The T(reg)/Th17 cell balance: a new paradigm for autoimmunity

Galectin-3 absence alters lymphocytes populations dynamics behavior and promotes functional recovery after spinal cord injury in mice

Spinal cord injury (SCI) results from various mechanisms that damage the nervous tissue and the blood-brain barrier, leading to sensory and motor function loss below the injury site. Unfortunately, current therapeutic approaches for SCI have limited efficacy in improving patients outcomes. Galectin-3, a protein whose expression increases after SCI, influences the neuroinflammatory response by favoring pro-inflammatory M1 macrophages and microglia, while inhibiting pro-regenerative M2 macrophages and microglia, which are crucial for inflammation resolution and tissue regeneration. Previous studies with Galectin-3 knock-out mice demonstrated enhanced motor recovery after SCI. The M1/M2 balance is strongly influenced by the predominant lymphocytic profiles (Th1, Th2, T Reg, Th17) and cytokines and chemokines released at the lesion site. The present study aimed to investigate how the absence of galectin-3 impacts the adaptive immune system cell population dynamics in various lymphoid spaces following a low thoracic spinal cord compression injury (T9-T10) using a 30 g vascular clip for one minute. It also aimed to assess its influence on the functional outcome in wild-type (WT)and Galectin-3 knock-out (GALNEG) mice. Histological analysis with hematoxylin-eosin and Luxol Fast Blue staining revealed that WT and GALNEG animals exhibit similar spinal cord morphology. The absence of galectin-3 does not affect the common neuroanatomy shared between the groups prompting us to analyze outcomes between both groups. Following our crush model, both groups lost motor and sensory functions below the lesion level. During a 42-day period, GALNEG mice demonstrated superior locomotor recovery in the Basso Mouse Scale (BMS) gait analysis and enhanced motor coordination performance in the ladder rung walk test (LRW) compared to WT mice. GALNEG mice also exhibited better sensory recovery, and their electrophysiological parameters suggested a higher number of functional axons with faster nerve conduction. Seven days after injury, flow cytometry of thymus, spleen, and blood revealed an increased number of T Reg and Th2 cells, accompanied by a decrease in Th1 and Th17 cells in GALNEG mice. Immunohistochemistry conducted on the same day exhibited an increased number of Th2 and T Reg cells around the GALNEG's spinal cord lesion site. At 42-day dpi immunohistochemistry analyses displayed reduced astrogliosis and greater axon preservation in GALNEG's spinal cord seem as a reduction of GFAP immunostaining and an increase in NFH immunostaining, respectively. In conclusion, GALNEG mice exhibited better functional recovery attributed to the milder pro-inflammatory influence, compensated by a higher quantity of T Reg and Th2 cells. These findings suggest that galectin-3 plays a crucial role in the immune response after spinal cord injury and could be a potential target for clinical therapeutic interventions.

Analysis of Th17 cell population and expression of microRNA and factors related to Th17 in patients with premature ovarian failure

Folliculogenesis is the process where follicles in the ovaries develop and eventually lead to ovulation. Any disruption to this process can cause premature ovarian failure. miR-326 is one of the microRNAs whose expression leads to Th17 production. Th17 activates the immune system to respond more vigorously, and by producing interlukins and cytokines causes inflammation and autoimmune disorders. Th17-induced inflammation and Th17/Treg imbalance can result in POF. This investigation took samples from 30 POF patients and 30 healthy people. The study utilized PCR to assess the expression levels of cytokines, specific transcription factor (ROR-γt), and miR-326. Additionally, ELISA was employed to analyze serum levels of IL-17, IL-21, IL-23. Furthermore, flow cytometry was utilized to determine the frequency of Th17. Compared to the control group, our results demonstrated a rise in the transcription factor RORɣt and a considerable rise in the frequency of Th17 cells in patients with POF. The level of inflammatory cytokines IL-17, IL-21, and IL-23 secreted in serum samples of patients with POF increased significantly compared to the control group. Results of investigating microRNA associated with Th17 cells also showed increased expression of miR-326 in females suffering from POF. The elevation of pro-inflammatory markers in women with POF contrary to the control group underscores the significant involvement of the immune system in pregnancy disorders pathogenesis. Consequently, immunological factors may serve as promising biomarkers for predicting POF likelihood in high-risk women in the future.

Core fucosylation of maternal milk N-glycans imparts early-life immune tolerance through gut microbiota-dependent regulation in RORγt+ Treg cells

Milk glycans play key roles in shaping and maintaining a healthy infant gut microbiota. Core fucosylation catalyzed by fucosyltransferase (Fut8) is the major glycosylation pattern on human milk N-glycan, which was crucial for promoting the colonization and dominant growth of Bifidobacterium and Lactobacillus spp. in neonates. However, the influence of core-fucose in breast milk on the establishment of early-life immune tolerance remains poorly characterized. In this study, we found that the deficiency of core-fucose in the milk of maternal mice caused by Fut8 gene heterozygosity (Fut8+/-) resulted in poor immune tolerance towards the ovalbumin (OVA) challenge, accompanied by a reduced proportion of intestinal RORγt+ Treg cells and the abundance of Lactobacillus spp., especially L. reuteri and L. johnsonii, in their breast-fed neonates. The administration of the L. reuteri and L. johnsonii mixture to neonatal mice compromised the OVA-induced allergy and up-regulated the intestinal RORγt+ Treg cell proportions. However, Lactobacillus mixture supplementation did not alleviate allergic responses in RORγt+ Treg cell-deficient mice caused by Rorc gene heterozygosity (Rorc+/-) post OVA challenge, indicating that the intervention effects depend on the RORγt+ Treg cells. Interestingly, instead of L. reuteri and L. johnsonii, we found that the relative abundance of another Lactobacillus spp., L. murinus, in the gut of the offspring mice was significantly promoted by intervention, which showed enhancing effects on the proliferation of splenic and intestinal RORγt+ Treg cells in in vitro studies. The above results indicate that core fucosylation of breast milk N-glycans is beneficial for the establishment of RORγt+ Treg cell mediated early-life immune tolerance through the manipulation of symbiotic bacteria in mice.

Deciphering the relationship between temperature and immunity

Fever is a hallmark symptom of disease across the animal kingdom. Yet, despite the evidence linking temperature fluctuation and immune response, much remains to be discovered about the molecular mechanisms governing these interactions. In patients with rheumatoid arthritis, for instance, it is clinically accepted that joint temperature can predict disease progression. But it was only recently demonstrated that the mitochondria of stimulated T cells can rise to an extreme 50°C, potentially indicating a cellular source of these localized 'fevers'. A challenge to dissecting these mechanisms is a bidirectional interplay between temperature and immunity. Heat shock response is found in virtually all organisms, activating protective pathways when cells are exposed to elevated temperatures. However, the temperature threshold that activates these pathways can vary within the same organism, with human immune cells, in particular, demonstrating differential sensitivity to heat. Such inter-cellular variation may be clinically relevant given the small but significant temperature differences seen between tissues, ages, and sexes. Greater understanding of how such small temperature perturbations mediate immune responses may provide new explanations for persistent questions in disease such as sex disparity in disease prevalence. Notably, the prevalence and severity of many maladies are rising with climate change, suggesting temperature fluctuations can interact with disease on multiple levels. As global temperatures are rising, and our body temperatures are falling, questions regarding temperature-immune interactions are increasingly critical. Here, we review this aspect of environmental interplay to better understand temperature's role in immune variation and subsequent risk of disease.

Identification of unstable regulatory and autoreactive effector T cells that are expanded in patients with FOXP3 mutations

Studies of the monogenic autoimmune disease immunodysregulation polyendocrinopathy enteropathy X-linked syndrome (IPEX) have elucidated the essential function of the transcription factor FOXP3 and thymic-derived regulatory T cells (Tregs) in controlling peripheral tolerance. However, the presence and the source of autoreactive T cells in IPEX remain undetermined. Here, we investigated how FOXP3 deficiency affects the T cell receptor (TCR) repertoire and Treg stability in vivo and compared T cell abnormalities in patients with IPEX with those in patients with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy syndrome (APECED). To study Tregs independently of their phenotype and to analyze T cell autoreactivity, we combined Treg-specific demethylation region analyses, single-cell multiomic profiling, and bulk TCR sequencing. We found that patients with IPEX, unlike patients with APECED, have expanded autoreactive T cells originating from both autoreactive effector T cells (Teffs) and Tregs. In addition, a fraction of the expanded Tregs from patients with IPEX lost their phenotypic and functional markers, including CD25 and FOXP3. Functional experiments with CRISPR-Cas9-mediated FOXP3 knockout Tregs and Tregs from patients with IPEX indicated that the patients' Tregs gain a TH2-skewed Teff-like function, which is consistent with immune dysregulation observed in these patients. Analyses of FOXP3 mutation-carrier mothers and a patient with IPEX after hematopoietic stem cell transplantation indicated that Tregs expressing nonmutated FOXP3 prevent the accumulation of autoreactive Teffs and unstable Tregs. These findings could be directly used for diagnostic and prognostic purposes and for monitoring the effects of immunomodulatory treatments.

Protective role of IL-17-producing γδ T cells in a laser-induced choroidal neovascularization mouse model

BACKGROUND

Vision loss in patients with wet/exudative age-related macular degeneration (AMD) is associated with choroidal neovascularization (CNV), and AMD is the leading cause of irreversible vision impairment in older adults. Interleukin-17A (IL-17A) is a component of the microenvironment associated with some autoimmune diseases. Previous studies have indicated that wet AMD patients have elevated serum IL-17A levels. However, the effect of IL-17A on AMD progression needs to be better understood. We aimed to investigate the role of IL-17A in a laser-induced CNV mouse model.

METHODS

We established a laser-induced CNV mouse model in wild-type (WT) and IL-17A-deficient mice and then evaluated the disease severity of these mice by using fluorescence angiography. We performed enzyme-linked immunosorbent assay (ELISA) and fluorescence-activated cell sorting (FACS) to analyze the levels of IL-17A and to investigate the immune cell populations in the eyes of WT and IL-17A-deficient mice. We used ARPE-19 cells to clarify the effect of IL-17A under oxidative stress.

RESULTS

In the laser-induced CNV model, the CNV lesions were larger in IL-17A-deficient mice than in WT mice. The numbers of γδ T cells, CD3+CD4+RORγt+ T cells, Treg cells, and neutrophils were decreased and the number of macrophages was increased in the eyes of IL-17A-deficient mice compared with WT mice. In WT mice, IL-17A-producing γδ T-cell numbers increased in a time-dependent manner from day 7 to 28 after laser injury. IL-6 levels increased and IL-10, IL-24, IL-17F, and GM-CSF levels decreased in the eyes of IL-17A-deficient mice after laser injury. In vitro, IL-17A inhibited apoptosis and induced the expression of the antioxidant protein HO-1 in ARPE-19 cells under oxidative stress conditions. IL-17A facilitated the repair of oxidative stress-induced barrier dysfunction in ARPE-19 cells.

CONCLUSIONS

Our findings provide new insight into the protective effect of IL-17A in a laser-induced CNV model and reveal a novel regulatory role of IL-17A-producing γδ T cells in the ocular microenvironment in wet AMD.

IL-17 A correlates with disease progression in papillary thyroid carcinoma

BACKGROUND

Cancer progression can be promoted by chronic inflammation. Local immune response may be associated with favourable or unfavourable prognosis of Papillary Thyroid Carcinoma (PTC). Regulatory T (Treg) cells and T helper 17 (Th17) cells exert opposing function and their balance may have a vital role in promotion of tumor growth. Treg cells in tumor microenvironment (TME) may promote tumor progression and reduced survival of patients. Whereas, Th17 cells can promote or inhibit tumor progression depending on phenotypic characteristics of tumor. In this study, we aimed to analyse the kind of immune response developed and its prognostic impact in future therapeutics.

METHODS

Cytometric Bead Array (CBA) analysis of pro and anti-inflammatory cytokines (IFN-gamma, IL-2, IL-6, IL-17 A, TNF-alpha and IL-4, IL-10) was done in 15 PTC irrespective of Lymphocytic Thyroiditis (LT) and 16 Hashimoto's Thyroiditis (HT) cases. Immunohistochemical expression of FoxP3 and IL-17 A was studied in 27 cases of PTC with LT. Whereas, quantitative gene expression of both was analysed in 10 cases.

RESULTS

All the pro-inflammatory cytokines showed mild elevation in PTC with LT. On IHC, IL-17 A expression was observed in 74% PTC with LT. Whereas, FoxP3 was present in only 40% cases. Also, IL-17 A expression was significantly associated with age group (> 45 years), tumor size ≤ 1 cm and disease progression.

CONCLUSIONS

Increased expression of cytokines suggested correlation between inflammatory factors and progression of thyroid tumors. Along with this, the balance between IL-17 A and FoxP3 may play an important role in PTC development, prognosis and future management.

UV radiation and air pollution as drivers of major autoimmune conditions

Autoimmune diseases comprise a very heterogeneous group of disorders characterized by disruptive immune responses against self-antigens, chronic morbidity and increased mortality. The incidence and prevalence of major autoimmune conditions are particularly high in the western world, at northern latitudes, and in industrialized countries. This study will mainly focus on five major autoimmune conditions, namely type 1 diabetes, multiple sclerosis, inflammatory bowel diseases, rheumatoid arthritis, and autoimmune thyroid disorders. Epidemiological and experimental evidence suggests a protective role of sunlight exposure on the etiology of major autoimmune conditions mediated by the endogenous production of vitamin D and nitric oxide. A historical perspective shows how the rise of anthropogenic air pollutants is temporally associated with dramatic increases in incidence of these conditions. The scattering caused by ambient particulate matter and the presence of tropospheric ozone can reduce the endogenous production of vitamin D and nitric oxide, which are implicated in maintaining the immune homeostasis. Air pollutants have direct detrimental effects on the human body and are deemed responsible of an increasingly higher portion of the annual burden of human morbidity and mortality. Air pollution contributes in systemic inflammation, activates oxidative pathways, induces epigenetic alterations, and modulates the function and phenotype of dendritic cells, Tregs, and T-cells. In this review, we provide epidemiological and mechanistic insights regarding the role of UV-mediated effects in immunity and how anthropic-derived air pollution may affect major autoimmune conditions through direct and indirect mechanisms.

OMIP-090: A 20-parameter flow cytometry panel for rapid analysis of cell diversity and homing capacity in human conventional and regulatory T cells

The panel was developed and optimized for monitoring changes in homing capacity and functional diversity of human CD4+ conventional and regulatory T cell subsets. The analysis was based on expression of only surface markers in freshly isolated peripheral blood mononuclear cells (PBMCs) to reduce at minimum any alteration due to permeabilization or freezing/thawing procedures. We included markers to assess the distribution of naïve and memory populations based on the expression of CD45RA, CCR7, CD25, CD28 and CD95 in both conventional and regulatory T cells. The identification of major functional subsets was performed using CCR4, CCR6, CCR10, CXCR3 and CXCR5. Homing capacity of these subsets to skin, airway tract, gut and inflammatory lesions could finally be assessed with the markers CLA, CCR3, CCR5 and integrin β7. The panel was tested on freshly isolated PBMCs from healthy donors and patients with allergic rhinitis or autoimmune disorders.

Recent Progress in Multiple Sclerosis Treatment Using Immune Cells as Targets

Multiple sclerosis (MS) is an autoimmune-mediated demyelinating disease of the central nervous system. The main pathological features are inflammatory reaction, demyelination, axonal disintegration, reactive gliosis, etc. The etiology and pathogenesis of the disease have not been clarified. The initial studies believed that T cell-mediated cellular immunity is the key to the pathogenesis of MS. In recent years, more and more evidence has shown that B cells and their mediated humoral immune and innate immune cells (such as microglia, dendritic cells, macrophages, etc.) also play an important role in the pathogenesis of MS. This article mainly reviews the research progress of MS by targeting different immune cells and analyzes the action pathways of drugs. The types and mechanisms of immune cells related to the pathogenesis are introduced in detail, and the mechanisms of drugs targeting different immune cells are discussed in depth. This article aims to clarify the pathogenesis and immunotherapy pathway of MS, hoping to find new targets and strategies for the development of therapeutic drugs for MS.

Tumor microenvironment-mediated immune evasion in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and is the third leading cause of tumor-related mortality worldwide. In recent years, the emergency of immune checkpoint inhibitor (ICI) has revolutionized the management of HCC. Especially, the combination of atezolizumab (anti-PD1) and bevacizumab (anti-VEGF) has been approved by the FDA as the first-line treatment for advanced HCC. Despite great breakthrough in systemic therapy, HCC continues to portend a poor prognosis owing to drug resistance and frequent recurrence. The tumor microenvironment (TME) of HCC is a complex and structured mixture characterized by abnormal angiogenesis, chronic inflammation, and dysregulated extracellular matrix (ECM) remodeling, collectively contributing to the immunosuppressive milieu that in turn prompts HCC proliferation, invasion, and metastasis. The tumor microenvironment coexists and interacts with various immune cells to maintain the development of HCC. It is widely accepted that a dysfunctional tumor-immune ecosystem can lead to the failure of immune surveillance. The immunosuppressive TME is an external cause for immune evasion in HCC consisting of 1) immunosuppressive cells; 2) co-inhibitory signals; 3) soluble cytokines and signaling cascades; 4) metabolically hostile tumor microenvironment; 5) the gut microbiota that affects the immune microenvironment. Importantly, the effectiveness of immunotherapy largely depends on the tumor immune microenvironment (TIME). Also, the gut microbiota and metabolism profoundly affect the immune microenvironment. Understanding how TME affects HCC development and progression will contribute to better preventing HCC-specific immune evasion and overcoming resistance to already developed therapies. In this review, we mainly introduce immune evasion of HCC underlying the role of immune microenvironment, describe the dynamic interaction of immune microenvironment with dysfunctional metabolism and the gut microbiome, and propose therapeutic strategies to manipulate the TME in favor of more effective immunotherapy.

Peripheral blood cytokines as potential diagnostic biomarkers of suicidal ideation in patients with first-episode drug-naïve major depressive disorder

Objective

Major Depressive Disorder (MDD) is a leading cause of disability, with a high risk of suicidal ideation (SI). Few studies have evaluated the potential of multiple cytokines as biomarkers for SI in patients with MDD. In the present study, we examined the serum levels of multiple cytokines in patients with first-episode drug-naïve MDD, with the aim to discover and identify serum cytokines-based biomarkers for identification of SI in MDD.

Methods

A total of 55 patients with first-episode drug-naïve MDD were enrolled and divided into two groups: 26 MDD patients without SI and 29 MDD patients with SI. Beck Scale for Suicide Ideation was used to estimate SI. A total of 37 cytokines were measured using Multiplex Luminex Assays. The levels of serum cytokines between MDD patients without SI and MDD patients with SI were compared and diagnostic values of different cytokines were evaluated using the receiver operating characteristic (ROC) curve method for discriminating MDD patients with SI from MDD patients without SI. The relationship between the group and the abnormal cytokines were investigated in multiple linear regression models, with adjustments for age, gender, BMI, smoking, and Hamilton Depression Rating Scale-24 (HAMD-24) scores.

Results

The levels of CCL26 and VEGF in MDD patients with SI were significantly lower than those in MDD patients without SI (all P < 0.05). On the contrary, the levels of IL-17C, CXCL10, and TNF-β in MDD patients with SI were significantly higher than those in MDD patients without SI (all P < 0.05). Moreover, the results of multiple linear regression revealed that group was a significant independent predictor of serum IL-17C, CCL-26, VEGF, and TNF-β levels (all P < 0.05). In terms of CXC10, group was also likely to be a significant independent predictor (β = 0.257, P = 0.063). Furthermore, the AUC values of IL-17C and TNF-β were 0.728 and 0.732, respectively. Additionally, a combined panel of IL-17C and TNF-β achieved a high accuracy in discriminating MDD patients with SI from MDD patients without SI (AUC = 0.848, sensitivity = 75.9%, specificity = 72.7%).

Conclusions

These results suggested that circulating IL-17C and TNF-β may hold promise in the discovery of biomarkers for identification of SI in MDD.

A Snapshot of T Cell Subset Cytokines in Pemphigus Vulgaris: A Cross-Sectional Study

Objective: The purpose of this study was to assess the serum levels of cytokines produced by the Th1 (IFN‐γ, IL-12), Th2 (IL‐4), Th17 (IL-6, IL‐17A, IL‐23), and Treg (IL‐10 and TGF-β) pathways in individuals with active pemphigus vulgaris (PV) and to determine whether these levels were correlated with the severity of the disease condition.

Patients and methods: This study was conducted with 90 individuals, of which 50 were PV patients and 40 healthy individuals (age and gender-matched) as controls. Serum samples were collected and tested for cytokine levels by ELISA (enzyme-linked immunosorbent assay). The cytokine levels in the serum of PV patients and healthy controls were compared statistically using the Mann-Whitney test for nonparametric samples. The strength of the association between the variables was evaluated using the Spearman correlation test.

Results: The mean serum levels of IFN- γ (p < 0.001), IL-6 (p < 0.001), IL-10 (p < 0.001), IL-12 (p < 0.05), and IL-17 (p < 0.001) were significantly higher and TGF-β were significantly low in the PV patients than those observed in the control group. The mean concentration of serum IL-4 in patients with PV did not differ from those in the control group.

Conclusions: In active PV, the Th1 and Th17 pathways are involved in the development and progression of the disease, whereas the Th2 pathway is blocked. Both of these pathways play a significant role in the disease. It is possible that the Treg pathway acts as an antagonist to the Th1 and Th17 pathways, which would cause the disease to become more localised. This study lays the foundation for a better understanding of the aetiology of PV and implies that cytokines could be used as potential therapeutic targets and disease activity biomarkers.

Mechanisms of Primary and Acquired Resistance to Immune Checkpoint Inhibitors in Patients with Hepatocellular Carcinoma

Simple Summary

Immune checkpoint inhibitors (ICIs) are now a cornerstone of systemic treatment for hepatocellular carcinoma (HCC). However, their efficacy is blunted by mechanisms of tumour resistance in many patients. This review reports on the state of the art of resistance to ICIs, focusing on HCC, with the aim to provide clear and direct information to clinicians and researchers. Growing knowledge on the mechanisms of resistance to immunotherapy can indeed guide the choice of and expand the application of novel combined treatments.

Abstract

Hepatocellular carcinoma (HCC) is the most common liver cancer and a relevant global health problem. Immune checkpoint inhibitors (ICIs) represent the most effective systemic treatment for HCC. However, due to primary resistance, approximately 40% of HCC patients do not achieve a disease control with ICIs. Moreover, a similar proportion will experience disease progression after an initial response caused by secondary resistance. This review describes the mechanisms of primary and secondary resistance and reports the ongoing therapeutic strategies to overcome these obstacles.

Nanoparticle-Based Therapeutics to Overcome Obstacles in the Tumor Microenvironment of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is still a main health concern around the world, with a rising incidence and high mortality rate. The tumor-promoting components of the tumor microenvironment (TME) play a vital role in the development and metastasis of HCC. TME-targeted therapies have recently drawn increasing interest in the treatment of HCC. However, the short medication retention time in TME limits the efficiency of TME modulating strategies. The nanoparticles can be elaborately designed as needed to specifically target the tumor-promoting components in TME. In this regard, the use of nanomedicine to modulate TME components by delivering drugs with protection and prolonged circulation time in a spatiotemporal manner has shown promising potential. In this review, we briefly introduce the obstacles of TME and highlight the updated information on nanoparticles that modulate these obstacles. Furthermore, the present challenges and future prospects of TME modulating nanomedicines will be briefly discussed.

Fucose as a potential therapeutic molecule against the immune-mediated inflammation in IgA nepharopathy: An unrevealed link

Background

IgA nephropathy (IgAN) is an autoimmune disease that affects people of any age and is an important cause of end-stage renal disease. However, the pathogenesis and pathophysiology of IgAN is not clear. This article aimed to explore the immune-mediated inflammation and genetic mechanisms in IgAN.

Methods

The transcriptome sequencing data of IgAN glomeruli in the Gene Expression Omnibus database were downloaded. Single-sample gene set enrichment analysis was used to estimate the immune microenvironment of the merged microarray data and GSE141295. IgAN samples were divided into two clusters by cluster analysis. “limma” and “DEseq2” package in R were used to identify differentially expressed genes (DEGs). The weighted gene co-expression network analysis (WGCNA) was used to identify the co-expression modules related to inflammation in IgAN. R software package “clusterProfiler” was used for enrichment analysis, whereas Short Time-Series Expression Miner (STEM) analysis was used to identify the trend of gene expression. Machine-learn (ML) was performed using the shiny app. Finally, Drug Signatures Database (DSigDB) was used to identify potential molecules for treating IgAN.

Results

The infiltration of macrophages in IgAN glomeruli was increased, whereas CD4+ T cells, especially inducedregulatory T cells (iTregs) were decreased. A total of 1,104 common DEGs were identified from the merged data and GSE141295. Brown module was identified to have the highest inflammatory correlation with IgAN using WGCNA, and 15 hub genes were screened from this module. Among these 15 hub genes, 14 increased with the severity of IgAN inflammation based on STEM analysis. Neural network (nnet) is considered as the best model to predict the severity of IgAN. Fucose identified from DSigDB has a potential biological activity to treat IgAN.

Conclusion

The increase of macrophages and the decrease of iTregs in glomeruli represent the immune-mediated inflammation of IgAN, and fucose may be a potential therapeutic molecule against IgAN because it affects genes involved in the severe inflammation of IgAN.

The Roles of Immune Cells in Gastric Cancer: Anti-Cancer or Pro-Cancer?

Simple Summary

Gastric cancer is still one of the leading causes of death caused by cancer in developing countries. The emerging role of immunotherapy in cancer treatment has led to more research to elucidate the roles of essential immune cells in gastric cancer prognosis. We reviewed the roles of immune cells including T cells, B cells, dendritic cells, macrophages and natural killer cells in gastric cancer. Although the studies conducted on the roles of immune cells in gastric cancer pathogenesis produced conflicting results, understanding the roles of immune cells in gastric cancer will help us to harness them for application in immunotherapy for better prognosis and management of gastric cancer patients.

Abstract

Despite the fact that the incidence of gastric cancer has declined over the last decade, it is still the world’s leading cause of cancer-related death. The diagnosis of early gastric cancer is difficult, as symptoms of this cancer only manifest at a late stage of cancer progression. Thus, the prognosis of gastric cancer is poor, and the current treatment for improving patients’ outcomes involves the application of surgery and chemotherapy. Immunotherapy is one of the most recent therapies for gastric cancer, whereby the immune system of the host is programmed to combat cancer cells, and the therapy differs based upon the patient’s immune system. However, an understanding of the role of immune cells, namely the cell-mediated immune response and the humoral immune response, is pertinent for applications of immunotherapy. The roles of immune cells in the prognosis of gastric cancer have yielded conflicting results. This review discusses the roles of immune cells in gastric cancer pathogenesis, specifically, T cells, B cells, macrophages, natural killer cells, and dendritic cells, as well as the evidence presented thus far. Understanding how cancer cells interact with immune cells is of paramount importance in designing treatment options for gastric cancer immunotherapy.

Advanced Biomaterials for Cell-Specific Modulation and Restore of Cancer Immunotherapy

The past decade has witnessed the explosive development of cancer immunotherapies. Nevertheless, low immunogenicity, limited specificity, poor delivery efficiency, and off-target side effects remain to be the major limitations for broad implementation of cancer immunotherapies to patient bedside. Encouragingly, advanced biomaterials offering cell-specific modulation of immunological cues bring new solutions for improving the therapeutic efficacy while relieving side effect risks. In this review, focus is given on how functional biomaterials can enable cell-specific modulation of cancer immunotherapy within the cancer-immune cycle, with particular emphasis on antigen-presenting cells (APCs), T cells, and tumor microenvironment (TME)-resident cells. By reviewing the current progress in biomaterial-based cancer immunotherapy, here the aim is to provide a better understanding of biomaterials' role in targeting modulation of antitumor immunity step-by-step and guidelines for rationally developing targeting biomaterials for more personalized cancer immunotherapy. Moreover, the current challenge and future perspective regarding the potential application and clinical translation will also be discussed.

LncRNA-miRNA network analysis across the Th17 cell line reveals biomarker potency of lncRNA NEAT1 and KCNQ1OT1 in multiple sclerosis

Differentiation of CD⁴⁺ T cells into Th17 cells is an important factor in the onset and progression of multiple sclerosis (MS) and Th17/Treg imbalance. Little is known about the role of lncRNAs in the differentiation of CD⁴⁺ cells from Th17 cells. This study aimed to analyse the lncRNA‐miRNAs network involved in MS disease and its role in the differentiation of Th17 cells. The lncRNAs in Th17 differentiation were obtained from GSE66261 using the GEO datasets. Differential expression of lncRNAs in Th17 primary cells compared to Th17 effector cells was investigated by RNA‐seq analysis. Next, the most highlighted lncRNAs in autoimmune diseases were downloaded from the lncRNAs disease database, and the most critical miRNA was extracted by literature search. Then, the lncRNA‐miRNA interaction was achieved by the Starbase database, and the ceRNA network was designed by Cytoscape. Finally, using the CytoHubba application, two hub lncRNAs with the most interactions with miRNAs were identified by the MCODE plug‐in. The expression level of genes was measured by qPCR, and the plasma level of cytokines was analysed by ELISA kits. The results showed an increase in the expression of NEAT1, KCNQ1OT1 and RORC and a decrease in the expression of FOXP3. In plasma, an upregulation of IL17 and a downregulation of TGFB inflammatory cytokines were detected. The dysregulated expression of these genes could be attributed to relapsing‐remitting MS (RR‐MS) patients and help us understand MS pathogenesis better.

Systems-based approaches to study immunometabolism

Technical advances at the interface of biology and computation, such as single-cell RNA-sequencing (scRNA-seq), reveal new layers of complexity in cellular systems. An emerging area of investigation using the systems biology approach is the study of the metabolism of immune cells. The diverse spectra of immune cell phenotypes, sparsity of immune cell numbers in vivo, limitations in the number of metabolites identified, dynamic nature of cellular metabolism and metabolic fluxes, tissue specificity, and high dependence on the local milieu make investigations in immunometabolism challenging, especially at the single-cell level. In this review, we define the systemic nature of immunometabolism, summarize cell- and system-based approaches, and introduce mathematical modeling approaches for systems interrogation of metabolic changes in immune cells. We close the review by discussing the applications and shortcomings of metabolic modeling techniques. With systems-oriented studies of metabolism expected to become a mainstay of immunological research, an understanding of current approaches toward systems immunometabolism will help investigators make the best use of current resources and push the boundaries of the discipline.

Metabolism Characteristics of Th17 and Regulatory T Cells in Autoimmune Diseases

The abnormal number and functional deficiency of immune cells are the pathological basis of various diseases. Recent years, the imbalance of Th17/regulatory T (Treg) cell underlies the occurrence and development of inflammation in autoimmune diseases (AID). Currently, studies have shown that material and energy metabolism is essential for maintaining cell survival and normal functions and the altered metabolic state of immune cells exists in a variety of AID. This review summarizes the biology and functions of Th17 and Treg cells in AID, with emphasis on the advances of the roles and regulatory mechanisms of energy metabolism in activation, differentiation and physiological function of Th17 and Treg cells, which will facilitate to provide targets for the treatment of immune-mediated diseases.

Cyanidin restores Th17/Treg balance and inhibits T follicular helper cell differentiation via modulation of ROCK2 signaling in an experimental model of rheumatoid arthritis

Disturbed Th17/Treg balance is a critical pathological event in the disease progression of rheumatoid arthritis (RA). Recently, emerging studies have demonstrated that CD4 + T helper follicular (Tfh) cells exacerbates the pathogenic manifestations of RA. Contrarily, our previous report has shown that cyanidin, a flavonoid compound, attenuates disease severity of RA. Howbeit, this study investigated the therapeutic efficacy of cyanidin in relation to Th17/Treg balance and pathogenic Tfh cells in RA. Onto results, cyanidin inhibited increased Th17 cell differentiation and reciprocally improved FoxP3 + Treg cells both in-vivo and in-vitro. Concomitantly, cyanidin abated the detrimental effects of IL-17 via restoration of IL-10 secretion in adjuvant induced arthritic (AIA) rats. Furthermore, cyanidin reduced Tfh cells proportion and IgG levels in AIA rats, thus rectifying Tfh and follicular regulatory T (Tfr) cell ratio. Mechanistically, the restoring effect of cyanidin was associated with blunted activation of ROCK2/STAT3 signaling axis and reciprocal increase in the level of STAT-5 activity. Notwithstanding, cyanidin therapeutic efficacy correlated with specific oral ROCK2 inhibitor KD025 in-vitro. Collectively, these results demonstrate a dual promising therapeutic role of cyanidin via regulating Th17/Treg ratio and Tfh cell differentiation in an experimental model of RA.

Synergistic and additive interactions between receptor signaling networks drive the regulatory T cell versus T helper 17 cell fate choice

CD4+ T cells differentiate into subsets that promote immunity or minimize damage to the host. T helper 17 cells (Th17) are effector cells that function in inflammatory responses. T regulatory cells (Tregs) maintain tolerance and prevent autoimmunity by secreting immunosuppressive cytokines and expressing check point receptors. While the functions of Th17 and Treg cells are different, both cell fate trajectories require T cell receptor (TCR) and TGF-β receptor (TGF-βR) signals, and Th17 polarization requires an additional IL-6 receptor (IL-6R) signal. Utilizing high-resolution phosphoproteomics, we identified that both synergistic and additive interactions between TCR, TGF-βR, and IL-6R shape kinase signaling networks to differentially regulate key pathways during the early phase of Treg versus Th17 induction. Quantitative biochemical analysis revealed that CD4+ T cells integrate receptor signals via SMAD3, which is a mediator of TGF-βR signaling. Treg induction potentiates the formation of the canonical SMAD3/4 trimer to activate a negative feedback loop through kinases PKA and CSK to suppress TCR signaling, phosphatidylinositol metabolism, and mTOR signaling. IL-6R signaling activates STAT3 to bind SMAD3 and block formation of the SMAD3/4 trimer during the early phase of Th17 induction, which leads to elevated TCR and PI3K signaling. These data provide a biochemical mechanism by which CD4+ T cells integrate TCR, TGF-β, and IL-6 signals via generation of alternate SMAD3 complexes that control the development of early signaling networks to potentiate the choice of Treg versus Th17 cell fate.

Intestinal Microbiota and Gene Expression Reveal Similarity and Dissimilarity Between Immune-Mediated Colitis and Ulcerative Colitis

Immune checkpoint inhibitors (ICIs) have become the standard of care for several cancers. However, ICI therapy has also been associated with various immune-related adverse events (irAEs). Clinical manifestations of immune-related colitis resemble those of inflammatory bowel diseases such as ulcerative colitis (UC). The composition of the bowel microflora is thought to influence the development of inflammatory bowel disease and irAE colitis. We profiled the gene expressions and microbe compositions of colonic mucosa from patients with solid cancers receiving anti-PD-L1 antibody treatment; we then compared the expression profiles associated with irAE colitis with those associated with UC. The pathway enrichment analysis revealed functional similarities between inflamed regions of irAE colitis and UC. The common enriched pathways included leukocyte extravasation and immune responses, whereas non-inflamed mucosa from patients with irAE colitis was distinct from patients with UC and was characterized by the recruitment of immune cells. A similarity between the microbiota profiles was also identified. A decreased abundance of Bacteroides species was observed in inflamed regions from both irAE colitis and UC based on a microbiota composition analysis of 16S rDNA sequencing. Pathways associated with molecule transport systems, including fatty acids, were enriched in inflamed and non-inflamed irAE colitis and inflamed UC, similar to Piphillin-inferred KEGG pathways. While UC is characterized by local regions of inflammation, ICI treatment extends to non-inflammatory regions of the colonial mucosa where immune cells are reconstituted. This analysis of the similarity and heterogeneity of irAE colitis and UC provides important information for the management of irAE colitis.

Microbiota and Ocular Diseases

Recent advances have identified significant associations between the composition and function of the gut microbiota and various disorders in organ systems other than the digestive tract. Utilizing next-generation sequencing and multiomics approaches, the microbial community that possibly impacts ocular disease has been identified. This review provides an overview of the literature on approaches to microbiota analysis and the roles of commensal microbes in ophthalmic diseases, including autoimmune uveitis, age-related macular degeneration, glaucoma, and other ocular disorders. In addition, this review discusses the hypothesis of the "gut-eye axis" and evaluates the therapeutic potential of targeting commensal microbiota to alleviate ocular inflammation.

Local delivery strategies to restore immune homeostasis in the context of inflammation

Immune homeostasis is maintained by a precise balance between effector immune cells and regulatory immune cells. Chronic deviations from immune homeostasis, driven by a greater ratio of effector to regulatory cues, can promote the development and propagation of inflammatory diseases/conditions (i.e., autoimmune diseases, transplant rejection, etc.). Current methods to treat chronic inflammation rely upon systemic administration of non-specific small molecules, resulting in broad immunosuppression with unwanted side effects. Consequently, recent studies have developed more localized and specific immunomodulatory approaches to treat inflammation through the use of local biomaterial-based delivery systems. In particular, this review focuses on (1) local biomaterial-based delivery systems, (2) common materials used for polymeric-delivery systems and (3) emerging immunomodulatory trends used to treat inflammation with increased specificity.

Histone H4 lysine 16 acetylation controls central carbon metabolism and diet-induced obesity in mice

Noncommunicable diseases (NCDs) account for over 70% of deaths world-wide. Previous work has linked NCDs such as type 2 diabetes (T2D) to disruption of chromatin regulators. However, the exact molecular origins of these chronic conditions remain elusive. Here, we identify the H4 lysine 16 acetyltransferase MOF as a critical regulator of central carbon metabolism. High-throughput metabolomics unveil a systemic amino acid and carbohydrate imbalance in Mof deficient mice, manifesting in T2D predisposition. Oral glucose tolerance testing (OGTT) reveals defects in glucose assimilation and insulin secretion in these animals. Furthermore, Mof deficient mice are resistant to diet-induced fat gain due to defects in glucose uptake in adipose tissue. MOF-mediated H4K16ac deposition controls expression of the master regulator of glucose metabolism, Pparg and the entire downstream transcriptional network. Glucose uptake and lipid storage can be reconstituted in MOF-depleted adipocytes in vitro by ectopic Glut4 expression, PPARγ agonist thiazolidinedione (TZD) treatment or SIRT1 inhibition. Hence, chronic imbalance in H4K16ac promotes a destabilisation of metabolism triggering the development of a metabolic disorder, and its maintenance provides an unprecedented regulatory epigenetic mechanism controlling diet-induced obesity.

Coxiella burnetii Whole Cell Vaccine Produces a Th1 Delayed-Type Hypersensitivity Response in a Novel Sensitized Mouse Model

Q-VAX®, a whole cell, formalin-inactivated vaccine, is the only vaccine licensed for human use to protect against Coxiella burnetii, the cause of Q fever. Although this vaccine provides long-term protection, local and systemic reactogenic responses are common in previously sensitized individuals which prevents its use outside of Australia. Despite the importance of preventing these adverse reactions to develop widely accepted, novel vaccines against C. burnetii, little is understood about the underlying cellular mechanisms. This is mostly attributed to the use of a guinea pig reactogenicity model where complex cellular analysis is limited. To address this, we compared three different mouse strains develop a model of C. burnetii whole cell vaccine reactogenic responses. SKH1 and C57Bl/6, but not BALBc mice, develop local granulomatous reactions after either infection- or vaccine-induced sensitization. We evaluated local and systemic responses by measuring T cell populations from the vaccination site and spleen during elicitation using flow cytometry. Local reaction sites showed influx of IFNγ+ and IL17a+ CD4 T cells in sensitized mice compared with controls and a reduction in IL4+ CD4 T cells. Additionally, sensitized mice showed a systemic response to elicitation by an increase in IFNγ+ and IL17a+ CD4 T cells in the spleen. These results indicate that local and systemic C. burnetii reactogenic responses are consistent with a Th1 delayed-type hypersensitivity. Our experiments provide insights into the pathophysiology of C. burnetii whole cell vaccine reactogenicity and demonstrate that C57Bl/6 and SKH1 mice can provide a valuable model for evaluating the reactogenicity of novel C. burnetii vaccine candidates.

Metabolic modeling of single Th17 cells reveals regulators of autoimmunity

Metabolism is a major regulator of immune cell function, but it remains difficult to study the metabolic status of individual cells. Here, we present Compass, an algorithm to characterize cellular metabolic states based on single-cell RNA sequencing and flux balance analysis. We applied Compass to associate metabolic states with T helper 17 (Th17) functional variability (pathogenic potential) and recovered a metabolic switch between glycolysis and fatty acid oxidation, akin to known Th17/regulatory T cell (Treg) differences, which we validated by metabolic assays. Compass also predicted that Th17 pathogenicity was associated with arginine and downstream polyamine metabolism. Indeed, polyamine-related enzyme expression was enhanced in pathogenic Th17 and suppressed in Treg cells. Chemical and genetic perturbation of polyamine metabolism inhibited Th17 cytokines, promoted Foxp3 expression, and remodeled the transcriptome and epigenome of Th17 cells toward a Treg-like state. In vivo perturbations of the polyamine pathway altered the phenotype of encephalitogenic T cells and attenuated tissue inflammation in CNS autoimmunity.

Stem cell therapies for autoimmune hepatitis

Autoimmune hepatitis is a chronic inflammatory hepatic disorder which may cause liver fibrosis. Appropriate treatment of autoimmune hepatitis is therefore important. Adult stem cells have been investigated as therapies for a variety of disorders in latest years. Hematopoietic stem cells (HSCs) were the first known adult stem cells (ASCs) and can give rise to all of the cell types in the blood and immune system. Originally, HSC transplantation was served as a therapy for hematological malignancies, but more recently researchers have found the treatment to have positive effects in autoimmune diseases such as multiple sclerosis. Mesenchymal stem cells (MSCs) are ASCs which can be extracted from different tissues, such as bone marrow, adipose tissue, umbilical cord, and dental pulp. MSCs interact with several immune response pathways either by direct cell-to-cell interactions or by the secretion of soluble factors. These characteristics make MSCs potentially valuable as a therapy for autoimmune diseases. Both ASC and ASC-derived exosomes have been investigated as a therapy for autoimmune hepatitis. This review aims to summarize studies focused on the effects of ASCs and their products on autoimmune hepatitis.

Targeting the gut to treat multiple sclerosis

The gut-brain axis (GBA) refers to the complex interactions between the gut microbiota and the nervous, immune, and endocrine systems, together linking brain and gut functions. Perturbations of the GBA have been reported in people with multiple sclerosis (pwMS), suggesting a possible role in disease pathogenesis and making it a potential therapeutic target. While research in the area is still in its infancy, a number of studies revealed that pwMS are more likely to exhibit altered microbiota, altered levels of short chain fatty acids and secondary bile products, and increased intestinal permeability. However, specific microbes and metabolites identified across studies and cohorts vary greatly. Small clinical and preclinical trials in pwMS and mouse models, in which microbial composition was manipulated through the use of antibiotics, fecal microbiota transplantation, and probiotic supplements, have provided promising outcomes in preventing CNS inflammation. However, results are not always consistent, and large-scale randomized controlled trials are lacking. Herein, we give an overview of how the GBA could contribute to MS pathogenesis, examine the different approaches tested to modulate the GBA, and discuss how they may impact neuroinflammation and demyelination in the CNS.

In Vivo Induction of Regulatory T Cells Via CTLA-4 Signaling Peptide to Control Autoimmune Encephalomyelitis and Prevent Disease Relapse

Regulatory T cells play a key role in immune tolerance to self-antigens, thereby preventing autoimmune diseases. However, no drugs targeting Treg cells have been approved for clinical trials yet. Here, a chimeric peptide is generated by conjugation of the cytoplasmic domain of CTLA-4 (ctCTLA-4) with dNP2 for intracellular delivery, dNP2-ctCTLA-4, and evaluated Foxp3 expression during Th0, Th1, Treg, and Th17 differentiation dependent on TGF-β. The lysine motif of ctCTLA-4, not tyrosine motif, is required for Foxp3 expression for Treg induction and amelioration of experimental autoimmune encephalomyelitis (EAE). Transcriptome analysis reveals that dNP2-ctCTLA-4-treated T cells express Treg transcriptomic patterns with properties of suppressive functions. In addition, the molecular interaction between the lysine motif of ctCTLA-4 and PKC-η is critical for Foxp3 expression. Although both CTLA-4-Ig and dNP2-ctCTLA-4 treatment in vivo ameliorated EAE progression, only dNP2-ctCTLA-4 requires Treg cells for inhibition of disease progression and prevention of relapse. Furthermore, the CTLA-4 signaling peptide is able to induce human Tregs in vitro and in vivo as well as from peripheral blood mononuclear cells (PBMCs) of multiple sclerosis patients. These results collectively suggest that the chimeric CTLA-4 signaling peptide can be used for successful induction of regulatory T cells in vivo to control autoimmune diseases, such as multiple sclerosis.

Mechanisms Driving Immune-Related Adverse Events in Cancer Patients Treated with Immune Checkpoint Inhibitors

PURPOSE OF REVIEW

In the past decade, immune checkpoint inhibitors (ICIs) have revolutionized the field of cancer treatment. With the continuing rise in the number of cancer patients eligible for ICIs, a corresponding rise in immune-related adverse events (irAEs) is occurring. IrAEs are inflammatory reactions against normal, healthy tissue that occur due to ICI-induced activation of the immune system. Although the exact immune pathogenesis driving irAE development remains unknown, we review the main proposed mechanisms, highlighting how they may inform irAE prediction and treatment.

RECENT FINDINGS

IrAEs are common and diverse, varying in incidence, timing, and severity. The possible mechanisms driving irAEs include (1) activation of cytotoxic T cells; (2) activation of B cells and increased autoantibody production; (3) direct molecular mimicry and off-target toxicity; (4) activation of intracellular signaling and pro-inflammatory cytokine production; and (5) environmental modifiers of immune system activation, including composition of the host gut microbiome. These mechanisms may help identify predictive biomarkers and targeted treatment strategies. IrAEs are driven by multiple components of the immune system. More research is needed to understand their immunopathogenesis so that clinicians across all specialties may more effectively monitor and manage these increasingly common conditions.

Childhood maltreatment correlates with higher concentration of transforming growth factor beta (TGF-β) in adult patients with major depressive disorder

Transforming growth factor beta (TGF-β), which has a role as a regulatory cytokine, has not been widely investigated in patients with major depressive disorder (MDD) who experienced childhood trauma. The aim of our study was to investigate the differences in circulating TGF-β levels between the patients with major depressive disorder (MDD) with and without child maltreatment (CM) history, and to compare them to the corresponding control subjects' groups (with or without CM). Blood samples were obtained from 55 patients, fulfilling DSM-IV-R criteria for a current MDD episode without psychotic symptoms, and 45 healthy controls, matched for age and gender. Participants were administered the Childhood Trauma Questionnaire (CTQ). Serum TGF-β concentration was determined by enzyme-linked immunosorbent assay. The concentration of TGF-β was significantly higher in patients with MDD with CM history, compared to MDD patients with no CM, as well as both control groups. Furthermore, we have shown that the combined effect of CM history and MDD affected TGF-β levels in adulthood, which was not observed in the control group with CM. These results indicate that MDD patients with the experience of CM have altered immune-regulatory response, and they may constitute a specific subtype within this heterogenic disorder (ecophenotype).

Targeting the resolution pathway of inflammation using Ac2-26 peptide-loaded PEGylated lipid nanoparticles for the remission of rheumatoid arthritis

Rheumatoid arthritis (RA) is a common autoimmune disease characterized by joint inflammation and immune dysfunction. Although various therapeutic approaches have been utilized for the treatment of RA in clinical applications, the low responsiveness of RA patients and undesired systemic toxicity are still unresolved problems. Targeting the resolution pathway of inflammation with pro-resolving mediators would evoke the protective actions of patient for combating the inflammation. Ac2-26, a 25-amino acid peptide derived from Annexin A (a pro-resolving mediator), has shown good efficacy in the treatment of inflammatory disorders. However, the low bioavailability of Ac2-26 peptides hinders their efficacy in vivo. In this paper, we formed PEGylated lipid nanoparticles (LDNPs) by the co-assembly of l-ascorbyl palmitate (L-AP) and N-(carbonyl methoxypolyethylene glycol-2000)-1,2-distearoyl-sn‑glycero-3-phosphoethanolamine (DSPE-PEG2k) to encapsulate and deliver Ac2-26 peptides to the arthritic rats. They showed good stability and biocompatibility. After being intravenously administrated, Ac2-26 peptide-loaded PEGylated lipid nanoparticles (ADNPs) showed the prolonged in vivo circulation time and enhanced accumulation in inflamed sites. In vivo therapeutic evaluations revealed that ADNPs could attenuate synovial inflammation and improve joint pathology. Therefore, the pro-resolving therapeutic strategy using ADNPs is effective in RA treatment.

The Ability of AhR Ligands to Attenuate Delayed Type Hypersensitivity Reaction Is Associated With Alterations in the Gut Microbiota

Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that regulates T cell function. The aim of this study was to investigate the effects of AhR ligands, 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), and 6-Formylindolo[3,2-b]carbazole (FICZ), on gut-associated microbiota and T cell responses during delayed-type hypersensitivity (DTH) reaction induced by methylated bovine serum albumin (mBSA) in a mouse model. Mice with DTH showed significant changes in gut microbiota including an increased abundance of Bacteroidetes and decreased Firmicutes at the phylum level. Also, there was a decrease in Clostridium cluster XIV and IV, which promote anti-inflammatory responses, and an increase in Prevotella copri that facilitates pro-inflammatory responses. Interestingly, treatment of mice with TCDD attenuated the DTH response, induced Tregs, suppressed Th17 cells in the mesenteric lymph nodes (MLNs), and reversed the gut microbiota composition toward normalcy. In contrast, FICZ exacerbated the DTH response, induced heightened Th17 cells, and failed to cause a major shift in gut microbiota. Furthermore, TCDD but not FICZ caused an increase in the levels of short-chain fatty acids (SCFA), n-butyric acid, and acetic acid. Administration of sodium butyrate into mice with DTH suppressed the response, increased Tregs, and reduced Th17 cells IL17. Butyrate also caused an increase in the abundance of Clostridium and a decrease in Prevotella. Lastly, TCDD, as well as butyrate but not FICZ, were able to inhibit proinflammatory Histone deacetylases (HDACs) class I and II. Together, our data suggest that AhR ligands, such as TCDD that suppress DTH response, may mediate this effect by reversing the gut dysbiosis induced during this inflammatory response, while FICZ may fail to suppress the DTH response because of its inability to overturn the dysbiosis.

Selective activation of cannabinoid receptor 2 regulates Treg/Th17 balance to ameliorate neutrophilic asthma in mice

Background

The cannabinoid receptor 2 (CNR2) plays a critical role in relieving asthma, with the mechanism still unclear. We aimed to investigate the mechanism of the CNR2 agonist (β-caryophyllene, β-Car) in regulating the balance of regulatory T cells (Treg) and T helper cell 17 (Th17) and thus its role in asthma.

Methods

The study group of 50 pathogen-free female BALB/c mice were randomly divided at 6–8 weeks old into five groups of Control, Asthma, Asthma + β-Car (10 mg/kg), Asthma + β-Car + SR144528 (specific CNR2 antagonist, 3 mg/kg), and Asthma + β-Car + CMD178 (inhibitor of Treg cell, 10 mg/kg). ELISA was conducted to evaluate the main inflammatory cytokines [interleukin (IL)-6, IL-8, and tumor necrosis factor-α], and those secreted by Treg (transforming growth factor-β and IL-10), and Th17 (IL-17A and IL-22). Markers of Treg and Th17 cells were assessed by flow cytometry. In vitro, the CD4⁺ T cells were sorted and directed to differentiate to Treg and Th17 cells. The expression levels of CNR2, STAT5 and JNK1/2 were investigated by western blot and immunofluorescence assay.

Results

β-Car relieved neutrophilic asthma severity in mice by elevating the marker genes’ expression of Treg and inhibiting those of Th17, causing an increased proportion of Treg to Th17. β-Car also promoted the directed differentiation of CD4⁺ T cells into Treg, but not Th17. Activation of the CNR2 regulated the Treg/Th17 balance and relieved neutrophilic asthma possibly through promotion of phosphorylation of STAT5 and JNK1/2.

Conclusions

The effect of the selective CNR2 agonist activating STAT5 and JNK1/2 signaling was to change the Treg/Th17 balance and reduce the inflammatory reaction, thus ameliorating neutrophilic asthma in a mouse model.

CAR- and TRuC-redirected regulatory T cells differ in capacity to control adaptive immunity to FVIII

Regulatory T cells (Tregs) control immune responses in autoimmune disease, transplantation, and enable antigen-specific tolerance induction in protein-replacement therapies. Tregs can exert a broad array of suppressive functions through their T cell receptor (TCR) in a tissue-directed and antigen-specific manner. This capacity can now be harnessed for tolerance induction by "redirecting" polyclonal Tregs to overcome low inherent precursor frequencies and simultaneously augment suppressive functions. With the use of hemophilia A as a model, we sought to engineer antigen-specific Tregs to suppress antibody formation against the soluble therapeutic protein factor (F)VIII in a major histocompatibility complex (MHC)-independent fashion. Surprisingly, high-affinity chimeric antigen receptor (CAR)-Treg engagement induced a robust effector phenotype that was distinct from the activation signature observed for endogenous thymic Tregs, which resulted in the loss of suppressive activity. Targeted mutations in the CD3ζ or CD28 signaling motifs or interleukin (IL)-10 overexpression were not sufficient to restore tolerance. In contrast, complexing TCR-based signaling with single-chain variable fragment (scFv) recognition to generate TCR fusion construct (TRuC)-Tregs delivered controlled antigen-specific signaling via engagement of the entire TCR complex, thereby directing functional suppression of the FVIII-specific antibody response. These data suggest that cellular therapies employing engineered receptor Tregs will require regulation of activation thresholds to maintain optimal suppressive function.

Treatment and mechanism of fecal microbiota transplantation in mice with experimentally induced ulcerative colitis

Restoring intestinal microbiota dysbiosis with fecal microbiota transplantation is considered as a promising treatment for ulcerative colitis. However, the mechanisms underlying its relieving effects remain unclear. Ulcerative colitis pathogenesis is associated with the involvement of immune cells and inflammatory cytokines. Here, we aimed to investigate the effect of fecal microbiota transplantation on T cell cytokines in a dextran sulfate sodium-induced ulcerative colitis mouse model. Five-aminosalicylic acid (5-ASA) was used as the positive control. Male C57BL/6 mice were randomly assigned to control, model (UC), UC + FMT, and UC + 5-ASA groups. Each group consisted of five mice. The establishment of the mouse model was verified by fecal occult-blood screening and hematoxylin-eosin staining. Results showed that fecal microbiota transplantation reduced colonic inflammation, significantly decreased T helper (Th)1 and Th17 cells, interferon-gamma, interleukin-2 and interleukin-17, as well as significantly increased Th2 and regulatory T (Treg) cells, interleukin-4, interleukin-10, and transforming growth factor-beta, and improved routine blood count. Furthermore, 16S rRNA gene-sequencing analysis showed a significant increase in the relative abundance of genus Akkermansia and a significant decrease in the relative abundance of genus Helicobacter in the ulcerative colitis group. Fecal microbiota transplantation restored the profile of the intestinal microbiota to that of the control group. These findings demonstrated the capability of fecal microbiota transplantation in controlling experimentally induced ulcerative colitis by improving Th1/Th2 and Th17/Treg imbalance through the regulation of intestinal microbiota.

Sensing the world and its dangers: An evolutionary perspective in neuroimmunology

Detecting danger is key to the survival and success of all species. Animal nervous and immune systems cooperate to optimize danger detection. Preceding studies have highlighted the benefits of bringing neurons into the defense game, including regulation of immune responses, wound healing, pathogen control, and survival. Here, we summarize the body of knowledge in neuroimmune communication and assert that neuronal participation in the immune response is deeply beneficial in each step of combating infection, from inception to resolution. Despite the documented tight association between the immune and nervous systems in mammals or invertebrate model organisms, interdependence of these two systems is largely unexplored across metazoans. This review brings a phylogenetic perspective of the nervous and immune systems in the context of danger detection and advocates for the use of non-model organisms to diversify the field of neuroimmunology. We identify key taxa that are ripe for investigation due to the emergence of key evolutionary innovations in their immune and nervous systems. This novel perspective will help define the primordial principles that govern neuroimmune communication across taxa.

Galangin ameliorates experimental autoimmune encephalomyelitis in mice via modulation of cellular immunity

Multiple sclerosis (MS) causes neurologic disabilities that effect musculature, sensory systems, and vision. This is largely due to demyelination of nerve fibers caused by chronic inflammation. Corticosteroid treatments ameliorate symptoms of MS, but do not successfully cure the disease itself. In the current study, the application of galangin, a phytochemical flavonoid extracted from the ginger family of Alpinis officinarum, on experimental autoimmune encephalomyelitis (EAE; mouse model for MS) was explored. This study investigated prophylactic and therapeutic activity of the drug and mechanisms by which it acts. The results revealed that galangin at 40 and 80 mg/kg could lower the incidence rate of MS, and alleviate clinical/pathological manifestations. Mice administered galangin presented with less limb paralysis, lower levels of inflammatory cell infiltrates, and decreased demyelination compared to vehicle controls. Levels of CD4⁺IFNγ⁺ (T_H1) and CD4⁺IL-17A⁺ (T_H17) cells in the spinal cords of EAE mice administered galangin were reduced and both cell types were not capable of expansion. More surprisingly, galangin inhibited antigen presentation and cytokine production by dendritic cells (DC). Formation of cytokines like IL-6, IL-12, and IL-23 were significantly decreased due to galangin in co-culture models of DC and T-cells. Taken together, the data lead one to conclude that galangin could potentially be used as a potent immunoregulatory agent to alleviate clinical symptoms and reduce the prevalence of MS.

Altered Th17/Treg ratio as a possible mechanism in pathogenesis of idiopathic membranous nephropathy

Idiopathic membranous nephropathy (IMN) as a single organ autoimmune disease is a main cause of nephrotic syndrome in adults which is determined through autoantibodies to podocytes proteins. Th17/regulatory T (Treg) balance has emerged as a prominent factor in the regulation of autoimmunity. In this study, we evaluated the balance of Th17 and Treg cells, expression level of related master transcription factors, cytokines and microRNAs in mononuclear cells of peripheral blood of 30 patients with IMN and 30 healthy individuals before treatment. No significant variation was observed in Th17 cell frequency, retinoic acid receptor-related orphan nuclear receptor γt (RORɣt), signal transducer and Activator of transcription 3(STAT3), IL-17, and IL-23, while IL-21, IL-4, and IL-10 had significant increase in mRNA expression and protein level of peripheral blood mononuclear cells in IMN cases. Reduction in the percentage of Treg cells was also accompanied with significantly decreased expression of Forkhead box P3(FOXP3) and Transforming growth factor beta(TGF-β) in IMN patients compared to the control group. Our study revealed that Th17 cells themselves might not be engaged in the pathogenesis of newly diagnosed patients with IMN; however, decreased T reg cells and increased ratio of Th17/Treg lymphocytes might display a role in the pathogenesis of IMN before treatment.

Differences in Regulatory Mechanisms Induced by β-Lactoglobulin and κ-Casein in Cow's Milk Allergy Mouse Model-In Vivo and Ex Vivo Studies

The presence of various proteins, including modified ones, in food which exhibit diverse immunogenic and sensitizing properties increases the difficulty of predicting host immune responses. Still, there is a lack of sufficiently reliable and comparable data and research models describing allergens in dietary matrices. The aim of the study was to estimate the immunomodulatory effects of β-lactoglobulin (β-lg) in comparison to those elicited by κ-casein (κ-CN), in vivo and ex vivo, using naïve splenocytes and a mouse sensitization model. Our results revealed that the humoral and cellular responses triggered by β-lg and κ-CN were of diverse magnitudes and showed different dynamics in the induction of control mechanisms. β-Lg turned out to be more immunogenic and induced a more dominant Th1 response than κ-CN, which triggered a significantly higher IgE response. For both proteins, CD4⁺ lymphocyte profiles correlated with CD4⁺CD25⁺ and CD4⁺CD25⁺Foxp3⁺ T cells induction and interleukin 10 secretion, but β-lg induced more CD4⁺CD25⁺Foxp3^- Tregs. Moreover, ex vivo studies showed the risk of interaction of immune responses to different milk proteins, which may exacerbate allergy, especially the one caused by β-lg. In conclusion, the applied model of in vivo and ex vivo exposure to β-lg and κ-CN showed significant differences in immunoreactivity of the tested proteins (κ-CN demonstrated stronger allergenic potential than β-lg), and may be useful for the estimation of allergenic potential of various food proteins, including those modified in technological processes.

Serum and Glucocorticoid-Inducible Kinase 1 (SGK1) in NSCLC Therapy

Non-small cell lung cancer (NSCLC) remains the most prevalent and one of the deadliest cancers worldwide. Despite recent success, there is still an urgent need for new therapeutic strategies. It is also becoming increasingly evident that combinatorial approaches are more effective than single modality treatments. This review proposes that the serum and glucocorticoid-inducible kinase 1 (SGK1) may represent an attractive target for therapy of NSCLC. Although ubiquitously expressed, SGK1 deletion in mice causes only mild defects of ion physiology. The frequent overexpression of SGK1 in tumors is likely stress-induced and provides a therapeutic window to spare normal tissues. SGK1 appears to promote oncogenic signaling aimed at preserving the survival and fitness of cancer cells. Most importantly, recent investigations have revealed the ability of SGK1 to skew immune-cell differentiation toward pro-tumorigenic phenotypes. Future studies are needed to fully evaluate the potential of SGK1 as a therapeutic target in combinatorial treatments of NSCLC. However, based on what is currently known, SGK1 inactivation can result in anti-oncogenic effects both on tumor cells and on the immune microenvironment. A first generation of small molecules to inactivate SGK1 has already been already produced.

Immunotherapy with Checkpoint Inhibitors for Hepatocellular Carcinoma: Where Are We Now?

Immune checkpoint inhibitors (ICIs) are beginning to show promise in the clinical management of hepatocellular carcinoma (HCC). Most recently, the anti-programmed death protein-1 (PD-1) agent atezolizumab combined with bevacizumab demonstrated superiority to sorafenib in a Phase 3 randomised clinical trial in the frontline setting. Other ongoing trials of immunotherapy for HCC are exploring different drug combinations, such as a double checkpoint blockade with PD-1 and anti-Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) agents or with tyrosine kinase inhibitors. Moreover, ICIs are being tested in the adjuvant and neoadjuvant settings trying to resolve long-time unmet needs in HCC. The results of the ongoing trials will be critical to understanding the extent of the therapeutic role of ICIs in the complex and multifaceted clinical scenario of HCC. Still, there are some critical points which need further attention to clarify the best use of ICIs in HCC patients. For instance, the actual eligibility rate of patients in the real-life scenario, the prompt identification and correct management of immune-mediated adverse events, the identification of biomarkers predicting response or resistance, and strategies to prevent the tumour escape from ICI effect.

The Role of Immune Modulation in Pathogenesis of IgA Nephropathy

IgA nephropathy (IgAN) is the most prevalent primary glomerulonephritis worldwide, with diverse clinical manifestations characterized by recurrent gross hematuria or microscopic hematuria, and pathological changes featuring poorly O-galactosylated IgA1 deposition in the glomerular mesangium. Pathogenesis has always been the focus of IgAN studies. After 50 years of research, most scholars agree that IgAN is a group of clinicopathological syndromes with certain common immunopathological characteristics, and multiple mechanisms are involved in its pathogenesis, including immunology, genetics, and environmental or nutritional factors. However, the precise pathogenetic mechanisms have not been fully determined. One hypothesis about the pathogenesis of IgAN suggests that immunological factors are engaged in all aspects of IgAN development and play a critical role. A variety of immune cells (e.g., dendritic cells, NK cells, macrophages, T-lymphocyte subsets, and B-lymphocytes, etc.) and molecules (e.g., IgA receptors, Toll-like receptors, complements, etc.) in innate and adaptive immunity are involved in the pathogenesis of IgAN. Moreover, the abnormality of mucosal immune regulation is the core of IgAN immunopathogenesis. The roles of tonsil immunity or intestinal mucosal immunity, which have received more attention in recent years, are supported by mounting evidence. In this review, we will explore the latest research insights on the role of immune modulation in the pathogenesis of IgAN. With a better understanding of immunopathogenesis of IgAN, emerging therapies will soon become realized.

Management of Myocarditis-Related Cardiomyopathy in Adults

Myocarditis is generally a mild and self-limited consequence of systemic infection of cardiotropic viruses. However, patients can develop a temporary or permanent impairment of cardiac function including acute cardiomyopathy with hemodynamic compromise or severe arrhythmias. In this setting, specific causes of inflammation are associated with variable risks of death and transplantation. Recent translational studies suggest that treatments tailored to specific causes of myocarditis may impact clinical outcomes when added to guideline-directed medical care. This review summarizes recent advances in translational research that influence the utility of endomyocardial biopsy for the management of inflammatory cardiomyopathies. Emerging therapies for myocarditis based on these mechanistic hypotheses are entering clinical trials and may add to the benefits of established heart failure treatment.