IL-35 is a novel cytokine with therapeutic effects against collagen-induced arthritis through the expansion of regulatory T cells and suppression of Th17 cells

Breakthroughs in road mapping IL-35 mediated immunotherapy for type-1 and autoimmune diabetes mellitus

IL-35 is a recently discovered protein made up of IL-12α and IL-27β chains. It is encoded by IL12A and EBI3 genes. Interest in researching IL-35 has significantly increased in recent years, as evidenced by numerous scientific publications. Diabetes is on the rise globally, causing more illness and death in developing countries. The International Diabetes Federation (IDF) reports that diabetes is increasingly affecting children and teenagers, with varying rates across different regions. Therefore, scientists seek new diabetes treatments despite the growth of drug research. Recent research aims to emphasize IL-35 as a critical regulator of diabetes, especially type 1 and autoimmune diabetes. This review provides an overview of recent research on IL-35 and its link to diabetes and its associated complications. Studies suggest that IL-35 can offer protection against type-1 diabetes and autoimmune diabetes by regulating macrophage polarization, T-cell-related cytokines, and regulatory B cells (Bregs). This review will hopefully assist biomedical scientists in exploring the potential role of IL-35-mediated immunotherapy in treating diabetes. However, further research is necessary to determine the exact mechanism and plan clinical trials.

Interleukin-35 alleviates neuropathic pain and induces an anti-inflammatory shift in spinal microglia in nerve-injured male mice

Immune cells are critical in promoting neuroinflammation and neuropathic pain and in facilitating pain resolution, depending on their inflammatory and immunoregulatory cytokine response. Interleukin (IL)-35, secreted by regulatory immune cells, is a member of the IL-12 family with a potent immunosuppressive function. In this study, we investigated the effects of IL-35 on pain behaviors, spinal microglia phenotype following peripheral nerve injury, and in vitro microglial cultures in male and female mice. Intrathecal recombinant IL-35 treatment alleviated mechanical pain hypersensitivity prominently in male mice, with only a modest effect in female mice after sciatic nerve chronic constriction injury (CCI). IL-35 treatment resulted in sex-specific microglial changes following CCI, reducing inflammatory microglial markers and upregulating anti-inflammatory markers in male mice. Spatial transcriptomics analysis revealed that IL-35 suppressed microglial complement activation in the superficial dorsal horn in male mice after CCI. Moreover, in vitro studies showed that IL-35 treatment of cultured inflammatory microglia mitigated their hypertrophied morphology, increased their cell motility, and decreased their phagocytic activity, indicating a phenotypic shift towards homeostatic microglia. Further, IL-35 altered microglial cytokines/chemokines in vitro, suppressing the release of IL-9 and monocyte-chemoattractant protein-1 and increasing IL-10 in the supernatant of male microglial cultures. Our findings indicate that treatment with IL-35 modulates spinal microglia and alleviates neuropathic pain in male mice, suggesting IL-35 as a potential sex-specific targeted immunomodulatory treatment for neuropathic pain.

IL-27 expression regulation and its effects on adaptive immunity against viruses

IL-27, a member of the IL-6/IL-12 cytokine superfamily, is primarily secreted by antigen presenting cells, specifically by dendric cells, macrophages and B cells. IL-27 has antiviral activities and modulates both innate and adaptive immune responses against viruses. The role of IL-27 in the setting of viral infections is not well defined and both pro-inflammatory and anti-inflammatory functions have been described. Here, we discuss the latest advancements in the role of IL-27 in several viral infection models of human disease. We highlight important aspects of IL-27 expression regulation, the critical cell sources at different stages of the infection and their impact in cell mediated immunity. Lastly, we discuss the need to better define the antiviral and modulatory (pro-inflammatory vs anti-inflammatory) properties of IL-27 in the context of human chronic viral infections.

Upregulation of TCPTP in Macrophages Is Involved in IL-35 Mediated Attenuation of Experimental Colitis

Ulcerative colitis (UC) is a chronic intestinal inflammatory disease with complex etiology. Interleukin-35 (IL-35), as a cytokine with immunomodulatory function, has been shown to have therapeutic effects on UC, but its mechanism is not yet clear. Therefore, we constructed Pichia pastoris stably expressing IL-35 which enables the cytokines to reach the diseased mucosa, and explored whether upregulation of T-cell protein tyrosine phosphatase (TCPTP) in macrophages is involved in the mechanisms of IL-35-mediated attenuation of UC. After the successful construction of engineered bacteria expressing IL-35, a colitis model was successfully induced by giving BALB/c mice a solution containing 3% dextran sulfate sodium (DSS). Mice were treated with Pichia/IL-35, empty plasmid-transformed Pichia (Pichia/0), or PBS by gavage, respectively. The expression of TCPTP in macrophages (RAW264.7, BMDMs) and intestinal tissues after IL-35 treatment was detected. After administration of Pichia/IL-35, the mice showed significant improvement in weight loss, bloody stools, and shortened colon. Colon pathology also showed that the inflammatory condition of mice in the Pichia/IL-35 treatment group was alleviated. Notably, Pichia/IL-35 treatment not only increases local M2 macrophages but also decreases the expression of inflammatory cytokine IL-6 in the colon. With Pichia/IL-35 treatment, the proportion of M1 macrophages, Th17, and Th1 cells in mouse MLNs were markedly decreased, while Tregs were significantly increased. In vitro experiments, IL-35 significantly promoted the expression of TCPTP in macrophages stimulated with LPS. Similarly, the mice in the Pichia/IL-35 group also expressed more TCPTP than that of the untreated group and the Pichia/0 group.

The role of B-1 cells in cancer progression and anti-tumor immunity

In recent years, in addition to the well-established role of T cells in controlling or promoting tumor growth, a new wave of research has demonstrated the active involvement of B cells in tumor immunity. B-cell subsets with distinct phenotypes and functions play various roles in tumor progression. Plasma cells and activated B cells have been linked to improved clinical outcomes in several types of cancer, whereas regulatory B cells have been associated with disease progression. However, we are only beginning to understand the role of a particular innate subset of B cells, referred to as B-1 cells, in cancer. Here, we summarize the characteristics of B-1 cells and review their ability to infiltrate tumors. We also describe the potential mechanisms through which B-1 cells suppress anti-tumor immune responses and promote tumor progression. Additionally, we highlight recent studies on the protective anti-tumor function of B-1 cells in both mouse models and humans. Understanding the functions of B-1 cells in tumor immunity could pave the way for designing more effective cancer immunotherapies.

Effects of smoking on the salivary and GCF levels of IL-17 and IL-35 in periodontitis

Periodontitis progression is associated with a host response in which anti-inflammatory and pro-inflammatory cytokine networks play a key role. Smoking is involved in the production of various mediators. The study aims to evaluate the levels of IL-17 and IL-35 in saliva and gingival crevicular fluid (GCF), to investigate the effects of smoking on these cytokines in smoker and non-smoker periodontitis patients. 19 smokers with periodontitis, 20 non-smokers with periodontitis, and 18 periodontally healthy subjects were included in the study. Periodontal clinical indexes were recorded and the levels of IL-17 and IL-35 in saliva and GCF were analyzed. No significant difference was detected among the groups in terms of salivary IL-17 and IL-35 levels. GCF IL-17 and IL-35 concentration levels in the non-smoker periodontitis group were significantly lower than the others (p < 0.05). Total levels of GCF IL-17 were significantly higher in both periodontitis groups than the control group; and total levels of GCF IL-35 were significantly higher in non-smoker periodontitis group than the others (p < 0.05). A positive correlation was detected between the salivary IL-17 and IL-35 levels (r = 0.884), GCF IL-17 and IL-35 concentrations (r = 0.854), and total GCF IL-17 and IL-35 (r = 0.973) levels (p < 0.01). The present study revealed a positive correlation between the IL-35 and IL-17 levels both in saliva and GCF. IL-17 and IL-35 can be considered as one of the cytokines that play a role in periodontal health and periodontitis; and smoking may be among the factors that affect the levels of these cytokines in GCF and saliva.

Interleukin-12: Structure, Function, and Its Impact in Colorectal Cancer

Interleukin 12 (IL-12) is a heterodimer consisting of 2 subunits, p35 and p40, with unique associations and interacting functions with its family members. IL-12 is one of the most important cytokines regulating the immune system response and is integral to adaptive immunity. IL-12 has shown marked therapeutic potential in a variety of tumor types. This review therefore summarizes the characteristics of IL-12 and its application in tumor treatment, focusing on its antitumor effects in colorectal cancer (CRC) and potential radiosensitization mechanisms. We aim to provide a current reference for IL-12 and other potential CRC treatment strategies.

Interleukin-35 protein inhibits osteoclastogenesis and attenuates collagen-induced arthritis in mice

Rheumatoid arthritis (RA) is a chronic autoimmune disease. Its pathological features include synovial inflammation, bone erosion, and joint structural damage. Our previous studies have shown that interleukin (IL)-35 is involved in the pathogenesis of bone loss in RA patients. In this study, we are further evaluating the efficacy of IL-35 on collagen-induced arthritis (CIA) in the mouse model. Male DBA/1J mice (n = 10) were initially immunized, 2 μg/mouse IL-35 was injected intraperitoneally every week for 3 weeks after the establishment of the CIA model. Clinical arthritis, histopathological analysis, and three-dimensional micro-computed tomography (3D micro-CT) were determined after the mice were anesthetized on the 42th day. In vitro, RANKL/M-CSF induced mouse preosteoclasts (RAW264.7 cells line) was subjected to antiarthritis mechanism study in the presence of IL-35. The results of clinical arthritis, histopathological analysis, and 3D micro-CT, the expression of RANK/RANKL/OPG axis, inflammatory cytokines, and osteoclastogenesis-related makers demonstrated decreasing severity of synovitis and bone destruction in the ankle joints after IL-35 treatment. Furthermore, IL-35 attenuated inflammatory cytokine production and the expression of osteoclastogenesis-related makers in a mouse preosteoclasts cell line RAW264.7. The osteoclastogenesis-related makers were significantly reduced in IL-35 treated RAW264.7 cells line after blockage with the JAK/STAT1 signaling pathway. These results demonstrated that IL-35 protein could inhibits osteoclastogenesis and attenuates CIA in mice. We concluded that IL-35 can exhibit anti-osteoclastogenesis effects by reducing the expression of inflammatory cytokines and osteoclastogenesis-related makers, thus alleviating bone destruction in the ankle joint and could be a potential therapeutic target for RA.

Immunomodulatory effects of iTr35 cell subpopulation and its research progress

The spotlight in recent years has increasingly focused on inducible regulatory T cells 35 (iTr35), a novel subpopulation of regulatory T cells characterized by phenotypic stability, heightened reactivity, and potent immunosuppressive function through the production of IL-35. Despite being in the exploratory phase, research on iTr35 has garnered significant interest. In this review, we aim to consolidate our understanding of the biological characteristics and immunomodulatory mechanisms of iTr35, offering fresh perspectives that may pave the way for its potential applications in disease diagnosis and treatment.

Mechanisms underlying immunosuppression by regulatory cells

Regulatory cells, such as regulatory T cells (Tregs), regulatory B cells (Bregs), and myeloid-derived suppressor cells (MDSCs), play a crucial role in preserving immune tolerance and controlling immune responses during infections to prevent excessive immune activation. However, pathogens have developed strategies to hijack these regulatory cells to decrease the overall effectiveness of the immune response and persist within the host. Consequently, therapeutic targeting of these immunosuppressive mechanisms during infection can reinvigorate the immune response and improve the infection outcome. The suppressive mechanisms of regulatory cells are not only numerous but also redundant, reflecting the complexity of the regulatory network in modulating the immune responses. The context of the immune response, such as the type of pathogen or tissue involved, further influences the regulatory mechanisms involved. Examples of these immunosuppressive mechanisms include the production of inhibitory cytokines such as interleukin 10 (IL-10) and transforming growth factor beta (TGF-β) that inhibit the production of pro-inflammatory cytokines and dampen the activation and proliferation of effector T cells. In addition, regulatory cells utilize inhibitory receptors like cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1) to engage with their respective effector cells, thereby suppressing their function. An alternative approach involves the modulation of metabolic reprogramming in effector immune cells to limit their activation and proliferation. In this review, we provide an overview of the major mechanisms mediating the immunosuppressive effect of the different regulatory cell subsets in the context of infection.

IL-35: New Target for Immunotherapy Targeting the Tumor Microenvironment

Interleukin 35(IL-35) is a newly discovered inhibitory cytokine of the IL12 family. More recently, IL-35 was found to be increased in the tumor microenvironment (TME) and peripheral blood of many patients with cancer, indicating that it plays an important role in the TME. Tumors secrete cytokines that recruit myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Treg) into the TME to promote malignant progression, which is a great challenge for cancer treatment. Radiotherapy causes serious adverse effects, and tumor resistance to immune checkpoint inhibitors is still an unsolved challenge. Thus, new cancer therapy approaches are urgently needed. Numerous studies have shown that IL-35 can recruit immunosuppressive cells to enable tumor immune escape by promoting the conversion of immune cells into a tumor growth-promoting phenotype as well as facilitating tumor angiogenesis. IL-35-neutralizing antibodies were found to boost the chemotherapeutic effect of gemcitabine and considerably reduce the microvascular density of pancreatic cancer in mice. Therefore, targeting IL-35 in the TME provides a promising cancer treatment target. In addition, IL-35 may be used as an independent prognostic factor for some tumors in the near future. This review intends to reveal the interplay of IL-35 with immune cells in the TME, which may provide new options for the treatment of cancer.

The dichotomic role of single cytokines: Fine-tuning immune responses

Cytokines are known for their pleiotropic effects. They can be classified by their function as pro-inflammatory, such as tumor necrosis factor (TNF), interleukin (IL) 1 and IL-12, or anti-inflammatory, like IL-10, IL-35 and transforming growth factor β (TGF-β). Though this type of classification is an important simplification for the understanding of the general cytokine's role, it can be misleading. Here, we discuss recent studies that show a dichotomic role of the so-called pro and anti-inflammatory cytokines, highlighting that their function can be dependent on the microenvironment and their concentrations. Furthermore, we discuss how the back-and-forth interplay between cytokines and immunometabolism can influence the dichotomic role of inflammatory responses as an important target to complement cytokine-based therapies.

Regulatory B cells induced by interleukin-35 inhibit inflammation and alveolar bone resorption in ligature-induced periodontitis

BACKGROUND

Regulatory B cells (Bregs) have been reported to suppress immune responses and alveolar bone loss in murine periodontitis models. These cells could be induced by interleukin (IL)-35 which is increased upon periodontal inflammation. Thus, this study aimed to explore the role of Bregs induced by IL-35 in periodontitis.

METHODS

Experimental periodontitis was induced in mice by ligature. Two weeks after ligation, the test group was systemically treated with IL-35 for 1 week. Four weeks after ligation, all mice were euthanized, and alveolar bone loss was evaluated by microcomputed tomography. Cytokines associated with periodontitis were analyzed using reverse transcription-quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. Bregs in spleens, cervical lymph nodes, and periodontal tissues were detected by flow cytometry and immunofluorescence staining.

RESULTS

In the mouse model of periodontitis, IL-35 induced the expansion of CD1dhi CD5+ B10 cells with increased interleukin-10 (IL-10) and IL-35 production. IL-35 administration also attenuated alveolar bone loss and reduced the levels of proinflammatory cytokines in situ.

CONCLUSIONS

Following ligature-induced periodontitis in mice, IL-35 inhibited periodontal inflammation and alveolar bone resorption at least partially through the induction of B10 cells and IL-35+ Bregs.

Regulatory T cells in lung disease and transplantation

Pulmonary disease can refer to the disease of the lung itself or the pulmonary manifestations of systemic diseases, which are often connected to the malfunction of the immune system. Regulatory T (Treg) cells have been shown to be important in maintaining immune homeostasis and preventing inflammatory damage, including lung diseases. Given the increasing amount of evidence linking Treg cells to various pulmonary conditions, Treg cells might serve as a therapeutic strategy for the treatment of lung diseases and potentially promote lung transplant tolerance. The most potent and well-defined Treg cells are Foxp3-expressing CD4+ Treg cells, which contribute to the prevention of autoimmune lung diseases and the promotion of lung transplant rejection. The protective mechanisms of Treg cells in lung disease and transplantation involve multiple immune suppression mechanisms. This review summarizes the development, phenotype and function of CD4+Foxp3+ Treg cells. Then, we focus on the therapeutic potential of Treg cells in preventing lung disease and limiting lung transplant rejection. Furthermore, we discussed the possibility of Treg cell utilization in clinical applications. This will provide an overview of current research advances in Treg cells and their relevant application in clinics.

The role of iTr35 cells in the inflammatory response and fibrosis progression of systemic sclerosis

OBJECTIVE

To evaluate the role of induced immunosuppressive T regulatory (iTr) 35 cells in SSc-related inflammation and fibrosis.

METHODS

Sixty-eight SSc patients were enrolled in this study. Subsets of iTr35 and Tr1 were measured by flow cytometry. IL-35 and IL-10 levels were measured using ELISA. Expressions of iTr35, Tr1, fibrosis-related genes and proteins associated with signalling pathways were determined using immunofluorescence, western blot and immunohistochemistry assays.

RESULTS

In peripheral blood, the proportions of the iTr35 cells were higher and Tr1 cells were lower than the control group. Similarly, IL-35 expression was increased, while IL-10 levels were decreased. In fibroblasts from skin tissue, the expression levels of EBI3, IL-12Ap35, Foxp3 and IL-10 were decreased, but collagen I, TGF-β, alpha smooth muscle actin (α-SMA) and fibronectin levels were increased. Phosphorylated STAT3/6 were increased, but iTr35 and Tr1 cell levels were significantly decreased. When CD4+ cells were incubated with both recombinant human (rh)IL-35 and rhIL-10, the cell numbers of iTr35 and Tr1 were greater than the same type of cells treated with rhIL-35 or rhIL-10 alone. However, the viability of conventional CD4+ T cells was decreased by gradually increasing iTr35 cells. Moreover, iTr35 cells affected α-SMA expression through the STAT3/6 signalling pathway.

CONCLUSION

Both iTr35 and Tr1 cells are involved in SSc-related inflammation and fibrosis. IL-35 can induce iTr35 cells, showing a synergistic effect with IL-10. We also found that iTr35 cells can inhibit T cell proliferation and differentiation via the STAT3/6 signalling pathway, thereby causing fibrosis.

Ebi3 knockout aggravates experimental periodontitis via Th17 polarization

AIM

To investigate the role of Ebi3-related cytokines (i.e., interleukin [IL]-35 and/or IL-27) in experimental periodontitis using Ebi3 knockout (KO) mice.

MATERIALS AND METHODS

The maxillary right second molar teeth of Ebi3 KO mice and C57BL/6 mice were tied with a silk ligature to induce periodontitis. Three days after ligation, gingival tissues were collected for gene expression analyses. Five days after ligation, the maxillae were removed for haematoxylin and eosin staining and immunohistochemistry. Seven days after ligation, the maxillae were removed for micro-computed tomography.

RESULTS

The ligated side of Ebi3 KO mice showed intense alveolar bone resorption, which was substantially more pronounced than in wild-type (WT) mice. IL-17A expression was significantly higher in the gingiva of the ligated side of Ebi3 KO mice compared with WT mice. IL-10 expression was significantly lower in Ebi3 KO mice than in WT mice. The ligature-induced alveolar bone resorption in Ebi3 KO mice that received recombinant IL-35 injection was significantly less compared with that in Ebi3 KO mice that received control injection.

CONCLUSIONS

Together, these findings suggest that Th17 cells exacerbate experimental periodontitis in mice lacking Ebi3 and that IL-35 may play a critical role in inhibiting periodontal tissue destruction.

Tregs in transplantation tolerance: role and therapeutic potential

CD4+ Foxp3+ regulatory T cells (Tregs) are indispensable for preventing autoimmunity, and they play a role in cancer and transplantation settings by restraining immune responses. In this review, we describe evidence for the importance of Tregs in the induction versus maintenance of transplantation tolerance, discussing insights into mechanisms of Treg control of the alloimmune response. Further, we address the therapeutic potential of Tregs as a clinical intervention after transplantation, highlighting engineered CAR-Tregs as well as expansion of donor and host Tregs.

Suppression of Experimental Autoimmune Encephalomyelitis in Mice by β-Hydroxy β-Methylbutyrate, a Body-Building Supplement in Humans

Although several immunomodulatory drugs are available for multiple sclerosis (MS), most present significant side effects with long-term use. Therefore, delineation of nontoxic drugs for MS is an important area of research. β-Hydroxy β-methylbutyrate (HMB) is accessible in local GNC stores as a muscle-building supplement in humans. This study underlines the importance of HMB in suppressing clinical symptoms of experimental autoimmune encephalomyelitis (EAE) in mice, an animal model of MS. Dose-dependent study shows that oral HMB at a dose of 1 mg/kg body weight/d or higher significantly suppresses clinical symptoms of EAE in mice. Accordingly, orally administered HMB attenuated perivascular cuffing, preserved the integrity of the blood-brain barrier and blood-spinal cord barrier, inhibited inflammation, maintained the expression of myelin genes, and blocked demyelination in the spinal cord of EAE mice. From the immunomodulatory side, HMB protected regulatory T cells and suppressed Th1 and Th17 biasness. Using peroxisome proliferator-activated receptor (PPAR)α-/- and PPARβ-/- mice, we observed that HMB required PPARβ, but not PPARα, to exhibit immunomodulation and suppress EAE. Interestingly, HMB reduced the production of NO via PPARβ to protect regulatory T cells. These results describe a novel anti-autoimmune property of HMB that may be beneficial in the treatment of MS and other autoimmune disorders.

Impaired Regulation by IL-35 in Systemic Sclerosis

This study investigated the role of IL-35 in systemic sclerosis (SSc) patients, focusing on CD4+ T cell response and immunomodulatory cytokine production. By comparing the cytokine levels in healthy donors (HD) and SSc patients using ELISAs, we found a significantly lower plasma IL-35 concentration in the SSc patients (52.1 ± 5.6 vs. 143 ± 11.1, p < 0.001). Notably, the IL-35 levels showed a negative correlation with TGF-β (p < 0.001) and IL-17 (p = 0.04). Assessing the IL-35R expression across cell types in the SSc patients and HDs via flow cytometry, we found higher levels on monocytes (40.7 + 5.7 vs. 20.3 ± 1.9, p < 0.001) and lower levels on CD8+ T cells (61.8 ± 9.2 vs. 83.4 ± 0.8, p < 0.05) in the SSc patients. The addition of recombinant IL-35 to stimulated peripheral blood mononuclear cells reduced the IL-17+CD4+ T cell percentage (9.0 ± 1.5 vs. 4.8 ± 0.7, p < 0.05) and increased the IL-35+CD4+ T percentage (4.1 ± 2.3 vs. 10.2 ± 0.8, p < 0.001). In a Treg:Tresponder cell Sco-culture assay with HD and SSc samples, rIL35 decreased the cell proliferation and levels of IL-17A (178.2 ± 30.5 pg/mL vs. 37.4 ± 6.4 pg/mL, p < 0.001) and TGF-β (4194 ± 777 pg/mL vs. 2413 ± 608 pg/mL, p < 0.01). Furthermore, we observed a positive correlation between the modified Rodnan skin score (mRSS) and TGF-β (p < 0.001), while there was a negative correlation between mRSS and IL-35 (p = 0.004). Interestingly, higher levels of plasmatic IL-35 were detected in individuals with limited disease compared to those with diffuse disease (60.1 ± 8.0 vs. 832.3 ± 4.1, p < 0.05). These findings suggest that IL-35 exhibits anti-inflammatory properties in SSc and it may serve as a marker for disease severity and a therapeutic target.

Murine Placental Erythroid Cells Are Mainly Represented by CD45+ Immunosuppressive Erythroid Cells and Secrete CXCL1, CCL2, CCL3 and CCL4 Chemokines

Erythroid cells are emerging players in immunological regulation that have recently been shown to play a crucial role in fetomaternal tolerance in mice. In this work, we set ourselves the goal of discovering additional information about the molecular mechanisms of this process. We used flow cytometry to study placental erythroid cells' composition and BioPlex for the secretome profiling of 23 cytokines at E12.5 and E19.5 in both allogeneic and syngeneic pregnancies. We found that (1) placental erythroid cells are mainly represented by CD45⁺ erythroid cells; (2) the secretomes of CD71⁺ placental erythroid cells differ from the ones in syngeneic pregnancy; (3) CCL2, CCL3, CCL4 and CXCL1 chemokines were secreted on each day of embryonic development and in both types of pregnancy studied. We believe that these chemokines lure placental immune cells towards erythroid cells so that erythroid cells can induce anergy in those immune cells via cell-bound ligands such as PD-L1, enzymes such as ARG1, and secreted factors such as TGFβ-1.

Interleukin-35 Enhances Regulatory T Cell Function by Potentially Suppressing Their Transdifferentiation into a T Helper 17-Like Phenotype in Kawasaki Disease

Interleukin-35 (IL-35) modulates immune cell activity in inflammation and autoimmune disorders. However, its specific effects on regulatory T cells (Tregs) in Kawasaki disease remain ambiguous. We enrolled 37 patients with Kawasaki disease and 20 healthy controls in this study. The percentages of CD4⁺CD25⁺CD127^dim/- Tregs and CD4⁺IL-17A⁺ T helper 17 (Th17) cells were determined via flow cytometry. Tregs were enriched and stimulated by recombinant IL-35. Immunosuppressive activity of Tregs was via co-culture with autologous CD4⁺CD25^- T cells. Purified Tregs were cultured for Th17 polarization, and the influence of IL-35 on Tregs transdifferentiation into a Th17-like phenotype was determined. The percentage of Tregs was elevated in patients with Kawasaki disease and positively correlated with C-reactive protein levels. There was no significant difference in the percentage of Th17 cells between the two groups. IL-35 stimulation increased the percentage of Tregs in both groups, but decreased the percentage of Tregs Th17 cells in affected patients. IL-35 enhanced the immunosuppressive activity of Tregs in both groups, resulting in decreased cellular proliferation and increased IL-35 subunit mRNA relative levels in co-culture system. IL-35 did not affect the immune checkpoint molecule expression in Tregs, but inhibited the transdifferentiation of Tregs into a Th17-like phenotype in affected patients, indicating by the down-regulations of C-C motif chemokine receptor-4/6 expression, retinoid-related orphan nuclear receptor γt mRNA levels, and IL-17 secretion. IL-35 contributes to the immunosuppressive function of Tregs by inhibiting the cellular proliferation and transdifferentiation of Tregs into a Th17-like phenotype, which may be a protective mechanism against Kawasaki disease.

Peripheral blood subpopulations of Bregs producing IL-35 in women with endometriosis

PROBLEM

Interleukin 35 (IL-35) is involved in the pathogenesis of endometriosis by suppressing immunoreaction and promoting endometrial cell proliferation. It may also be an essential cytokine in forming the immunosuppressive functions of regulatory B lymphocytes (Bregs). The involvement of Bregs in the pathogenesis of endometriosis has not been previously investigated. In this study, we determined the frequencies of different Breg subpopulations, namely, B10, immature B-cells, and plasmablasts, and their abilities to produce IL-35 in women with endometriosis compared to healthy women.

METHODS

The frequencies of different subpopulations of Bregs producing IL-35 were measured in the peripheral blood of women with endometriosis (total pool), women with deep infiltration endometriosis (DIE), women with ovarian endometriosis, and healthy women as a control by flow cytometry.

RESULTS

We observed a decrease in the percentage of B10 cells and plasmablasts in women with endometriosis and an increase in the percentage of these Breg populations producing IL-35 in the same experimental group. Interestingly, we also revealed that women with DIE had increased percentages of B10 cells and plasmablasts producing IL-35.

CONCLUSION

Taken together, our findings are the first to reveal the frequencies of different subpopulations of Bregs producing IL-35 in women with endometriosis. The results suggest that IL-35 expression in B lymphocytes could be used as a peripheral marker of endometriosis; however, further studies are needed.

TNFR2+ regulatory T cells protect against bacteremic pneumococcal pneumonia by suppressing IL-17A-producing γδ T cells in the lung

Streptococcus pneumoniae is a pathogen of global morbidity and mortality. Pneumococcal pneumonia can lead to systemic infections associated with high rates of mortality. We find that, upon pneumococcal infection, pulmonary Treg cells are activated and have upregulated TNFR2 expression. TNFR2-deficient mice have compromised Treg cell responses and highly activated IL-17A-producing γδ T cell (γδT17) responses, resulting in significantly enhanced neutrophil infiltration, tissue damage, and rapid development of bacteremia, mirroring responses in Treg cell-depleted mice. Deletion of total Treg cells predominantly activate IFNγ-T cell responses, whereas adoptive transfer of TNFR2+ Treg cells specifically suppress the γδT17 response, suggesting a targeted control of γδT17 activation by TNFR2+ Treg cells. Blocking IL-17A at early stage of infection significantly reduces bacterial blood dissemination and improves survival in TNFR2-deficient mice. Our results demonstrate that TNFR2 is critical for Treg cell-mediated regulation of pulmonary γδT17-neutrophil axis, with impaired TNFR2+ Treg cell responses increasing susceptibility to disease.

INTERLEUKIN-35 DOWNREGULATES THE IMMUNE RESPONSE OF EFFECTOR CD4 + T CELLS VIA RESTRICTING HIGH MOBILITY GROUP BOX-1 PROTEIN-DEPENDENT AUTOPHAGY IN SEPSIS

ABSTRACT

Background: Immunosuppression is critically involved in the development of sepsis and is closely associated with poor outcomes. The novel role of the anti-inflammatory cytokine IL-35 in sepsis was examined. Methods: Sepsis was induced by in C57BL/6 mice cecal ligation and puncture (CLP). The impacts of IL-35 on effector CD4 + T cells were investigated by examining cell proliferation and the Th1/Th2 ratio in the presence of recombinant IL-35 (rIL-35) or anti-IL-35 (EBI3). The regulatory effect of IL-35 on autophagy was evaluated by measuring autophagy markers and autophagic flux in CLP mice in vivo and in activated effector CD4 + T cells in vitro . Results: IL-35 levels were significantly increased in the serum and spleens of septic mice. rIL-35 administration after CLP further decreased proliferation and the Th1/Th2 ratio in effector CD4 + T cells and significantly shortened the survival time. Sepsis-induced autophagy activation was protective in effector CD4 + T cells and was blocked by rIL-35. The inhibitory effect of IL-35 on autophagy was observed in activated effector CD4 + T cells in vitro , and this effect was mediated by restricting high mobility group box-1 protein (HMGB1) translocation. Conclusion: IL-35 is an immunosuppressive cytokine that impairs CD4 + T-cell proliferation and differentiation in sepsis, and the effect might be mediated by reducing HMGB1-dependent autophagy.

Investigation of IL-35 and IL-39, New Members of the IL-12 Family, in Different Clinical Presentations of Brucellosis

Brucellosis is significantly influenced by the interactions between the causative Brucella bacteria and host immunity. Recently identified cytokines have been described for their immunomodulatory effects in numerous inflammatory, autoimmune and infectious diseases. Some of them are new members of cytokine superfamilies, including several members of the IL-12 superfamily (IL-35, IL-39). The major purpose of the present study was to investigate the role of these new immunomodulatory cytokines in Brucella infections. The levels of IL-35 and IL-39 in the serum of 40 acute and 40 chronic brucellosis patients and 40 healthy controls were measured by ELISA. The mRNA levels of IL-35 and IL-39 in PBMCs were detected by RT-qPCR. Both IL-35 and IL-39 serum concentrations were significantly higher in healthy control subjects than in brucellosis patients, and IL-35 and IL-39 serum levels of chronic brucellosis patients were higher than those of acute cases. It was also found that the expression of Ebi3/IL-12A (IL-35 genes) and Ebi3/IL-23A (IL-39 genes) was upregulated in chronic brucellosis patients compared to healthy controls. Moreover, the expression of the Ebi3/IL-12A and Ebi3/IL-23A genes was lower in patients with acute brucellosis than in patients with chronic brucellosis. Overall, this study showed that IL-35 and IL-39 are positively correlated in brucellosis and significantly decreased during the disease. Significantly lower levels of IL-35 and IL-39 in acute brucellosis than in chronic brucellosis and healthy controls suggest that these cytokines may play a key role in suppressing the immune response to brucellosis and its progression to chronicity.

Evaluation of gingival crevicular fluid interleukin-35 as a marker for identification of periodontal disease activity

BACKGROUND

This study was carried out to evaluate and compare the levels of IL-35 in gingival crevicular fluid (GCF) in periodontally healthy subjects, patients with gingivitis and chronic periodontitis and to assess IL-35 as a marker for identification of periodontal disease activity.

METHODS

GCF samples were obtained from periodontally healthy subjects (N.=15), gingivitis patients (N.=15) and patients with chronic periodontitis (N.=15). Clinical measurements like probing pocket depth, clinical attachment loss, bleeding on probing, Papillary Bleeding Index, and Modified Plaque Index were recorded. Enzyme-linked immunosorbent assay was used for the determination of GCF IL-35 levels in samples.

RESULTS

The IL-35 levels were significantly higher in the healthy subjects as compared to gingivitis and chronic periodontitis group. There was variation in GCF IL-35 levels in healthy sites in each group and gingivitis sites in gingivitis and chronic periodontitis patients.

CONCLUSIONS

The levels of IL-35 were observed to decrease with increase in the inflammatory status, so it might play a role in suppressing gingival inflammation and maintaining periodontal health.

Elevated expression of interleukin-27, IL-35, and decreased IL-12 in patients with thyroid-associated ophthalmopathy

PURPOSE

Thyroid-associated ophthalmopathy (TAO) is a chronic autoimmune disease. The interleukin-12 (IL-12) family includes IL-12, IL-23, IL-27, and IL-35, all of which play important roles in autoimmunity. Thus far, the relationship between IL-12, IL-27, and IL-35 and the TAO has not been evaluated.

METHODS

Seventy-five serum samples from patients with TAO were collected. Serum samples from 90 healthy controls (HC), 55 patients with Graves' disease (GD), 38 patients with uveitis (UV), 17 patients with Sjogren's syndrome (SS), and 65 patients with rheumatoid arthritis (RA) were collected as controls. The associations between IL-27, IL-35, IL-12, and other clinical parameters were analyzed.

RESULTS

Elevated serum levels of IL-27/IL-35 and decreased serum IL-12 levels were observed in TAO patients compared to those in HC (p < 0.001). For HC, we observed good diagnostic ability to predict TAO (area under the curve = 0.74, 0.78, and 0.78, for IL-27, IL-35, and IL-12, respectively). For other autoimmune diseases, IL-27, IL-35, and IL-12 had the ability to discriminate between UV, RA, and SS (area under the curve = 0.80, 0.83, and 0.85 for IL-27; 0.52, 0.69, and 0.67 for IL-35). The positive detection rates of IL-12 were significantly lower in the TAO group than in the UV and RA groups (p = 0.002, 0.01).

CONCLUSION

IL-12, IL-27, and IL-35 have the potential as biomarkers for TAO.

The Molecular Role of IL-35 in Non-Small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and a common cause of cancer-related death. Better understanding of the molecular mechanisms, pathogenesis, and treatment of NSCLC can help improve patient outcomes. Significant progress has been made in the treatment of NSCLC, and immunotherapy can prolong patient survival. However, the overall cure and survival rates are low, especially in patients with advanced metastases. Interleukin-35 (IL-35), an immunosuppressive factor, is associated with the onset and prognosis of various cancers. Studies have shown that IL-35 expression is elevated in NSCLC, and it is closely related to the progression and prognosis of NSCLC. However, there are few studies on the mechanism of IL-35 in NSCLC. This study discusses the role of IL-35 and its downstream signaling pathways in the pathogenesis of NSCLC and provides new insights into its therapeutic potential.

Suppressor CD4+ T cells expressing HLA-G are expanded in the peripheral blood from patients with acute decompensation of cirrhosis

OBJECTIVE

Identifying components of immuneparesis, a hallmark of chronic liver failure, is crucial for our understanding of complications in cirrhosis. Various suppressor CD4⁺ T cells have been established as potent inhibitors of systemic immune activation. Here, we establish the presence, regulation and mechanism of action of a suppressive CD4⁺ T cell subset expressing human leucocyte antigen G (HLA-G) in patients with acute decompensation of cirrhosis (AD).

DESIGN

Flow cytometry was used to determine the proportion and immunophenotype of CD4⁺HLA-G⁺ T cells from peripheral blood of 20 healthy controls (HCs) and 98 patients with cirrhosis (28 with stable cirrhosis (SC), 20 with chronic decompensated cirrhosis (CD) and 50 with AD). Transcriptional and functional signatures of cell-sorted CD4⁺HLA-G⁺ cells were delineated by NanoString technology and suppression assays, respectively. The role of immunosuppressive cytokine interleukin (IL)-35 in inducing this population was investigated through in vitro blockade experiments. Immunohistochemistry (IHC) and cultures of primary human Kupffer cells (KCs) were performed to assess cellular sources of IL-35. HLA-G-mediated T cell suppression was explored using neutralising antibodies targeting co-inhibitory pathways.

RESULTS

Patients with AD were distinguished by an expansion of a CD4⁺HLA-G⁺CTLA-4⁺IL-35⁺ immunosuppressive population associated with disease severity, clinical course of AD, infectious complications and poor outcome. Transcriptomic analyses excluded the possibility that these were thymic-derived regulatory T cells. IHC analyses and in vitro cultures demonstrate that KCs represent a potent source of IL-35 which can induce the observed HLA-G⁺ phenotype. These exert cytotoxic T lymphocyte antigen-4-mediated impaired responses in T cells paralleled by an HLA-G-driven downregulation of T helper 17-related cytokines.

CONCLUSION

We have identified a cytokine-driven peripherally derived suppressive population that may contribute to immuneparesis in AD.

At Embryo Implantation Site IL-35 Secreted by Trophoblast, Polarizing T Cells towards IL-35+ IL-10+ IL-4+ Th2-Type Cells, Could Favour Fetal Allograft Tolerance and Pregnancy Success

We investigated the role of rhIL-35, at low concentrations compatible with those produced by human trophoblast cells (less than 1 ng/mL), on human T helper (Th) cell functions and the presence of decidual IL-35-producing Th cells in human pregnancy. We found that human trophoblast cells produced IL-35 but not IL-4 or IL-10. RhIL-35, at concentrations produced by human trophoblasts, polarized T cells towards IL-35+, IL-10+, IL-4+ Th2-type cells and to Foxp3+ EBI3+ p35+ T reg cells producing IL-35 but not IL-10 and IL-4. Moreover, rhIL-35 at low concentrations did not suppress the proliferation of Th cells but stimulated IL-4 and IL-10 production by established Th clones. In particular, Th1-type clones acquired the capacity to produce IL-4. In addition, purified human trophoblast cell supernatants containing IL-35 upregulated IL-4 and IL-10 production by Th clones. Finally, IL-35+, IL-10+, IL-4+ Th2-type cells, which were found to be induced by low concentrations of IL-35 compatible with those produced by human trophoblasts, are exclusively present in the decidua of a successful pregnancy and at the embryo implantation site, suggesting their stringent dependence on trophoblast cells. Thus, the proximity of Th cells to IL-35-producing trophoblasts could be the determining factor for the differentiation of IL-35+, IL-10+, IL-4+ Th2-type cells that are crucial for human pregnancy success.

Interleukin-35 promotes Breg expansion and interleukin-10 production in CD19+ B cells in patients with ankylosing spondylitis

OBJECTIVE

IL-35 is a potent immunosuppressive and anti-inflammatory cytokine, consisting of a p35 subunit and an Epstein-Barr virus-induced gene 3 (EBI3) subunit, which suppresses CD4⁺ effector T cell proliferation and promotes regulatory T cell (Treg) expansion. However, the effects of IL-35 on regulatory B cells (Bregs) in ankylosing spondylitis (AS) have not been explored. The present study aimed (i) to measure serum IL-35 levels and the percentages of Bregs in the peripheral blood of patients with AS and (ii) to explore their relationships in the pathogenesis of AS.

METHODS

A total of 77 patients with AS (AS group), including 47 inactive AS and 30 active AS cases, and 59 healthy controls (HCs) were enrolled into this study. The serum levels of IL-35 and IL-10 were detected by ELISA, and the mRNA levels of p35 and EBI3 were measured by RT-qPCR. The percentages of CD19⁺CD24^hiCD38^hi and CD19⁺CD24^hiCD27⁺ Bregs and IL-35 receptor (IL-12Rβ2, IL-27Rα and gp130), IL-10, p-STAT1, p-STAT3, and p-STAT4 in CD19⁺ B cells were detected by flow cytometry. The correlations between IL-35 levels and percentages of Bregs were analyzed by determining Pearson's correlation coefficient. The effect of IL-35 on Bregs was determined by mix-culture of recombinant (r) IL-35 with peripheral blood mononuclear cells (PBMCs).

RESULTS

The serum IL-35 and IL-10 levels, p35 and EBI3 mRNA levels, and the percentages of CD19⁺CD24^hiCD38^hi and CD19⁺CD24^hiCD27⁺ Bregs were significantly lower in AS patients than those in HCs. In addition, the percentages of CD19⁺CD24^hiCD38^hi and CD19⁺CD24^hiCD27⁺ Bregs in active AS patients were significantly lower than those in inactive AS patients. The serum IL-35 levels were positively correlated with the percentages of CD19⁺CD24^hiCD38^hi and CD19⁺CD24^hiCD27⁺ Bregs in AS patients. IL-12Rβ2 and IL-27Rα, but not gp130 subunit, were expressed in CD19⁺ B cells in AS patients. RIL-35 could effectively promote CD19⁺CD24^hiCD38^hi Breg expansion and IL-10 production. Meanwhile, rIL-35 also promoted the expression of IL-12Rβ2 and IL-27Rα and the phosphorylation of STAT1 and STAT3 in CD19⁺ B cells.

CONCLUSION

These results demonstrated that reduced IL-35 production may be associated with Bregs defects in AS patients. RIL-35 induced the proliferation of CD19⁺CD24^hiCD38^hi Bregs and IL-10 production, suggesting that IL-35 may serve as a reference for further investigation to develop novel treatments for AS. Key Points • Our study investigated the effects of IL-35 on Bregs in AS patients. • We found the serum IL-35, IL-10 levels, and the percentages of CD19⁺CD24^hiCD38^hi and CD19⁺CD24^hiCD27⁺ Bregs were significantly lower in AS patients. • The serum IL-35 levels were positively correlated with the percentages of CD19⁺CD24^hiCD38^hi and CD19⁺CD24^hiCD27⁺ Bregs in AS patients. • Recombinant IL-35 could effectively promote CD19⁺CD24^hiCD38^hi Breg expansion and IL-10 production.

Association of Elevated Expression Levels of COL4A1 in Stromal Cells with an Immunosuppressive Tumor Microenvironment in Low-Grade Glioma, Pancreatic Adenocarcinoma, Skin Cutaneous Melanoma, and Stomach Adenocarcinoma

Aberrant expression of collagen type IV alpha chain 1 (COL4A1) can influence tumor cell behavior. To examine the association of COL4A1 expression in the tumor microenvironment (TME) with tumor progression, we performed bioinformatics analyses of The Cancer Genome Atlas RNA sequencing and RNA microarray datasets available in public databases and identified upregulated COL4A1 expression in most examined tumor types compared to their normal counterparts. The elevated expression of COL4A1 was correlated with low survival rates of patients with low-grade glioma, pancreatic adenocarcinoma, skin cutaneous melanoma, and stomach adenocarcinoma, thus suggesting its potential use as a biomarker for the poor prognosis of these tumors. However, COL4A1 was mostly expressed in adjacent stromal cells, such as cancer-associated fibroblasts (CAFs) and endothelial cells. Additionally, COL4A1 expression was highly correlated with the signatures of CAFs and endothelial cells in all four tumor types. The expression of marker genes for the infiltration of pro-tumoral immune cells, such as Treg, M2, and TAM, and those of immunosuppressive cytokines exhibited very strong positive correlations with COL4A1 expression. Collectively, our data suggest that COL4A1 overexpression in stromal cells may be a potential regulator of tumor-supporting TME composition associated with poor prognosis.

Pentosan Polysulfate Sodium augments the therapeutic effect of 5-Aminosalicylic Acid in DSS colitis model; the role of IL-35 expression

Ulcerative colitis (UC) primarily affects the mucosa of the distal colon. Dysregulated immune response in genetically-prone persons is claimed to be responsible for chronic intestinal inflammation. This study aimed to explore the efficacy and the hematological effects of pentosan polysulfate sodium (PPS) in a dextran sulfate sodium (DSS)-induced colitis model. Forty C57BL/6 female mice were equally divided into five groups: control group, DSS-colitis group, DSS-colitis treated with 5-aminosalicylic acid, DSS-colitis treated with PPS, and DSS-colitis treated with both drugs. Disease activity index (DAI) and colon length were calculated. Colonic IL-6 and IL-35 levels were assayed by ELISA. IL-35 gene expression was evaluated by qRT-PCR. Colon tissue samples were examined by H&E stain and immunohistochemistry (IHC) of Ki67. The colitis group subjected to combined treatment showed the best outcome with significant improvement of DAI and increased colon length. Colonic IL-6 was significantly lower in both PPS- and combination-treated groups accompanied by a significantly higher IL-35 level and its EBI3 subunit mRNA expression. However, the PPS-treated colitis group showed higher gene expression of IL-35 EBI3 subunit by 1.5-fold compared with the combined group. The colon mucosa and crypts were significantly preserved in mice treated with both drugs with the best Ki67 positive cell density. PPS is a safe and promising drug in the treatment of UC as it exerted the best positive effect on the anti-inflammatory IL-35 level and gene expression. However, superior improvement of DAI was seen when PPS was added to ASA with a greater mucosal proliferation and repair.

Effect of IL-35 on apoptosis, adhesion, migration, and activation of eosinophils in allergic rhinitis

BACKGROUND

Eosinophils play critical roles in the development of allergic rhinitis (AR) by releasing toxic substance. Interleukin-35 (IL-35), a newly identified anti-inflammatory cytokine, had potent inhibitive role for eosinophil infiltration in allergic disease. However, the direct effect of IL-35 on eosinophil was not clear.

METHODS

Twenty AR children and sixteen controls were recruited. The correlation between IL-35 protein expression and blood eosinophil counts and activation was analyzed. The effect of IL-35 on eosinophil apoptosis and adhesion was analyzed by flow cytometry. Transwell system was used for the migration assay. The eosinophil cationic protein (ECP) from supernatant of eosinophils after IL-35 stimulation was detected by enzyme-linked immunosorbent assay kits.

RESULTS

The IL-35 protein levels were negatively correlated with eosinophil counts (p < .01) and ECP concentration (p < .01) in AR children. IL-35 promotes apoptosis and inhibits adhesion, migration, and activation of eosinophils. Moreover, the mRNA expression of IL-12 receptor β2 and glycoprotein 130 were significantly enhanced by eosinophils after IL-35 stimulation. The apoptosis induced by IL-35 was mediated by phosphoinositide 3-kinase (PI3K) pathway. IL-35 inhibits adhesion of eosinophils through extracellular regulated protein kinases (ERK) and PI3K pathways. The eosinophil chemotaxis and activation affected by IL-35 were mediated by PI3K and p38 mitogen-activated protein kinase (MAPK) pathways.

CONCLUSION

Our results confirmed that IL-35 played inhibitive roles in apoptosis, adhesion, migration, and activation of eosinophils in AR, implying that IL-35 may be used as treatment target in future.

Interleukin 35 contributes to immunosuppression by regulating inflammatory cytokines and T cell populations in the acute phase of sepsis

Cytokines interact closely with each other and play a crucial role in the progression of sepsis. We focused on the associations of a cytokine network with IL-35 in sepsis. First, the retrospective study included 42 patients with sepsis and 23 healthy controls. Blood samples were collected from patients on days 1, 2, 4. Levels of IL-35, IL-1β, IL-4, IL-6, IL-10, IL-17A, TNF-α and IFN-γ were measured. They all increased to various extend on days 1, 2, 4, and strongly associated with markers of disease severity. Network analysis revealed a network formed by IL-35, with IL-6, IL-10, IL-17A, TNF-α and IFN-γ throughout the acute phase of sepsis(days 1, 2 and4). Then, the CLP-induced septic rats were used. The recombinant human IL-35(rIL-35) upregulated the levels of IL-10, but downregulated IL-4, IL-6, IL-17A, TNF-α and IFN-γ, while it had no significant effect on IL-1β, and upregulated the percentages of CD4⁺CD25⁺Tregs, and iTR35, but downregulated Teff cells in the peripheral blood. The rIL-35 reduced inflammation damage and improved prognosis of the septic rats. IL-35 forms a network with other cytokines and plays a major role in the immunopathogenesis of sepsis.

Endocrine disorders and fertility and pregnancy: An update

It is estimated that more and more couples suffer from fertility and pregnancy maintenance disorders. It is associated with impaired androgen secretion, which is influenced by many factors, ranging from genetic to environmental. It is also important to remember that fertility disorders can also result from abnormal anatomy of the reproductive male and female organ (congenital uterine anomalies - septate, unicornuate, bicornuate uterus; acquired defects of the uterus structure - fibroids, polyps, hypertrophy), disturbed hormonal cycle and obstruction of the fallopian tubes resulting from the presence of adhesions due to inflammation, endometriosis, and surgery, abnormal rhythm of menstrual bleeding, the abnormal concentration of hormones. There are many relationships between the endocrine organs, leading to a chain reaction when one of them fails to function properly. Conditions in which the immune system is involved, including infections and autoimmune diseases, also affect fertility. The form of treatment depends on infertility duration and the patient's age. It includes ovulation stimulation with clomiphene citrate or gonadotropins, metformin use, and weight loss interventions. Since so many different factors affect fertility, it is important to correctly diagnose what is causing the problem and to modify the treatment regimen if necessary. This review describes disturbances in the hormone secretion of individual endocrine organs in the context of fertility and the maintenance of pregnancy.

The Effects of Sishen Wan on T Cell Responses in Mice Models of Ulcerative Colitis Induced by Dextran Sodium Sulfate

Currently, it is unclear whether Sishen Wan (SSW) could modulate the balance of Th1 cells, Th17 cells, and Tregs and we evaluated the effects of SSW on T cell responses in mice models of ulcerative colitis (UC). The mice models of acute UC (4% dextran sodium sulfate (DSS), 8 days) and chronic UC (3% DSS, 16 days) with SSW were assayed. Colon tissues were collected for immunohistochemical analysis, enzyme linked immunosorbent assay (ELISA), and flow cytometry (FCM). The expressions of cytokines associated with Tregs, transcription factors of Th17 cells, the frequencies of Th1 cells, Th17 cells, and Tregs, and the functional plasticity of Th17 cells were detected. The frequency of IFN-γ⁺ T cells was not changed significantly with SSW treatment in acute DSS. In chronic models, the frequency of IFN-γ⁺ T cells was downregulated with SSW. Meanwhile, the levels of RORγt and the frequency of IL-17A⁺ Th17 cells showed no significant differences after SSW treatment. Despite no significant effect on the transdifferentiation of Th17 cells in chronic UC models, SSW transdifferentiated Th17 cells into IL-10⁺ Th17 cells and downregulated IFN-γ⁺ Th17 cells/IL-10⁺ Th17 cells in acute DSS. Moreover, there were no significant changes of cytokines secreted by Tregs in acute DSS after SSW treatment, but SSW facilitated the expressions of IL-10 and IL-35, as well as development of IL-10⁺ Tregs in chronic DSS. SSW showed depressive effects on the immunoreaction of Th17 cells and might promote the conversion of Th17 cells into IL-10⁺ Th17 cells in acute UC, while it inhibited the excessive reaction of Th1 cells, facilitated the development of Tregs, and enhanced the anti-inflammatory effects in chronic UC.

New progress in research of Th17 cells and related cytokines in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic non-specific intestinal inflammatory disease. IBD is an immune disease, and there is no cure for it at present. Intestinal immunity is the research focus of IBD. Focusing on Th17 cells and related cytokines, this article reviews the updated research on IBD, including its etiology, its relationship with adaptive immunity, and its relationship with Th17 cells. We also introduce Th17 cells and related cytokines, and their research in IBD. Finally, we point out the future research direction of Th17 cells in IBD.

Systemic Interleukins' Profile in Early and Advanced Colorectal Cancer

Tumor microenvironment (TME) is characterized by mutual interactions of the tumor, stromal and immune cells. Early and advanced colorectal tumors differ in structure and present altered serum cytokine levels. Mutual crosstalk among TME infiltrating cells may shift the balance into immune suppressive or pro-inflammatory, antitumor response this way influencing patients' prognosis. Cancer-related inflammation affects all the body and this way, the systemic level of cytokines could reflect TME processes. Despite numerous studies, it is still not known how systemic cytokines levels change during colorectal cancer (CRC) tumor development. Better understanding tumor microenvironment processes could help in planning therapeutic interventions and more accurate patient prognosis. To contribute to the comprehension of these processes within TME, we reviewed cytokines levels from clinical trials in early and advanced colorectal cancer. Presented data were analyzed in the context of experimental studies and studies analyzing tumor infiltration with immune cells. The review summarizes clinical data of cytokines secreted by tumor microenvironment cells: lymphocytes T helper 1 (Th1), lymphocytes T helper 2 (Th2), lymphocytes T helper 17 (Th17), regulatory T cells (Treg cells), regulatory T cells (Breg cells), M1/M2 macrophages, N1/N2 neutrophils, myeloid-derived suppressor cells (MDSC), dendritic cells (DC), innate lymphoid cells (ILC) natural killer (NK) cells and tumor cells.

Roles of IL-35-producing T and B cells in anti-acetylcholine receptor antibody-positive myasthenia gravis

BACKGROUND

Interleukin 35 (IL-35) plays an anti-inflammatory in numerous autoimmune diseases. However, the potential roles of IL-35-producing T and B cells and serum IL-35 levels in the pathogenesis of myasthenia gravis (MG) and its association with disease activity in patients with MG remain unclear.

METHODS

The percentages of IL-35-producing CD4 + CD25 + T cells and CD19 + B cells among peripheral blood mononuclear cells were determined in 37 patients with anti-acetylcholine receptor (AChR) antibody-positive MG and 35 healthy controls (HCs) by performing a flow cytometry analysis. Serum IL-35 levels in participants were determined using an enzyme-linked immunosorbent assay. Further, the correlations between IL35 levels and disease activity were analysed.

RESULTS

The percentages of IL-35-producing CD4 + CD25 + T cells and CD19 + B cells were significantly lower in patients with anti-AChR antibody-positive MG than in HCs (p = 0.001 and p = 0.002, respectively). Furthermore, patients with thymoma and patients with generalized MG had lower percentages of IL-35-producing CD4 + CD25 + T cells and CD19 + B cells than those without thymoma and those with ocular MG (p = 0.001 and p = 0.003; p = 0.008 and p = 0.001, respectively). Interestingly, the suppression of IL-35 secretion correlated negatively with the activities of daily living scores of patients with MG (r = -0.4774, p = 0.0028) and the quantitative MG scores (r = -0.4656, p = 0.0037). The proportions of IL-35-producing T cells and B cells and serum levels of IL-35 increased after treatment.

CONCLUSIONS

IL-35 may represent a potential biomarker for the clinical evaluation of MG.

The Effect of IL-35 on the Expression of Nasal Epithelial-Derived Proinflammatory Cytokines

Background

Airway epithelium plays an important role during the development of allergic rhinitis (AR), which is characterized by production of thymic stromal lymphopoietin (TSLP), interleukin 33 (IL-33), and interleukin 25 (IL-25). IL-35, mainly expressed by Treg cells, have negative regulation in Th2, Th17, and ILC2 inflammation. However, the effect of IL-35 on human nasal epithelial cells (HNECs) especially the secretion of nasal epithelial-derived proinflammatory cytokines as well as the possible mechanism is still unclear.

Methods

HNECs were cultured and stimulated by various stimulators. The expression of IL-33, IL-25, TSLP, eotaxin-1, eotaxin-2, and eotaxin-3 from supernatant was measured using real-time reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). AR mice were developed to verify the effect of IL-35 on nasal epithelial cells in vivo.

Results

After Poly I:C stimulation, IL-35 inhibited the production of IL-25, and TSLP from HNECs increased significantly compared with baseline levels (P < 0.05). After Dermatophagoides pteronyssinus or Aspergillus fumigatus stimulation, IL-35 inhibited the production of IL-25, IL-33, and TSLP from HNECs increased significantly compared with baseline levels (P < 0.05). After Dermatophagoides pteronyssinus, IL-35 inhibited the production of eotaxin-1, eotaxin-2, and eotaxin-3 released from HNECs increased significantly compared with baseline levels (P < 0.05). Similarly, IL-35-treated AR mice presented with decreased expression of IL-33, IL-25, TSLP, eotaxin-1, eotaxin-2, and eotaxin-3 in nasal lavage fluid.

Conclusion

IL-35 suppressed both type 2 inflammation-inducing cytokines and eosinophil chemotactic factor from HNECs, suggesting the important role of IL-35 during the development of AR.

Níveis de Interleucina-35 em Pacientes com Doença Arterial Coronariana Estável

Fundamento

Foi demonstrado que as subunidades de interleucina-35 (IL-35) estão fortemente expressas nas placas ateroscleróticas em humanos. Assim, considera-se que elas têm um papel na aterosclerose.

Objetivos

Neste estudo, os níveis de IL-35 foram comparados com o grupo controle em pacientes com doença arterial coronariana (DAC) estável, e a associação entre os níveis de IL-35 e o tipo, gravidade e extensão da lesão foram investigadas com o escore Gensini (GS) e o escore Syntax (SS) no grupo de pacientes

Métodos

Sessenta pacientes (18 mulheres e 42 homens) com DAC, diagnosticados por meio da angiografia coronária, que apresentaram dor no peito típica e teste de esforço não invasivo positivo, e 46 pacientes (18 mulheres e 28 homens) com luminograma normal, foram incluídos no estudo. Tanto o GS quanto o SS foram calculados para o grupo de pacientes, e esses valores foram comparados com os níveis de IL-35. Variáveis com distribuição não normal foram avaliadas com o teste U de Mann-Whitney, enquanto os parâmetros com distribuição normal foram analisados com o teste t de Student. A diferença entre as variáveis categóricas foi avaliada pelo teste de qui-quadrado ou de Fisher. Os valores de p<0,05 foram considerados como estatisticamente sinificativos.

Resultados

Não foram observadas diferenças significativas entre pacientes e o grupo controle em termos de características demográficas e achados laboratoriais. Em comparação ao grupo controle, os níveis de IL-35 no grupo com DAC foram consideravalmente menores (36,9±63,9 ng/ml vs. 33,2±13,2 ng/ml, p<0,008). Embora não tenha sido estatisticamente significativo, os níveis de IL-35 foram maiores em pacientes com SS mais baixo do que nos com SS mais alto (33,2±13,7 vs. 31,8±8,9, p=0,51). Os valores de IL-35 em pacientes com GS alto foram significativamente mais baixos do que em pacientes com GS baixo (35±17,4 vs. 30,7±8,6, p=0,043).

Conclusão

Demonstrou-se que os níveis de IL-35 podem ser um novo biomarcador para a DAC estável, e que a IL-35 está associada à extensão da DAC.

Interleukin-35 Prevents Development of Autoimmune Diabetes Possibly by Maintaining the Phenotype of Regulatory B Cells

The anti-inflammatory role of regulatory B cells (Breg cells) has been associated with IL-35 based on studies of experimental autoimmune uveitis and encephalitis. The role of Breg cells and IL-35⁺ Breg cells for type 1 diabetes (T1D) remains to be investigated. We studied PBMCs from T1D subjects and healthy controls (HC) and found lowered proportions of Breg cells and IL-35⁺ Breg cells in T1D. To elucidate the role of Breg cells, the lymphoid organs of two mouse models of T1D were examined. Lower proportions of Breg cells and IL-35⁺ Breg cells were found in the animal models of T1D compared with control mice. In addition, the systemic administration of recombinant mouse IL-35 prevented hyperglycemia after multiple low dose streptozotocin (MLDSTZ) injections and increased the proportions of Breg cells and IL-35⁺ Breg cells. A higher proportion of IFN-γ⁺ cells among Breg cells were found in the PBMCs of the T1D subjects. In the MLDSTZ mice, IL-35 administration decreased the proportions of IFN-γ⁺ cells among the Breg cells. Our data illustrate that Breg cells may play an important role in the development of T1D and that IL-35 treatment prevents the development of hyperglycemia by maintaining the phenotype of the Breg cells under an experimental T1D condition.

Comparison of FOXP3 and Interleukin 35 Expression Profiles in Kidney Transplant Recipients With Excellent Long-Term Graft Function and Acute Rejection

OBJECTIVES

Transplant tolerance is defined as graft acceptance without long-term use of immunosuppressive agents. Regulatory T cells are involved in the maintenance of peripheral self-tolerance by actively suppressing the activation and expansion of autoreactive T cells. In the present study, we compared the expression profiles of forkhead box protein P3 (FOXP3) and interleukin 35 in kidney transplant recipients who had excellent long-term graft function under immunosuppression versus recipients who had acute rejection.

MATERIALS AND METHODS

The 40 kidney transplant recipients included in this study were divided into 2 groups: 27 recipients with excellent long-term graft function and 13 recipients with acute rejection. After collection of whole peripheral blood, peripheral blood mononuclear cells were isolated from the blood samples. After RNAextraction and cDNAsynthesis from each collected sample, expression levels of interleukin 35 and FOXP3 were determined using in-house SYBER green-based real-time polymerase chain reaction. We used t tests to analyze data.

RESULTS

Mean ages of recipients with excellent longterm graft function and recipients with acute rejection were 42.1 and 45.5 years, respectively. We found that FOXP3 and interleukin 35 expression levels were significantly increased in recipients with excellentlongterm graftfunction comparedwith recipientswith acute rejection. FOXP3 expression levels were significantly higher in those with excellent long-term graft function with graft survivalrate of <10 years,whereas interleukin 35 expression levels were significantly higher in patients with graft survival rate >10 years (P < .05). Expression levels of FOXP3 and interleukin 35 were greater in those from 35 to 50 years old versus with those in the other age ranges.

CONCLUSIONS

Expression patterns of FOXP3 and interleukin 35 may have the potential to be used as prognostic biomarkers for kidney transplant outcomes.

Interleukin-35: Structure, Function and Its Impact on Immune-Related Diseases

The balance between inflammatory and anti-inflammatory immune responses is maintained through immunoregulatory cell populations and immunosuppressive cytokines. Interleukin-35 (IL-35), an inhibitory cytokine that belongs to the IL-12 family, is capable of potently suppressing T cell proliferation and inducing IL-35-producing induced regulatory T cells (iTr35) to limit inflammatory responses. Over the past decade, a growing number of studies have indicated that IL-35 plays an important role in controlling immune-related disorders, including autoimmune diseases, infectious diseases, and cancer. In this review, we summarize the current knowledge about the biology of IL-35 and its contribution in different diseases, and we discuss the potential of and barriers to harnessing IL-35 as a clinical biomarker or immunotherapy.

Urine and serum interleukin 35 as potential biomarkers of lupus nephritis

Introduction

Lupus nephritis (LN) is considered a serious manifestation of systemic lupus erythematosus (SLE). Therefore, a reliable non-invasive biomarker is a priority for monitoring renal involvement instead of the kidney biopsy. Interleukin 35 (IL-35) has an immunosuppressive and anti-inflammatory role in many autoimmune diseases. However, its role in LN still needs to be elucidated.

Aim of the study

To evaluate urine and serum levels of IL-35 in SLE patients with LN and without nephritis identifying their potential as biomarkers of renal involvement.

Material and methods

Urine and serum levels of IL-35 were measured in 42 SLE patients, divided into 22 with LN and 20 without LN, and 20 matched healthy controls using enzyme-linked immunosorbent assay (ELISA). SLE disease activity was assessed for patients by the Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K).

Results

Levels of serum and urine IL-35 were significantly higher (p < 0.001) in the LN group compared with those without LN and with controls. In LN patients, a strong correlation (p < 0.001) was observed between serum and urine IL-35 levels with SLEDAI-2K score (r = 0.677 and 0.806 respectively). Furthermore, proteinuria had a strong and significant correlation (p ˂ 0.001) with serum and urinary IL-35 levels in the patients with LN. Serum IL-35 had 90.9% sensitivity and 85% specificity while urine IL-35 had 95.5% sensitivity and 75% specificity to differentiate LN from healthy individuals.

Conclusions

Urine and serum IL-35 may aid in assessment of renal involvement in SLE patients, serving as potential biomarkers of LN.

The Mechanism of Interleukin-35 in Chronic Hepatitis B

Interleukin-35 (IL-35) is a newly identified inhibitory cytokine. It has recently been found to play an extremely important role in chronic hepatitis B disease, which makes it likely to be a target for new therapies for hepatitis B malady. IL-35 modulates a variety of immune mechanisms to cause persistent viral infections, such as affecting the ratio of helper T cells, reducing the activity of cytotoxic T cells, hindering the antigen presentation capacity for dendritic cells, and increasing the transcription level of hepatitis B virus. On the other hand, IL-35 can control the inflammation caused by hepatitis B liver injury. Therefore, to seek a breakthrough in curing hepatitis B disease, the contradictory part of IL-35 in the occurrence and development of this sickness is worthy of further discussion and research. This article will systematically review the biological effects of IL-35 and the specific mechanisms affecting the disease.

Investigation of the transcriptomic response in Atlantic salmon (Salmo salar) gill exposed to Paramoeba perurans during early onset of disease

Amoebic Gill Disease (AGD), caused by the protozoan extracellular parasite Paramoeba perurans (P. perurans) is a disease affecting Atlantic salmon (Salmo salar). This study investigated the gill transcriptomic profile of pre-clinical AGD using RNA-sequencing (RNA-seq) technology. RNA-seq libraries generated at 0, 4, 7, 14 and 16 days post infection (dpi) identified 19,251 differentially expressed genes (DEGs) of which 56.2% were up-regulated. DEGs mapped to 224 Gene Ontology (GO) terms including 140 biological processes (BP), 45 cellular components (CC), and 39 molecular functions (MF). A total of 27 reference pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) and 15 Reactome gene sets were identified. The RNA-seq data was validated using real-time, quantitative PCR (qPCR). A host immune response though the activation of complement and the acute phase genes was evident at 7 dpi, with a concurrent immune suppression involving cytokine signalling, notably in interleukins, interferon regulatory factors and tumour necrosis factor-alpha (tnf-α) genes. Down-regulated gene expression with involvement in receptor signalling pathways (NOD-like, Toll-like and RIG-1) were also identified. The results of this study support the theory that P. perurans can evade immune surveillance during the initial stages of gill colonisation through interference of signal transduction pathways.