SOCS, Inflammation, and Autoimmunity

Cancer vaccine designed from homologous ferritin-based fusion protein with enhanced DC-T cell crosstalk for durable adaptive immunity against tumors

Peptide vaccines based on tumor antigens face the challenges of rapid clearance of peptides, low immunogenicity, and immune suppressive tumor microenvironment. However, the traditional solution mainly uses exogenous substances as adjuvants or carriers to enhance innate immune responses, but excessive inflammation can damage adaptive immunity. In the current study, we propose a straightforward novel nanovaccine strategy by employing homologous human ferritin light chain for minimized innate immunity and dendritic cell (DC) targeting, the cationic KALA peptide for enhanced cellular uptake, and suppressor of cytokine signaling 1 (SOCS1) siRNA for modulating DC activity. Upon fusing with the KALA peptide, this nanovaccine presents as a novel 40-mer cage structure, with highly enriched antigen peptides of proper size (25 nm) for targeted delivery to lymph nodes. The loading of SOCS1 siRNA onto the KALA peptide promoted DC maturation in tumor environment, leading to a 3-fold increase in antigen presentation compared to alum adjuvant. Moreover, it demonstrates remarkable efficacy in suppressing tumor progression and metastasis, together with prolonged survival. In addition, the nanovaccine stimulates up to 40 % memory T cells, thereby achieving sustained protection against tumor re-challenge. This unprecedented nanovaccine platform can ignite fresh interdisciplinary discussions on interactive strategies for future peptide vaccine development.

Extracellular Vesicle miR-122-5p as a Prognostic Biomarker in Pediatric Classical Hodgkin Lymphoma

Currently, risk stratification for pediatric Hodgkin lymphoma is based on clinical factors such as stage, bulk, and systemic symptoms. Novel minimally invasive biomarkers could enhance both prognosis and treatment strategies. Therefore, the plasma extracellular vesicles' microRNA profile was characterized by small RNA sequencing in 36 classical Hodgkin lymphoma cases and these findings were confirmed in an extended cohort of 86 patients by RT-qPCR. It was found that the levels of miR-122-5p at diagnosis were significantly higher (p-value: 0.0002) in patients who relapsed compared to patients in remission. The 5-year event-free survival of cases with high and low levels of miR-122-5p was 65 ± 7% and 93 ± 4%, respectively. MiR-122-5p levels were significantly associated with clinical events in both univariate (p-value: 0.0009) and multivariate (p-value: 0.0037) analysis (hazard ratio 5.8). Target prediction analysis suggests an involvement in the polarization of immune cells. The phenotypic characterization of peripheral blood mononuclear cells in 12 patients showed significantly increased levels of CD4+ T-cells in cases with high miR-122-5p levels as compared to low levels (p-value: 0.048). Moreover, CCL17 (TARC) and IL-6 plasma levels at diagnosis were significantly higher as compared to healthy donors (p-value: ≤0.0001). MiR-122-5p could complement current prognostic assays to identify patients at high risk of relapse.

Unique transcriptomic profile of peripheral blood monocytes in rheumatoid arthritis-associated interstitial lung disease

OBJECTIVES

Though interstitial lung disease (ILD) contributes to excess morbidity and mortality in rheumatoid arthritis (RA), RA-ILD pathogenesis remains incompletely defined. As intermediate, non-classical and suppressed CD14+ monocytes are expanded in RA-ILD, this study sought to characterize gene expression profiles of circulating monocytes in RA-ILD.

METHODS

Peripheral blood mononuclear cells were collected from patients with RA without lung disease (N = 5), RA-ILD (N = 5), idiopathic pulmonary fibrosis (IPF; N = 5), and controls without lung and autoimmune disease (N = 4). RNA was extracted from CD14+ isolated monocytes and subjected to transcriptional analysis of 1365 genes. Gene enrichment and pathway analyses were performed.

RESULTS

Unsupervised clustering grouped patients with RA-ILD together with IPF for myeloid innate genes. For fibrosis genes, patients with RA-ILD clustered independent of comparator groups. There were 103, 66, and 64 upregulated and 66, 14, and 25 downregulated genes for RA-ILD, RA, and IPF, vs controls, respectively. For RA-ILD, there was increased expression of genes involved in regulating inflammation and fibrosis (SOCS3, CECAM1, LTB4R2, CLEC7A, IRF7, PHYKPL, GBP5, RAPGEF), epigenetic modification (KDM5D, KMT2D, OGT), and macrophage activation. Top canonical pathways included macrophage differentiation-activation, IL-12, neuroinflammatory, glucocorticoid receptor, and IL-27 signalling.

CONCLUSIONS

Circulating monocytes in RA-ILD patients demonstrate unique gene expression profiles with innate immune gene features more aligned with IPF as opposed to RA in the absence of clinical lung disease with fibrosis gene expression that was distinct from RA and IPF. These studies are important for understanding disease pathogenesis and may provide information for future therapeutic targets in RA-ILD.

A patient-based murine model recapitulates human STAT3 gain-of-function syndrome

STAT3 gain-of-function (GOF) variants results in a heterogeneous clinical syndrome characterized by early onset immunodeficiency, multi-organ autoimmunity, and lymphoproliferation. While 191 documented cases with STAT3 GOF variants have been reported, the impact of individual variants on immune regulation and the broad clinical spectrum remains unclear. We developed a Stat3p.L387R mouse model, mirroring a variant identified in a family exhibiting common STAT3 GOF symptoms, and rare phenotypes including pulmonary hypertension and retinal vasculitis. In vitro experiments revealed increased STAT3 phosphorylation, nuclear migration, and DNA binding of the variant. Our Stat3p.L387R model displayed similar traits from previous Stat3GOF strains, such as splenomegaly and lymphadenopathy. Notably, Stat3p.L387R/+ mice exhibited heightened embryonic lethality compared to prior Stat3GOF/+ models and ocular abnormalities were observed. This research underscores the variant-specific pathology in Stat3p.L387R/+ mice, highlighting the ability to recapitulate human STAT3 GOF syndrome in patient-specific transgenic murine models. Additionally, such models could facilitate tailored treatment development.

Microglia-induced neuroinflammation in hippocampal neurogenesis following traumatic brain injury

Traumatic brain injury (TBI) is one of the most causes of death and disability among people, leading to a wide range of neurological deficits. The important process of neurogenesis in the hippocampus, which includes the production, maturation and integration of new neurons, is affected by TBI due to microglia activation and the inflammatory response. During brain development, microglia are involved in forming or removing synapses, regulating the number of neurons, and repairing damage. However, in response to injury, activated microglia release a variety of pro-inflammatory cytokines, chemokines and other neurotoxic mediators that exacerbate post-TBI injury. These microglia-related changes can negatively affect hippocampal neurogenesis and disrupt learning and memory processes. To date, the intracellular signaling pathways that trigger microglia activation following TBI, as well as the effects of microglia on hippocampal neurogenesis, are poorly understood. In this review article, we discuss the effects of microglia-induced neuroinflammation on hippocampal neurogenesis following TBI, as well as the intracellular signaling pathways of microglia activation.

Anti-CTLA-4 treatment suppresses hepatocellular carcinoma growth through Th1-mediated cell cycle arrest and apoptosis

Inhibiting the cytotoxic T-lymphocyte-associated protein-4 (CTLA-4)-mediated immune checkpoint system using an anti-CTLA-4 antibody (Ab) can suppress the growth of various cancers, but the detailed mechanisms are unclear. In this study, we established a monoclonal hepatocellular carcinoma cell line (Hepa1-6 #12) and analyzed the mechanisms associated with anti-CTLA-4 Ab treatment. Depletion of CD4+ T cells, but not CD8+ T cells, prevented anti-CTLA-4 Ab-mediated anti-tumor effects, suggesting dependence on CD4+ T cells. Anti-CTLA-4 Ab treatment resulted in recruitment of interferon-gamma (IFN-g)-producing CD4+ T cells, called T-helper 1 (Th1), into tumors, and neutralization of IFN-g abrogated the anti-tumor effects. Moreover, tumor growth suppression did not require major histocompatibility complex (MHC)-I or MHC-II expression on cancer cells. In vitro studies showed that IFN-g can induce cell cycle arrest and apoptosis in tumor cells. Taken together, these data demonstrate that anti-CTLA-4 Ab can exert its anti-tumor effects through Th1-mediated cell cycle arrest and apoptosis.

18q Deletion Syndrome Presenting with Late-Onset Combined Immunodeficiency

Patients with chromosome 18q deletion syndrome generally experience hypogammaglobulinemia. Herein, we describe two patients with chromosome 18q deletion syndrome who presented with late-onset combined immune deficiency (LOCID), which has not been previously reported. Patient 1 was a 29-year-old male with 18q deletion syndrome, who was being managed for severe motor and intellectual disabilities at the Yamabiko Medical Welfare Center for 26 years. Although the patient had few infections, he developed Pneumocystis pneumonia at the age of 28. Patient 2, a 48-year-old female with intellectual disability and congenital malformations, was referred to Tokyo Medical and Dental University Hospital with abnormal bilateral lung shadows detected on her chest radiography. Computed tomography showed multiple lymphadenopathies and pneumonia. A lymph node biopsy of the inguinal region revealed granulomatous lymphadenitis, and a chromosomal examination revealed 18q deletion. Array-based genomic hybridization analysis revealed deletion at 18q21.32-q22.3 for patient 1 and at 18q21.33-qter for patient 2. Immune status work-up of the two patients revealed panhypogammaglobulinemia, decreased number of memory B cells and naïve CD4+ and/or CD8+ cells, reduced response on the carboxyfluorescein diacetate succinimidyl ester T-cell division test, and low levels of T-cell receptor recombination excision circles and Ig κ-deleting recombination excision circles. Consequently, both patients were diagnosed with LOCID. Although patients with 18q deletion syndrome generally experience humoral immunodeficiency, the disease can be further complicated by cell-mediated immunodeficiency, causing combined immunodeficiency. Therefore, patients with 18q deletion syndrome should be regularly tested for cellular/humoral immunocompetence.

Down Syndrome and Autoimmune Disease

Down syndrome is the most common genetic cause of intellectual disability and has previously been associated with a variety of autoimmune disorders affecting multiple organ systems. The high prevalence of autoimmune disease, in conjunction with other inflammatory and infectious diseases, in this population suggests an intrinsic immune dysregulation associated with triplication of chromosome 21. Emerging data on the role of chromosome 21 in interferon activation, cytokine production, and activation of B-cell mediated autoimmunity are emerging hypotheses that may explain the elevated prevalence of autoimmune thyroid disease, celiac disease, type I diabetes, autoimmune skin disease, and a variety of autoimmune neurologic conditions. As the life expectancy for individuals with Down syndrome increases, knowledge of the epidemiology, clinical features, management and underlying causes of these conditions will become increasingly important. Disorders such as Hashimoto's thyroiditis are prevalent in between 13 and 34% of individuals with Down syndrome but only 3% of the neurotypical population, a pattern similarly recognized in individuals with Celiac Disease (5.8% v 0.5-2%), alopecia areata (27.7% v. 2%), and vitiligo (4.4% v. 0.05-1.55%), respectively. Given the chronicity of autoimmune conditions, early identification and management can significantly impact the quality of life of individuals with Down syndrome. This comprehensive review will highlight common clinical autoimmune conditions observed in individuals with Down syndrome and explore our current understanding of the mechanisms of disease in this population.

Hypervolemia in Dialysis Patients Impairs STAT3 Signaling and Upregulates miR-142-3p: Effects on IL-10 and IL-6

Fluid overload in hemodialysis patients (HD) has been proven to be associated with inflammation. Elevated levels of the pro-inflammatory cytokine interleukin-6 (IL-6) appear to be inadequately counterbalanced by the anti-inflammatory cytokine interleukin-10 (IL-10). We initiated a cross-sectional study enrolling 40 HD patients who were categorized by a bioimpedance measurement in normovolemic (N; 23) and hypervolemic (H; 17) groups to test whether IL-10- and IL-6-related signal transduction pathways (signal transducer of transcript 3: STAT3) and/or a post-transcriptional regulating mechanism (miR-142) are impaired by hypervolemia. IL-10/IL-6 transcript and protein production by PBMCs (peripheral blood mononuclear cells) were determined. Phospho-flow cytometry was used to detect the phosphorylated forms of STAT3 (pY705 and pS727). miR-142-3p/5p levels were detected by qPCR. Hypervolemic patients were older, more frequently had diabetes, and showed higher CRP levels. IL-10 transcripts were elevated in H patients but not IL-10 protein levels. In spite of the elevated mRNA expression of the suppressor of cytokine expression 3 (SOCS3), IL-6 mRNA and protein expression were increased in immune cells of H patients. The percentage of cells staining positive for STAT3 (pY705) were comparable in both groups; in STAT3 (pS727), however, the signal needed for full transactivation was decreased in H patients. miR-142-3p, a proven target of IL-10 and IL-6, was significantly elevated in H patients. Insufficient phosphorylation of STAT3 may impair inflammatory and anti-inflammatory cytokine signaling. How far degradative mechanisms induced by elevated miR-142-3p levels contribute to an inefficient anti-inflammatory IL-10 signaling remains elusive.

Suppressor of cytokine signaling 3-derived peptide as a therapeutic for inflammatory and oxidative stress-induced damage to the retina

Purpose

Inflammation and oxidative stress contribute to age-related macular degeneration (AMD) and other retinal diseases. We tested a cell-penetrating peptide from the kinase inhibitory region of an intracellular checkpoint inhibitor suppressor of cytokine signaling 3 (R9-SOCS3-KIR) peptide for its ability to blunt the inflammatory or oxidative pathways leading to AMD.

Methods

We used anaphylatoxin C5a to mimic the effect of activated complement, lipopolysaccharide (LPS), and tumor necrosis factor alpha (TNFα) to stimulate inflammation and paraquat to induce mitochondrial oxidative stress. We used a human retinal pigment epithelium (RPE) cell line (ARPE-19) as proliferating cells and a mouse macrophage cell line (J774A.1) to follow cell propagation using microscopy or cell titer assays. We evaluated inflammatory pathways by monitoring the nuclear translocation of NF-κB p65 and mitogen-activated protein kinase p38. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot were used to evaluate the induction of inflammatory markers. In differentiated ARPE-19 monolayers, we evaluated the integrity of tight junction proteins through microscopy and the measurement of transepithelial electrical resistance (TEER). We used intraperitoneal injection of sodium iodate in mice to test the ability of R9-SOC3-KIR to prevent RPE and retinal injury, as assessed by fundoscopy, optical coherence tomography, and histology.

Results

R9-SOCS3-KIR treatment suppressed C5a-induced nuclear translocation of the NF-kB activation domain p65 in undifferentiated ARPE-19 cells. TNF-mediated damage to tight junction proteins in RPE, and the loss of TEER was prevented in the presence of R9-SOCS3-KIR. Treatment with the R9-SOCS3-KIR peptide blocked the C5a-induced expression of inflammatory genes. The R9-SOCS3-KIR treatment also blocked the LPS-induced expression of interleukin-6, MCP1, cyclooxygenase 2, and interleukin-1 beta. R9-SOCS3-KIR prevented paraquat-mediated cell death and enhanced the levels of antioxidant effectors. Daily eye drop treatment with R9-SOCS3-KIR protected against retinal injury caused by i.p. administration of sodium iodate.

Conclusions

R9-SOCS3-KIR blocks the induction of inflammatory signaling in cell culture and reduces retinal damage in a widely used RPE/retinal oxidative injury model. As this peptide can be administered through corneal instillation, this treatment may offer a convenient way to slow down the progression of ocular diseases arising from inflammation and chronic oxidative stress.

mRNA Lipid Nanoparticles for Ex Vivo Engineering of Immunosuppressive T Cells for Autoimmunity Therapies

Cell-based therapies for autoimmune diseases have gained significant traction, with several approaches centered around the regulatory T (Treg) cell─a well-known immunosuppressive cell characterized by its expression of the transcription factor Foxp3. Unfortunately, due to low numbers of Treg cells available in circulation, harvesting and culturing Treg cells remains a challenge. It has been reported that engineering Foxp3 expression in CD4+ T cells can result in a Treg-like phenotype; however, current methods result in the inefficient engineering of these cells. Here, we develop an ionizable lipid nanoparticle (LNP) platform to effectively deliver Foxp3 mRNA to CD4+ T cells. We successfully engineer CD4+ T cells into Foxp3-T (FP3T) cells that transiently exhibit an immunosuppressive phenotype and functionally suppress the proliferation of effector T cells. These results demonstrate the promise of an LNP platform for engineering immunosuppressive T cells with potential applications in autoimmunity therapies.

Aberrant expression of suppressor of cytokine signaling (SOCS) molecules contributes to the development of allergic diseases

Suppressor of cytokine signalling (SOCS) proteins bind to certain cytokine receptors, Janus kinases and signalling molecules to regulate signalling pathways, thus controlling immune and inflammatory responses. Dysregulated expression of various types of SOCS molecules was indicated in multiple types of allergic diseases. SOCS1, SOCS2, SOCS3, SOCS5, and cytokine-inducible SH2 domain protein (CISH) can differentially exert anti-allergic impacts through different mechanisms, such as suppressing Th2 cell development and activation, reducing eosinophilia, decreasing IgE production, repressing production of pro-allergic chemokines, promoting Treg cell differentiation and activation, suppressing Th17 cell differentiation and activation, increasing anti-allergic Th1 responses, inhibiting M2 macrophage polarization, modulating survival and development of mast cells, reducing pro-allergic activity of keratinocytes, and suppressing pulmonary fibrosis. Although some anti-allergic effects were attributed to SOCS3, it can perform pro-allergic impacts through several pathways, such as promoting Th2 cell development and activation, supporting eosinophilia, boosting pro-allergic activity of eosinophils, increasing IgE production, enhancing the expression of the pro-allergic chemokine receptor, reducing Treg cell differentiation, increasing pro-allergic Th9 responses, as well as supporting mucus secretion and collagen deposition. In this review, we discuss the contrasting roles of SOCS proteins in contexts of allergic disorders to provide new insights regarding the pathophysiology of these diseases and possibly explore SOCS proteins as potential therapeutic targets for alleviating allergies.

Protective effect of juglone on electric field-induced apoptosis and inflammation in liver and kidney tissue in rats

Electric field (EF) has been shown to cause tissue damage mainly through oxidative stress, inflammation, and apoptosis. Thus, juglone (5-hydroxy-1,4-naphthoquinone) (JUG), which has antioxidant and antiapoptotic properties, is thought to be effective against electric field-induced damage. We aimed to investigate whether 50 Hz alternating current (AC) triggers inflammation and apoptosis in rat liver and kidney tissues and evaluate the JUG supplement's estimated protective effect. Twenty-four adult male wistar albino rats were divided into control, EF and EF + JUG groups, each containing eight rats. The EF and EF + JUG groups were exposed to EF while no EF exposure and JUG were applied to the control group. At the end of the experiment, liver and kidney tissues were collected for histological (H&E, caspase-3 and TNF-α for immunohistochemical staining), and genetics (SOCS, caspase-3 and TNF-α, PCR analyses). After routine histological procedures, sections stained with H&E showed significant changes in liver and kidney tissues in the EF group compared to the control group (p < 0.05). Significant protective effects were observed in the building volumes and histopathology in the EF + JUG group (p < 0.05). Our gene expression results increased the expression of caspase-3 and TNF-α in the EF group (p < 0.001). Juglone increased SOCS expression (p < 0.001). These findings were consistent with the anti-apoptotic and anti-inflammatory effects of JUG treatment. We reasoned that exposure to EF damaged rat liver and kidney tissues and administration of JUG alleviated the complications caused by 50 Hz EF.

Sea Cucumber Peptide Alleviates Ulcerative Colitis Induced by Dextran Sulfate Sodium by Alleviating Gut Microbiota Imbalance and Regulating miR-155/SOCS1 Axis in Mice

Sea cucumber peptides have been proven to exhibit a variety of biological activities. Ulcerative colitis (UC) is a chronic disease characterized by diffuse inflammation of the mucosa of the rectum and colon with increasing incidence and long duration, and is difficult to cure. The effect of sea cucumber peptide on UC is currently unknown. In this study, 1.5% dextran sulfate sodium (DSS) was added to the drinking water of mice to induce a UC model, and the daily doses of sea cucumber peptide (SP) solution of 200 mg/kg·BW, 500 mg/kg·BW, and 1000 mg/kg·BW were given to UC mice to detect the relieving effect of SP. The results showed that SP can reduce the disease activity index (DAI) of UC mice induced by DSS and can alleviate colon shortening, intestinal tissue damage, and the loss of intestinal tight junction proteins (Claudin-1, Occludin). SP decreased the spleen index, pro-inflammatory factors (IL-1β, IL-6, TNF-α), and myeloperoxidase (MPO) levels in UC mice. SP can alleviate the imbalance of gut microbiota in UC mice, increase the abundance of the Lachnospiraceae NK4A136 group, Prevotellaceae UCG-001, and Ligilactobacillus, and reduce the abundance of Bacteroides and the Eubacterium rum group, as well as alleviating the decrease in short-chain fatty acid (SCFA) content in the feces of UC mice. Notably, SP inhibited miR-155 expression in the colon tissue of UC mice and increased its target protein, suppressor of cytokine signaling 1 (SOCS1), which acts as an inflammatory inhibitor. In summary, the ameliorative effect of SP on UC may be achieved by improving the imbalance of gut microbiota and regulating the miR-155/SOCS1 axis. This study provides a new idea for developing SP as a nutritional supplement to maintain intestinal health.

Intestinal Epithelial Cell-specific Deletion of Cytokine-inducible SH2-containing Protein Alleviates Experimental Colitis in Ageing Mice

BACKGROUND AND AIMS

The incidence of inflammatory bowel disease [IBD] in the elderly has increased in recent years. However, the mechanisms underlying the ageing-related IBD susceptibility remain elusive. Cytokine-inducible SH2-containing protein [CISH] is involved in regulating metabolism, the expansion of intestinal tuft cells and type-2 innate lymphoid cells, and ageing-related airway inflammation. Here, we investigated the role of CISH in ageing-related colitis susceptibility.

METHODS

CISH and phosphorylated signal transducer and activator of transcription-3 [p-STAT3] levels were evaluated in the colons of ageing mice and older ulcerative colitis [UC] patients. Mice with intestinal epithelial cell-specific knockout of Cish [CishΔIEC] and Cish-floxed mice were administered dextran sodium sulphate [DSS] or trinitrobenzene sulphonic acid [TNBS] to induce colitis. Colonic tissues were analysed in quantitative real-time polymerase chain reaction, immunoblotting, immunohistochemical, and histological staining experiments. Differentially expressed genes from colonic epithelia were analysed by RNA sequencing.

RESULTS

Ageing increased the severity of DSS-induced colitis and the expression of colonic epithelial CISH in mice. CishΔIEC prevented DSS- or TNBS-induced colitis in middle-aged mice but not in young mice. RNA-sequencing analysis revealed that CishΔIEC significantly suppressed DSS-induced oxidative stress and proinflammatory responses. During ageing in the CCD841 cell model, knockdown of CISH decreased ageing-induced oxidative stress and proinflammatory responses, whereas these effects were compromised by knocking down or inhibiting STAT3. The increase in CISH expression was higher in the colonic mucosa of older patients with UC than in that of healthy controls.

CONCLUSIONS

CISH might be a proinflammatory regulator in ageing; therefore, targeted therapy against CISH may provide a novel strategy for treating ageing-related IBD.

Infectious diseases, autoantibodies, and autoimmunity

Infections are known to trigger flares of autoimmune diseases in humans and serve as an inciting cause of autoimmunity in animals. Evidence suggests a causative role of infections in triggering antigen-specific autoimmunity, previous thought mainly through antigen mimicry. However, an infection can induce bystander autoreactive T and B cell polyclonal activation, believed to result in non-pathogenic and pathogenic autoimmune responses. Lastly, epitope spreading in autoimmunity is a mechanism of epitope changes of autoreactive cells induced by infection, promoting the targeting of additional self-epitopes. This review highlights recent research findings, emphasizes infection-mediated autoimmune responses, and discusses the possible mechanisms involved.

Common Variable Immunodeficiency: More Pathways than Roads to Rome

Fifty years have elapsed since the term common variable immunodeficiency (CVID) was introduced to accommodate the many and varied antibody deficiencies being identified in patients with suspected inborn errors of immunity (IEIs). Since then, how the term is understood and applied for diagnosis and management has undergone many revisions, though controversy persists on how exactly to define and classify CVID. Many monogenic disorders have been added under its aegis, while investigations into polygenic, epigenetic, and somatic contributions to CVID susceptibility have gained momentum. Expansion of the overall IEI landscape has increasingly revealed genotypic and phenotypic overlap between CVID and various other immunological conditions, while increasingly routine genotyping of CVID patients continues to identify an incredible diversity of pathophysiological mechanisms affecting even single genes. Though many questions remain to be answered, the lessons we have already learned from CVID biology have greatly informed our understanding of adaptive, but also innate, immunity.

The PBX1/miR-141-miR-200a/EGR2/SOCS3 Axis; Integrative Analysis of Interaction Networks to Discover the Possible Mechanism of MiR-141 and MiR-200a-Mediated Th17 Cell Differentiation

Background

Overexpression of miR-141 and miR-200a is known to be associated with the differentiation of T helper 17 (Th17) cells, which are key players in the pathophysiology of autoimmune disorders. However, the function and governing mechanism of these two microRNAs (miRNAs) in Th17 cell skewing are poorly defined.

Objectives

The aim of the present study was to identify the common upstream transcription factors and downstream target genes of miR-141 and miR-200a to obtain a better insight into the possible dysregulated molecular regulatory networks driving miR-141/miR-200a-mediated Th17 cell development.

Materials and Methods

A consensus-based prediction strategy was applied for in-silico identification of potential transcription factors and putative gene targets of miR-141 and miR-200a. Thereafter, we analyzed the expression patterns of candidate transcription factors and target genes during human Th17 cell differentiation by quantitative real-time PCR and examined the direct interaction between both miRNAs and their potential target sequences using dual-luciferase reporter assays.

Results

According to our miRNA-based and gene-based interaction network analyses, pre-B cell leukemia homeobox (PBX1) and early growth response 2 (EGR2) were respectively taken into account as the potential upstream transcription factor and downstream target gene of miR-141 and miR-200a. There was a significant overexpression of the PBX1 gene during the Th17 cell induction period. Furthermore, both miRNAs could directly target EGR2 and inhibit its expression. As a downstream gene of EGR2, the suppressor of cytokine signaling 3 (SOCS3) was also downregulated during the differentiation process.

Conclusions

These results indicate that activation of the PBX1/miR-141-miR-200a/EGR2/SOCS3 axis may promote Th17 cell development and, therefore, trigger or exacerbate Th17-mediated autoimmunity.

MicroRNA-155 acts as a potential prognostic and diagnostic factor in patients with ankylosing spondylitis by modulating SOCS3

BACKGROUND

Ankylosing spondylitis (AS) is a progressive inflammatory disease. Our primary objective was to explore the role of miR-155 and its targeted factors in AS pathogenesis.

METHODS AND RESULTS

PBMCs were isolated from 30 AS patients and 30 healthy individuals using the Ficoll-hypaque isolation approach. The expression of miR-155 and its associated targets, including Suppressor Of Cytokine Signaling 3 (SOCS3), STAT3, and IL-21, were determined using qT-qPCR. Then, PBMCs were cultured, and the effect of miR-155, SOCS3 siRNA (to suppress its expression), pEFSOCS3 (enforced expression), and their combination were investigated by qRT-PCR and western blotting. We also treated the cultured PBMCs with Brefeldin A, a potent inhibitor of cytokine secretion, to determine its effect on IL-21 expression and secretion. In addition, the association between miR-155 and patients' clinicopathological features was examined. The results showed that miR-155, IL-21, and STAT3 were increased in patients with AS, while SOCS3 had decreasing expression trend. It was also determined that miR-155 alleviates SOCS3 expression and increases IL-21 and STAT3 expression; it had a prominent effect when combined with SOCS3 siRNA. Besides, we showed that simultaneous transfection of miR-155 and pEFSOCS3 had no significant effect on IL-21 and STAT3 expression, revealing that miR-155 could alleviate the enforced expression of SOCS3. It was also proven that Brefledine A led to IL-21 up-regulation or accumulation while relieving its secretion. Also, a significant correlation between miR-155 and pathological features of AS patients was found.

CONCLUSION

miR-155 acts as a potential prognostic and diagnostic biomarker. Its up-regulation leads to the down-regulation of SOCS3 and increased expression of IL-21 and STAT3 as characteristic of TH-17 lymphocytes, leading to worsening inflammatory conditions in patients with AS.

Low Ascorbic Acid Intake Induces Inflammatory Changes in Intestine and Liver of ODS Rats

We previously demonstrated that ascorbic acid (AsA) deficiency, caused by an AsA-free diet, induces inflammatory changes in the liver and intestine of osteogenic disorder Shionogi (ODS) rats that cannot synthesize AsA. However, whether low AsA intake induces inflammatory changes remains unknown. Here, we assessed the inflammatory changes in ODS rats caused by low AsA intake and compared them to ODS rats that were fed a diet supplemented with sufficient amounts of AsA (300 mg/kg). Male ODS rats (12-wk-old) were fed an AsA-free diet (0 ppm group), AsA 20 mg/kg diet (20 ppm group), AsA 40 mg/kg diet (40 ppm group) or AsA 300 mg/kg diet (300 ppm group) for 22 d. The hepatic mRNA levels of acute phase proteins, including C-reactive protein (CRP) and haptoglobin, were higher in the 0 and 20 ppm groups, than in the 300 and 40 ppm groups, but were not significantly higher in the 20 ppm group. Serum CRP concentrations were significantly higher in the 0 and 20 ppm groups than in the 300 and 40 ppm groups. Jejunal and ileal interleukin-1β (IL-1β) mRNA levels were higher in the 0 and 20 ppm groups than in the 300 ppm group. Jejunal and ileal IL-6 mRNA levels tended to be higher in the 0 and 20 ppm groups than in the 300 ppm group. Furthermore, the portal IL-6 concentration gradually increased with decrease in the AsA intake. Thus, inflammatory changes could occur in both AsA-deficient ODS rats and ODS rats with low AsA intake.

CD4+ T Cell Regulatory Network Underlies the Decrease in Th1 and the Increase in Anergic and Th17 Subsets in Severe COVID-19

In this model we use a dynamic and multistable Boolean regulatory network to provide a mechanistic explanation of the lymphopenia and dysregulation of CD4+ T cell subsets in COVID-19 and provide therapeutic targets. Using a previous model, the cytokine micro-environments found in mild, moderate, and severe COVID-19 with and without TGF-β and IL-10 was we simulated. It shows that as the severity of the disease increases, the number of antiviral Th1 cells decreases, while the the number of Th1-like regulatory and exhausted cells and the proportion between Th1 and Th1R cells increases. The addition of the regulatory cytokines TFG-β and IL-10 makes the Th1 attractor unstable and favors the Th17 and regulatory subsets. This is associated with the contradictory signals in the micro-environment that activate SOCS proteins that block the signaling pathways. Furthermore, it determined four possible therapeutic targets that increase the Th1 compartment in severe COVID-19: the activation of the IFN-γ pathway, or the inhibition of TGF-β or IL-10 pathways or SOCS1 protein; from these, inhibiting SOCS1 has the lowest number of predicted collateral effects. Finally, a tool is provided that allows simulations of specific cytokine environments and predictions of CD4 T cell subsets and possible interventions, as well as associated secondary effects.

Therapeutic Efficacy of Novel HDAC Inhibitors SPA3052 and SPA3074 against Intestinal Inflammation in a Murine Model of Colitis

Inflammatory bowel diseases (IBD) are digestive tract disorders that involve chronic inflammation with frequent recurrences. This study aimed to evaluate the efficacy of two novel histone deacetylase 8 (HDAC8) inhibitors, namely, SPA3052 and SPA3074, against dextran sulfate sodium (DSS)-induced experimental colitis. Male C57BL/6N mice were subjected to two cycles of 1.5% DSS followed by treatment with suberoylanilide hydroxamic acid (SAHA), SPA3052, or SPA3074 for 14 days. Our results showed that SPA3074 administration increased (>50%) the expression of occludin, a tight junction protein, which was significantly decreased (>100%) after DSS treatment. Moreover, SPA3074 upregulated suppressor of cytokine signaling 1 (SOCS1) protein expression, which is known to be a key suppressor of T-helper cell differentiation and pro-inflammatory cytokines expression. Furthermore, we observed a decrease in SOCS1-associated Akt phosphorylation and an increase in lower extracellular signal-regulated kinase 1 and 2 phosphorylation, which contributed to lower nuclear factor-kappa B activation. Th2 effector cytokines, especially interleukin-13, were also downregulated by SPA3074 treatment. This study suggests that HDAC8 might be a promising novel target for the development of IBD treatments and that the novel HDAC8 inhibitor SPA3074 is a new candidate for IBD therapeutics.

Protective effect of Moringa oleifera Lam. leaf extract against oxidative stress, inflammation, depression, and apoptosis in a mouse model of hepatic encephalopathy

The present study aimed to assess the antioxidative, anti-inflammatory, antiapoptotic, and anti-depression impacts of Moringa oleifera Lam. leaf ethanolic extract (MOLE) in the hippocampus and cerebral cortex of CCl4-induced hepatic encephalopathy mouse model. High-performance liquid chromatography was used to detect marker compounds: rutin and β-sitosterol. Animals were divided into four groups: vehicle group, CCl4-treated group, MOLE-treated group, and (CCl4 + MOLE) group treated with MOLE for 14 days before CCl4-induced neurotoxicity. MOLE decreased alanine aminotransferase, aspartate aminotransferase, corticosterone, and ammonia levels in serum and improved the antioxidant status of CCl4-treated mice in the hippocampus and cerebral cortex. It reduced the expression of toll-like receptor 4 (TLR4), TLR2, myeloid differentiation primary response 88 (MYD88), and nuclear factor-kappa B (NF-κB) genes and the protein levels of the pro-inflammatory cytokines. MOLE also attenuated apoptosis, as revealed by the reduced expression of caspase3, and prevented histological deterioration. Furthermore, MOLE attenuated CCl4-induced anxiety and depression-like behavioral changes. Collectively, MOLE modulates neuroinflammation, oxidative stress, TLR4/2-MyD88/NF-κB signaling, and apoptosis in the hippocampus and cerebral cortex of the hepatic encephalopathy experimental model.

Novel Hydroxypyridine Compound Protects Brain Cells against Ischemic Damage In Vitro and In Vivo

A non-surgical pharmacological approach to control cellular vitality and functionality during ischemic and/or reperfusion-induced phases of strokes remains extremely important. The synthesis of 2-ethyl-6-methyl-3-hydroxypyridinium gammalactone-2,3-dehydro-L-gulonate (3-EA) was performed using a topochemical reaction. The cell-protective effects of 3-EA were studied on a model of glutamate excitotoxicity (GluTox) and glucose-oxygen deprivation (OGD) in a culture of NMRI mice cortical cells. Ca2+ dynamics was studied using fluorescent bioimaging and a Fura-2 probe, cell viability was assessed using cytochemical staining with propidium iodide, and gene expression was assessed by a real-time polymerase chain reaction. The compound anti-ischemic efficacy in vivo was evaluated on a model of irreversible middle cerebral artery (MCA) occlusion in Sprague-Dawley male rats. Brain morphological changes and antioxidant capacity were assessed one week after the pathology onset. The severity of neurological disorder was evaluated dynamically. 3-EA suppressed cortical cell death in a dose-dependent manner under the excitotoxic effect of glutamate and ischemia/reoxygenation. Pre-incubation of cerebral cortex cells with 10-100 µM 3-EA led to significant stagnation in Ca2+ concentration in a cytosol ([Ca2+]i) of neurons and astrocytes suffering GluTox and OGD. Decreasing intracellular Ca2+ and establishing a lower [Ca2+]i baseline inhibited necrotic cell death in an acute experiment. The mechanism of 3-EA cytoprotective action involved changes in the baseline and ischemia/reoxygenation-induced expression of genes encoding anti-apoptotic proteins and proteins of the oxidative status; this led to inhibition of the late irreversible stages of apoptosis. Incubation of brain cortex cells with 3-EA induced an overexpression of the anti-apoptotic genes BCL-2, STAT3, and SOCS3, whereas the expression of genes regulating necrosis and inflammation (TRAIL, MLKL, Cas-1, Cas-3, IL-1β and TNFa) were suppressed. 3-EA 18.0 mg/kg intravenous daily administration for 7 days following MCA occlusion preserved rats' cortex neuron population, decreased the severity of neurological deficit, and spared antioxidant capacity of damaged tissues. 3-EA demonstrated proven short-term anti-ischemic activity in vivo and in vitro, which can be associated with antioxidant activity and the ability to target necrotic and apoptotic death. The compound may be considered a potential neuroprotective molecule for further pre-clinical investigation.

TiO2 nanoparticles abrogate the protective effect of the Crohn's disease-associated variation within the PTPN22 gene locus

OBJECTIVE

Inflammatory bowel disease (IBD) is a multifactorial condition driven by genetic and environmental risk factors. A genetic variation in the protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene has been associated with autoimmune disorders while protecting from the IBD subtype Crohn's disease. Mice expressing the murine orthologous PTPN22-R619W variant are protected from intestinal inflammation in the model of acute dextran sodium sulfate (DSS)-induced colitis. We previously identified food-grade titanium dioxide (TiO₂, E171) as a neglected IBD risk factor. Here, we investigate the interplay of the PTPN22 variant and TiO₂-mediated effects during IBD pathogenesis.

DESIGN

Acute DSS colitis was induced in wild-type and PTPN22 variant mice (PTPN22-R619W) and animals were treated with TiO₂ nanoparticles during colitis induction. Disease-triggering mechanisms were investigated using bulk and single-cell RNA sequencing.

RESULTS

In mice, administration of TiO₂ nanoparticles abrogated the protective effect of the variant, rendering PTPN22-R619W mice susceptible to DSS colitis. In early disease, cytotoxic CD8⁺ T-cells were found to be reduced in the lamina propria of PTPN22-R619W mice, an effect reversed by TiO₂ administration. Normalisation of T-cell populations correlated with increased Ifng expression and, at a later stage of disease, the promoted prevalence of proinflammatory macrophages that triggered severe intestinal inflammation.

CONCLUSION

Our findings indicate that the consumption of TiO₂ nanoparticles might have adverse effects on the gastrointestinal health of individuals carrying the PTPN22 variant. This demonstrates that environmental factors interact with genetic risk variants and can reverse a protective mechanism into a disease-promoting effect.

Expression of MicroRNAs in Sepsis-Related Organ Dysfunction: A Systematic Review

Sepsis is a critical condition characterized by increased levels of pro-inflammatory cytokines and proliferating cells such as neutrophils and macrophages in response to microbial pathogens. Such processes lead to an abnormal inflammatory response and multi-organ failure. MicroRNAs (miRNA) are single-stranded non-coding RNAs with the function of gene regulation. This means that miRNAs are involved in multiple intracellular pathways and thus contribute to or inhibit inflammation. As a result, their variable expression in different tissues and organs may play a key role in regulating the pathophysiological events of sepsis. Thanks to this property, miRNAs may serve as potential diagnostic and prognostic biomarkers in such life-threatening events. In this narrative review, we collect the results of recent studies on the expression of miRNAs in heart, blood, lung, liver, brain, and kidney during sepsis and the molecular processes in which they are involved. In reviewing the literature, we find at least 122 miRNAs and signaling pathways involved in sepsis-related organ dysfunction. This may help clinicians to detect, prevent, and treat sepsis-related organ failures early, although further studies are needed to deepen the knowledge of their potential contribution.

Potential Natural Biomolecules Targeting JAK/STAT/SOCS Signaling in the Management of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease caused by the dysregulation of cytokines and other immune mediators. JAK/STAT is a classical signal transduction pathway involved in various biological processes, and its dysregulation contributes to the key aspects of AD pathogenesis. Suppressor of cytokine signaling (SOCS) proteins negatively regulate the immune-related inflammatory responses mediated by the JAK/STAT pathway. JAK/STAT-mediated production of cytokines including IL-4, IL-13, IL-31, and TSLP inhibits the expression of important skin barrier proteins and triggers pruritus in AD. The expression of SOCS proteins regulates the JAK-mediated cytokines and facilitates maintaining the skin barrier disruptions seen in AD. STATs are crucial in dendritic-cell-activated Th2 cell differentiation in the skin, releasing inflammatory cytokines, indicating that AD is a Th2-mediated skin disorder. SOCS proteins aid in balancing Th1/Th2 cells and, moreover, regulate the onset and maintenance of Th2-mediated allergic responses by reducing the Th2 cell activation and differentiation. SOCS proteins play a pivotal role in inflammatory cytokine-signaling events that act via the JAK/STAT pathway. Therapies relying on natural products and derived biomolecules have proven beneficial in AD when compared with the synthetic regimen. In this review, we focused on the available literature on the potential natural-product-derived biomolecules targeting JAK/STAT/SOCS signaling, mainly emphasizing the SOCS family of proteins (SOCS1, SOCS3, and SOCS5) acting as negative regulators in modulating JAK/STAT-mediated responses in AD pathogenesis and other inflammatory disorders.

Immunopathogenesis and distinct role of Th17 in Periodontitis: A review

BACKGROUND

Periodontitis is a multifactorial inflammatory disease mediated by the host immune response to dental plaque. Periodontitis is characterized by periodontal bone loss and loss of tooth support. Several studies have corroborated the infiltration of T lymphocytes in periodontitis and correlated the infiltration with chronic inflammation in a dysregulated T cell-mediated immune response. The complexity of the disease has prompted multiple studies aiming to understand T cell-mediated pathogenesis.

HIGHLIGHT

Recent findings have demonstrated the pivotal role of helper T cells in many autoimmune diseases, such as rheumatoid arthritis, which has been conventionally correlated with periodontal bone loss. In contrast, the roles of helper T subsets, Th1, Th2, and particularly Th17, have not been explored. Th17-mediated pathogenesis is a significant aspect of the progression and therapy of periodontitis.

CONCLUSION

In this review, we highlight the complex role of Th17 in the underlying pro-inflammatory cascades mediated by a repertoire of Th17-released molecules and their role in aggravated inflammation in periodontitis. We also summarize recent therapeutics targeting Th17 and related molecules, primarily to ameliorate inflammation and maintain periodontal care.

Structure-Activity Relationship Investigations of Novel Constrained Chimeric Peptidomimetics of SOCS3 Protein Targeting JAK2

SOCS3 (suppressor of cytokine signaling 3) protein suppresses cytokine-induced inflammation and its deletion in neurons or immune cells increases the pathological growth of blood vessels. Recently, we designed several SOCS3 peptidomimetics by assuming as template structures the interfacing regions of the ternary complex constituted by SOCS3, JAK2 (Janus Kinase 2) and gp130 (glycoprotein 130) proteins. A chimeric peptide named KIRCONG chim, including non-contiguous regions demonstrated able to bind to JAK2 and anti-inflammatory and antioxidant properties in VSMCs (vascular smooth muscle cells). With the aim to improve drug-like features of KIRCONG, herein we reported novel cyclic analogues bearing different linkages. In detail, in two of them hydrocarbon cycles of different lengths were inserted at positions i/i+5 and i/i+7 to improve helical conformations of mimetics. Structural features of cyclic compounds were investigated by CD (Circular Dichroism) and NMR (Nuclear Magnetic Resonance) spectroscopies while their ability to bind to catalytic domain of JAK2 was assessed through MST (MicroScale Thermophoresis) assay as well as their stability in biological serum. Overall data indicate a crucial role exerted by the length and the position of the cycle within the chimeric structure and could pave the way to the miniaturization of SOCS3 protein for therapeutic aims.

RNA-seq analysis of murine peyer's patches at 6 and 18 h post infection with Fasciola hepatica metacecariae

Fasciola hepatica is a zoonotic parasite that not only economically burdens the agribusiness sector, but also infects up to 1 million people worldwide, with no commercial vaccine yet available. An ideal vaccine would induce protection in the gut, curtailing the extensive tissue damage associated with parasite's migration from the gut to the bile ducts. The design of such a vaccine requires greater knowledge of gut mucosal responses during the early stage of infection. We examined total mRNA expression of the peyer's patches at 6 and 18 h post F. hepatica infection using RNA sequencing. Differential expression analysis revealed 1341 genes upregulated and 61 genes downregulated at 6 h post infection, while 1562 genes were upregulated and 10 genes downregulated after 18 h. Gene-set enrichment analysis demonstrated that immune specific biological processes were amongst the most downregulated. The Toll-like receptor pathway in particular was significantly affected, the suppression of which is a well-documented immune evasive strategy employed by F. hepatica. In general, the genes identified were associated with suppression of inflammatory responses, helminth induced immune responses and tissue repair/homeostasis. This study provides a rich catalogue of the genes expressed in the early stages of F. hepatica infection, adding to the understanding of early host-parasite interactions and assisting in the design of future studies that look to advance the development of a novel F. hepatica vaccine.

Suppression of Interferon-α Treatment Response by Host Negative Factors in Hepatitis B Virus Infection

Chronic hepatitis B virus (CHB) infection remains a major global public health issue for which there is still lacking effective curative treatment. Interferon-α (IFN-α) and its pegylated form have been approved as an anti-HBV drug with the advantage of antiviral activity and host immunity against HBV infection enhancement, however, IFN-α treatment failure in CHB patients is a challenging obstacle with 70% of CHB patients respond poorly to exogenous IFN-α treatment. The IFN-α treatment response is negatively regulated by both viral and host factors, and the role of viral factors has been extensively illustrated, while much less attention has been paid to host negative factors. Here, we summarized evidence of host negative regulators and parameters involved in IFN-α therapy failure, review the mechanisms responsible for these effects, and discuss the possible improvement of IFN-based therapy and the rationale of combining the inhibitors of negative regulators in achieving an HBV cure.

hsa-MiR-19a-3p and hsa-MiR-19b-3p Are Associated with Spinal Cord Injury-Induced Neuropathic Pain: Findings from a Genome-Wide MicroRNA Expression Profiling Screen

Neuropathic pain in spinal cord injury (SCI) is associated with inflammation in both the peripheral and central nervous system (CNS), which may contribute to the initiation and maintenance of persistent pain. An understanding of factors contributing to neuroinflammation may lead to new therapeutic targets for neuropathic pain. Moreover, novel circulating biomarkers of neuropathic pain may facilitate earlier and more effective treatment. MicroRNAs (miRNAs) are short, non-coding single-stranded RNA that have emerged as important biomarkers and molecular mediators in physiological and pathological conditions. Using a genome-wide miRNA screening approach, we studied differential miRNA expression in plasma from 68 healthy, community-dwelling adults with and without SCI enrolled in ongoing clinical studies. We detected 2367 distinct miRNAs. Of these, 383 miRNAs were differentially expressed in acute SCI or chronic SCI versus no SCI and 71 were differentially expressed in chronic neuropathic pain versus no neuropathic pain. We selected homo sapiens (hsa)-miR-19a-3p and hsa-miR-19b-3p for additional analysis based on p-value, fold change, and their known role as regulators of neuropathic pain and neuroinflammation. Both hsa-miR-19a-3p and hsa-miR-19b-3p levels were significantly higher in those with chronic SCI and severe neuropathic pain versus those with chronic SCI and no neuropathic pain. In confirmatory studies, both hsa-miR-19a-3p and hsa-miR-19b-3p have moderate to strong discriminative ability to distinguish between those with and without pain. After adjusting for opioid use, hsa-miR-19b-3p levels were positively associated with pain interference with mood. Because hsa-miR-19 levels have been shown to change in response to exercise, folic acid, and resveratrol, these studies suggest that miRNAs are potential targets of therapeutic interventions.

One Gene, Many Facets: Multiple Immune Pathway Dysregulation in SOCS1 Haploinsufficiency

Background

Inborn errors of immunity (IEI) present with a large phenotypic spectrum of disease, which can pose diagnostic and therapeutic challenges. Suppressor of cytokine signaling 1 (SOCS1) is a key negative regulator of cytokine signaling, and has recently been associated with a novel IEI. Of patients described to date, it is apparent that SOCS1 haploinsufficiency has a pleiotropic effect in humans.

Objective

We sought to investigate whether dysregulation of immune pathways, in addition to STAT1, play a role in the broad clinical manifestations of SOCS1 haploinsufficiency.

Methods

We assessed impacts of reduced SOCS1 expression across multiple immune cell pathways utilizing patient cells and CRISPR/Cas9 edited primary human T cells.

Results

SOCS1 haploinsufficiency phenotypes straddled across the International Union of Immunological Societies classifications of IEI. We found that reduced SOCS1 expression led to dysregulation of multiple intracellular pathways in immune cells. STAT1 phosphorylation is enhanced, comparably with STAT1 gain-of-function mutations, and STAT3 phosphorylation is similarly reduced with concurrent reduction of Th17 cells. Furthermore, reduced SOCS1 E3 ligase function was associated with increased FAK1 in immune cells, and increased AKT and p70 ribosomal protein S6 kinase phosphorylation. We also found Toll-like receptor responses are increased in SOCS1 haploinsufficiency patients.

Conclusions

SOCS1 haploinsufficiency is a pleiotropic monogenic IEI. Dysregulation of multiple immune cell pathways may explain the variable clinical phenotype associated with this new condition. Knowledge of these additional dysregulated immune pathways is important when considering the optimum management for SOCS1 haploinsufficient patients.

The Role of Lipid and the Benefit of Statin in Augmenting Rifampicin Effectivity for a Better Leprosy Treatment

Although leprosy remains as a serious disease of the skin and nervous system, the current treatment is still lacking in its effectiveness. This literature review will explore the association of lipid and leprosy, as well as the potential of statin and other lipid-lowering agents as adjunctive drugs to combat leprosy. Articles were searched through the PubMed, EBSCOhost, and Google Scholar with the keywords: immunomodulation, lipid-body, lipids, leprosy, Mycobacterium leprae, pathogenesis, rifampin or rifampicin, and statins. A manual searching is also carried out to find an additional relevant information to make this literature review more comprehensive. The literatures showed that lipids are highly correlated with leprosy through alterations in serum lipid profile, metabolism, pathogenesis, and producing oxidative stress. Statins can diminish lipid utilization in the pathogenesis of leprosy and show a mycobactericidal effect by increasing the effectiveness of rifampicin and recover the function of macrophages. In addition, Statins have anti-inflammatory properties which may aid in preventing type I and II reactions in leprosy. Standard multidrug therapy might reduce the efficacy of statins, but the effect is not clinically significant. The statin dose-response curve also allows therapeutic response to be achieved with minimal dose. The various pleiotropic effects of statins make it a potential adjunct to standard treatment for leprosy in the future.

Group 2 innate lymphoid cells are numerically and functionally deficient in the triple transgenic mouse model of Alzheimer's disease

Background

The immune pathways in Alzheimer’s disease (AD) remain incompletely understood. Our recent study indicates that tissue-resident group 2 innate lymphoid cells (ILC2) accumulate in the brain barriers of aged mice and that their activation alleviates aging-associated cognitive decline. The regulation and function of ILC2 in AD, however, remain unknown.

Methods

In this study, we examined the numbers and functional capability of ILC2 from the triple transgenic AD mice (3xTg-AD) and control wild-type mice. We investigated the effects of treatment with IL-5, a cytokine produced by ILC2, on the cognitive function of 3xTg-AD mice.

Results

We demonstrate that brain-associated ILC2 are numerically and functionally defective in the triple transgenic AD mouse model (3xTg-AD). The numbers of brain-associated ILC2 were greatly reduced in 7-month-old 3xTg-AD mice of both sexes, compared to those in age- and sex-matched control wild-type mice. The remaining ILC2 in 3xTg-AD mice failed to efficiently produce the type 2 cytokine IL-5 but gained the capability to express a number of proinflammatory genes. Administration of IL-5, a cytokine produced by ILC2, transiently improved spatial recognition and learning in 3xTg-AD mice.

Conclusion

Our results collectively indicate that numerical and functional deficiency of ILC2 might contribute to the cognitive impairment of 3xTg-AD mice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-021-02202-2.

Corneal Application of R9-SOCS1-KIR Peptide Alleviates Endotoxin-Induced Uveitis

Purpose

Uveitis is an ocular inflammation that can affect individuals of all ages and is a major cause of blindness. We have tested the therapeutic efficacy of a cell penetrating peptide from the kinase inhibitory region of suppressor of cytokine signaling 1, denoted as R9-SOCS1-KIR.

Methods

We stimulated J774A.1 cells with lipopolysaccharide (LPS) in the presence of R9-SOCS1-KIR or its inactive control peptide. Effect on inflammatory pathways was followed by the nuclear translocation of nuclear factor κB p65 subunit and phosphorylated-p38. Synthesis of inflammatory markers induced by LPS was tested by reverse transcriptase polymerase chain reaction, Western blot analysis, and ELISA of cell supernatants. We monitored effects on the barrier properties of a differentiated ARPE-19 monolayer treated with LPS. We treated C57BL/6 mice topically with either R9-SOCS1-KIR or vehicle and injected their eyes intravitreally with LPS. Eyes were analyzed by fundoscopy, fluorescein angiography, optical coherence tomography, histology, Western blotting, multiplex enzyme-linked immunosorbent assay, and flow cytometry.

Results

Treatment with R9-SOCS1-KIR resulted in suppression of signaling through nuclear factor κB and p-p38 pathways. R9-SOCS1-KIR suppressed the expression of inflammatory genes, the secretion of inflammatory makers such as nitric oxide, and IL-1β induced by LPS. Increased permeability of retinal pigment epithelial cell monolayers was prevented. Corneal administration of R9-SOCS1-KIR blocked the acute inflammation observed in LPS-injected mouse eyes.

Conclusions

Treatment with R9-SOCS1-KIR alleviated the inflammatory responses in cell culture. Topical delivery of this peptide on mouse eyes protected against LPS-induced damage.

Translational Relevance

Topical delivery of R9-SOCS1-KIR peptide allows the patient to self-administer the drug, while preventing any systemic effects on unrelated organs.

Streptozotocin activates inflammation-associated signalling and antioxidant response in the lobster cockroach; Nauphoeta cinerea (Blattodea: Blaberidae)

Streptozotocin exhibits tropism to insulin-producing beta-cells in mammals and has been used to model diabetes-like phenotypes in insects. We have previously shown increased brain glucose levels and oxidative stress in STZ-treated nymphs of Nauphoeta cinerea. Here, we validate Nauphoeta cinerea as an experimental organism for studying STZ-induced metabolic disruptions by investigating the potential changes in the expression of inflammation and antioxidant related genes. Cockroaches were injected with 0.8% NaCl, 74 and 740 nmol of STZ. mRNA extracted from the head of cockroaches was used to estimate the RT-qPCR expression of inflammation and antioxidant genes. STZ-treatment upregulated the target genes of the JNK pathway (early growth factor response factor and reaper) but had no effect on PDGF-and VEGF-related factor 1. TOLL 1, the target gene of TOLL/NF-kB pathway was up regulated, while both the activator and target gene of the UPD3/JAK/STAT pathway [unpaired 3 and Suppressor of cytokine signalling at 36E] were upregulated. mRNA levels of primary antioxidants (superoxide dismutase and catalase) were increased in STZ treated nymphs but there was no effect on thioredoxins and Peroxiredoxin 4. Likewise, STZ treatment did not affect the expression of the delta class of the glutathione S-transferase gene family, but the sigma and theta classes of the GST family were upregulated. The STZ-induced N. cinerea gene expression modification demonstrates the involvement of primary antioxidants and the GST detoxification system in the cockroach oxidative stress response and buttresses the proposed crosstalk between inflammatory and redox pathways.

Suppressor of cytokine signalling 3 (SOCS3) expressed in podocytes attenuates glomerulonephritis and suppresses autoantibody production in an imiquimod-induced lupus model

Objective

Recently, podocytes have been recognised not only as a physical barrier to prevent urinary protein loss but also as producers of proinflammatory cytokines. However, the roles of podocytes in the pathogenesis of lupus nephritis (LN) remain largely unknown. This study aims to determine the roles of suppressor of cytokine signalling (SOCS) family members expressed in glomeruli in the regulation of LN.

Methods

We investigated the expression of SOCS family members in glomeruli in murine lupus model induced by repeated epicutaneous administration of the TLR7/8 agonist imiquimod. We also investigated the roles of SOCS3 expressed in podocytes in the imiquimod-induced glomerulonephritis and systemic autoimmunity by using podocyte-specific SOCS3-deficient mice (podocin-Cre x SOCS3^fl/fl mice (SOCS3-cKO mice)). Finally, we investigated the expression of proinflammatory cytokines and chemokines in SOCS3-deficient podocyte cell lines.

Results

qPCR analysis revealed that among SOCS family members, SOCS3 was preferentially induced in glomeruli on epicutaneous administration of imiquimod and that interleukin 6 (IL-6) induced SOCS3 expression in podocyte cell lines. SOCS3-cKO mice exhibited severe glomerulonephritis, high levels of serum creatinine and urine albumin and decreased survival rate compared with control SOCS3-WT mice. Levels of anti-double-strand DNA antibody, SOCS (GC) formation and the numbers of follicular helper T (Tfh) cells and GC B cells in the spleen were higher in SOCS3-cKO mice than those in SOCS3-WT mice. Serum IL-6 levels and expression of IL-6 mRNA in glomeruli were also elevated in SOCS3-cKO mice. IL-6-induced IL-6 expression was enhanced in SOCS3-deficient podocyte cell lines compared with that in SOCS3-sufficient podocyte cell lines.

Conclusion

SOCS3 expressed in podocytes plays protective roles for the development of glomerulonephritis and inhibits autoantibody production in the imiquimod-induced lupus model presumably by suppressing IL-6 production of podocytes.

The role of SOCS proteins in the development of virus- induced hepatocellular carcinoma

Background

Liver cancer has become one of the most common cancers and has a high mortality rate. Hepatocellular carcinoma is one of the most common liver cancers, and its occurrence and development process are associated with chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections.

Main body

The serious consequences of chronic hepatitis virus infections are related to the viral invasion strategy. Furthermore, the viral escape mechanism has evolved during long-term struggles with the host. Studies have increasingly shown that suppressor of cytokine signaling (SOCS) proteins participate in the viral escape process. SOCS proteins play an important role in regulating cytokine signaling, particularly the Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway. Cytokines stimulate the expression of SOCS proteins, in turn, SOCS proteins inhibit cytokine signaling by blocking the JAK-STAT signaling pathway, thereby achieving homeostasis. By utilizing SOCS proteins, chronic hepatitis virus infection may destroy the host’s antiviral responses to achieve persistent infection.

Conclusions

This review provides recent knowledge regarding the role of SOCS proteins during chronic hepatitis virus infection and provides some new ideas for the future treatment of chronic hepatitis.

Suppressor of cytokine signaling-1 mimetic peptides attenuate lymphocyte activation in the MRL/lpr mouse autoimmune model

Autoimmune diseases are driven largely by a pathogenic cytokine milieu produced by aberrantly activated lymphocytes. Many cytokines, including interferon gamma (IFN-γ), utilize the JAK/STAT pathway for signal propagation. Suppressor of Cytokine Signaling-1 (SOCS1) is an inducible, intracellular protein that regulates IFN-γ signaling by dampening JAK/STAT signaling. Using Fas deficient, MRL/MpJ-Faslpr/J (MRL/lpr) mice, which develop lupus-like disease spontaneously, we tested the hypothesis that a peptide mimic of the SOCS1 kinase inhibitory region (SOCS1-KIR) would inhibit lymphocyte activation and modulate lupus-associated pathologies. Consistent with in vitro studies, SOCS1-KIR intraperitoneal administration reduced the frequency, activation, and cytokine production of memory CD8+ and CD4+ T lymphocytes within the peripheral blood, spleen, and lymph nodes. In addition, SOCS1-KIR administration reduced lymphadenopathy, severity of skin lesions, autoantibody production, and modestly reduced kidney pathology. On a cellular level, peritoneal SOCS1-KIR administration enhanced Foxp3 expression in total splenic and follicular regulatory T cells, reduced the effector memory/naïve T lymphocyte ratio for both CD4+ and CD8+ cells, and reduced the frequency of GL7+ germinal center enriched B cells. Together, these data show that SOCS1-KIR treatment reduced auto-reactive lymphocyte effector functions and suggest that therapeutic targeting of the SOCS1 pathway through peptide administration may have efficacy in mitigating autoimmune pathologies.

SOCS3 Expression by Thymic Stromal Cells Is Required for Normal T Cell Development

The suppressor of cytokine signaling 3 (SOCS3) is a major regulator of immune responses and inflammation as it negatively regulates cytokine signaling. Here, the role of SOCS3 in thymic T cell formation was studied in Socs3^fl/flActin-creER mice (Δsocs3) with a tamoxifen inducible and ubiquitous Socs3 deficiency. Δsocs3 thymi showed a 90% loss of cellularity and altered cortico-medullary organization. Thymocyte differentiation and proliferation was impaired at the early double negative (CD4-CD8-) cell stage and apoptosis was increased during the double positive (CD4+CD8+) cell stage, resulting in the reduction of recent thymic emigrants in peripheral organs. Using bone marrow chimeras, transplanting thymic organoids and using mice deficient of SOCS3 in thymocytes we found that expression in thymic stromal cells rather than in thymocytes was critical for T cell development. We found that SOCS3 in thymic epithelial cells (TECs) binds to the E3 ubiquitin ligase TRIM 21 and that Trim21^−/− mice showed increased thymic cellularity. Δsocs3 TECs showed alterations in the expression of genes involved in positive and negative selection and lympho-stromal interactions. SOCS3-dependent signal inhibition of the common gp130 subunit of the IL-6 receptor family was redundant for T cell formation. Together, SOCS3 expression in thymic stroma cells is critical for T cell development and for maintenance of thymus architecture.

[Change in the expression of gene transcription negative regulator SOCS1 in the patients with bronchial asthma and metabolic disorders]

AIM

Comprehensive study of the negative regulation components of cell signaling in the bronchial asthma (BA) patients with metabolic disorders.

MATERIALS AND METHODS

113 people were examined: 63 patients with allergic BA (ABA), 50 patients with a non-allergic variant of the disease (NABA). SOCS1 mRNA expression was evaluated by reverse transcription PCR (RT-PCR). SOCS1 protein expression was investigated by immunoblotting. The determination of cytokine levels was carried out according to the standard protocol on a Bio-Plex flow fluorimeter.

RESULTS

A significant and multidirectional change in the expression of SOCS1 mRNA was found at a body mass index 25 (greater than normal) in ABA and NABA. The positive correlations between SOCS1 mRNA expression and body mass index indicate the regulatory role of SOCS1 in leptin signaling. The spectra of correlations in ABA and NABA are different, it indicates the probable existence of specificity in the pathogenesis of these variants of the diseases.

CONCLUSION

The obtained data allow us to consider the complexity of regulation disorders occurring at different levels of cell signaling. The multifunctionality of the SOCS1 regulator provides complex control of cytokine signaling simultaneously in different signaling pathways in the BA with metabolic disorders.

Working and safety profiles of JAK/STAT signaling inhibitors. Are these small molecules also smart?

The Janus kinase (JAK)/signal transducers and activators of transcription (STAT) pathway is an important intracellular route through which many different extracellular soluble molecules, by reaching membrane receptors, can signal the nucleus. The spectrum of soluble molecules that use the JAK/STAT pathway through their corresponding receptors is quite large (almost 50 different molecules), and includes some cytokines involved in the pathogenesis of many immune-mediated diseases. Such diseases, when left untreated, present an evident hyperactivation of JAK/STAT signaling. Therefore, given the pathogenetic role of JAK/STAT, drugs known as JAK inhibitors (JAKi), that target one or more JAKs, have been developed to counteract JAK/STAT signal hyperactivation. As some hematological malignancies present an intrinsic JAK/STAT hyperactivation due to a JAK mutation, some JAKi have also been successfully used in this context. Regulatory agencies for drug administration in different countries have already approved a few JAKi in the setting of either immune-mediated diseases or hematological malignancies. Aim of this review is to describe the physiology of intracellular JAK/STAT pathway signaling and the pathological conditions associated to its dysregulation. Then, the rationale for targeting JAK in rheumatic autoimmune diseases is discussed, along with clinical data from registration studies showing the efficacy of these drugs. Finally, the excellent safety profile of JAKi is discussed in the context of the apparent poor specificity of JAK/STAT pathway signal.

Reducing Suppressors of Cytokine Signaling-3 (SOCS3) Expression Promotes M2 Macrophage Polarization and Functional Recovery After Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a fatal subtype of stroke, and effective interventions to improve the functional outcomes are still lacking. Suppressor of cytokine signaling 3 (SOCS3) plays critical roles in the inflammatory response by negatively regulating cytokine-Jak-Stat signaling. However, the role of SOCS3 in the regulation of macrophage polarization is highly controversial and the fine regulation exerted by SOCS3 needs further understanding. In this study, rat ICH models were established by infusion of collagenase into the caudate nucleus. To decrease SOCS3 expression into microglia/macrophages in the hemorrhagic lesion area, we injected lentiviral short hairpin RNA (shSOCS3) (Lenti-shSOCS3) into the hematoma cavity at 24 h following ICH. We found that the number of iNOS-positive cells (M1 phenotype) was significantly reduced, whereas arginase-1-positive cells (M2 phenotype) were markedly elevated in animals that received Lenti-shSOCS3 injections compared with those in the Lenti-EGFP and saline groups. The increase in arginase-1-positive cells was associated with a significantly lower pro-inflammatory microenvironment, which included the downregulation of pro-inflammatory cytokines [interleukin (IL)-1β, IL-6, and TNF-α] and concurrent upregulation of anti-inflammatory (IL-10) mediators. In addition, this marked shift toward the M2 phenotype was associated with suppressed NF-κB activation. Furthermore, these changes notably enhanced the neuroprotective effects and functional recovery in Lenti-shSOCS3-injected animals. Our findings indicated that reduction in SOCS3 expression caused a marked bias toward the M2 phenotype and ameliorated the inflammatory microenvironment, which enhanced neuroprotective effects and resulted in notable improvement in functional recovery after ICH.

Rapamycin Alleviates the Symptoms of Multiple Sclerosis in Experimental Autoimmune Encephalomyelitis (EAE) Through Mediating the TAM-TLRs-SOCS Pathway

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS). Our research aimed to find an immunomodulatory therapy for MS. An experimental autoimmune encephalomyelitis (EAE) mouse model of MS was established induced with the syntheticmyelin oligodendrocyte glycoprotein peptide 35-55 (MOG35-55). Fifty C57BL/6 mice were randomly divided into the Normal group, EAE group, and Rapamycin group (EAE mice treated with three different doses of rapamycin). Hematoxylin and eosin staining and Weil myelin staining were performed on the brain tissues of mice after 21 days post-immunization. The protein expression of Gas6, Tyro3, Axl, Mer in paraventricular tissues were analyzed by immunohistochemistry. The mRNA and protein expression of Gas6, Tyro3, Axl, Mer, SOCS1, SOCS3, Toll-like receptor (TLR) 3, and TLR4 were detected by quantitative real-time PCR (qRT-PCR) and Western blot, respectively. An enzyme-linked immunosorbent assay (ELISA) was used to detect the secretion of the inflammatory factors IFN-γ and IL-17. Rapamycin treatment could ameliorate the behavior impairment in EAE mice induced by MOG35-55. The expression of Gas6, Tyro3, Axl, Mer, SOCS1, and SOCS3 were decreased in EAE mice at 21 days post-immunization, while the expression of Gas6, Tyro3, Axl, and Mer in rapamycin group was higher than that in EAE group. It was accompanied by an increase in anti-inflammatory proteins SOCS1 and SOCS3, a decrease in the inflammatory proteins TLR-3, TLR-4 and in the amount of IFN-γ, and IL-17. Rapamycin injection relieved the nerve function of and the loss of myelin sheath in the EAE mice, mainly through mediating the TAM-TLRs-SOCS signaling pathway to regulate natural immunity.

Emerging Roles of Disabled Homolog 2 (DAB2) in Immune Regulation

Disabled-2 (DAB2) is a clathrin and cargo binding endocytic adaptor protein recognized for its multifaceted roles in signaling pathways involved in cellular differentiation, proliferation, migration, tumor suppression, and other fundamental homeostatic cellular mechanisms. The requirement for DAB2 in the canonical TGFβ signaling in fibroblasts suggested that a similar mechanism may exist in immune cells and that DAB2 may contribute to immunological tolerance and suppression of inflammatory responses. In this review, we synthesize the current state of knowledge on the roles of DAB2 in the cells of the innate and adaptive immune system, with particular focus on antigen presenting cells (APCs; macrophages and dendritic cells) and regulatory T cells (Tregs). The emerging role of DAB2 in the immune system is that of an immunoregulatory molecule with significant roles in Treg-mediated immunosuppression, and suppression of TLR signaling in APC. DAB2 itself is downregulated by inflammatory stimuli, an event that likely contributes to the immunogenic function of APC. However, contrary findings have been described in neuroinflammatory disorders, thus suggesting a highly context-specific roles for DAB2 in immune cell regulation. There is need for better understanding of DAB2 regulation and its roles in different immune cells, their specialized sub-populations, and their responses under specific inflammatory conditions.

Suppressor of cytokine signaling proteins 1 and 3 and hepatitis B virus infection

Suppressor of cytokine signaling proteins (SOCS) are cytokine pathway inhibitors that play an important role in regulating the antiviral effect of interferon (IFN). Current studies have shown that SOCS1 and SOCS3 are closely related to hepatitis B virus (HBV) infection. Inhibition or stimulation of SOCS1 and SOCS3 expression may affect the antiviral effect by regulating the production of IFN, and may also affect the pathogenicity of HBV together with other cytokines or transcription regulators. This paper mainly discusses the possible mechanisms of SOCS1 and SOCS3 in HBV infection.

A Novel Selective Sphingosine Kinase 2 Inhibitor, HWG-35D, Ameliorates the Severity of Imiquimod-Induced Psoriasis Model by Blocking Th17 Differentiation of Naïve CD4 T Lymphocytes

Sphingosine kinases (SK) catalyze the phosphorylation of sphingosine to generate sphingosine-1-phosphate. Two isoforms of SK (SK1 and SK2) exist in mammals. Previously, we showed the beneficial effects of SK2 inhibition, using ABC294640, in a psoriasis mouse model. However, ABC294640 also induces the degradation of SK1 and dihydroceramide desaturase 1 (DES1). Considering these additional effects of ABC294640, we re-examined the efficacy of SK2 inhibition in an IMQ-induced psoriasis mouse model using a novel SK2 inhibitor, HWG-35D, which exhibits nM potency and 100-fold selectivity for SK2 over SK1. Topical application of HWG-35D ameliorated IMQ-induced skin lesions and normalized the serum interleukin-17A levels elevated by IMQ. Application of HWG-35D also decreased skin mRNA levels of interleukin-17A, K6 and K16 genes induced by IMQ. Consistent with the previous data using ABC294640, HWG-35D also blocked T helper type 17 differentiation of naïve CD4⁺ T cells with concomitant reduction of SOCS1. Importantly, HWG-35D did not affect SK1 or DES1 expression levels. These results reaffirm an important role of SK2 in the T helper type 17 response and suggest that highly selective and potent SK2 inhibitors such as HWG-35D might be of therapeutic use for the treatment of psoriasis.

A Novel Coronavirus Disease (COVID-19): a Review of Host Cell Signaling Pathways

Coronaviruses (CoVs) are the largest group of positive-sense RNA viruses. By increasing our understanding of the interactions between CoVs and the host innate immune system, we can evaluate the development and persistence of inflammation in the lungs and reduce the risk of CoV-induced lung inflammation with a new group of genetic variants. Here, we aim to discuss some recent changes in host cell factors that may be used by CoV to promote the proliferation cycle. We also discuss different host cell signaling pathways that can be considered in the host-pathogen interactions at the molecular level. The pandemic of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has created new challenges for the cultural, economic, and health infrastructures. Therefore, it is important that healthcare systems and physicians recognize a global integrated framework for monitoring the progression of COVID-19 to develop targeted therapies that can potentially save human lives.