A mechanism for the induction of type 2 immune responses by a protease allergen in the genital tract

Inflammatory cytokine signalling in vulvovaginal candidiasis: a hot mess driving immunopathology

Protective immunity to opportunistic fungal infections consists of tightly regulated innate and adaptive immune responses that clear the infection. Immune responses to infections of the vaginal mucosa by Candida species are, however, an exception. In the case of vulvovaginal candidiasis (VVC), the inflammatory response is associated with symptomatic disease, rather than that it results in pathogen clearance. As such VVC can be considered an inflammatory disease, which is a significant public health problem due to its predominance as a female-specific fungal infection. Particularly, women with recurrent VVC (RVVC) suffer from a significant negative impact on their quality of life and mental health. Knowledge of the inflammatory pathogenesis of (R)VVC may guide more effective diagnostic and therapeutic options to improve the quality of life of women with (R)VVC. Here, we review the immunopathogenesis of (R)VVC describing several elements that induce an inflammatory arson, starting with the activation threshold established by vaginal epithelial cells that prevent unnecessary ignition of inflammatory responses, epithelial and inflammasome-dependent immune responses. These inflammatory responses will drive neutrophil recruitment and dysfunctional neutrophil-mediated inflammation. We also review the, sometimes controversial, findings on the involvement of adaptive and systemic responses. Finally, we provide future perspectives on the potential of some unexplored cytokine axes and discuss whether VVC needs to be subdivided into subgroups to improve diagnosis and treatment.

Investigation of the frequency and relationship between trichomonas infection in the preterm delivery (a case-control study in Amir Al-Momenin Hospital, Semnan)

Introduction and Purpose

Preterm delivery is a common complication during pregnancy periods and imposes a high cost on the healthcare system due to the care needs of premature babies. Sexually transmitted infections are one of the effective factors in the occurrence of preterm delivery and the diagnosis and treatment of these infections are effective in reducing complications and preventing preterm delivery. In this study, the role of Trichomonas vaginalis (T. vaginalis [TV]) infection in preterm delivery has been evaluated.

Methods

In a prospective case-control study, women with preterm birth were assigned to the case group, and women with full-term delivery on the same day were also assigned randomly to the control group. After receiving the history and physical examination, a sample was taken from the cervix for TV culture. The data were included in the SPSS version 23 software. A significance level of less than 0.05 was considered.

Findings

The overall prevalence of this infection was 10%. The prevalence of chlamydial infection was 2% among mothers with full-term delivery and 16.4% among mothers with premature birth, and there was a significant difference between the two groups (P = 0.021). The logistic regression analysis to determine the effect of Trichomonas infection on premature birth showed that there was the probability of the occurrence of premature delivery increases in mothers with trichomoniasis infection with lower age, higher body mass index, the presence of underlying disease, lower educational level, housewives, lower parity and gravity and having a history of fetus abortion more than 13 times with its occurrence probability occurs in mothers without Trichomonas infection (P = 0.046, Exp (β) =13.266).

Conclusion

According to the present results, TV screening for pregnant women, especially in high-risk groups, is emphasized to reduce the incidence of preterm delivery and related complications, especially neonatal complications.

A case of complete recovery in a hypereosinophilic dermatitis patient with dupilumab

BACKGROUND

Hypereosinophilic dermatitis (HED) is a subtype of hypereosinophilic syndrome (HES). Glucocorticoids are preferred for treatment but carry substantial side effect profiles. Symptoms of HED may recur after systemic glucocorticoid tapering. As an interleukin-4 receptor (IL-4Rα) monoclonal antibody targeting interleukin-4 (IL-4) and interleukin-13 (IL-13), dupilumab might be an efficacious adjuvant therapy for HED.

METHOD

We report a young male diagnosed with HED who suffered from erythematous papules with pruritus for over five years. Once reducing the dosage of glucocorticoid was, his skin lesions relapsed.

RESULTS

After using dupilumab, the patient's condition significantly improved with the glucocorticoid dosing decreased successfully.

CONCLUSION

In conclusion, we report a new application of dupilumab in HED patients, especially with difficulties in reducing the glucocorticoid dose.

Hapten sensitization to vaginal mucosa induces less recruitment of dendritic cells accompanying TGF-β-expressing CD206+ cells compared with skin

INTRODUCTION

Contact hypersensitivity (CHS), a type of delayed-type hypersensitivity, is induced by hapten exposure to the skin and mucosa. We previously reported that, in a murine model of CHS, the vaginal mucosa (VM) sensitization showed lower T-cell responses as compared with the abdominal skin sensitization. To investigate mechanisms of impaired CHS by the VM sensitization, we compared migration of hapten-captured dendritic cells (DCs) in the draining lymph nodes (dLNs) and recruitment of DCs at the sensitized local sites.

METHODS

Fluorescein isothiocyanate (FITC) or 2,4-dinitrofluorobenzene (DNFB) was used as hapten, and migration of FITC+ DCs in the dLNs and local recruitment of MHC class II+ and CD11c+ cells were compared between abdominal skin and VM sensitization by flow cytometric analyses and immunohistochemistry. Expression of tumor growth factor (TGF)-β at mRNA and protein levels, and local recruitment of CD206+ cells were examined after VM sensitization.

RESULTS

VM sensitization showed less numbers of FITC+ MHC class IIhigh CD11c+ migratory DCs in the dLNs at 6 and 24 h, as compared with skin sensitization. Both skin and VM sensitization induced the recruitment of dermal/submucosal DCs at 6 h, but the number of submucosal DCs in the VM was significantly decreased at 24 h. VM showed persistently higher mRNA levels of TGF-β2/β3 expression than those of the skin before and after sensitization. In the VM sensitization, increment of CD206+ MHC class II+ cells was observed especially at the deep lamina propria at 24 h. Most of CD206+ cells were also positive for the binding to Fc chimeric TGF-β receptor that interacts with all TGF-β isoforms, suggesting TGF-β expression.

CONCLUSION

DC migration to dLNs and localization of DCs at the sensitized sites are limited in the VM sensitization. Our results suggest that the existence of TGF-β-expressing CD206+ cells may contribute less sensitization ability and CHS responses in the VM.

Il4ra-independent vaginal eosinophil accumulation following helminth infection exacerbates epithelial ulcerative pathology of HSV-2 infection

How helminths influence the pathogenesis of sexually transmitted viral infections is not comprehensively understood. Here, we show that an acute helminth infection (Nippostrongylus brasiliensis [Nb]) induced a type 2 immune profile in the female genital tract (FGT). This leads to heightened epithelial ulceration and pathology in subsequent herpes simplex virus (HSV)-2 infection. This was IL-5-dependent but IL-4 receptor alpha (Il4ra) independent, associated with increased FGT eosinophils, raised vaginal IL-33, and enhanced epithelial necrosis. Vaginal eosinophil accumulation was promoted by IL-33 induction following targeted vaginal epithelium damage from a papain challenge. Inhibition of IL-33 protected against Nb-exacerbated HSV-2 pathology. Eosinophil depletion reduced IL-33 release and HSV-2 ulceration in Nb-infected mice. These findings demonstrate that Nb-initiated FGT eosinophil recruitment promotes an eosinophil, IL-33, and IL-5 inflammatory circuit that enhances vaginal epithelial necrosis and pathology following HSV-2 infection. These findings identify a mechanistic framework as to how helminth infections can exacerbate viral-induced vaginal pathology.

Impact of Helminth Infections on Female Reproductive Health and Associated Diseases

A growing body of knowledge exists on the influence of helminth infections on allergies and unrelated infections in the lung and gastrointestinal (GI) mucosa. However, the bystander effects of helminth infections on the female genital mucosa and reproductive health is understudied but important considering the high prevalence of helminth exposure and sexually transmitted infections in low- and middle-income countries (LMICs). In this review, we explore current knowledge about the direct and systemic effects of helminth infections on unrelated diseases. We summarize host disease-controlling immunity of important sexually transmitted infections and introduce the limited knowledge of how helminths infections directly cause pathology to female reproductive tract (FRT), alter susceptibility to sexually transmitted infections and reproduction. We also review work by others on type 2 immunity in the FRT and hypothesize how these insights may guide future work to help understand how helminths alter FRT health.

Interleukin (IL)-33: an orchestrator of immunity from host defence to tissue homeostasis

Interleukin (IL)-33, a member of the IL-1 superfamily, functions as an alarm signal, which is released upon cell injury or tissue damage to alert the immune system. It has emerged as a chief orchestrator in immunity and has a broad pleiotropic action that influences differentiation, maintenance and function of various immune cell types via the ST2 receptor. Although it has been strongly associated with immunopathology, critically, IL-33 is involved in host defence, tissue repair and homeostasis. In this review, we provide an overview of the signalling pathway of IL-33 and highlight its regulatory functions in immune cells. Furthermore, we attempt a broader discussion of the emerging functions of IL-33 in host defence, tissue repair, metabolism, inflammatory disease and cancer, suggesting potential avenues to manoeuvre IL-33/ST2 signalling as treatment options.

IRF4 and STAT3 activities are associated with the imbalanced differentiation of T-cells in responses to inhalable particulate matters

Background

Particulate Matter (PM) is known to cause inflammatory responses in human. Although prior studies verified the immunogenicity of PM in cell lines and animal models, the effectors of PM exposure in the respiratory system and the regulators of the immunogenicity of PM is not fully elucidated.

Methods

To identify the potential effector of PM exposure in human respiratory system and to better understand the biology of the immunogenicity of PM, We performed gene-expression profiling of peripheral blood mononuclear cells from 171 heathy subjects in northern China to identify co-expressed gene modules associated with PM exposure. We inferred transcription factors regulating the co-expression and validated the association to T-cell differentiation in both primary T-cells and mice treated with PM.

Results

We report two transcription factors, IRF4 and STAT3, as regulators of the gene expression in response to PM exposure in human. We confirmed that the activation of IRF4 and STAT3 by PM is strongly associated with imbalanced differentiation of T-cells in the respiratory tracts in a time-sensitive manner in mouse. We also verified the consequential inflammatory responses of the PM exposure. Moreover, we show that the protein levels of phosphorylated IRF4 and STAT3 increase with PM exposure.

Conclusions

Our study suggests the regulatory activities of IRF4 and STAT3 are associated with the Th17-mediated inflammatory responses to PM exposure in the respiratory tracts, which informs the biological background of the immunogenicity of particulate matters.

Multivalent DNA vaccine protects against genital herpes by T-cell immune induction in vaginal mucosa

Genital herpes is one of the most common sexually transmitted infections (STIs), and it is mainly caused by the neurotropic herpes simplex virus (HSV-2). Not only does this infection cause ulcers, but HSV-2 can also stay in a latent state in the nervous system of the host throughout their lifespan. As a result, many people do not know that they harbor this infection. Moreover, HSV-2 serves as a major risk factor for human immunodeficiency virus (HIV) infection and can be transmitted to the fetus. Despite the high risk of infection and adverse effects, attempts at development of an effective vaccine for HSV-2 have not yet been successful. In this study, we developed a DNA vaccine for HSV-2 (SL-V20). This multivalent DNA vaccine effectively reduced the pathological symptoms of infection and induced efficient elimination of the virus in a mouse model. Intramuscular injection of SL-V20 led to induction of an HSV-2-specific T-cell response in the vagina, the major infection site, and in draining lymph organs. Dendritic cells (DCs), especially basic leucine zipper ATF-like transcription factor 3 (Baft3)⁺ DCs and partially interferon regulatory factor 4 (Irf4)⁺ DCs, were involved in this T-cell-mediated protective response, while B cells were dispensable for these prophylactic effects. This study demonstrates that SL-V20 offers a novel and effective vaccine against vaginal HSV-2 infection and may be applicable to patients, pending validation in clinical studies.

Increased intracellular Cl- concentration mediates Trichomonas vaginalis-induced inflammation in the human vaginal epithelium

Trichomonas vaginalis is a primary urogenital parasite that causes trichomoniasis, a common sexually transmitted disease. As the first line of host defense, vaginal epithelial cells play critical roles in orchestrating vaginal innate immunity and modulate intracellular Cl^- homeostasis via the cystic fibrosis transmembrane conductance regulator (CFTR), an anion channel that plays positive roles in regulating nuclear factor-κB (NF-κB) signalling. However, the association between T. vaginalis infection and intracellular Cl^- disequilibrium remains elusive. This study showed that after T. vaginalis infection, CFTR was markedly down-regulated by cysteine proteases in vaginal epithelial cells. The intracellular Cl^- concentration ([Cl^-]_i) was consequently elevated, leading to NF-κB signalling activation via serum- and glucocorticoid-inducible kinase-1. Moreover, heightened [Cl^-]_i and activated NF-κB signalling could be sustained in a positive feedback regulatory manner resulting from decreased intracellular cAMP through NF-κB-mediated up-regulation of phosphodiesterase 4. The results conclusively revealed that the intracellular Cl^- of the human vaginal epithelium could be dynamically modulated by T. vaginalis, which contributed to mediation of epithelial inflammation in the human vagina.

The Role of Skin and Orogenital Microbiota in Protective Immunity and Chronic Immune-Mediated Inflammatory Disease

The skin and orogenital mucosae, which constitute complex protective barriers against infection and injuries, are not only the first to come into contact with pathogens but are also colonized by a set of microorganisms that are essential to maintain a healthy physiological environment. Using 16S ribosomal RNA metagenomic sequencing, scientists recognized that the microorganism colonization has greater diversity and variability than previously assumed. These microorganisms, such as commensal bacteria, affect the host’s immune response against pathogens and modulate chronic inflammatory responses. Previously, a single pathogen was thought to cause a single disease, but current evidence suggests that dysbiosis of the tissue microbiota may underlie the disease status. Dysbiosis results in aberrant immune responses at the surface and furthermore, affects the systemic immune response. Hence, understanding the initial interaction between the barrier surface immune system and local microorganisms is important for understanding the overall systemic effects of the immune response. In this review, we describe current evidence for the basis of the interactions between pathogens, microbiota, and immune cells on surface barriers and offer explanations for how these interactions may lead to chronic inflammatory disorders.

R-Ras deficiency does not affect papain-induced IgE production in mice

Introduction

R‐Ras GTPase has recently been implicated in the regulation of immune functions, particularly in dendritic cell (DC) maturation, immune synapse formation, and subsequent T cell responses.

Methods

Here, we investigated the role of R‐Ras in allergen‐induced immune response (type 2 immune response) in Rras deficient (R‐Ras KO) and wild type (WT) mice.

Results

Initially, we found that the number of conventional DC's in the lymph nodes (LNs) was reduced in R‐Ras KO mice. The expression of co‐stimulatory CD80 and CD86 molecules on these cells was also reduced on DC's from the R‐Ras KO mice. However, there was no difference in papain‐induced immune response between the R‐Ras WT and KO as measured by serum IgE levels after the immunization. Interestingly, neither the DC number nor co‐stimulatory molecule expression was different between WT and R‐Ras KO animals after the immunization.

Conclusions

Taken together, despite having reduced number of conventional DC's in the R‐Ras KO mice and low expression of CD80 on DC's, the R‐Ras KO mice are capable of mounting papain‐induced IgE responses comparable to that of the WT mice. To our knowledge, this is the first report addressing potential differences in in vivo allergen responses regulated by the R‐Ras GTPase.