Targeting IL-17 in autoimmunity and inflammation

The Functions of Cytokines in the Cardiac Immunopathogenesis of Chagas Disease

Chagas disease is a complex zoonosis. Clinically, it presents in two distinct phases, acute and chronic. The ability of patients to respond to Trypanosoma cruzi infection depends on the balance between inflammatory and anti-inflammatory responses, in which cytokines play a key regulatory role. In this review, we discuss the role of cytokines in regulating the host response and as mediators of cardiac injury by inducing profibrotic alterations. The importance of characterizing cytokine profiles as biomarkers of the evolution of cardiac damage in T.-cruzi-infected individuals is also emphasized.

IL-17 in wound repair: bridging acute and chronic responses

Chronic wounds, resulting from persistent inflammation, can trigger a cascade of detrimental effects including exacerbating inflammatory cytokines, compromised blood circulation at the wound site, elevation of white blood cell count, increased reactive oxygen species, and the potential risk of bacterial infection. The interleukin-17 (IL-17) signaling pathway, which plays a crucial role in regulating immune responses, has been identified as a promising target for treating inflammatory skin diseases. This review aims to delve deeper into the potential pathological role and molecular mechanisms of the IL-17 family and its pathways in wound repair. The intricate interactions between IL-17 and other cytokines will be discussed in detail, along with the activation of various signaling pathways, to provide a comprehensive understanding of IL-17's involvement in chronic wound inflammation and repair.

Effect of sublingual immunotherapy on clinical and laboratory autoimmunity

Background: There still are few data on the long-term safety of sublingual immunotherapy (SLIT). The aim of this study was to assess the appearance of autoimmune diseases in patients before and after SLIT. Materials & methods: New cases of autoimmune diseases were monitored. Patients in the SLIT group (n = 816) were compared with controls (n = 1096). Results: The new incidences of autoimmune diseases in the SLIT group were lower compared with the control group: 18 (2.2%) versus 58 (5.3%); p < 0.05. Systemic lupus erythematosus, psoriasis and Hashimoto appeared much more often in the control group. Conclusion: SLIT had no significant effect on the induction of autoimmune diseases.

The IL-17 family in diseases: from bench to bedside

The interleukin-17 (IL-17) family comprises six members (IL-17A-17F), and recently, all of its related receptors have been discovered. IL-17 was first discovered approximately 30 years ago. Members of this family have various biological functions, including driving an inflammatory cascade during infections and autoimmune diseases, as well as boosting protective immunity against various pathogens. IL-17 is a highly versatile proinflammatory cytokine necessary for vital processes including host immune defenses, tissue repair, inflammatory disease pathogenesis, and cancer progression. However, how IL-17 performs these functions remains controversial. The multifunctional properties of IL-17 have attracted research interest, and emerging data have gradually improved our understanding of the IL-17 signaling pathway. However, a comprehensive review is required to understand its role in both host defense functions and pathogenesis in the body. This review can aid researchers in better understanding the mechanisms underlying IL-17's roles in vivo and provide a theoretical basis for future studies aiming to regulate IL-17 expression and function. This review discusses recent progress in understanding the IL-17 signaling pathway and its physiological roles. In addition, we present the mechanism underlying IL-17's role in various pathologies, particularly, in IL-17-induced systemic lupus erythematosus and IL-17-related tumor cell transformation and metastasis. In addition, we have briefly discussed promising developments in the diagnosis and treatment of autoimmune diseases and tumors.

Regulatory mechanism underlying liver X receptor effects on the tumor microenvironment, inflammation and tumorigenesis

INTRODUCTION

Liver X receptors (LXRs) have emerged as novel targets for tumor treatment. LXRs within the tumor microenvironment show the capacity to impact tumorigenesis and tumor development by regulating the infiltration of immune cells and release of cytokines to moderate inflammation.

AREAS COVERED

In this review, we present a systematic description of recent progress in understanding the impact of LXRs on the tumor microenvironment and tumorigenesis. We also summarize the antitumor effects mediated by LXRs via their regulation of cytokine expression. Additionally, we discuss the limitations of LXR research in tumor studies to date.

EXPERT OPINION

Previous studies have demonstrated abnormal LXR expression in tumor tissues, and activation of LXRs has been shown to inhibit tumorigenesis and promote apoptosis in tumor cells. However, LXRs can also affect tumorigenesis by regulating immune cell functions within the tumor immune microenvironment. By summarizing the impact of LXRs on immune cells, we provide new insights into the multifaceted nature of LXRs as antitumor targets.

Triterpenoid saponins from Camellia sinensis roots with cytotoxic and immunomodulatory effects

Camellia sinensis L. (Theaceae) leaves have been used as a beverage in both Eastern and Western cultures for a long time, while its root has not been intensively studied. In this study, seven undescribed triterpenoid saponins (1-7) and twelve known saponins (8-19) with different combinations of substituents, such as oxygenated isoprenyl substituents and sugar moieties, and lengths of sugar chains, were isolated from the C. sinensis roots. Their structures were unequivocally determined using one- and two-dimensional nuclear magnetic resonance data and acid hydrolysis analysis. Investigation of the biological activities of isolated compounds revealed that only those without functional acetyl groups exhibited cytotoxic activities against mouse and human cancer cells (B16F10) and human cervical cancer cell line (HeLa) at 50 μM. Compounds with an aldehyde group at C-23 of aglycone showed immunomodulatory activity against Th1 and Th17 cells at 10 μM. Ten compounds with biological activities from C. sinensis roots extracts, including three previously undescribed ones (3, 6, and 7), were identified.

Pharmacological inhibitors of β-cell dysfunction and death as therapeutics for diabetes

More than 500 million adults suffer from diabetes worldwide, and this number is constantly increasing. Diabetes causes 5 million deaths per year and huge healthcare costs per year. β-cell death is the major cause of type 1 diabetes. β-cell secretory dysfunction plays a key role in the development of type 2 diabetes. A loss of β-cell mass due to apoptotic death has also been proposed as critical for the pathogenesis of type 2 diabetes. Death of β-cells is caused by multiple factors including pro-inflammatory cytokines, chronic hyperglycemia (glucotoxicity), certain fatty acids at high concentrations (lipotoxicity), reactive oxygen species, endoplasmic reticulum stress, and islet amyloid deposits. Unfortunately, none of the currently available antidiabetic drugs favor the maintenance of endogenous β-cell functional mass, indicating an unmet medical need. Here, we comprehensively review over the last ten years the investigation and identification of molecules of pharmacological interest for protecting β-cells against dysfunction and apoptotic death which could pave the way for the development of innovative therapies for diabetes.

Blood immunological profile of abdominal aortic aneurysm based on autoimmune injury

Abdominal aortic aneurysm (AAA) occupies a large part of aorta aneurysm, and if there's no timely intervention or treatment, the risks of rupture and death would rise sharply. With the depth of research in AAA, more and more evidence showed correlations between AAA and autoimmune injury. Currently, a variety of bioactive peptides and cells have been confirmed to be related with AAA progression. Despite the tremendous progress, more than half researches were sampling from lesion tissues, which would be difficult to obtain. Given that the intrusiveness and convenience, serological test take advantages in initial diagnosis. Here we review blood biomarkers associated with autoimmune injury work in AAA evolution, aiming to make a profile on blood immune substances of AAA and provide a thought for potential clinical practice.

Interleukin 17 and Its Involvement in Renal Cell Carcinoma

Nowadays, molecular and immunological research is essential for the better understanding of tumor cells pathophysiology. The increasing number of neoplasms has been taken under ‘the molecular magnifying glass’ and, therefore, it is possible to discover complex relationships between the cytophysiology and immune system action. An example could be renal cell carcinoma (RCC) which has deep interactions with immune mediators such as Interleukin 17 (IL-17)—an inflammatory cytokine reacting to tissue damage and external pathogens. RCC is one of the most fatal urological cancers because of its often late diagnosis and poor susceptibility to therapies. IL-17 and its relationship with tumors is extremely complex and constitutes a recent topic for numerous studies. What is worth highlighting is IL-17’s dual character in cancer development—it could be pro- as well as anti-tumorigenic. The aim of this review is to summarize the newest data considering multiple connections between IL-17 and RCC.

Microbes, Histology, Blood Analysis, Enterotoxins, and Cytokines: Findings From the ASERF Systemic Symptoms in Women-Biospecimen Analysis Study: Part 3

BACKGROUND

There has been an increasing need to acquire rigorous scientific data to answer the concerns of physicians, patients, and the FDA regarding the self-reported illness identified as breast implant illness (BII). There are no diagnostic tests or specific laboratory values to explain the reported systemic symptoms described by these patients.

OBJECTIVES

The aim of this study was to determine if there are quantifiable laboratory findings that can be identified in blood, capsule tissue pathology, or microbes that differentiate women with systemic symptoms they attribute to their implants from 2 control groups.

METHODS

A prospective blinded study enrolled 150 subjects into 3 cohorts: (A) women with systemic symptoms they attribute to implants who requested implant removal; (B) women with breast implants requesting removal or exchange who did not have symptoms attributed to implants; and (C) women undergoing cosmetic mastopexy who have never had any implanted medical device. Capsule tissue underwent detailed analysis and blood was sent from all 3 cohorts to evaluate for markers of inflammation.

RESULTS

No significant histologic differences were identified between the cohorts, except there were more capsules with synovial metaplasia in the non-BII cohort. There was no statistical difference in thyroid-stimulating hormone, vitamin D levels, or complete blood count with differential between the cohorts. Next-generation sequencing revealed no statistically significant difference in positivity between Cohort A and B. Of the 12 cytokines measured, 3 cytokines, interleukin (IL)-17A, IL-13, and IL-22, were found to be significantly more often elevated in sera of subjects in Cohort A than in Cohorts B or C. The enterotoxin data demonstrated an elevation in immunoglobulin G (IgG) anti-Staphylococcus aureus enterotoxin A in Cohort A. There was no correlation between the presence of IgE or IgG anti-Staphylococcal antibody and a positive next-generation sequencing result.

CONCLUSIONS

This study adds to the current literature by demonstrating few identifiable biomedical markers to explain the systemic symptoms self-reported by patients with BII.

Essential role of IL-17 in acute exacerbation of pulmonary fibrosis induced by non-typeable Haemophilus influenzae

Background: Acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) has a poor prognosis and lacks effective therapy. Animal models that mimic AE-IPF can greatly accelerate investigation of its pathogenesis and development of effective therapy. However, there are few reports of animal models of AE-IPF caused by bacteria. Thus, our study aimed to establish a mouse model of bacterium-induced AE-IPF and explore the potential pathogenic mechanism of AE-IPF. Methods: Mice were instilled intranasally with bleomycin (BLM) followed by non-typeable Haemophilus influenzae (NTHi) strain NT127. Murine survival, bacterial load, body weight and pulmonary histopathological changes were evaluated. We analyzed the T cell and inflammatory cell responses in the lungs. Results: Infection with 10⁷ CFU NT127 triggered AE in mice with PF induced by 30 μg BLM. Compared with BLM-instilled mice, the BLM/NT127-treated mice showed more obvious airway inflammation, lower survival rate, higher inflammatory cell response, and increased proportions and numbers of IL-17⁺CD4⁺, IL-17⁺ γδ T, IL-22⁺CD4⁺ and regulatory T (Treg) cells in lungs. γδ T cells were the predominant source of IL-17. IL-17 gene knockout mice with AE-IPF had quicker body weight recovery, milder pulmonary inflammation and fibrosis, stronger IL-22⁺CD4⁺T, TGF-β⁺ γδ T and Treg cell responses, and weaker neutrophil and eosinophil responses than wild-type mice with AE-IPF. Conclusions: NTHi infection after BLM-induced IPF can cause AE-IPF in a murine model. This novel model can be used to investigate the pathogenesis of AE-IPF and develop new therapies for AE-IPF caused by bacteria. IL-17 is essential for the development of AE-IPF, and it may be a new therapeutic target for bacteria-induced AE-IPF.

Morphine in Combination with Ketamine Improves Cervical Cancer Pain and Suppresses Immune Function via the JAK3/STAT5 Pathway

Background

The role of ketamine as an adjuvant for morphine in the treatment of cancer pain and immune functions has been confirmed. This study aimed to explore the role of morphine and ketamine on cancer pain and T cells of patients with cervical cancer (CC).

Methods

T cells were isolated from peripheral blood mononuclear cells (PBMC) of CC patients by positive selection using anti-CD3 beads. The isolated T cells were assigned into three groups: the control group, the morphine group, and the morphine + ketamine (Mor + Ket) group. The percentages of CD4⁺ and CD8⁺ were analyzed by flow cytometry. The levels of interferon (IFN)-γ, interleukin (IL)-2, and IL-17 and the corresponding mRNA expression in vitro were determined using ELISA and qRT-PCR, respectively. Western blotting was used for detection of JAK3/STAT5 pathway-related proteins after naltrexone treatment in vitro. Afterwards, all the patients were further divided into the morphine group and the Mor + Ket group in accordance with the principles of the randomized and double-blind method to assess pain intensity.

Results

Our in vivo results showed that drug combinations relieved cancer pain more effectively than morphine intervention. The in vitro results demonstrated that the combination of morphine and ketamine may decrease CD4⁺ percentage, CD4⁺/CD8⁺ ratio, and the levels of IFN-γ, IL-2, and IL-17 via the JAK3/STAT5 pathway.

Conclusions

Our finding indicated that morphine-ketamine combination could improve cancer pain and repress immune function via the JAK3/STAT5 pathway in the progression of CC.

Identification of Inflammatory and Regulatory Cytokines IL-1α-, IL-4-, IL-6-, IL-12-, IL-13-, IL-17A-, TNF-α-, and IFN-γ-Producing Cells in the Milk of Dairy Cows with Subclinical and Clinical Mastitis

In naturally occurring bovine mastitis, effects of infection depend on the host inflammatory response, including the effects of secreted cytokines. Knowledge about the inflammatory and regulatory cytokines in milk cells of free-stall barn dairy cows and in naturally occurring mastitis is lacking as most studies focus on induced mastitis. Hereby, the aim of the study was to determine inflammatory and regulatory cytokines in the milk of dairy cows with subclinical and clinical mastitis. The following examinations of milk samples were performed: differential counting of somatic cells (SCC), bacteriological examination, and immunocytochemical analysis. Mean SCC increased in subclinical and clinical mastitis cases. The number of pathogenic mastitis-causing bacteria on plates increased in subclinical mastitis cases but decreased in clinical mastitis. The inflammatory and regulatory markers in the milk cells of healthy cows showed the highest mean cell numbers (%). In mastitis cases, immunoreactivity was more pronounced for IL-4, IL-6, IL-12, IL-13, IL-17A, TNF-α, and IFN-γ. Data about subclinical and clinical mastitis demonstrate inflammatory responses to intramammary infection driven by IL-1α, IL-4, and IL-17A. Moreover, the host defense response in mastitis is characterized by continuation or resolution of initial inflammation. IL-12 and INF-γ immunoreactivity was recognized to differ mastitis cases from the relative health status.

[Association of self-rated health with inflammatory markers among nursing home employees]

OBJECTIVES

Although self-rated health (SRH), the self-evaluation of one's own health status, has been reported to be associated with the immune status, the relationship between three different SRH measures (global, self-comparative, and age-comparative) with inflammatory markers as well as the relative strength of these associations by age are not well understood. The current study investigated the associations between SRH measures and inflammatory markers among nursing home employees.

METHODS

A sample of 120 Japanese employees at a nursing home (90 women and 30 men), aged 21-68 years (mean, 40.9 years), underwent a blood test for the measurement of inflammatory markers (interferon-γ, interleukin [IL]-4, IL-6, and tumor necrosis factor [TNF]-α, white blood cell count) and SRH during the annual health checkup. Multiple regression analysis adjusted for covariates was performed to analyze the relationship between inflammatory markers and SRH measures stratified by age, that is, aged < 40 years (younger age group) and 40 years and over (older age group).

RESULTS

Among the participants aged 40 years and over, poor global SRH was significantly associated with an increase in IL-6, while poor age-comparative SRH was significantly associated with an increase in TNF-α among participants aged < 40 years in the fully adjusted model controlling for potential confounders. Age-comparative SRH was also significantly associated with an increase in IL-6 among all participants. Self-comparative SRH was not significantly associated with inflammatory markers.

CONCLUSIONS

Our results suggest that three SRH measures are not equivalently associated with inflammatory markers, especially when the analyses were performed separately for the younger and older populations. This implies that not only differences in forms of SRH but also in age modify the relationship between SRH and inflammatory markers.

Type 17 immunity promotes the exhaustion of CD8+ T cells in cancer

Background

Multiple types of immune cells producing IL-17 are found in the tumor microenvironment. However, their roles in tumor progression and exhaustion of CD8⁺ tumor-infiltrating lymphocytes (TILs) remain unclear.

Methods

To determine the role of type 17 immunity in tumor, we investigated the growth of B16F10 melanoma and the exhaustion of CD8⁺ TILs in Il17a^−/− mice, Il17a^CreR26^DTA mice, RORγt inhibitor-treated mice, or their respective control mice. Adoptive transfer of tumor-specific IL-17-producing T cells was performed in B16F10-bearing congenic mice. Anti-CD4 or anti-Ly6G antibodies were used to deplete CD4⁺ T cells or CD11b⁺Gr-1^hi myeloid cells in vivo, respectively. Correlation between type 17 immunity and T cell exhaustion in human cancer was evaluated by interrogating TCGA dataset.

Results

Depletion of CD4⁺ T cells promotes the exhaustion of CD8⁺ T cells with a concomitant increase in IL-17-producing CD8⁺ T (Tc17) cells in the tumor. Unlike IFN-γ-producing CD8⁺ T (Tc1) cells, tumor-infiltrating Tc17 cells exhibit CD103⁺KLRG1⁻IL-7Rα^hi tissue resident memory-like phenotypes and are poorly cytolytic. Adoptive transfer of IL-17-producing tumor-specific T cells increases, while depletion of IL-17-producing cells decreases, the frequency of PD-1^hiTim3⁺TOX⁺ terminally exhausted CD8⁺ T cells in the tumor. Blockade of IL-17 or RORγt pathway inhibits exhaustion of CD8⁺ T cells and also delays tumor growth in vivo. Consistent with these results, human TCGA analyses reveal a strong positive correlation between type 17 and CD8⁺ T cell exhaustion signature gene sets in multiple cancers.

Conclusion

IL-17-producing cells promote terminal exhaustion of CD8⁺ T cells and tumor progression in vivo, which can be reversed by blockade of IL-17 or RORγt pathway. These findings unveil a novel role for IL-17-producing cells as tumor-promoting cells facilitating CD8⁺ T cell exhaustion, and propose type 17 immunity as a promising target for cancer immunotherapy.

Gardenia Jasminoides Ameliorates Antibiotic-Associated Aggravation of DNCB-Induced Atopic Dermatitis by Restoring the Intestinal Microbiome Profile

The intestinal microbiome is considered one of the key regulators of health. Accordingly, the severity of atopic dermatitis (AD) is mediated by the skin and intestinal microbiome environment. In this study, while evaluating the aggravation in AD symptoms by the antibiotics cocktail (ABX)-induced depletion of the intestinal microbiome, we sought to verify the effect of Gardenia jasminoides (GJ), a medicinal herb used for inflammatory diseases, on AD regarding its role on the intestinal microbiome. To verify the aggravation in AD symptoms induced by the depletion of the intestinal microbiome, we established a novel mouse model by administrating an ABX to create a microbiome-free environment in the intestine, and then applied 2,4-dinitrochlorobenzene (DNCB) to induce an AD-like skin inflammatory response. While ABX treatment aggravated AD-like symptoms, the 2-week administration of GJ improved these pathological changes. DNCB application upregulated immune cell count and serum cytokine expression, which were alleviated by GJ. Moreover, pathological alterations by antibiotics and DNCB, including histological damage of the intestine and the intestinal expression of IL-17, were recovered in GJ-treated mice. The beneficial effect of GJ was due to the restoration of the intestinal microbiome composition. Overall, we suggest GJ as a potential therapeutic agent for AD due to its regulation of the intestinal microbiome.

Polar functional group-containing glycolipid CD1d ligands modulate cytokine-biasing responses and prevent experimental colitis

The MHC class I-like molecule CD1d is a nonpolymorphic antigen-presenting glycoprotein, and its ligands include glycolipids, such as α-GalCer. The complexes between CD1d and ligands activate natural killer T cells by T cell receptor recognition, leading to the secretion of various cytokines (IFN-γ, IL-4, IL-17A, etc.). Herein, we report structure-activity relationship studies of α-GalCer derivatives containing various functional groups in their lipid acyl chains. Several derivatives have been identified as potent CD1d ligands displaying higher cytokine induction levels and/or unique cytokine polarization. The studies also indicated that flexibility of the lipid moiety can affect the binding affinity, the total cytokine production level and/or cytokine biasing. Based on our immunological evaluation and investigation of physicochemical properties, we chose bisamide- and Bz amide-containing derivatives 2 and 3, and evaluated their in vivo efficacy in a DSS-induced model of ulcerative colitis. The derivative 3 that exhibits Th2- and Th17-biasing responses, demonstrated significant protective effects against intestinal inflammation in the DSS-induced model, after a single intraperitoneal injection.

Role of Phosphodiesterase 7 (PDE7) in T Cell Activity. Effects of Selective PDE7 Inhibitors and Dual PDE4/7 Inhibitors on T Cell Functions

Phosphodiesterase 7 (PDE7), a cAMP-specific PDE family, insensitive to rolipram, is present in many immune cells, including T lymphocytes. Two genes of PDE7 have been identified: PDE7A and PDE7B with three or four splice variants, respectively. Both PDE7A and PDE7B are expressed in T cells, and the predominant splice variant in these cells is PDE7A1. PDE7 is one of several PDE families that terminates biological functions of cAMP—a major regulating intracellular factor. However, the precise role of PDE7 in T cell activation and function is still ambiguous. Some authors reported its crucial role in T cell activation, while according to other studies PDE7 activity was not pivotal to T cells. Several studies showed that inhibition of PDE7 by its selective or dual PDE4/7 inhibitors suppresses T cell activity, and consequently T-mediated immune response. Taken together, it seems quite likely that simultaneous inhibition of PDE4 and PDE7 by dual PDE4/7 inhibitors or a combination of selective PDE4 and PDE7 remains the most interesting therapeutic target for the treatment of some immune-related disorders, such as autoimmune diseases, or selected respiratory diseases. An interesting direction of future studies could also be using a combination of selective PDE7 and PDE3 inhibitors.

Comparison of inflammatory cytokines levels in the aqueous humor with diabetic retinopathy

PURPOSE

Evidence has accumulated suggesting that various inflammatory cytokines are involved in the progress of diabetic retinopathy (DR), but there are few studies concerning the relationship between individual cytokines levels in the aqueous humor (AH) and the severity of DR. This study aimed to explore the differences of interleukin (IL)-23, IL-17, IL-10 and transforming growth factor (TGF)-β in AH form patients with different proliferative stages of DR.

METHODS

From June 2016 to June 2019, patients for senile cataract surgery were enrolled with the informed consent. All cases were graded into 4 groups: the control group (patients without diabetes), non-retinopathy (NDR) group (diabetic patients without retinopathy), non-proliferative diabetic retinopathy (NPDR) group, and proliferative diabetic retinopathy (PDR) group. The concentrations of IL-23, IL-17, IL-10, and TGF-β in AH were measured using ELISA and compared them within four groups by ANOVA.

RESULTS

In this study, 20 (28.57%), 18 (25.71%), 17 (24.29%), and 15 (21.43%) patients were included in the control, NDR, NPDR, and PDR groups, respectively. There had no significant differences in demographic characteristics (P > 0.05). Comparison of these cytokines within four groups revealed: the IL-23 level was increased in NDR group initially and raised along with the progression of DR (P < 0.01). The IL-17 level was significantly higher in NPDR and PDR groups compared to NDR and the control groups, and positively correlated with more-severe DR (P < 0.01). By contrast, The IL-10 level was significantly lower in diabetic patients than in non-diabetic controls, and decreased as the severity of DR increased (P < 0.05). In addition, TGF-β was also elevated in diabetic patients, but showed no differences based on the presence or severity of DR (P > 0.05).

CONCLUSIONS

The over-expression of IL-23 and IL-17 in AH might have a synergistic effect on the pathogenesis well before the proliferative stage, and was typical positively correlated with the severity of DR. These results offer a novel early therapeutic target for DR.

Anti-Aminoacyl Transfer-RNA-Synthetases (Anti-tRNA) Autoantibodies Associated with Interstitial Lung Disease: Pulmonary Disease Progression has a Persistent Elevation of the Th17 Cytokine Profile

Anti-tRNA autoantibodies are associated with interstitial lung disease (ILD), in at least two clinical scenarios: the anti-synthetase syndrome (ASSD) and interstitial pneumonia with autoimmune features (IPAF). Under pathological conditions, cytokines indicate the participating elements and the course of inflammatory phenomena. We aimed to quantify serum concentrations of different inflammatory cytokines profiles in patients with anti-tRNA associated ILD (anti-tRNA-ILD) and estimate the association between these and ILD improvement and progression. Serum levels of 18 cytokines from baseline and after six months of treatment of ILD patients’ positives to anti-tRNA were included in the current study. At six months, patients were classified as with or without ILD progression. A total of 39 patients were included (10 anti-Jo1, eight anti-PL7, 11 anti-PL12, and 10 anti-Ej). Three patients (7.6%) had ILD progression (progressors patients, PP) and showed statistically higher levels in IL-4, IL-10, IL-17A, IL-22, GM-CSF, IL-1β, IL-6, IL-12, IL-18, and TNF-α, compared to patients without disease progression (no progressors patients, NPP). IL-17A, IL-1β, and IL-6 (T-helper-lymphocyte (Th)17 inflammatory cytokine profile) were elevated and had a high discriminatory capacity in distinguishing ILD PP of those NPP at follow-up. Overall, there is an association between the cytokines of the Th17 inflammatory profile and the ASSD progression.

[Role of tumor necrosis factor-α in Chlamydia Muridarum infection in the urogenital tract of mice]

OBJECTIVE

To explore the role of tumor necrosis factor-α (TNF-α) in immune response to urogenital chlamydial infection and urogenital pathology in mice.

METHODS

Fifteen female wild-type (WT) C57BL/6J mice and 15 TNF-α receptor knockout (TNF-αR KO) mice were inoculated intravaginally with 1×104 inclusion forming units (IFUs) of live C. muridarum. At 56 days after the first inoculation, 8 mice from each group were subjected to a second inoculation at the same dose. Vaginal swabs were taken every 3 or 4 days to detect the number of inclusion bodies of chlamydia. On day 80 after the first inoculation, the mice were euthanized and peritoneal macrophages were collected and the vaginal tract and spleen were dissected. The pathologies in the fallopian tube and the uterine horn were observed and the severity of inflammatory cell infiltration and lumen dilatation were semi-quantitatively scored. The levels of interleukin-6 (IL-6), IL-8, IL-1α, IL-1β and TNF-α in the supernatant of the peritoneal macrophage were detected. Spleen cell suspension was prepared, and after stimulation with chlamydia EB in vitro, the levels of the cytokines including IL-4, IL-5, IL-17 and interferon-γ (IFN-γ) were determined in the cells.

RESULTS

The clearance rate of Chlamydia from the urogenital tract was similar between TNF-αR KO mice and WT mice regardless of the primary or second infection. The severity of inflammation in the fallopian tube and the uterine horn did not differ significantly between the two groups, but TNF-αR KO mice had significantly milder dilation of the fallopian tubes (P < 0.05). The peritoneal macrophages from TNF-αR KO mice produced a significantly higher level of TNF-α than those from WT mice (P < 0.05); the spleen cells from the two groups both produced high levels of IFN-γ, but IL-17 production by the spleen cells was significantly lower in TNF-αR KO mice than in WT mice (P < 0.05).

CONCLUSIONS

TNF-α is not associated with protective immune response against C. muridarum infection, and can worsen the inflammatory damages of the urogenital tract caused by C. muridarum in mice.

Remission of autoimmune diabetes by anti-TCR combination therapies with anti-IL-17A or/and anti-IL-6 in the IDDM rat model of type 1 diabetes

BACKGROUND

The cytokine IL-17 is a key player in autoimmune processes, while the cytokine IL-6 is responsible for the chronification of inflammation. However, their roles in type 1 diabetes development are still unknown.

METHODS

Therefore, therapies for 5 days with anti-IL-17A or anti-IL-6 in combination with a T cell-specific antibody, anti-TCR, or in a triple combination were initiated immediately after disease manifestation to reverse the diabetic metabolic state in the LEW.1AR1-iddm (IDDM) rat, a model of human type 1 diabetes.

RESULTS

Monotherapies with anti-IL-6 or anti-IL-17 showed no sustained anti-diabetic effects. Only the combination therapy of anti-TCR with anti-IL-6 or anti-IL-17 at starting blood glucose concentrations up to 12 mmol/l restored normoglycaemia. The triple antibody combination therapy was effective even up to very high initial blood glucose concentrations (17 mmol/l). The β cell mass was raised to values of around 6 mg corresponding to those of normoglycaemic controls. In parallel, the apoptosis rate of β cells was reduced and the proliferation rate increased as well as the islet immune cell infiltrate was strongly reduced in double and abolished in triple combination therapies.

CONCLUSIONS

The anti-TCR combination therapy with anti-IL-17 preferentially raised the β cell mass as a result of β cell proliferation while anti-IL-6 strongly reduced β cell apoptosis and the islet immune cell infiltrate with a modest increase of the β cell mass only. The triple combination therapy achieved both goals in a complimentary anti-autoimmune and anti-inflammatory action resulting in sustained normoglycaemia with normalized serum C-peptide concentrations.

IL-17-Producing Cells in Tumor Immunity: Friends or Foes?

IL-17 is produced by RAR-related orphan receptor gamma t (RORγt)-expressing cells including Th17 cells, subsets of γδT cells and innate lymphoid cells (ILCs). The biological significance of IL-17-producing cells is well-studied in contexts of inflammation, autoimmunity and host defense against infection. While most of available studies in tumor immunity mainly focused on the role of T-bet-expressing cells, including cytotoxic CD8⁺ T cells and NK cells, and their exhaustion status, the role of IL-17-producing cells remains poorly understood. While IL-17-producing T-cells were shown to be anti-tumorigenic in adoptive T-cell therapy settings, mice deficient in type 17 genes suggest a protumorigenic potential of IL-17-producing cells. This review discusses the features of IL-17-producing cells, of both lymphocytic and myeloid origins, as well as their suggested pro- and/or anti-tumorigenic functions in an organ-dependent context. Potential therapeutic approaches targeting these cells in the tumor microenvironment will also be discussed.

High activation and skewed T cell differentiation are associated with low IL-17A levels in a hu-PBL-NSG-SGM3 mouse model of HIV infection

The humanized NOD/SCID/IL-2 receptor γ-chain^null (NSG) mouse model has been widely used for the study of HIV pathogenesis. Here, NSG mice with transgenic expression of human stem cell factor (SCF), granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-3 (NSG-SGM3) were injected with peripheral blood leukocytes (PBL mice) from two HIV-infected (HIV⁺ ) patients who were under anti-retroviral therapy (ART; referred as HIV⁺ mice) or one HIV-seronegative healthy volunteer (HIV^- ). Such mice are either hu-PBL-NSG-SGM3 HIV⁺ or HIV^- mice, depending on the source of PBL. The kinetics of HIV replication and T cell responses following engraftment were evaluated in peripheral blood and secondary lymphoid tissues. High HIV replication and low CD4 : CD8 ratios were observed in HIV⁺ mice in the absence of anti-retroviral therapy (ART). Consistent with high activation and skewed differentiation of T cells from the HIV-infected donor, HIV⁺ mice exhibited a higher T cell co-expression of human leukocyte antigen D-related (HLA-DR) and CD38 than HIV^- mice, as well as a shifted differentiation to a CCR7^- CD45RA⁺ terminal effector profile, even in the presence of ART. In addition, HIV replication and the activation/differentiation disturbances of T cells were associated with decreased plasma levels of IL-17A. Thus, this hu-PBL-NSG-SGM3 mouse model recapitulates some immune disturbances occurring in HIV-infected patients, underlying its potential use for studying pathogenic events during this infection.

A Critical Regulation of Th17 Cell Responses and Autoimmune Neuro-Inflammation by Ginsenoside Rg3

Among diverse helper T-cell subsets, Th17 cells appear to be pathogenic in diverse autoimmune diseases, and thus, targeting Th17 cells could be beneficial for the treatment of the diseases in humans. Ginsenoside Rg3 is one of the most potent components in Korean Red Ginseng (KRG; Panax ginseng Meyer) in ameliorating inflammatory responses. However, the role of Rg3 in Th17 cells and Th17-mediated autoimmunity is unclear. We found that Rg3 significantly inhibited the differentiation of Th17 cells from naïve precursors in a dendritic cell (DC)–T co-culture system. While Rg3 minimally affected the secretion of IL-6, TNFα, and IL-12p40 from DCs, it significantly hampered the expression of IL-17A and RORγt in T cells in a T-cell-intrinsic manner. Moreover, Rg3 alleviated the onset and severity of experimental autoimmune encephalomyelitis (EAE), induced by transferring myelin oligodendrocyte glycoprotein (MOG)-reactive T cells. Our findings demonstrate that Rg3 inhibited Th17 differentiation and Th17-mediated neuro-inflammation, suggesting Rg3 as a potential candidate for resolving Th17-related autoimmune diseases.

Riemerella anatipestifer infection in ducks induces IL-17A production, but not IL-23p19

R. anatipestifer (RA) is one of the most harmful bacterial pathogens affecting the duck industry, and infection is associated with the production of proinflammatory cytokines, including IL-17A. Another proinflammatory cytokine, IL-23, is critical for the development of Th17 cells, which produce IL-17. However, IL-23 roles have not been studied in this infection. Here, we describe the identification and mRNA expression analysis of duck IL-23p19 (duIL-23p19) in splenic lymphocytes and macrophages stimulated with killed RA and in spleens of RA-infected ducks. Expression of duIL-23p19 transcript identified in this study was relatively high in livers of healthy ducks and was upregulated in mitogen-activated splenic lymphocytes as well as in splenic lymphocytes and macrophages stimulated with killed RA. In spleens of RA-infected ducks, expression levels of duIL-23p19 transcript were unchanged at all time points except on days 4 and 7 post-infection; however, duIL-17A and IL-17F expression levels were upregulated in both spleens of RA-infected ducks and splenic lymphocytes and macrophages stimulated with killed RA. In sera collected at 24 h after this infection, duIL-23p19 expression levels were unchanged, whereas IL-17A significantly upregulated. These results suggest that IL-23p19 does not play a critical role in the IL-17A response in early stages of RA-infected ducks.

The expression and clinical significance of serum IL-17 in patients with primary biliary cirrhosis

Background

We aimed to investigate the expression and clinical significance of interleukin 17 (IL-17) in patients with primary biliary cirrhosis (PBC).

Methods

PBC patients (n=127), patients without PBC (n=100) were selected from January 2015 to December 2015.The measure of IL-17 level was performed by cytometric beads array (CBA), immunohistochemistry and real-time PCR (QRT-PCR).

Results

The expression levels of serum IL-17, IL-6, IFN-γ, TNF-α and IL-10 in PBC groups were significantly higher than control group, a positively correlation between IL-17 and ALT, ALP, GGT, CIV was observed in PBC patients (r=0.350, P=0.013; r=0.373, P=0.008; r=0.337, P=0.017; r=0.349, P=0.021). In addition, IL-17 mRNA expression level in PBC group was higher than control group. Immunohistochemical results suggest that positive cells did not appear in normal tissues, while they appeared in the PBC liver tissue, mainly in the bile duct.

Conclusions

This study shows that IL-17 over expressed in PBC patients, it played a pro-inflammatory effect in the pathogenesis of PBC, most probably as a targeting drug research.

Vasoactive intestinal peptide inhibits the activation of murine fibroblasts and expression of interleukin 17 receptor C

Acute respiratory distress syndrome (ARDS) is an acute, severe, and refractory pulmonary inflammation with high morbidity and mortality. Excessive activation of fibroblast during the fibroproliferative phase plays a pivotal role in the prognosis of ARDS. Our previous study demonstrated that the vasoactive intestinal peptide (VIP) is mediated by lentivirus attenuates lipopolysaccharide (LPS)-induced ARDS in a murine model, and VIP inhibits the release of interleukin-17A (IL-17A) from activation macrophages. However, the effects of VIP on the activation of murine fibroblast and expression of IL-17 receptor (IL-17R) in ARDS remain unclear. Here, a mouse model of ARDS was established by an intratracheal injection of LPS. We found that the gene expression of col3a1 and hydroxyproline contents in the lungs were significantly increased 24 h after LPS injection. IL-17RC rather than IL-17RA was increased in the lungs of mice with ARDS. In vitro, LPS activated NIH3T3 cells, which was suppressed by VIP in a dose-dependent manner. In detail, VIP reduced the hydroxyproline content and col3a1 messenger RNA induced by LPS in NIH3T3 cells, as well as the expression of α-smooth muscle actin. Furthermore, we found that VIP inhibited the expression of IL-17R in the lungs of mice with ARDS and NIH3T3 cells stimulated with LPS, which was partly inhibited by antagonists of protein kinase A and protein kinase C. Taken together, our results demonstrated that VIP inhibited the activation of fibroblast via downregulation of IL-17RC, which may contribute to the protective effects of VIP against ARDS in mice.

Disruption of the Blood-Brain Barrier During Neuroinflammatory and Neuroinfectious Diseases

As the organ of highest metabolic demand, utilizing over 25% of total body glucose utilization via an enormous vasculature with one capillary every 73 μm, the brain evolves a barrier at the capillary and postcapillary venules to prevent toxicity during serum fluctuations in metabolites and hormones, to limit brain swelling during inflammation, and to prevent pathogen invasion. Understanding of neuroprotective barriers has since evolved to incorporate the neurovascular unit (NVU), the blood-cerebrospinal fluid (CSF) barrier, and the presence of CNS lymphatics that allow leukocyte egress. Identification of the cellular and molecular participants in BBB function at the NVU has allowed detailed analyses of mechanisms that contribute to BBB dysfunction in various disease states, which include both autoimmune and infectious etiologies. This chapter will introduce some of the cellular and molecular components that promote barrier function but may be manipulated by inflammatory mediators or pathogens during neuroinflammation or neuroinfectious diseases.

Mechanisms by Which the Gut Microbiota Influences Cytokine Production and Modulates Host Inflammatory Responses

The gastrointestinal tract encounters a wide variety of microorganisms, including beneficial symbionts, pathobionts, and pathogens. Recent evidence has shown that the gut microbiota, directly or indirectly through its components, such as metabolites, actively participates in the host inflammatory response by cytokine-microbiota or microbiota-cytokine modulation interactions, both in the gut and systemically. Therefore, further elucidation of host cytokine molecular pathways and microbiota components will provide a novel and promising therapeutic approach to control or prevent inflammatory disease and to maintain host homeostasis. The purpose of this review is to summarize well-established scientific findings and provide an updated overview regarding the direct and indirect mechanisms by which the gut microbiota can influence the inflammatory response by modulating the host's cytokine pathways that are mostly involved, but not exclusively so, with gut homeostasis. In addition, we will highlight recent results from our group, which suggest that the microbiota promotes cytokine release from inflammatory cells though activation of microbial metabolite sensor receptors that are more highly expressed on inflammatory and intestinal epithelial cells.

Renal Effects of Cytokines in Hypertension

Preclinical studies point to a key role for immune cells in hypertension via augmenting renal injury and/or hypertensive responses. Blood pressure elevation in rheumatologic patients is attenuated by anti-inflammatory therapies. Both the innate and adaptive immune systems contribute to the pathogenesis of hypertension by modulating renal sodium balance, blood flow, and functions of the vasculature and epithelial cells in the kidney. Monocytes/macrophages and T lymphocytes are pivotal mediators of hypertensive responses, while dendritic cells and B lymphocytes can regulate blood pressure indirectly by promoting T lymphocytes activation. Pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF), interleukin-1 (IL-1), interleukin-17 (IL-17), and interferon-γ (IFN), amplify blood pressure elevation and/or renal injury. By contrast, interleukin-10 (IL-10) protects against renal and vascular function when produced by T helper 2 cells (Th2) and regulatory T cells (Treg). Thus, understanding the renal effects of cytokines in hypertension will provide targets for precise immunotherapies to inhibit targeted organ damage while preserving necessary immunity.

Renal effects of cytokines in hypertension

PURPOSE OF REVIEW

Inflammatory cytokines contribute to the pathogenesis of hypertension through effects on renal blood flow and sodium handling. This review will update recent advances that explore the renal actions of immune cells and cytokines in the pathogenesis of hypertension.

RECENT FINDINGS

Populations of cells from both the innate and adaptive immune systems contribute to hypertension by modulating functions of the vasculature and epithelial cells in the kidney. Macrophages and T lymphocytes can directly regulate the hypertensive response and consequent target organ damage. Dendritic cells and B lymphocytes can alter blood pressure (BP) indirectly by facilitating T-cell activation. Proinflammatory cytokines, including tumor necrosis factor-α, interleukin 17, interleukin 1, and interferon-γ augment BP and/or renal injury when produced by T helper 1 cells, T helper 17 cells, and macrophages. In contrast, interleukin 10 improves vascular and renal functions in preclinical hypertension studies. The effects of transforming growth factor-β are complex because of its profibrotic and immunosuppressive functions that also depend on the localization and concentration of this pleiotropic cytokine.

SUMMARY

Preclinical studies point to a key role for cytokines in hypertension via their actions in the kidney. Consistent with this notion, anti-inflammatory therapies can attenuate BP elevation in human patients with rheumatologic disease. Conversely, impaired natriuresis may further polarize both T lymphocytes and macrophages toward a proinflammatory state, in a pathogenic, feed-forward loop of immune activation and BP elevation. Understanding the precise renal actions of cytokines in hypertension will be necessary to inhibit cytokine-dependent hypertensive responses while preserving systemic immunity and tumor surveillance.

Inhibiting Interleukin 17 Can Ameliorate the Demyelination Caused by A. cantonensis via iNOS Inhibition

Angiostrongylus cantonensis (A. cantonensis) is an important food-borne parasitic disease. Previous study showed that A. cantonensis infection can cause demyelination in the central nerve system, but the mechanism of action has not been understood. To explore the mechanism and to look for effective therapeutic methods, interleukin 17A (IL-17A) and iNOS expressions were detected during A. cantonensis infection. In addition, IL-17A-neutralizing antibody was applied to treat A. cantonensis-infected mice. In our results, we found that IL-17A and iNOS RNA expressions increased gradually in the process of A. cantonensis infection. When infected mice were treated with IL-17A-neutralizing antibody, the pathologic changes of demyelination alleviated obviously, followed with the elevation of myelin basic protein (MBP) in the brain. In addition, the iNOS expression of the brain in infected animals also showed a decrease in astrocytes. Our study provided evidence that IL-17A may take part in the demyelination caused by A. cantonensis and inhibiting IL-17A expression can ameliorate the pathologic changes of demyelination. Moreover, the decreasing of iNOS expression may be the key reason for the effect of IL-17A inhibition on demyelination caused by A. cantonensis.

Comparative health effects in mice of Libby amphibole asbestos and a fibrous amphibole from Arizona

This project developed from studies demonstrating that Libby Amphibole Asbestos (LAA) causes a non-typical set of health outcomes not generally reported for asbestos, including systemic autoimmunity and an unusual and devastating lamellar pleural thickening that progresses to severe pulmonary dysfunction and death. Further, mineral fiber mixtures with some similarities to LAA have recently been discovered in southern Nevada and northwestern Arizona, where the material exists in extensive recreational areas and is present in yards, roads, parking lots and school yards. The objective was to compare the health outcomes in mice exposed to either LAA or the fibrous amphiboles collected in Arizona at the Lake Mead National Recreational Area at very low doses to represent environmental exposures. In this study, the fibrous amphibole asbestos sample from Arizona (AzA) is composed of winchite (69%), actinolite (22%), and non-amphibole minerals (9%) and has a mean aspect ratio of 16.7±0.9. Fibrous amphibole asbestos from Libby (LAA) is composed of winchite (70%), richterite (9%), tremolite (5%), and non-amphibole minerals (16%) with a mean aspect ratio of 8.4±0.7. C57BL/6 mice were exposed by oropharyngeal aspiration to fiber suspensions at a very low dose of 3μg/mouse. After seven months, both LAA- and AzA-exposed mice had indices of chronic immune dysfunction related to a T_H17 cytokine profile, with B cell activation, autoantibody production and proteinuria, suggesting kidney involvement. In addition, both exposures led to significant lung and pleural fibrosis. These data suggest that there is risk of pulmonary disease and autoimmune outcomes with environmental exposure to amphibole asbestos, and that this is not limited to Libby, Montana.

Interleukin-17A is involved in mechanical hyperalgesia but not in the severity of murine antigen-induced arthritis

Interleukin-17A (IL-17A) is considered an important pro-inflammatory cytokine but its importance in joint diseases such as rheumatoid arthritis (RA) is unclear. It has also been reported that IL-17A may induce pain but it is unclear whether pro-inflammatory and pro-nociceptive effects are linked. Here we studied in wild type (WT) and IL-17A knockout (IL-17AKO) mice inflammation and hyperalgesia in antigen-induced arthritis (AIA). We found that the severity and time course of AIA were indistinguishable in WT and IL-17AKO mice. Furthermore, the reduction of inflammation by sympathectomy, usually observed in WT mice, was preserved in IL-17AKO mice. Both findings suggest that IL-17A is redundant in AIA pathology. However, in the course of AIA IL-17AKO mice showed less mechanical hyperalgesia than WT mice indicating that IL-17A contributes to pain even if it is not crucial for arthritis pathology. In support for a role of IL-17A and other members of the IL-17 family in the generation of pain we found that sensory neurones in the dorsal root ganglia (DRG) express all IL-17 receptor subtypes. Furthermore, in isolated DRG neurones most IL-17 isoforms increased tetrodotoxin- (TTX-) resistant sodium currents which indicate a role of IL-17 members in inflammation-evoked sensitization of sensory nociceptive neurones.

Novel therapies for immune-mediated inflammatory diseases: What can we learn from their use in rheumatoid arthritis, spondyloarthritis, systemic lupus erythematosus, psoriasis, Crohn's disease and ulcerative colitis?

The past three decades have witnessed remarkable advances in our ability to target specific elements of the immune and inflammatory response, fuelled by advances in both biotechnology and disease knowledge. As well as providing superior treatments for immune-mediated inflammatory diseases (IMIDs), such therapies also offer unrivalled opportunities to study the underlying immunopathological basis of these conditions.In this review, we explore recent approaches to the treatment of IMIDs and the insights to pathobiology that they provide. We review novel biologic agents targeting the T-helper 17 axis, including therapies directed towards interleukin (IL)-17 (secukinumab, ixekizumab, bimekizumab), IL-17R (brodalumab), IL-12/23p40 (ustekinumab, briakinumab) and IL-23p19 (guselkumab, tildrakizumab, brazikumab, risankizumab, mirikizumab). We also present an overview of biologics active against type I and II interferons, including sifalumumab, rontalizumab, anifrolumab and fontolizumab. Emerging strategies to interfere with cellular adhesion processes involved in lymphocyte recruitment are discussed, including both integrin blockade (natalizumab, vedolizumab, etrolizumab) and sphingosine-1-phosphate receptor inhibition (fingolimod, ozanimod). We summarise the development and recent application of Janus kinase (JAK) inhibitors in the treatment of IMIDs, including first-generation pan-JAK inhibitors (tofacitinib, baricitinib, ruxolitinib, peficitinib) and second-generation selective JAK inhibitors (decernotinib, filgotinib, upadacitinib). New biologics targeting B-cells (including ocrelizumab, veltuzumab, tabalumab and atacicept) and the development of novel strategies for regulatory T-cell modulation (including low-dose IL-2 therapy and Tregitopes) are also discussed. Finally, we explore recent biotechnological advances such as the development of bispecific antibodies (ABT-122, COVA322), and their application to the treatment of IMIDs.

Role of the Immune System in Hypertension

High blood pressure is present in more than one billion adults worldwide and is the most important modifiable risk factor of death resulting from cardiovascular disease. While many factors contribute to the pathogenesis of hypertension, a role of the immune system has been firmly established by a large number of investigations from many laboratories around the world. Immunosuppressive drugs and inhibition of individual cytokines prevent or ameliorate experimental hypertension, and studies in genetically-modified mouse strains have demonstrated that lymphocytes are necessary participants in the development of hypertension and in hypertensive organ injury. Furthermore, immune reactivity may be the driving force of hypertension in autoimmune diseases. Infiltration of immune cells, oxidative stress, and stimulation of the intrarenal angiotensin system are induced by activation of the innate and adaptive immunity. High blood pressure results from the combined effects of inflammation-induced impairment in the pressure natriuresis relationship, dysfunctional vascular relaxation, and overactivity of the sympathetic nervous system. Imbalances between proinflammatory effector responses and anti-inflammatory responses of regulatory T cells to a large extent determine the severity of inflammation. Experimental and human studies have uncovered autoantigens (isoketal-modified proteins and heat shock protein 70) of potential clinical relevance. Further investigations on the immune reactivity in hypertension may result in the identification of new strategies for the treatment of the disease.

Immunological dynamics associated with rapid virological response during the early phase of type I interferon therapy in patients with chronic hepatitis C

Type I interferons (IFNs) play an important role in antiviral immunity as well as immunopathogenesis of diverse chronic viral infections. However, the precise mechanisms regulating the multifaceted effects of type I IFNs on the immune system and pathological inflammation still remain unclear. In order to assess the immunological dynamics associated with rapid viral clearance in chronic hepatitis C patients during the acute phase of type I IFN therapy, we analyzed multiple parameters of virological and immunological responses in a cohort of 59 Korean hepatitis C patients who received pegylated IFN-α and ribavirin (IFN/RBV). Most of the Korean patients had favorable alleles in the IFN-λ loci for responsiveness to IFN/RBV (i.e., C/C in rs12979860, T/T in rs8099917, and TT/TT in rs368234815). Rapid virological response (RVR) was determined mainly by the hepatitis C virus genotype. Among the cytokines analyzed, higher plasma levels of IL-17A and FGF were observed in non-RVR patients infected with viral genotype 1 and IP-10 was consistently elevated in RVR group infected with genotype 2 during the early phase of antiviral therapy. In addition, these three cytokines were correlated each other, suggesting a functional linkage of the cytokines in antiviral responses during IFN/RBV therapy. A low baseline frequencies of regulatory T cells and γδ T cells, but high level of group 2 innate lymphoid cells, in peripheral bloods were also significantly associated with the RVR group, implicating a potential role of the cellular immunity during the early phase of IFN/RBV therapy. Therefore, the immunological programs established by chronic hepatitis C and rapid disruption of the delicate balance by exogenous type I IFN might be associated with the subsequent virological outcomes in chronic hepatitis C patients.

Inhibition of autoimmune Th17 cell responses by pain killer ketamine

Ketamine is widely used in animals and humans as a systemic anesthetic. Although several immune-modulatory functions of ketamine have been reported, the effects of ketamine on the differentiation of Th17 cell are unknown. We found that ketamine significantly diminished the frequency of IL-17-producers among CD4⁺ T cells stimulated under Th17-skewing conditions. Mechanistic studies showed that ketamine had little effect on the production of Th17-inducing cytokines by dendritic cells and the proliferation of T cells in response to anti-CD3; however it significantly hampered IL-21 expression as well as STAT3 phosphorylation in T cells upon IL-6 stimulation. Moreover, MOG-reactive CD4⁺ T cells expanded in the presence of ketamine produced reduced amounts of Th17 cytokines, leading to diminished EAE severity when transferred into TCRβ-deficient mice in comparison to those treated with vehicle. These findings demonstrate that ketamine suppresses autoimmune Th17 cell responses by inhibiting the differentiation as well as the reactivation of Th17 cells.

The relationship between circulating concentrations of interleukin 17 and C reactive protein in chronic spontaneous urticaria

Background

Up-regulation of interleukin 17 (IL-17) family cytokines and acute phase response have been observed in patients with chronic spontaneous urticaria (CSU). It has been demonstrated that IL-17 stimulates C-reactive protein (CRP) expression.

Aim

To determine relationship between circulating concentrations of IL-17 and CRP in CSU.

Methods

Concentrations of IL-17 in plasma and CRP in serum were measured in patients with CSU of varying severity and in the healthy subjects.

Results

IL-17 and CRP concentrations were significantly higher in CSU patients as compared to the healthy subjects. In addition, there were significant differences in IL-17 and CRP concentrations between CSU patients with mild, moderate-severe symptoms and the healthy subjects. CRP did not correlate significantly with IL-17.

Conclusions

Increased circulating IL-17 concentration may represent an independent index of systemic inflammatory response in CSU, which is not related to increased CRP concentration.