Transcriptional and methylation outcomes of didehydro-cortistatin A use in HIV-1-infected CD4+ T cells.

Ongoing viral transcription from the reservoir of HIV-1 infected long-lived memory CD4+ T cells presents a barrier to cure and associates with poorer health outcomes for people living with HIV, including chronic immune activation and inflammation. We previously reported that didehydro-cortistatin A (dCA), an HIV-1 Tat inhibitor, blocks HIV-1 transcription. Here, we examine the impact of dCA on host immune CD4+ T-cell transcriptional and epigenetic states. We performed a comprehensive analysis of genome-wide transcriptomic and DNA methylation profiles upon long-term dCA treatment of primary human memory CD4+ T cells. dCA prompted specific transcriptional and DNA methylation changes in cell cycle, histone, interferon-response, and T-cell lineage transcription factor genes, through inhibition of both HIV-1 and Mediator kinases. These alterations establish a tolerogenic Treg/Th2 phenotype, reducing viral gene expression and mitigating inflammation in primary CD4+ T cells during HIV-1 infection. In addition, dCA suppresses the expression of lineage-defining transcription factors for Th17 and Th1 cells, critical HIV-1 targets, and reservoirs. dCA's benefits thus extend beyond viral transcription inhibition, modulating the immune cell landscape to limit HIV-1 acquisition and inflammatory environment linked to HIV infection.

T Helper Cells Producing Granulocyte-Macrophage Colony Stimulating Factor as a Risk Marker for Coronary Heart Disease.

Coronary heart disease (CHD) is related to aberrant aggregation of immune cells in the plaques. This study focused on identification of abnormal T cell subtypes and inflammatory factors in CHD patients. To this end, the subtypes of T cells in peripheral blood of CHD patients (n=141) and healthy controls (n=46) were analyzed by flow cytometry. Plasma concentrations of cytokines were analyzed by multiplex assay. It was shown that the number of T helper cells producing granulocyte-macrophage CSF (GM-CSF) was higher in CHD patients in comparison with healthy controls. In addition, the fractions of Th1 and Th17 cells as well as the levels of IL-4, IL-5, IL-6, and IL-10 in CHD patients also surpassed the control values (p<0.05). However, the level of GM-CSF was insignificantly lower in CHD patients. Thus, we revealed a relationship between the number of T cells producing GM-CSF and the severity of CHD. Our results can be used to develop new potential biomarkers for CHD detection.

Psoralen Isolated from the Roots of Dorstenia psilurus Welw. Modulate Th1/Th2 Cytokines and Inflammatory Enzymes in LPS-Stimulated RAW 264.7 Macrophages.

Dorstenia psilurus is a widely used plant spice in traditional African medicine to treat pain-related conditions. However, the anti-inflammatory mechanisms underlying this activity and the main active ingredients of D. psilurus have not yet been fully characterized. This study aimed to isolate and identify the main active anti-inflammatory constituents of the D. psilurus extract and to investigate the underlying anti-inflammatory mechanisms in murine macrophages. Chromatographic techniques and spectroscopic data were used for compound isolation and structure elucidation. The Griess reagent method and the ferrous oxidation-xylenol orange assay were used to evaluate the inhibition of NO production and 15-lipoxygenase activity, respectively. Cyclooxygenase activity was assessed using the fluorometric COX activity assay kit, and Th1/Th2 cytokine measurement was performed using a flow cytometer. The results indicated that the extract and fractions of D. psilurus inhibit NO production and proliferation of RAW 264.7 macrophage cells. Bioguided fractionation led to the identification of psoralen, a furocoumarin, as the main bioactive anti-inflammatory compound. Psoralen inhibited NO production and 15-lipoxygenase activity and reduced pro-inflammatory Th1 cytokines (IFN-γ, TNF-α, and IL-2) while increasing the secretion of anti-inflammatory cytokines (IL-4, IL-6, and IL-10) in activated RAW 264.7 macrophage cells. The encouraging results obtained in this study suggest that psoralen-based multiple modulation strategies could be a useful approach to address the treatment of inflammatory diseases.

Th1 cells reduce the osteoblast-like phenotype in valvular interstitial cells by inhibiting NLRP3 inflammasome activation in macrophages.

BACKGROUND AND AIMS: Inflammation is initiates the propagation phase of aortic valve calcification. The activation of NLRP3 signaling in macrophages plays a crucial role in the progression of calcific aortic valve stenosis (CAVS). IFN-γ regulates NLRP3 activity in macrophages. This study aimed to explore the mechanism of IFN-γ regulation and its impact on CAVS progression and valve interstitial cell transdifferentiation. METHODS AND RESULTS: The number of Th1 cells and the expression of IFN-γ and STAT1 in the aortic valve, spleen and peripheral blood increased significantly as CAVS progressed. To explore the mechanisms underlying the roles of Th1 cells and IFN-γ, we treated CAVS mice with IFN-γ-AAV9 or an anti-IFN-γ neutralizing antibody. While IFN-γ promoted aortic valve calcification and dysfunction, it significantly decreased NLRP3 signaling in splenic macrophages and Ly6C+ monocytes. In vitro coculture showed that Th1 cells inhibited NLPR3 activation in ox-LDL-treated macrophages through the IFN-γR1/IFN-γR2-STAT1 pathway. Compared with untreated medium, conditioned medium from Th1-treated bone marrow-derived macrophages reduced the osteogenic calcification of valvular interstitial cells. CONCLUSION: Inhibition of the NLRP3 inflammasome by Th1 cells protects against valvular interstitial cell calcification as a negative feedback mechanism of adaptive immunity toward innate immunity. This study provides a precision medicine strategy for CAVS based on the targeting of anti-inflammatory mechanisms.

Select amino acids recover cytokine-altered ENaC function in human bronchial epithelial cells.

The airway epithelium plays a pivotal role in regulating mucosal immunity and inflammation. Epithelial barrier function, homeostasis of luminal fluid, and mucociliary clearance are major components of mucosal defense mechanisms. The epithelial sodium channel (ENaC) is one of the key players in controlling airway fluid volume and composition, and characteristic cytokines cause ENaC and barrier dysfunctions following pulmonary infections or allergic reactions. Given the limited understanding of the requisite duration and magnitude of cytokines to affect ENaC and barrier function, available treatment options for restoring normal ENaC activity are limited. Previous studies have demonstrated that distinct amino acids can modulate epithelial ion channel activities and barrier function in intestines and airways. Here, we have investigated the time- and concentration-dependent effect of representative cytokines for Th1- (IFN-γ and TNF-α), Th2- (IL-4 and IL-13), and Treg-mediated (TGF-ß1) immune responses on ENaC activity and barrier function in human bronchial epithelial cells. When cells were exposed to Th1 and Treg cytokines, ENaC activity decreased gradually while barrier function remained largely unaffected. In contrast, Th2 cytokines had an immediate and profound inhibitory effect on ENaC activity that was subsequently followed by epithelial barrier disruption. These functional changes were associated with decreased membrane protein expression of α-, ß-, and γ-ENaC, and decreased mRNA levels of ß- and γ-ENaC. A proprietary blend of amino acids was developed based on their ability to prevent Th2 cytokine-induced ENaC dysfunction. Exposure to the select amino acids reversed the inhibitory effect of IL-13 on ENaC activity by increasing mRNA levels of ß- and γ-ENaC, and protein expression of γ-ENaC. This study indicates the beneficial effect of select amino acids on ENaC activity in an in vitro setting of Th2-mediated inflammation suggesting these amino acids as a novel therapeutic approach for correcting this condition.

[Astragaloside IV reduces renal injury in mice with IgA nephropathy by inhibiting TIM-1 signaling pathway and increasing Th1/Th2 cell ratio].

Objective To investigate the effects of astragaloside IV(AS-IV) on the balance of T helper type 1 (Th1) and Th2 cells in mice with IgA nephropathy (IgAN) and its possible mechanism. Methods The IgAN model of BALB/c mice was established. Successfully modeled mice were randomly divided into four groups: model, AS-IV low dose, AS-IV medium dose and AS-IV high dose groups, with 10 mice in each group. Another 10 mice served as the control group. Mice in the low, medium and high dose groups were administered 12.5, 25 and 50 mg/kg AS-IV suspension (prepared in normal saline) by gavage, while the control and model groups were given an equivalent volume of normal saline. The 24-hour urinary protein (24 h UPr) content and urine red blood cell count were measured in each group. The levels of blood urea nitrogen (BUN), serum creatinine (Scr) and albumin (ALB) were determined. Serum interferon γ (IFN-γ), interleukin 4 (IL-4) and IL-10 levels were detected by ELISA. The ratio of Th1/Th2 cells in peripheral blood of mice was detected using flow cytometry. Histopathological changes in the kidney of mice were observed by HE staining. RT-PCR and Western blot were used to detect the mRNA and protein expressions of T cell immunoglobulin and mucin domain gene 1 (TIM-1), Toll-like receptor 4 (TLR4) in mouse kidney tissue. Results Compared with the model group, in weeks 12 and 15, the urine red blood cell count, 24 h UPr, BUN, Scr, levels of IL-4 and IL-10, the proportion of Th2 cells, as well as the mRNA and protein expression levels of TIM-1 and TLR4 were significantly decreased in the low, medium and high dose groups of AS-IV, and the levels of ALB, IFN-γ, the proportion of Th1 cells and Th1/Th2 cell ratio were increased, with the high-dose group showing the best effects. Conclusion AS-IV can inhibit TIM-1 signaling pathway, increase the Th1/Th2 cell ratio, inhibit the inflammatory reaction, and alleviate the renal injury in IgAN mice.

Tofacitinib Treatment Suppresses CD4+ T-Cell Activation and Th1 Response, Contributing to Protection against Staphylococcal Toxic Shock.

Staphylococcal toxic shock syndrome (STSS) is a rare, yet potentially fatal disease caused by Staphylococcus aureus (S. aureus) enterotoxins, known as superantigens, which trigger an intense immune response. Our previous study demonstrated the protective effect of tofacitinib against murine toxin-induced shock and a beneficial effect against S. aureus sepsis. In the current study, we examined the effects of tofacitinib on T-cell response in peripheral blood using a mouse model of enterotoxin-induced shock. Our data revealed that tofacitinib suppresses the activation of both CD4+ and CD8+ T cells in peripheral blood. Furthermore, both gene and protein levels of Th1 cytokines were downregulated by tofacitinib treatment in mice with enterotoxin-induced shock. Importantly, we demonstrated that CD4+ cells, but not CD8+ cells, are pathogenic in mice with enterotoxin-induced shock. In conclusion, our findings suggest that tofacitinib treatment suppresses CD4+ T-cell activation and Th1 response, thereby aiding in protection against staphylococcal toxic shock in mice. This insight may guide the future development of novel therapies for STSS.

A further examination of growth factors, T helper 1 polarization, and the gut microbiome in major depression: Associations with reoccurrence of illness, cognitive functions, suicidal behaviors, and quality of life.

Growth factors, T helper (Th)1 polarization, and the microbiome are involved in the pathophysiology of major depression (MDD). It remains unclear whether the combination of these three pathways could enhance the accuracy of predicting the features of MDD, including recurrence of illness (ROI), suicidal behaviors and the phenome. We measured serum stem cell factor (SCF), stem cell growth factor (SCGF), stromal cell-derived factor-1 (SDF-1), platelet-derived growth factor (PDGF), hepatocyte growth factor (HGF), macrophage-colony stimulating factor (M-CSF) and vascular endothelial growth factor (VEGF), the ratio of serum Th1/Th2 cytokines (zTh1-zTh2), and the abundances of gut microbiome taxa by analyzing stool samples using 16S rDNA sequencing from 32 MDD patients and 37 healthy controls. The results show that serum SCF is significantly lower and VEGF increased in MDD. Adverse childhood experiences (ACE) and ROI are significantly associated with lowered SCF and increasing VEGF. Lifetime and current suicidal behaviors are strongly predicted (63.5%) by an increased VEGF/SCF ratio, Th1 polarization, a gut microbiome enterotype indicating gut dysbiosis, and lowered abundance of Dorea and Faecalobacterium. Around 80.5% of the variance in the phenome's severity is explained by ROI, ACEs, and lowered Parabacteroides distasonis and Clostridium IV abundances. A large part of the variance in health-related quality of life (54.1%) is explained by the VEGF/SCF ratio, Th1 polarization, ACE, and male sex. In conclusion, key features of MDD are largely predicted by the cumulative effects of ACE, Th1 polarization, aberrations in growth factors and the gut microbiome with increased pathobionts but lowered beneficial symbionts.

Detection of CLCF1 protein expression by flow cytometry.

Cardiotrophin-like cytokine factor 1 (CLCF1) is an IL-6 family cytokine with neurotrophic and immuno-modulating functions. CLCF1 mRNA has been detected in primary and secondary lymphoid organs, and up-regulation of CLCF1 mRNA levels has been associated with the T helper (Th) 17 polarization. However, information regarding CLCF1 expression by immune cells at the protein level remains scarce. We have developed a methodology that uses a monoclonal antibody (mAb) directed against CLCF1 for the detection of human and mouse CLCF1 by flow cytometry. We have successfully detected CLCF1 protein expression in cells from the mouse pro-B cell line Ba/F3 that were transduced with CLCF1 cDNA. Interestingly, we found that the anti-CLCF1 mAb inhibits CLCF1 biological activity in vitro by binding to an epitope that encompasses site III of the cytokine. Moreover, we have detected CLCF1 expression in mouse splenic T cells, as well as in vitro differentiated Th1 cells. The specificity of the fluorescence signal was demonstrated using Clcf1-deficient lymphocytes generated using a conditional knock-out mouse model. The detection of CLCF1 protein by flow cytometry will be a valuable tool to study CLCF1 expression during normal and pathological immune responses.

Plasticity and lineage commitment of individual TH1 cells are determined by stable T-bet expression quantities.

T helper 1 (TH1) cell identity is defined by the expression of the lineage-specifying transcription factor T-bet. Here, we examine the influence of T-bet expression heterogeneity on subset plasticity by leveraging cell sorting of distinct in vivo-differentiated TH1 cells based on their quantitative expression of T-bet and interferon-γ. Heterogeneous T-bet expression states were regulated by virus-induced type I interferons and were stably maintained even after secondary viral infection. Exposed to alternative differentiation signals, the sorted subpopulations exhibited graded levels of plasticity, particularly toward the TH2 lineage: T-bet quantities were inversely correlated with the ability to express the TH2 lineage-specifying transcription factor GATA-3 and TH2 cytokines. Reprogramed TH1 cells acquired graded mixed TH1 + TH2 phenotypes with a hybrid epigenetic landscape. Continuous presence of T-bet in differentiated TH1 cells was essential to ensure TH1 cell stability. Thus, innate cytokine signals regulate TH1 cell plasticity via an individual cell-intrinsic rheostat to enable T cell subset adaptation to subsequent challenges.

Free Fatty Acid 4 Receptor Activation Attenuates Collagen-Induced Arthritis by Rebalancing Th1/Th17 and Treg Cells.

Dietary supplementation with n-3 polyunsaturated fatty acids (PUFA) has been found to be beneficial in rodent rheumatoid arthritis models and human trials. However, the molecular targets of n-3 PUFAs and their beneficial effects on rheumatoid arthritis are under-researched. Free fatty acid receptor 4 (FFA4, also known as GPR120) is a receptor for n-3 PUFA. We aim to investigate whether FFA4 activation reduces collagen-induced rheumatoid arthritis (CIA) by using an FFA4 agonist, compound A (CpdA), in combination with DBA-1J Ffa4 gene wild-type (WT) and Ffa4 gene knock-out (KO) mice. CIA induced an increase in the arthritis score, foot edema, synovial hyperplasia, pannus formation, proteoglycan loss, cartilage damage, and bone erosion, whereas the administration of CpdA significantly suppressed those increases in Ffa4 WT mice but not Ffa4 gene KO mice. CIA increased mRNA expression levels of pro-inflammatory Th1/Th17 cytokines, whereas CpdA significantly suppressed those increases in Ffa4 WT mice but not Ffa4 gene KO mice. CIA induced an imbalance between Th1/Th17 and Treg cells, whereas CpdA rebalanced them in spleens from Ffa4 WT mice but not Ffa4 gene KO mice. In SW982 synovial cells, CpdA reduced the LPS-induced increase in pro-inflammatory cytokine levels. In summary, the present results suggest that the activation of FFA4 in immune and synovial cells could suppress the characteristics of rheumatoid arthritis and be an adjuvant therapy.

Evaluation of cytokine expressions in patients with recurrent aphthous stomatitis: A systematic review and meta-analysis.

This systematic review and meta-analysis aimed to evaluate the expression levels of various T helper (Th) cell-secreted cytokines in recurrent aphthous stomatitis (RAS). Case-control studies comparing the serum or salivary levels of cytokines between RAS patients and healthy controls were searched in PubMed, EMBASE, Web of Science, and Google Scholar prior to September 30, 2023. Cytokines produced by Th1 (interleukin [IL]-1, IL-2, IL-8, IL-12, tumor necrosis factor alpha [TNF-α], interferon gamma [IFN-γ]), Th2 (IL-4, IL-5, IL-6, IL-10, IL-13), and Th17 (IL-17A) cells were investigated. The standard mean difference (SMD) with 95% confidence interval (CI) was calculated to detect the difference. A total of 20 studies comprising 1070 RAS patients and 536 healthy controls were included. RAS patients had significantly higher salivary levels of IL-2 (SMD = 4.15, 95%CI 0.83-7.48), IL-5 (SMD = 0.53, 95%CI 0.05-1.00), IL-6 (SMD = 0.48, 95%CI 0.12-0.84), IL-12 (SMD = 0.94, 95%CI 0.18-1.71), and TNF-α (SMD = 1.31, 95%CI 0.44-2.18) compared to healthy controls. Serum levels of IL-6 (SMD = 0.48, 95%CI 0.30-0.66), TNF-α (SMD = 0.70, 95%CI 0.22-1.17), and IFN-γ (SMD = 0.72, 95%CI 0.17-1.28) were significantly increased, while serum IL-10 levels (SMD = -2.25, 95%CI -3.99 to -0.52) were reduced in RAS patients. Patients diagnosed with major RAS had markedly elevated serum IL-8 levels (SMD = 0.39, 95%CI 0.07-0.71) and a trend toward higher serum IL-6 levels (SMD = 0.51, 95%CI -0.02 to 1.04) than those with minor RAS. In conclusion, Th1/Th2-related cytokines, especially IL-2, IL-6, and TNF-α, are involved in the pathogenesis of RAS development and progression and are potential therapeutic targets for RAS.

IL-2 amplifies quantitative TCR signalling inputs to drive Th1 and Th2 differentiation.

The activation of CD4+ T-cells in a T cell receptor (TCR)-dependent antigen-specific manner is a central characteristic of the adaptive immune response. In addition to ensuring that CD4+ T-cells recognise their cognate antigen during activation, TCR-mediated signalling can also direct the outcome of differentiation. In both in vivo and in vitro model systems, strong TCR signalling has been demonstrated to drive Th1 differentiation, whereas weak TCR signalling drives Th2 responses. During the process of differentiation, TCR signal strength acts as a quantitative component in combination with the qualitative effects imparted by cytokines to polarise distinct T-helper lineages. Here, we investigated the role of interleukin 2 (IL-2) signalling in determining the outcome of TCR-dependent differentiation. IL-2 production was initiated as an early response to TCR-induced activation and was regulated by the strength of TCR signalling initially received. In the absence of IL-2, TCR dependent differentiation was found to be abolished. However, proliferative responses and early markers of activation were maintained, including the upregulation of GATA3, Tbet and Foxp3 at 24 h post-stimulation. Demonstrating that IL-2 signalling has a key role in stabilising and amplifying lineage-specific transcirption factor expression during differentiation. Further, activation of IL-2-deficient T-cells in the presence of exogenous cytokines was sufficient to restore differentiation whilst maintaining transcriptional signatures imparted during initial TCR signalling. Combined, our data demonstrate that the integration of quantitative TCR-dependent signalling and qualitative IL-2 signalling is essential for determining the fate of CD4+ T-cells during differentiation.

PDIA3 orchestrates effector T cell program by serving as a chaperone to facilitate the non-canonical nuclear import of STAT1 and PKM2.

Dysregulated T cell activation underpins the immunopathology of rheumatoid arthritis (RA), yet the machineries that orchestrate T cell effector program remain incompletely understood. Herein, we leveraged bulk and single-cell RNA sequencing data from RA patients and validated protein disulfide isomerase family A member 3 (PDIA3) as a potential therapeutic target. PDIA3 is remarkably upregulated in pathogenic CD4 T cells derived from RA patients and positively correlates with C-reactive protein level and disease activity score 28. Pharmacological inhibition or genetic ablation of PDIA3 alleviates RA-associated articular pathology and autoimmune responses. Mechanistically, T cell receptor signaling triggers intracellular calcium flux to activate NFAT1, a process that is further potentiated by Wnt5a under RA settings. Activated NFAT1 then directly binds to the Pdia3 promoter to enhance the expression of PDIA3, which complexes with STAT1 or PKM2 to facilitate their nuclear import for transcribing T helper 1 (Th1) and Th17 lineage-related genes, respectively. This non-canonical regulatory mechanism likely occurs under pathological conditions, as PDIA3 could only be highly induced following aberrant external stimuli. Together, our data support that targeting PDIA3 is a vital strategy to mitigate autoimmune diseases, such as RA, in clinical settings.

Low-level LASER therapy accelerates fungal lesions cicatrization by increasing the production of Th1 and Th2 cytokines.

Paracoccidioidomycosis (PCM) is a systemic mycosis with serious clinical consequences in which the use of antifungal drugs requires long-term treatment. Therefore, we studied the effect of low-level LASER therapy (LLLT) to evaluate its prospects as a complementary treatment for PCM and improve the clinical response to the disease. OBJECTIVES: Our study focused on the resolution of lesions caused by fungal infection using a subcutaneous air pouch model of infection. METHODS: We evaluated cell profile and cytokines, fungi viability, and the presence of fibroblasts and fibrocytes at the site of infection. Inoculation of P. brasiliensis (Pb) was performed using a subcutaneous air pouch model and the LLLT irradiation was performed on alternate days on the rear paws of mice for 10 days, after which the cells from the air pouch were collected and analyzed. RESULTS: In animals irradiated with LLLT, the influx of cells to the air pouch was reduced, but they were more activated and produced pro-inflammatory (IL-12, IL-17 and TNF-α) and neutrophil (PMN) activating cytokines (IL-8, GM-CSF and γ-IFN). A better resolution of the infection, evidenced by the reduction in the number of viable fungi with preserved morphology in the air pouch, and an increase in the number of fibrocytes, indicating a healing profile were also observed. CONCLUSION: LLLT decreased the influx of PMN, but those presents were highly activated, with increased fungicidal activity. LLLT irradiation also resulted in earlier cicatrization at the site of infection, leading to a better outcome of the infection. These data are favorable to the use of LLLT as a complementary therapy in PCM.

Senotherapeutic Peptide 14 Suppresses Th1 and M1 Human T Cell and Monocyte Subsets In Vitro.

Inflammation contributes to the onset and exacerbation of numerous age-related diseases, often manifesting as a chronic condition during aging. Given that cellular senescence fosters local and systemic inflammation, senotherapeutic interventions could potentially aid in managing or even reducing inflammation. Here, we investigated the immunomodulatory effects of the senotherapeutic Peptide 14 (Pep 14) in human peripheral blood mononuclear cells (PBMCs), monocytes, and macrophages. We found that, despite failing to significantly influence T cell activation and proliferation, the peptide promoted a Th2/Treg gene expression and cytokine signature in PBMCs, characterized by increased expression of the transcription factors GATA3 and FOXP3, as well as the cytokines IL-4 and IL-10. These observations were partially confirmed through ELISA, in which we observed increased IL-10 release by resting and PHA-stimulated PBMCs. In monocytes from the U-937 cell line, Pep 14 induced apoptosis in lipopolysaccharide (LPS)-stimulated cells and upregulated IL-10 expression. Furthermore, Pep 14 prevented LPS-induced activation and promoted an M2-like polarization in U-937-derived macrophages, evidenced by decreased expression of M1 markers and increased expression of M2 markers. We also showed that the conditioned media from Pep 14-treated macrophages enhanced fibroblast migration, indicative of a functional M2 phenotype. Taken together, our findings suggest that Pep 14 modulates immune cell function towards an anti-inflammatory and regenerative phenotype, highlighting its potential as a therapeutic intervention to alleviate immunosenescence-associated dysregulation.

Zinc Ionophore Pyrithione Mimics CD28 Costimulatory Signal in CD3 Activated T Cells.

Zinc is an essential trace element that plays a crucial role in T cell immunity. During T cell activation, zinc is not only structurally important, but zinc signals can also act as a second messenger. This research investigates zinc signals in T cell activation and their function in T helper cell 1 differentiation. For this purpose, peripheral blood mononuclear cells were activated via the T cell receptor-CD3 complex, and via CD28 as a costimulatory signal. Fast and long-term changes in intracellular zinc and calcium were monitored by flow cytometry. Further, interferon (IFN)-γ was analyzed to investigate the differentiation into T helper 1 cells. We show that fast zinc fluxes are induced via CD3. Also, the intracellular zinc concentration dramatically increases 72 h after anti-CD3 and anti-CD28 stimulation, which goes along with the high release of IFN-γ. Interestingly, we found that zinc signals can function as a costimulatory signal for T helper cell 1 differentiation when T cells are activated only via CD3. These results demonstrate the importance of zinc signaling alongside calcium signaling in T cell differentiation.

miR-224-5p Attenuates Allergic Responses in Mice with Allergic Rhinitis by Modulating the Th1/Th2 Response.

Background: Allergic rhinitis (AR) is a common chronic respiratory disease that has become a global health problem. miRNAs play an important role in multiple immune and inflammatory diseases, including AR. In this work, the mechanism by which miR-224-5p regulates AR in vivo and in vitro was examined. Methods: Human nasal epithelial cells (HNEpCs) were used to establish an AR cell model induced by Der P1, and C57BL/6 mice were used to establish an AR animal model induced by OVA (ovalbumin). RT-qPCR was used to determine the level of miR-224-5p; western blot analysis was used to determine GATA3; ELISA was used to determine the levels of OVA-specific IgE, IFN-γ, IL-4, IL-5, and IL-13; flow cytometry was used to determine the differentiation of Th1 and Th2 cells; and HE and PAS staining was used to observe the histopathological alterations in the mouse nasal mucosa and spleen. Results: miR-224-5p was downregulated in nasal mucosa from mice with AR and an AR cell model. Overexpressed miR-224-5p can improve AR development and attenuate AR symptoms by regulating GATA3-mediated Th1/Th2 responses. Conclusion: miR-224-5p attenuates allergic reactions in mice with AR by regulating the Th1/Th2 response.

Trichloroethylene metabolite modulates DNA methylation-dependent gene expression in Th1-polarized CD4+ T cells from autoimmune-prone mice.

Trichloroethylene (TCE) is an industrial solvent and widespread environmental contaminant associated with CD4+ T-cell activation and autoimmune disease. Prior studies showed that exposure to TCE in the drinking water of autoimmune-prone mice expanded effector/memory CD4+ T cells with an interferon-γ (IFN-γ)-secreting Th1-like phenotype. However, very little is known how TCE exposure skews CD4+ T cells towards this pro-inflammatory Th1 subset. As observed previously, TCE exposure was associated with hypermethylation of regions of the genome related to transcriptional repression in purified effector/memory CD4 T cells. We hypothesized that TCE modulates transcriptional and/or epigenetic programming of CD4+ T cells as they differentiate from a naive to effector phenotype. In the current study, purified naive CD4 T cells from both male and female autoimmune-prone MRL/MpJ mice were activated ex vivo and polarized towards a Th1 subset for 4 days in the presence or absence of the oxidative metabolite of TCE, trichloroacetaldehyde hydrate (TCAH) in vitro. An RNA-seq assessment and reduced representation bisulfite sequencing for DNA methylation were conducted on Th1 cells or activated, non-polarized cells. The results demonstrated TCAH's ability to regulate key genes involved in the immune response and autoimmunity, including Ifng, by altering the level of DNA methylation at the gene promoter. Intriguing sex differences were observed and for the most part, the effects were more robust in females compared to males. In conclusion, TCE via TCAH epigenetically regulates gene expression in CD4+ T cells. These results may have implications for mechanistic understanding or future therapeutics for autoimmunity.

P2X7 receptor antagonists modulate experimental autoimmune neuritis via regulation of NLRP3 inflammasome activation and Th17 and Th1 cell differentiation.

BACKGROUND: Guillain-Barré syndrome (GBS), a post-infectious, immune-mediated, acute demyelinating disease of the peripheral nerves and nerve roots, represents the most prevalent and severe acute paralyzing neuropathy. Purinergic P2X7 receptors (P2X7R) play a crucial role in central nervous system inflammation. However, little is known about their role in the immune-inflammatory response within the peripheral nervous system. METHODS: Initially, we assessed the expression of purinergic P2X7R in the peripheral blood of patients with GBS using flow cytometry and qRT-PCR. Next, we explored the expression of P2 X7R in CD4+ T cells, CD8+ T cells, and macrophages within the sciatic nerves and spleens of rats using immunofluorescence labeling and flow cytometry. The P2X7R antagonist brilliant blue G (BBG) was employed to examine its therapeutic impact on rats with experimental autoimmune neuritis (EAN) induced by immunization with the P0180 - 199 peptide. We analyzed CD4+ T cell differentiation in splenic mononuclear cells using flow cytometry, assessed Th17 cell differentiation in the sciatic nerve through immunofluorescence staining, and examined the expression of pro-inflammatory cytokine mRNA using RT-PCR. Additionally, we performed protein blotting to assess the expression of P2X7R and NLRP3-related inflammatory proteins within the sciatic nerve. Lastly, we utilized flow cytometry and immunofluorescence labeling to examine the expression of NLRP3 on CD4+ T cells in rats with EAN. RESULTS: P2X7R expression was elevated not only in the peripheral blood of patients with GBS but also in rats with EAN. In rats with EAN, inhibiting P2X7R with BBG alleviated neurological symptoms, reduced demyelination, decreased inflammatory cell infiltration of the peripheral nerves, and improved nerve conduction. BBG also limited the production of pro-inflammatory molecules, down-regulated the expression of P2X7R and NLRP3, and suppressed the differentiation of Th1 and Th17 cells, thus protecting against EAN. These effects collectively contribute to modifying the inflammatory environment and enhancing outcomes in EAN rats. CONCLUSIONS: Suppression of P2X7R relieved EAN manifestation by regulating CD4+ T cell differentiation and NLRP3 inflammasome activation. This finding underscores the potential significance of P2X7R as a target for anti-inflammatory treatments, advancing research and management of GBS.