Activated STING in the thymus alters T cell development and selection leading to autoimmunity.

Classifying systemic inflammatory disorders as autoinflammatory or autoimmune provides insight into disease pathogenesis and whether treatment should target innate molecules and their signaling pathways or the adaptive immune response. COPA syndrome is a monogenic disorder of immune dysregulation that leads to interstitial lung disease and high-titer autoantibodies. Studies show constitutive activation of the innate immune molecule STING is centrally involved in disease. However, the mechanisms by which STING results in loss of T cell tolerance and autoimmunity in COPA syndrome or more common autoimmune diseases is not understood. Using CopaE241K/+ mice, we uncovered a functional role for STING in the thymus. Single cell data of human thymus demonstrates STING is highly expressed in medullary thymic epithelial cells (mTECs) involved in processing and presenting self-antigens to thymocytes. In CopaE241K/+ mice, activated STING in mTECs triggered interferon signaling, impaired macroautophagy and caused a defect in negative selection of T cells. Wild-type mice given a systemic STING agonist phenocopied the selection defect and showed enhanced thymic escape of a T cell clone targeting a self-antigen also expressed in melanoma. Our work demonstrates STING activation in TECs shapes the T cell repertoire and contributes to autoimmunity, findings important for settings that activate thymic STING.

Clinical significance of blocking novel immune checkpoint B7-H4 in urothelial carcinoma of bladder as a potential therapeutic target.

Urothelial Carcinoma of Bladder is complex disease with high mortality and recurrence rates. Current standard regimes have exhibited anti-tumor activity but still, a proportion of patients are non-responsive or in-eligible to receive such treatments. Immune checkpoints have emerged as potential class of therapeutics to be tested in UCB patients. Clinical trials targeting PD-1/PD-L1 axis have been tested in UCB but still a proportion of patients are non-responsive to it which stresses upon identifying new targets. New immune checkpoint B7-H4 has been shown to negatively regulate T cell activity in cancer and is a poor prognostic factor in various solid tumors. In this study we assessed the novel immune checkpoint B7-H4 status in UCB patients. We observed elevated expression of B7-H4 and PD-L1 on CD8+ T cells in circulation of UCB patients. Relative mRNA expression and immunohistochemistry displayed upregulation in bladder tumor tissue. Increased expression of B7-H4 along with PD-L1 in periphery and tumor of UCB patients highlights involvement of B7-H4 in disease progression. Combinatorial blocking of B7-H4 and PD-L1 enhanced IFN-γ and granzyme B in CD8+ T cells functional T cell immune response in UCB patients. Also, B7-H4 was significantly associated with clinico-pathological parameters. Our findings highlight B7-H4 as potential therapeutic target for treatment of UCB patients in future after further validation.

Association of human papillomavirus in penile cancer: A single-center analysis.

Introduction: Human papillomavirus (HPV) is a known risk factor of penile cancer (PeCa). However, studies evaluating its true association are limited. In this study, we aimed to estimate HPV prevalence and its true association with PeCa in terms of molecular biological activities. Materials and Methods: This single-institutional prospective observational study was conducted between June 2016 and August 2019. We included 40 men with PeCa as a study group and 20 age-matched uncircumcised men who underwent circumcision for phimosis as a control group. Both the groups underwent deoxyribonucleic acid isolation for HPV subtyping followed by evaluation of relative E6/E7 messenger ribonucleic acid (mRNA) expression profile and relative telomerase activity in tissue samples. HPV-16 and -18 were categorized as high-risk, whereas HPV-6 and -11 were categorized as low-risk subtypes. Results: The mean (±standard deviation) age of PeCa was 51 ± 15.9 years. The majority of patients had stage II disease, and the most common procedure done was partial penectomy. The overall prevalence of HPV in PeCa was 42.5% (n = 17) as compared to 20% (n = 4) in controls. Among the subtypes, the most common subtype was HPV-16 noted in 33.3% (8/24) of cases, followed by HPV-18 in 29.2% (7/24) of cases. PeCa tissues had a significantly higher relative E7 mRNA expression for HPV-18 than the control group (P = 0.016). The mean relative telomerase activity was significantly higher in the PeCa tissues than the control group (138.66 vs. 14.46, P < 0.001). A significantly higher relative telomerase activity was noted in the PeCa tissues positive for high-risk HPV subtypes than controls (141.90 vs. 14.46, P = 0.0008), but not between high-risk HPV-positive and HPV-negative PeCa cases (141.90 vs. 137.03, P = 0.79). High-risk subtypes were not associated with tumor stage (P = 0.76) or lymph node metastasis (P = 0.816). Conclusions: HPV was associated in 42.5% of PeCa cases based on our experience from a single institution. PeCa tissues had a higher relative E7 mRNA expression for HPV-18 and relative telomerase activity as compared to controls suggesting their potential role as surrogate markers of virus-induced tumorigenesis.

Dendritic cells and their associated pro-inflammatory cytokines augment to the inflammatory milieu in vitiligo skin.

BACKGROUND AND AIM: Vitiligo is a progressive, autoimmune, hypomelanotic acquired disorder of skin which is characterized by depigmentation. The initial immunological events of this diseases are still at enigma that includes breach of immune tolerance, and defect in antigen presentation. Hence, we aimed to explore role of Dendritic cells (DCs) and its associated cytokines in the pathogenesis of generalized vitiligo (GV) patients. METHODOLOGY: For this case-control study, 20 active patients and controls were enrolled. Phenotypic characterization of myeloid and plasmacytoid DCs (mDCs, pDCs) were done by flow-cytometry. Primary culture of DCs was done by monocyte differentiation supplemented with rIL-4 and rGM-CSF. Functional analysis DCs related cytokines and co-stimulatory molecules (CD80, CD40) was done by ELISA and qPCR respectively. Tissue localization of DCs was evaluated by immunohistochemistry. RESULT: The frequency of mDCs (0.3715% v/s 0.188%) and pDCs (0.2331% v/s 0.1156%) were elevated in patients as compared to controls. Circulatory level of IL-12, TNF-α were significantly higher whereas IFN-α was decreased in patients than controls. Similar results were obtained in the culture supernatants of patients. Relative mRNA expression profiling of co-stimulatory molecules (CD80, CD40) were found to be up regulated in patient's skin. Tissue localization of Langerhans cells (Langerin, CD1a+) were found to be significantly higher in patients. CONCLUSION: Elevated frequency of mDCs and pDCs along with elevated levels of IL-12, TNF-α and CD80, CD40 may contribute in defective antigen presentation of DCs. Altered pro-inflammatory and anti-inflammatory cytokines along with tissue localization of Langerhans cells might be involved in the pathogenesis of GV. These DCs associated cytokines can be explored as a therapeutic target in future.

Systemic dissemination of tumor cells during transurethral resection in patients with bladder tumor and its clinical relevance: A follow up study.

OBJECTIVE: Tumor cells are shed during transurethral resection of bladder tumor (TURBT) and form the basis for use of single dose immediate chemotherapy instillation to reduce recurrences. Systemic dissemination of these cells along with the irrigation fluid is also possible but not consistently proven. In this study, we evaluated such dissemination of tumor cells into the circulation during TURBT and its clinical impact. METHODS: Patients with primary presentation of bladder tumor who underwent TURBT were included. Peripheral venous blood samples before and after TURBT were analyzed for circulating tumor cells (CTCs) using flow-cytometry. A CD45 negative cell with positive expression of cytokeratin 18, 19, and EpCam was defined as CTC. The CTC counts, pre and post TURBT, were compared and correlated with final histopathology. The patients were also followed up for any local and/or systemic recurrences. RESULTS: Nine (16.98%) out of 53 patients developed a measurable rise in CTCs after TURBT. All of these patients had high grade and muscle invasive disease. Overall, a measurable rise in CTCs was seen in 9 out of 17 (52.94%) patients with muscle invasive disease. There was no difference in the clinico-pathological stage or the status of cystectomy and/or chemotherapy between those who did or did not show a rise in CTCs. On follow up, 7 patients with muscle invasive disease developed local and/or systemic recurrences and the rise in CTCs was not found to be associated with adverse oncological outcomes. CONCLUSIONS: This study confirms the hypothesis of inadvertent dissemination of tumor cells into the circulation during TURBT, especially in patients with high grade and muscle invasive disease. The long-term oncological impact of such dissemination remains to be confirmed.

Elevated IL-6R on CD4+ T cells promotes IL-6 driven Th17 cell responses in patients with T1R leprosy reactions.

Th17 cells play vital role during pathogenesis of leprosy reactions. Previously, we have reported that IL-23 is involved in Th17 cells differentiation. Subsequently, our group also showed that IL-6 induces Th17 cell differentiation along with TGF-ß in leprosy reactions. Here, we next asked the question that whether IL-6 or IL-23 induced Th17 cells are different in nature? In this study, Type 1 Reactions (T1R) showed significantly (p < 0.001) higher percentage of IL-17A producing CD4+IL6R+ T cells as compared to non-reaction (NR) patients. Furthermore, recombinant IL-6, IL-23 and TGF-ß promoted IL-17A secretion by CD4+IL6R+ T cells. Subsequently, IL-6R and IL-23R blocking experiments showed significantly (p < 0.002) down regulated IL-17A in T1R reaction as compared to NR leprosy patients. The present study for the first time establishes that pathogenic Th17 cells produce IL-17 in an IL-6 dependent manner in leprosy T1R reactions. Thus, present approaches that specifically target Th17 cells and/or the cytokines that promote their development, such as IL-6, TGF-ß and IL-23A may provide more focused treatment strategies for the management of Mycobacterium leprae and its reactions.

Emerging role of immune cell network in autoimmune skin disorders: An update on pemphigus, vitiligo and psoriasis.

Autoimmune skin diseases are a group of disorders that arise due to a deregulated immune system resulting in skin tissue destruction. In the majority of these conditions, either autoreactive immune cells or the autoantibodies are generated against self-antigens of the skin. Although the etiology of these diseases remains elusive, biochemical, genetic, and environmental factors such as infectious agents, toxins damage the skin tissue leading to self-antigen generation, autoantibody attack and finally results in autoimmunity of skin. Immune dysregulation, which involves predominantly T helper 1/17 (Th1/Th17) polarization and the inability of regulatory T cells to regress immune response, is implicated in autoimmune skin diseases. The emerging roles of immune cells, cytokines, and chemokines in the pathogenesis of common autoimmune skin diseases like pemphigus, vitiligo, and psoriasis are discussed in this review. The main focus is on the interplay between immune cell network including the innate and adaptive immune system, regulatory cells, immune checkpoints and recently identified tissue-resident memory cells (TRMs) in disease pathogenesis and relapse. We also attempt to highlight on the immune mechanisms common to these diseases which can be targeted for designing novel therapeutics.

Interleukin-10 Producing Regulatory B Cells Transformed CD4+CD25- Into Tregs and Enhanced Regulatory T Cells Function in Human Leprosy.

Regulatory B cells (Bregs) are known to exhibit their regulatory functions through interleukin-10 (IL-10) cytokine which suppress inflammation. There are only a few studies explaining the phenotype and functioning of these cells in contribution to host immunity in leprosy. Here, we evaluated the role of IL-10 producing Bregs in the pathogenesis of leprosy and assessed their immunoregulatory effects on Tregs and effector T cells. We found an increased frequency of Bregs and increased expression of their immune modulatory molecules (IL-10, FoxP3, and PDL-1) in leprosy patients. The potential immunoregulatory mechanism of Bregs was also investigated using MACS sorted Teff (CD4+CD25-) and Treg (CD4+CD25+) cells were cocultured with Bregs to elucidate the effects of Bregs on effector T and regulatory T cells. Cell coculture results showed that purified Bregs cells from leprosy patients convert CD4+CD25- cells into CD4+CD25+ cells. Cell coculture experiments also demonstrated that leprosy derived IL-10 producing Bregs enhance FoxP3 and PD-1 expression in Tregs and enhanced Tregs activity. Blocking of IL-10 receptor confirmed that IL-10 producing Breg has immunomodulatory effect on Tregs and effector T cells as effector T cells are not converted into Tregs and enhanced expression of FoxP3 and PD-1 was not observed on Tregs. Collectively, these findings demonstrate that IL-10 producing Breg cells play an important mechanism in controlling the immunopathogenesis of leprosy and have an immunomodulatory effect on Tregs and effector T cells. Our findings may pave way for novel targets of IL-10 producing Bregs for immunotherapy in leprosy patients.

Weekly iron folic acid supplementation plays differential role in maintaining iron markers level in non-anaemic and anaemic primigravida: A randomized controlled study.

Anaemia during pregnancy is most commonly observed and highly prevalent in South-East Asia. Various effective programmes have been laid down for its management, mainly daily supplementation of iron folic acid (IFA) tablets. Following the same, standard obstetrical practice has included the IFA supplementation without requiring the determination of iron deficiency. In this study, a total of 120 primigravida (N = 60; non-anaemic (Hb > 11 g/dl) and N = 60 anaemic (Hb = 8-11 g/dl)) were selected among those attending the Antenatal Clinic in Department of Obstetrics and Gynaecology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India. They were supplemented with daily and weekly IFA tablets till 6 weeks postpartum. Corresponding changes in haemoglobin level on advance of pregnancy, side effects and compliance associated with daily and weekly IFA supplementation and its associations with iron status markers were studied. The inflammatory markers were also estimated. The statistical significance level (p < 0.05) between the groups were assessed by applying unpaired t-test using SPSS (version 16.0). The obtained results publicized the salutary role of daily IFA supplementation in improving the haemoglobin level and iron status markers in anaemic pregnant women though the levels could not reach up to the non-anaemic haemoglobin levels. However, weekly IFA supplementation seems to be a better approach in non-anaemic pregnant women where almost comparable results were obtained in terms of haematological parameters, gestation length and birth weight. CONCLUSION: Weekly IFA supplementation found to be as effective as daily supplementation in iron sufficient non-anaemic pregnant women whereas anaemic pregnant women should be prescribed daily IFA supplementation irrespective of iron replete/deplete state.