CD4+Foxp3+ regulatory T-cells (Tregs) are a unique subset of helper T-cells, which regulate immune response and establish peripheral tolerance. Tregs not only maintain the tone and tenor of an immune response by dominant tolerance but, in recent years, have also been identified as key players in resolving tissue inflammation and as mediators of tissue healing. Apart from being diverse in their origin (thymic and peripheral) and location (lymphoid and tissue resident), Tregs are also phenotypically heterogeneous as per the orientation of ongoing immune response. In this review, we discuss the recent advances in the field of Treg biology in general, and non-lymphoid and tissue-resident Tregs in particular. We elaborate upon well-known visceral adipose tissue, colon, skin, and tumor-infiltrating Tregs and newly identified tissue Treg populations as in lungs, skeletal muscle, placenta, and other tissues. Our attempt is to differentiate Tregs based on distinctive properties of their location, origin, ligand specificity, chemotaxis, and specific suppressive mechanisms. Despite ever expanding roles in maintaining systemic homeostasis, Tregs are employed by large varieties of tumors to dampen antitumor immunity. Thus, a comprehensive understanding of Treg biology in the context of inflammation can be instrumental in effectively managing tissue transplantation, autoimmunity, and antitumor immune responses.

BackgroundLittle work has been done on the prevalence of type 1 diabetes in north India. This paper reports the prevalence of type 1 diabetes in Karnal district of Haryana state, India.Materials and methodsPrevalence of type 1 diabetes was assessed by a hospital-based registry and by analysis of data contributed by chemists and other physicians.ResultsThe overall prevalence of type 1 diabetes in Karnal district is 10.20/100,000 population, with a higher prevalence in urban (26.6/100,000) as compared to rural areas (4.27/100,000). Karnal city, with a population of 222017, has a relatively high prevalence of type 1 diabetes (31.9/100,000). The prevalence in men is higher (11.56/100,000) than in women (8.6/100,000).In the 5 to 16 years age group, the prevalence is 22.22/100,000, while in the 0-5 years age group, prevalence is 3.82/100,000.ConclusionsThis report highlights the urban-rural and male-female gradient in the prevalence of type 1 diabetes in Karnal, north India.

ObjectiveIncreasing plasma levels and activity of dipeptidyl peptidase-4 (DPP4 or CD26) are associated with rapid progression of metabolic syndrome to overt type 2 diabetes mellitus (T2DM). While DPP4 inhibitors are increasingly used as anti-hyperglycemic agents, the reason for the increase in plasma DPP4 activity in T2DM patients remains elusive.MethodsWe looked into the source of plasma DPP4 activity in a cohort of 135 treatment naive nonobese (BMI < 30) T2DM patients. A wide array of ex vivo, in vitro, and in silico methods were employed to study enzyme activity, gene expression, subcellular localization, protease identification, surface expression, and protein–protein interactions.ResultsWe show that circulating immune cells, particularly CD4+ T cells, served as an important source for the increase in plasma DPP4 activity in T2DM. Moreover, we found kallikrein-related peptidase 5 (KLK5) as the enzyme responsible for cleaving DPP4 from the cell surface by directly interacting with the extracellular loop. Expression and secretion of KLK5 is induced in CD4+ T cells of T2DM patients. In addition, KLK5 shed DPP4 from circulating CD4+ T helper (Th)17 cells and shed it into the plasma of T2DM patients. Similar cleavage and shedding activities were not seen in controls.ConclusionsOur study provides mechanistic insights into the molecular interaction between KLK5 and DPP4 as well as CD4+ T cell derived KLK5 mediated enzymatic cleavage of DPP4 from cell surface. Thus, our study uncovers a hitherto unknown cellular source and mechanism behind enhanced plasma DPP4 activity in T2DM.

The GuideLiner mother-and-child catheter is a simple, safe and efficacious adjunctive device for difficult CTO PCIs where despite standard measures it is not possible to deliver an initial balloon or microcatheter across the occluded segment.

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