytometry assessment of spleens from thymol-treated Ova-immunized mice showed increased number of CD4 + Foxp3 + Tregs (>8%, p < 0.01(and decreased levels of CD4 + T-bet + Th1 and CD4 + RORγt + Th17 cells resulted in significant decreased Th1/Treg and Th17/Treg ratios. In ex vivo Ova challenge of splenocytes from thymol-treated Ova-immunized mice, similarly higher levels of CD4 + Foxp3 + Tregs, and also elevated TGF-β expression in CD4 + Foxp3 + population (48.1% vs. 18.9% in untreated Ova-immunized group) and reduced IFN-γ-producing CD4 + T-bet + T cells and IL-17-producing CD4 + RORγt + T cells were detected. This led to marked decreased ratios of IFNγ/TGF-β and IL-17/TGF-β expressions. In conclusion, this study revealed thymol as a compound with enhancing effects on Treg differentiation and function, which may have potential benefits in treatment of immune-mediated diseases with Th1/Th17 over-activation., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Brucella canis is a small intracellular Gram-negative bacterium that frequently leads to chronic infections highly resistant to antibiotic therapy in dogs. Also, it causes mild human brucellosis compared to other zoonotic Brucella spp. Herein we characterize the cellular immune response elicited by B. canis by analysing human and canine CD4 + T cells after stimulation with autologous monocyte-derived dendritic cells (MoDCs). Human and canine B. canis-primed MoDCs stimulated autologous CD4 + T cells; however, a Th1 response was triggered by human MoDCs, whereas canine MoDCs induced Th1/Th17 responses, with increased CD4 + T cells producing IFN-γ and IL-17A simultaneously. Each pattern of cellular response may contribute to host susceptibility, helping to understand the differences in B. canis virulence between these two hosts. In addition, other aspects of canine immunology are unveiled by highlighting the participation of IL-17A-producing canine MoDCs and CD4 + T cells producing IFN-γ and IL-17A., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Protein methyltransferases (PMTs) comprise a major class of epigenetic regulatory enzymes with therapeutic relevance. Here we present a collection of chemical probes and associated reagents and data to elucidate the function of human and murine PMTs in cellular studies. Our collection provides inhibitors and antagonists that together modulate most of the key regulatory methylation marks on histones H3 and H4, providing an important resource for modulating cellular epigenomes. We describe a comprehensive and comparative characterization of the probe collection with respect to their potency, selectivity, and mode of inhibition. We demonstrate the utility of this collection in CD4 + T cell differentiation assays revealing the potential of individual probes to alter multiple T cell subpopulations which may have implications for T cell-mediated processes such as inflammation and immuno-oncology. In particular, we demonstrate a role for DOT1L in limiting Th1 cell differentiation and maintaining lineage integrity. This chemical probe collection and associated data form a resource for the study of methylation-mediated signaling in epigenetics, inflammation and beyond.

Immune cells are known as the most sensitive tissue for ionizing radiation. Numerous reports relating with the effect of low-dose ionizing radiation (LDIR) on immune activities showed that LDIR can induce immune-potentiation via modulating the activity of B-, T-, and NK cells, or macrophages, whereas high-dose radiation induces genome-wide apoptotic/necrotic tissue injury and immune suppression. Generally, CD4 + T-cells play pivotal roles in immune systems via cytokines and cell-surface molecules to activate other types of immune cells to eliminate the pathogen. In spite of the significance of CD4 + T-cells in the immune system, mechanism of how LDIR regulates CD4 + T-cell gene expression is poorly investigated. Thus, RNA-Seq and Gene-Set Enrichment Analysis (GSEA) analysis were done with low-dose irradiated (γ-radiation, 50 mGy, 204 mGy/h)/anti-CD3/CD28-stimulated CD4 + T-cells to explore the LDIR-specific regulation of CD4 + T-cell gene expression. The results indicated that the genes related to mRNA translation processes, mitochondrial function, cell cycle regulation, and cytokine induction were upregulated in irradiated cells. Moreover, this study showed that the expression of T-helper cell Type 1 (T H 1) or type 2 (T H 2) cytokine genes, such as those for interferon (IFN)-γ, interleukin (IL)-4, and IL-5 were increased by at least 1.4-fold in acute (204 mGy/h) or chronic (10 mGy/h) low-dose (10 or 50 mGy) irradiated/anti-CD3/CD28 stimulated CD4 + T-cells, whereas the T-regulatory (T reg ) cell cytokine gene, transforming growth factor (TGF)-β was decreased. Overall, these findings demonstrated that LDIR could cause an upregulation of selected immune product genes and, in turn, might modulate the activity of CD4 + T-cells undergoing activation via an impact on cytokine gene regulation.

Background: Human regulatory T cells (Tregs) are a heterogeneous population which consists of three distinct subpopulations: CD25 + CD45RA + resting Treg (rTreg) cells; CD25 hi CD45RA - activated Treg (aTreg) cells, which are both suppressive; and CD25 + CD45RA - cytokine-secreting T cells with pro-inflammatory capacity., Objective: We investigated variation in peripheral Treg subpopulations of asthma and explored their potential roles in asthma inflammation., Methods: Twenty-eight mild asthma patients, 26 moderate asthma patients, 18 severe asthma patients, and 36 healthy controls were recruited for a cross-sectional study. Phenotyping of peripheral CD4 + Tregs was performed based on flow cytometry results., Results: The proportions of rTreg and aTreg cells among CD4 + T cells were higher in mild and moderate asthma patients than in healthy controls. All three groups of asthmatics had a higher proportion of pro-inflammatory Tregs than healthy controls, and these increased with asthma severity. The proportion of IL-17-producing Foxp3 + cells and IFN-ɤ-producing Foxp3 + cells strongly correlated with T helper 17 (Th17) cells (r = 0.66, p < 0.001) and Th1 cells (r = 0.48, p < 0.001). The pro-inflammatory Treg subpopulation was correlated with the severity of asthma and may be insensitive to corticosteroids., Conclusions: Our data suggest that pro-inflammatory Treg subpopulations may be relevant to the plasticity of Th17 and Th1 differentiation and play an important role in the pathogenesis of asthma., (Copyright © 2018. Published by Elsevier Ltd.)

Monoallelic loss-of-function mutations in NFKB1 were recently recognized as the most common monogenic cause of common variable immunodeficiency (CVID). The prototypic clinical phenotype of NFKB1-deficient patients includes common CVID features, such as hypogammaglobulinaemia and sinopulmonary infections, plus other highly variable individual manifestations. Here, we describe a patient with a profound CVID phenotype and severe gastrointestinal manifestations, including chronic and recurrent diarrhoea. Using an NGS customized panel of 323 genes related to primary immunodeficiencies, we identified a novel monoallelic loss-of-function mutation in NFKB1 leading to a truncated protein (c.1149delT/p.Gly384Glu ∗ 48). Interestingly, we also found a rare variant in NOD2 previously associated with Crohn's disease (p.His352Arg). Our patient had hypogammaglobulinaemia with a small number of B cells, most of which were naïve. The most noteworthy findings included marked skewing towards a Th1 phenotype in peripheral blood T cells and excessive production of proinflammatory cytokines (IL-1β, TNFα). The patient's 6-year-old daughter, a carrier of the NFKB1 mutation, is clinically asymptomatic, but has started to show cellular and molecular changes. This case of NFKB1 deficiency appears to be a combination of immunodeficiency and a hyperinflammatory state. The current situation of the patient's daughter provides a glimpse of the preclinical phase of the condition., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Hashimoto's thyroiditis (HT) is considered a T helper-type 1 (Th1) cytokine-dominant autoimmune thyroid disease. Caveolin-1 (Cav-1), a part of the thyroxisome multiprotein complex, is localized at the apical pole of thyrocytes and is indispensable for synthesis of thyroid hormones and modulation of oxidative stress in order to avoid cell damage and apoptosis. Reduced autophagy induces thyroid follicular cells (TFC) apoptosis by activating reactive oxygen species (ROS) in HT patients. Nevertheless, whether Cav-1 has roles in the regulation of autophagy remains largely unclear. In this study, we examined Th1 cytokines and Cav-1 expression in HT thyroid tissues, determined the effects of interleukin-1beta (IL-1β) and interferon-gamma (IFN-γ) on Cav-1 and autophagy activity in TFC, and investigated the association between Cav-1 and autophagy activity in vitro. Our results indicate that higher levels of IL-1β and IFN-γ and lower levels of Cav-1 were expressed in thyroid tissues of HT patients than in those of normal controls. Cav-1 mRNA and protein levels were significantly decreased in TFC exposed to IL-1β and IFN-γ, accompanied by decreased expression of autophagy-related protein LC3B-II. Interestingly, small interfering RNA (siRNA)-mediated Cav-1 knockdown in TFC reduced LC3B-II protein expression. Taken together, these results suggest that lack of Cav-1 expression inhibited autophagy activity in TFC exposed to Th1 cytokines (IL-1β and IFN-γ), which might be a novel pathogenetic mechanism of HT.

Multiple sclerosis is an autoimmune disease that is caused by the interplay of genetic, particularly the HLA-DR15 haplotype, and environmental risk factors. How these etiologic factors contribute to generating an autoreactive CD4 + T cell repertoire is not clear. Here, we demonstrate that self-reactivity, defined as "autoproliferation" of peripheral Th1 cells, is elevated in patients carrying the HLA-DR15 haplotype. Autoproliferation is mediated by memory B cells in a HLA-DR-dependent manner. Depletion of B cells in vitro and therapeutically in vivo by anti-CD20 effectively reduces T cell autoproliferation. T cell receptor deep sequencing showed that in vitro autoproliferating T cells are enriched for brain-homing T cells. Using an unbiased epitope discovery approach, we identified RASGRP2 as target autoantigen that is expressed in the brain and B cells. These findings will be instrumental to address important questions regarding pathogenic B-T cell interactions in multiple sclerosis and possibly also to develop novel therapies., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: Among individual depressive symptoms, anhedonia has been reliably associated with activation of the innate immune response. However, it is unclear whether this association extends to T cell cytokines and if gender differentially affects this association., Method: Concentrations of T (IL-17, T-helper (Th) 1- and Th2-) and non-T cell cytokines were measured in plasma using the Bioplex Pro™ human cytokine multiplex kit in Combining Medications to Enhance Depression Outcomes (CO-MED) trial participants who provided plasma at baseline (n = 166). Anhedonia was measured with three items of the clinician-rated Inventory of Depressive Symptomatology and depression severity (minus anhedonia item) was measured with Quick Inventory of Depression Severity Self-Report version (modified-QIDS-SR). Separate generalized linear models for anhedonia and modified-QIDS-SR as dependent variables were conducted with IL-17, Th1-, Th2-, and non-T cell- cytokines as primary independent variables and gender, body mass index (BMI), and age as covariates. Exploratory analyses included gender-by-biomarker interactions., Results: Higher levels of IL-17 (p = 0.032), Th1- (p = 0.002), Th2-(p = 0.001) and non-T-(p = 0.009) cell markers were associated with greater severity of anhedonia controlling for BMI, age, and gender. Gender also had a significant main effect on anhedonia, however, there was a significant gender by immune marker interaction only for IL-17 (p = 0.050). Anhedonia severity increased with higher IL-17 in males (r = 0.42, p = 0.003) but not in females (r = 0.09, p = 0.336). Only non-T cell markers were associated with the modified-QIDS-SR, and there were no significant gender-specific associations with this variable., Conclusions: T and non-T cell-related inflammatory markers were associated with greater severity of anhedonia, while gender moderated the association of IL-17 with anhedonia in patients with major depressive disorder., (Copyright © 2018. Published by Elsevier Ltd.)

IL-35, a novel IL-12 family member, is a potent inhibitory cytokine predominantly produced by regulatory T and B lymphocytes that exerts optimal suppression in immune response. However, it remains unclear whether IL-35 plays an inhibitory role on human dendritic cells. In the present study, we focused on the possible immunosuppressive effect of IL-35 on the differentiation, maturation and function of monocyte-derived DCs (MoDCs). Addition of exogenous IL-35 was able to partially suppress MoDCs differentiation in vitro. Subsequently, LPS was used for the maturation of MoDCs and IL-35 was found to mainly restrain the maturation of MoDCs, characterized by the remarkable down-regulation of costimulatory molecules, CD83 and HLA-DR as well as a reduced production of pro-inflammatory cytokines (IL-12p70, IFN-γ, and TNF-α). Furthermore, IL-35-treated MoDCs exhibited strong inhibition in the proliferation of allogeneic CD4 + /CD8 + T lymphocytes. Meanwhile, IL-35-treated MoDCs also suppressed the polarization of naïve CD4 + T lymphocytes towards Th1 phenotype and impaired CD8 + T cells allogeneic responses. And the foregoing suppression of MoDCs maturation and function by IL-35 might be due to the aberrant activation of STAT1/STAT3 and inhibition of p38 MAPK/NF-κB signaling pathway. Our results demonstrated for the first time that IL-35 played a critical role in modulating not only adaptive immune response, but also innate immune response. The inhibitory effect of IL-35 on MoDCs maturation and function may facilitate the development of promising therapeutic interventions in tumors and other diseases., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The magnitude of immune responses to vaccination is a critical factor in determining protection from disease. It is known that cigarette smoke dampens the immune system and increases the risk of vaccine-preventable diseases. We reported that nicotine, the immunosuppressive component of cigarette smoke, disrupts the differentiation and functional properties of DC, which are pivotal in the initiation of immune response to vaccines. We also reported that TLR agonists act in synergy and boost DC maturation, DC-NK crosstalk and ultimately naïve T cell polarization into effector Th1 and Tc1 cells. Here, we investigated whether the combination of TLR agonists could diminish the degrading effects of nicotine on DC-NK mediated effector T cell generation. We found that none of TLR agonists, single or combined, were able to diminish completely the adverse effects of nicotine on DC. However, TLR3, TLR4, and TLR8 agonists acted as the most effective adjuvants to increase the expression levels of antigen-presenting, costimulatory molecules and production of cytokines by nicotine-exposed DC (nicDC). When combined, TLR3 + 8 and TLR4 + 8 synergistically optimized nicDC maturation and IFN-γ secretion from nicotine-exposed NK (nicNK) during co-cultures. Interestingly, in contrast to DC-NK-T, co-cultures of nicDC-nicNK-T treated with TLR3 + 8 or TLR4 + 8 agonists produced a similar frequency of effector memory Th1 and Tc1 cells. However, the effector cells from TLR4 + 8 followed by TLR3 + 8 treated nicDC-nicNK-T co-cultures produced significantly more IFN-γ when compared with aluminum salt treated co-culture. Our data suggest that addition of appropriate TLR agonists to vaccine formulation could potentially augment the immune response to vaccination in smokers., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Various clinical, biologic, or physiologic markers of asthma have been used to identify patient clusters and potential targets for therapy. However, these identifiers frequently overlap among the different asthma groups. For instance, both eosinophil and neutrophil counts are often increased in the airways of asthmatic patients despite their typical association with type 2 and type 17 immune response, respectively., Objectives: We sought to determine whether inflammatory gene expression is related to patterns of airway inflammation and lung function and identify molecular markers for neutrophilic asthma., Methods: Expression levels of 17 genes characterizing type 1, type 2, and type 17 lymphocytes were measured in sputum samples from 48 participants with asthma. The relationships between gene expression levels and sputum cell differentials or measures of pulmonary function were examined by using partial least squares regression., Results: Gene expression levels were strongly associated with cell differentials, explaining 71% of variation in eosinophil counts and 64% of variation in neutrophil counts. The 3 genes with the strongest relationships to sputum neutrophil counts were IL1R1 (standardized regression coefficient [β] = +0.27, P = .005), IL1RAP (β = +0.32, P = .0004), and IL4R (β = +0.29, P = .002). Higher expression levels of IL1R1, IL1RAP, and IL4R were associated with reduced FEV 1 /forced vital capacity ratio (β = -0.11, -0.08, and -0.10; P = .005, .07, and .05)., Conclusion: IL-1 receptor appears to be a marker of neutrophilic inflammation and airflow obstruction in patients with asthma, who have a wide range of disease severity. The IL-1 pathway might contribute to airway neutrophilia and is a potential therapeutic target in patients with neutrophilic asthma., (Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Leukocyte-associated Ig-like receptor 1 (LAIR1) is an ITIM-bearing collagen receptor expressed by leukocytes and is implicated in immune suppression. However, using a divalent soluble LAIR1/Fc recombinant protein to block interaction of cell surface LAIR1 with matrix collagen, we found that whereas T h 1 responses were enhanced as predicted, T h 17 responses were strongly inhibited. Indeed, LAIR1 on both T cells and monocytes was required for optimal T h 17 responses to collagen type (Col)V. For pre-existing "natural" T h 17 response to ColV, the LAIR1 requirement was absolute, whereas adaptive T h 17 and T h 1/17 immune responses in both mice and humans were profoundly reduced in the absence of LAIR1. Furthermore, the addition of C1q, a natural LAIR1 ligand, decreased T h 1 responses in a dose-dependent manner, but it had no effect on T h 17 responses. In IL-17-dependent murine organ transplant models of chronic rejection, LAIR1 +/+ but not LAIR1 -/- littermates mounted strong fibroproliferative responses. Surface LAIR1 expression was higher on human T h 17 cells as compared with T h 1 cells, ruling out a receptor deficiency that could account for the differences. We conclude that LAIR1 ligation by its natural ligands favors T h 17 cell development, allowing for preferential activity of these cells in collagen-rich environments. The emergence of cryptic self-antigens such as the LAIR1 ligand ColV during ischemia/reperfusion injury and early acute rejection, as well as the tendency of macrophages/monocytes to accumulate in the allograft during chronic rejection, favors T h 17 over T h 1 development, posing a risk to long-term graft survival., (Copyright © 2018 by The American Association of Immunologists, Inc.)

Background: Imbalance of interferon-gamma (IFN-γ), interleukin (IL)-4, and IL-17 producing by T cells is confirmed to contribute to the pathogenesis of systemic lupus erythematosus (SLE). Autophagy is now emerging as a core player in the development and the function of the immune system. Therefore, we investigated the autophagic behavior in IFN-γ-, IL-4-, and IL-17-producing T cells from patients with SLE., Methods: Thirty patients with SLE and 25 healthy controls matched for gender and age were recruited between September 2016 and May 2017. The autophagic levels in IFN-γ + T cells, IL-4 + T cells, and IL-17 + T cells from patients with newly diagnosed SLE and healthy controls were measured using flow cytometry. The plasma levels of IFN-γ were determined by enzyme-linked immunosorbent assay in SLE patients and healthy controls. Unpaired t-tests and the nonparametric Mann-Whitney U-test were used to compare data from patients with SLE and controls. Spearman's rank correlation coefficient was applied for calculation of the correlation between parallel variables in single samples., Results: Our results showed increased percentage of autophagy in IFN-γ + T cells from patients with SLE and healthy controls ([8.07 ± 2.72]% vs. [3.76 ± 1.67]%, t = 5.184, P < 0.001), but not in IL-4 + T cells or IL-17 + T cells (P > 0.05) as compared to healthy donors. Moreover, the plasma levels of IFN-γ in SLE patients were significantly higher than those in healthy controls ([68.9 ± 29.1] pg/ml vs. [24.7 ± 17.6] pg/ml, t = 5.430, P < 0.001). Moreover, in SLE patients, the percentage of autophagy in IFN-γ + T cells was positively correlated with the plasma levels of IFN-γ (r = 0.344, P = 0.046), as well as the disease activity of patients with SLE (r = 0.379, P = 0.039)., Conclusion: The results indicate that autophagy in IFN-γ + T cells from SLE patients is activated, which might contribute to the persistence of T cells producing IFN-γ, such as Th1 cells, and consequently result in the high plasma levels of IFN-γ, and then enhance the disease activity of SLE., Competing Interests: There are no conflicts of interest

Objective: In systemic lupus erythematosus (SLE), an autoimmune disease associated with multiple organ involvement, the development of lupus nephritis determines prognosis, and arthritis impairs quality of life. Galectin 9 (Gal-9, Lgals9) is a β-galactoside-binding lectin that has been used for clinical application in autoimmune diseases, since recombinant Gal-9, as a ligand for T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), induces apoptosis of activated CD4+TIM-3+ Th1 cells. This study was undertaken to investigate whether deficiency of Lgals9 has beneficial or deleterious effects on lupus in a murine model., Methods: Gal-9 +/+ and Gal-9 -/- female BALB/c mice were injected with pristane, and the severity of arthritis, proteinuria, and levels of autoantibody production were assessed at several time points immediately following injection. At 7 months after pristane injection, renal pathologic features, the severity of joint inflammation, and formation of lipogranulomas were evaluated. Subsets of inflammatory cells in the spleen and peritoneal lavage were characterized, and expression levels of cytokines from peritoneal macrophages were analyzed., Results: Lgals9 deficiency protected against the development of immune complex glomerulonephritis, arthritis, and peritoneal lipogranuloma formation in BALB/c mice in this murine model of pristane-induced lupus. The populations of T cell subsets and B cells in the spleen and peritoneum were not altered by Lgals9 deficiency in pristane-injected BALB/c mice. Furthermore, Lgals9 deficiency protected against pristane-induced lupus without altering the Toll-like receptor 7-type I interferon pathway., Conclusion: Gal-9 is required for the induction and development of lupus nephritis and arthritis in this murine model of SLE. The results of the current investigation provide a potential new strategy in which antagonism of Gal-9 may be beneficial for the treatment of nephritis and arthritis in patients with SLE through targeting of activated macrophages., (© 2018, American College of Rheumatology.)

CCDC134 (coiled-coil domain containing 134), a cytokine-like molecule, was previously reported to exert antitumor effects by augmenting CD8 + T-cell mediated immunity. However, the dynamic changes in CCDC134 expression patterns in the spinal cord that may be involved in the progression of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis, remains unclear. In this study, we found that CCDC134 expression was markedly increased in the spinal cord during the progression of EAE. Furthermore, we demonstrated that CCDC134 significantly reduced the severity and slowed the progression of EAE, which correlated with reduced spinal cord inflammation and demyelination. The underlying mechanism of CCDC134-induced effects involved inhibition of T helper (Th)-1 and Th17 cell differentiation and secretion of its key effector molecules IFN-γ and IL-17A via regulation of JAK/STAT signaling. These findings indicate that CCDC134 exerts potent anti-inflammatory effects through the selective modulation of pathogenic Th1 and Th17 cells by targeting critical signaling pathways. The study provides insights into the role of CCDC134 as a unique therapeutic agent for the treatment of autoimmune diseases., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Importance: In spite of progress in understanding the mechanisms underlying hidradenitis suppurativa (HS) as an inflammatory skin disease, there is still a demand for an overview on immunopathogenesis of HS., Objective: To demonstrate the importance of the type 1/type 17 immune response in lesional HS skin by drawing a semantic connectivity map., Design, Setting, and Participants: Single-center case series of 24 patients with HS. Association of HS with T helper 1/T helper 17 (TH1/TH17) phenotype was assessed using semantic map analysis., Main Outcomes and Measures: Association of HS with TH1/TH17 phenotype., Results: The analysis was performed on 24 lesional HS biopsy samples from untreated patients with HS (16 [67%] female; median age, 36.5 years [range, 21-51 years]) with a mean (SD) Hurley stage of 2.29 (0.62) and 9 punch biopsy samples from healthy controls (6 [67%] female; median age, 43 years [range, 23-66 years]). The map shows a clustering of all TH1/TH17-associated cytokines (interleukin 17 [IL-17], interferon γ, IL-12, IL-23, IL-32, IL-1β, tumor necrosis factor) around overall lesional inflammation. Tumor necrosis factor, IL-12, and IL-17 are even directly connected via interferon γ. In contrast, IL-13, a TH2-associated cytokine, was inversely correlated with the presence of TH1/TH17-associated cytokines, further highlighting the importance of the TH1/TH17 cytokines in HS pathogenesis., Conclusions and Relevance: These findings suggest that HS may be a TH1/TH17-driven inflammatory skin disease.

In T lymphocytes, expression of miR-148a is induced by T-bet and Twist1, and is specific for pro-inflammatory Th1 cells. In these cells, miR-148a inhibits the expression of the pro-apoptotic protein Bim and promotes their survival. Here we use sequence-specific cholesterol-modified oligonucleotides against miR-148a (antagomir-148a) for the selective elimination of pro-inflammatory Th1 cells in vivo. In the murine model of transfer colitis, antagomir-148a treatment reduced the number of pro-inflammatory Th1 cells in the colon of colitic mice by 50% and inhibited miR-148a expression by 71% in the remaining Th1 cells. Expression of Bim protein in colonic Th1 cells was increased. Antagomir-148a-mediated reduction of Th1 cells resulted in a significant amelioration of colitis. The effect of antagomir-148a was selective for chronic inflammation. Antigen-specific memory Th cells that were generated by an acute immune reaction to nitrophenylacetyl-coupled chicken gamma globulin (NP-CGG) were not affected by treatment with antagomir-148a, both during the effector and the memory phase. In addition, antibody titers to NP-CGG were not altered. Thus, antagomir-148a might qualify as an effective drug to selectively deplete pro-inflammatory Th1 cells of chronic inflammation without affecting the protective immunological memory., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Regulatory T cells (Treg) can show plasticity whereby FOXP3 expression, the master transcription factor for Treg suppressor function, is lost and proinflammatory cytokines are produced. Optimal FOXP3 expression strongly depends on hypomethylation of the FOXP3 gene. 5-Azacytidine (Aza) and its derivative 5-aza-2'-deoxycytidine (DAC) are DNA methyltransferase inhibitors (DNMTi) that are therapeutically used in hematological malignancies, which might be an attractive strategy to promote Treg stability. Previous in vitro research primarily focused on Treg induction by DAC from naïve conventional CD4 + T cells (Tconv). Here, we examined the in vitro effect of DAC on the stability and function of FACS-sorted human naturally occurring CD4 + CD25 high FOXP3 + Treg. We found that in vitro activation of Treg in the presence of DAC led to a significant inhibition of Treg proliferation, but not of Tconv. Although Treg activation in the presence of DAC led to increased IFN γ expression and induction of a Thelper-1 phenotype, the Treg maintained their suppressive capacity. DAC also induced a trend towards increased IL-10 expression. In vivo studies in patients with hematological malignancies that were treated with 5-azacytidine (Vidaza) supported the in vitro findings. In conclusion, despite its potential to increase IFN γ expression, DAC does preserve the suppressor phenotype of naturally occurring Treg.

Protective efficacy of Bacillus Calmette-Guérin (BCG) may be affected by the methods and routes of vaccine administration. We have studied the safety and immunogenicity of oral (PO) and/or intradermal (ID) administration of BCG in healthy human subjects. No major safety concerns were detected in the 68 healthy adults vaccinated with PO and/or ID BCG. Although both PO and ID BCG could induce systemic Th1 responses capable of IFN-γ production, ID BCG more strongly induced systemic Th1 responses. In contrast, stronger mucosal responses (TB-specific secretory IgA and bronchoalveolar lavage T cells) were induced by PO BCG vaccination. To generate preliminary data comparing the early gene signatures induced by mucosal and systemic BCG vaccination, CD4 + memory T cells were isolated from subsets of BCG vaccinated subjects pre- (Day 0) and post-vaccination (Days 7 and 56), rested or stimulated with BCG infected dendritic cells, and then studied by Illumina BeadArray transcriptomal analysis. Notably, distinct gene expression profiles were identified both on Day 7 and Day 56 comparing the PO and ID BCG vaccinated groups by GSEA analysis. Future correlation analyses between specific gene expression patterns and distinct mucosal and systemic immune responses induced will be highly informative for TB vaccine development.

IL-10 is a pleiotropic cytokine with multifaceted functions in establishing immune homeostasis. Although expressed by Th1 and Th2 cells, conventional Th1 cells produce marginal levels of IL-10 compared with their Th2 counterparts. In this study, we investigated the epigenetic mechanisms of Il-10 gene expression in Th1 cells. Bioinformatics EMBOSS CpG plot analysis and bisulfite pyrosequencing revealed three CpG DNA methylation sites in the Il-10 gene locus. Progressive DNA methylation at all of the CpG regions of interest (ROIs) established a repressive program of Il-10 gene expression in Th1 cells. Interestingly, Th1 cells treated with IL-12 and IL-27 cytokines, thereby mimicking a chronic inflammatory condition in vivo, displayed a significant increase in IL-10 production that was accompanied by selective DNA demethylation at ROI 3 located in intron 3. IL-10-producing T cells isolated from lymphocytic choriomeningitis virus-infected mice also showed enhanced DNA demethylation at ROI 3. Binding of STAT1 and STAT3 to demethylated ROI 3 enhanced IL-10 expression in an IL-12/IL-27-dependent manner. Accordingly, CD4 + T cells isolated from STAT1- or STAT3-knockout mice were significantly defective in IL-10 production. Our data suggest that, although stably maintained DNA methylation at the promoter may repress IL-10 expression in Th1 cells, locus-specific reversible DNA demethylation may serve as a threshold platform to control transient Il-10 gene expression., (Copyright © 2018 by The American Association of Immunologists, Inc.)

Cryptococcosis, caused by Cryptococcus neoformans, has been demonstrated to be controlled by T helper (Th)1 cells while Th2 cells are associated with fungal growth and dissemination. Although cryptococcal immunoreactive protein antigens were previously identified, their association with Th1 or Th2 immune responses was not provided. In mice, Th1-dependent IFN-γ induces the production of IgG2a, whereas the Th2 cytokine IL-4 stimulates the expression of IgG1 rendering each isotype an indicator of the underlying Th cell response. Therefore, we performed an immunoproteomic study that distinguishes Th1- and Th2-associated antigens by their reactivity with Th1-dependent IgG2a or Th2-dependent IgG1 antibodies in sera from C. neoformans-infected wild-type mice. We additionally analysed sera from Th2-prone IL-12-deficient and Th1-prone IL-4Rα-deficient mice extending the results found in wild-type mice. In total, ten, four, and three protein antigens associated with IgG1, IgG2a, or both isotypes, respectively, were identified. Th2-associated antigens represent promising candidates for development of immunotherapy regimens, whereas Th1-associated antigens may serve as candidates for vaccine development. In conclusion, this study points to intrinsic immunomodulatory effects of fungal antigens on the process of Th cell differentiation based on the identification of cryptococcal protein antigens specifically associated with Th1 or Th2 responses throughout mice of different genotypes.

Leprosy is an infectious disease caused by non-cultivable bacteria Mycobacterium leprae. Ridley and Jopling classified the disease into five polar forms, Tuberculoid (TT) and Lepromatous (LL), in between two forms of the disease Borderline tuberculoid (BT), Borderline (BB) and Borderline lepromatous (BL) are laid. The tuberculoid type (BT/TT) leprosy patients show good recall of cellmediated immune (CMI) response and Th1 type of immune response, while lepromatous leprosy (LL) patients show defect in cell-mediated immunity to the causative agent and Th2 type of immune response. Due to distinct clinical and immunological spectra of the disease, leprosy attracted immunologists to consider an ideal model for the study of deregulations of various immune reactions. Recent studies show that Tregs, Th3 (TGF-β, IL-10), IL-35 producing Treg immune response associated with the immune suppressive environment, survival of bugs. IL-17 producing Th17 immune response associated with tuberculoid leprosy and play protective role. γδ T cells also increased from tuberculoid to lepromatous pole of leprosy. In this review, we will discuss the role of various subtypes of T-cell and their cytokines in the pathogenesis of leprosy., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background: Canine visceral leishmaniasis (CVL) caused by Leishmania infantum is endemic in the northwest and south of Iran. An appropriate vaccine can help to prevent and control visceral leishmaniasis in both humans and animals. Few studies have confirmed that the fucose-mannose ligand (FML) antigen of Leishmania donovani produced protective immunity in dogs against CVL., Objective: To evaluate the immune responses of vaccinated dogs against FML antigen of L. infantum., Methods: We isolated the FML antigen from native L. infantum and vaccinated the dogs with FML-saponin in an endemic area of VL in Iran to evaluate the immune responses of vaccinated dogs against this antigen., Results: Our results indicated a significant increase in the expression of IFN-γ, IL-10 and IL-13, but not IL-12A, gene transcripts in PBMCs of FML-saponin vaccinated dogs in comparison with controls. Our findings showed a significant difference in the ratio of IFN-γ/IL-10 mRNA expression in FML-saponin vaccinated dogs in comparison with two control groups. Moreover, a significant level of anti-FML antibodies was detected in serum of vaccinated dogs., Conclusion: These findings showed that FML-saponin stimulates both Th1 and Th2 immune responses with predominant Th1 and strong humoral immune responses to produce protective immunity against CVL.

B cells give rise to polarized subsets, including B effector 1 (Be1) cells and regulatory B cells, which can promote or inhibit immune responses through expression of IFN-γ and IL-10, respectively. Such subsets likely explain why B cell depletion can either ameliorate or exacerbate inflammatory diseases; however, these cells remain poorly understood because of the absence of specific markers. Although T cell Ig and mucin domain-containing molecule (TIM)-1 broadly identifies IL-10 + regulatory B cells, no similar markers for Be1 cells have been described. We now show that TIM-4 is expressed by a subset of B cells distinct from those expressing TIM-1. Although TIM-1 + B cells are enriched for IL-10, TIM-4 + B cells are enriched for IFN-γ. TIM-1 + B cells enhanced the growth of B16-F10 melanoma. In contrast, TIM-4 + B cells decreased B16-F10 metastasis and s.c. tumor growth, and this was IFN-γ dependent. TIM-1 + B cells prolonged islet allograft survival in B-deficient mice, whereas TIM-4 + B cells accelerated rejection in an IFN-γ-dependent manner. Moreover, TIM-4 + B cells promoted proinflammatory Th differentiation in vivo, increasing IFN-γ while decreasing IL-4, IL-10, and Foxp3 expression by CD4 + T cells-effects that are opposite from those of TIM-1 + B cells. Importantly, a monoclonal anti-TIM-4 Ab promoted allograft tolerance, and this was dependent on B cell expression of TIM-4. Anti-TIM-4 downregulated T-bet and IFN-γ expression by TIM-4 + B cells and indirectly increased IL-10 expression by TIM-1 + B cells. Thus, TIM-4 + B cells are enriched for IFN-γ-producing proinflammatory Be1 cells that enhance immune responsiveness and can be specifically targeted with anti-TIM-4., (Copyright © 2017 by The American Association of Immunologists, Inc.)

The p38 mitogen-activated protein kinase (MAPK) pathway is involved in the regulation of immune and inflammatory processes. We used p38α-conditional, p38β-deficient and p38α/β double-null mouse models to address the role of these two p38 MAPK in CD4 + T cells, and found that p38α deficiency causes these cells to hyperproliferate. Our studies indicate that both p38α and p38β are dispensable for T helper cell type 1 (Th1) differentiation but, by controlling interferon (IFN)γ and tumor necrosis factor (TNF)α production, are critical for normal Th1 effector function. We found that both p38α and p38β modulate T-cell receptor-induced IFNγ and TNFα production, whereas only p38α regulates cytokine-induced IFNγ production. The lack of p38α and p38β did not affect transcription and mRNA stability of Ifng. However, the absence of p38α in Th1 cells resulted in a decreased MNK1 phosphorylation after cytokine activation, and MNK1 inhibition blocked IFNγ production. Our results indicate that p38α regulates IFNγ secretion through the activation of the MNK1/eIF4E pathway of translation initiation and identify specific functions for p38α and p38β in T-cell proliferation.

The α L β 2 integrin LFA-1 is known to play a key role in T lymphocyte migration, which is necessary to mount a local immune response, and is also the main driver of autoimmune diseases. This migration-triggering signaling process in T cells is tightly regulated to permit an immune response that is appropriate to the local trigger, as well as to prevent deleterious tissue-damaging bystander effects. Emerging evidence shows that, in addition to prompting a diverse range of downstream signaling cascades, LFA-1 stimulation in T lymphocytes modulates gene-transcription programs, including genetic signatures of TGF-β and Notch pathways, with multifactorial biological outcomes. This review highlights recent findings and discusses molecular mechanisms by which LFA-1 signaling influence T lymphocyte differentiation into the effector subsets Th1, Th17, and induced regulatory T cells. We argue that LFA-1 contact with a cognate ligand, such as ICAM-1, independent of the immune synapse activates a late divergence in T cells' effector phenotypes, hence fine-tuning their functioning., (Copyright © 2017 by The American Association of Immunologists, Inc.)

Ocular infection with HSV causes a chronic T cell-mediated inflammatory lesion in the cornea. Lesion severity is affected by the balance of different CD4 T cell subsets, with greater severity occurring when the activity of regulatory T cells (Tregs) is compromised. In this study, fate-mapping mice were used to assess the stability of Treg function in ocular lesions. We show that cells that were once Foxp3 + functional Tregs may lose Foxp3 and become Th1 cells that could contribute to lesion expression. The instability primarily occurred with IL-2R lo Tregs and was shown, in part, to be the consequence of exposure to IL-12. Lastly, in vitro-generated induced Tregs (iTregs) were shown to be highly plastic and capable of inducing stromal keratitis when adoptively transferred into Rag1 -/- mice, with 95% of iTregs converting into ex-Tregs in the cornea. This plasticity of iTregs could be prevented when they were generated in the presence of vitamin C and retinoic acid. Importantly, adoptive transfer of these stabilized iTregs to HSV-1-infected mice prevented the development of stromal keratitis lesions more effectively than did control iTregs. Our results demonstrate that CD25 lo Treg and iTreg instability occurs during a viral immunoinflammatory lesion and that its control may help to avoid lesion chronicity., (Copyright © 2017 by The American Association of Immunologists, Inc.)

Th2 cell differentiation involves complex changes in expression of multiple genes, many of which have poorly characterized roles. In a gene expression microarray analysis of human primary CD4 + effector T subsets, we identified that an adaptor protein, GAB2, was preferentially expressed in human Th2 cells. The role of GAB2 in human Th2 cells is unknown. Through analysis of primary and in vitro differentiated human T effector subsets, we confirmed that human Th2 cells preferentially expressed GAB2. Further analysis of public gene expression microarray data of STAT6-knockdowned Th2 cells indicated that GAB2 expression was regulated by IL-4 and STAT6. Both siRNA knockdown and ectopic expression of GAB2 in activated T cells showed that GAB2 positively regulated IL-4 and IL-13 expression in human Th2 cells. We hence identified the adaptor protein, GAB2, as an important novel regulator of the human Th2 immune response., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Protein expression is disturbed in the psoriatic stratum corneum (SC). Noninvasive methods for the description of pathophysiological changes and drug profiling in psoriasis are desirable., Objectives: Undertake large-scale noninvasive protein expression studies in psoriatic SC to identify biomarkers of pathophysiological processes and use them for drug profiling., Methods: Psoriatic SC was harvested through repetitive tape-stripping. Nonlesional and lesional SC, as well as vehicle-treated and drug-treated lesional SC samples were collected. Protein extracts from nonlesional and lesional skin biopsies were used for comparison. Calcipotriol-betamethasone (CB) was used as a reference medication. Proteins extracted from pooled tape strips were quantified using mass spectrometry (MS), Western blotting, enzyme-linked immunosorbent assay and Luminex technologies., Results: MS-based methods identified 140 proteins differentially expressed in psoriatic SC. Epidermis development, glycolysis, regulation of apoptosis, cytoskeleton organization and peptide cross-linking were modulated, all reflecting perturbed epidermal differentiation. Using antibody-based techniques, increased levels of sICAM1, of CXCL1- and CXCL8-attracting neutrophils, of CXCL10- and CCL4-attracting T helper (Th) 1 cells, and of CCL2- and CCL4-attracting monocytes and dendritic cells were observed. Quantification of the Th1 and Th17 markers tumour necrosis factor, interleukin (IL) 12B, IL17A and IL17F in lesional SC was successful, while the Th2 cytokines IL4, IL5 and IL13, not involved in the disease process, were not detected. The pruritic cytokine IL31 was detected in lesional SC. CXCL1, CXCL8, CXCL10 and sICAM were used to investigate disease remission, ranking three topical treatments according to their known clinical efficacy., Conclusions: Protein biomarker quantification in psoriatic SC detects key pathophysiological mechanisms and enables noninvasive drug profiling in translational medicine settings., (© 2017 British Association of Dermatologists.)