Data represented as total amount of cytokine produced (A) in pg/ml per 105 T cells in blood, spleen, aorta, kidney and brain (n?=?7C11). The levels of the chemokine, CCL2, following anti-CD3 stimulation were also measured using a CBA (Fig. analysis of amount of IL-6 produced following anti-CD3/CD28 stimulation using a CBA. Data represented as total amount of IL-6 produced in pg/ml per 105 T cells in blood, spleen, aorta, kidney and brain (n?=?11C22).(TIFF) pone.0114895.s004.tiff (600K) GUID:?A62EF322-29FD-4460-8D17-86B2DF785523 S5 Figure: IL-10 production from blood and organ-isolated T cells. Quantitative analysis of amount of IL-10 IU1-47 produced following anti-CD3/CD28 stimulation using CBA assay. Data represented as total amount of IL-10 produced in pg/ml per 105 T cells in blood, spleen, aorta and kidney (n?=?11C22).(TIFF) pone.0114895.s005.tiff (431K) GUID:?8DBCBAC7-4D92-41C5-8D03-096860E6127A Data Availability StatementThe authors confirm that all data underlying the findings are fully available without restriction. All relevant data are within the paper and its Supporting Information files. Abstract Hypertension remains the leading risk factor for cardiovascular disease (CVD). Experimental hypertension is associated with increased T cell infiltration into blood pressure-controlling organs, such as the aorta and kidney; importantly in absence of T cells of the adaptive immune system, experimental hypertension is significantly blunted. However, the function and phenotype of these T cell infiltrates remains speculative and undefined in the setting of hypertension. The current study compared T cell-derived cytokine and reactive oxygen species (ROS) production from normotensive and hypertensive mice. Splenic, blood, aortic, kidney and brain T cells were isolated from C57BL/6J mice following 14-day vehicle or angiotensin (Ang) II (0.7 mg/kg/day, s.c.) infusion. T cell infiltration was increased in aorta, kidney and brain from hypertensive mice. Cytokine analysis in stimulated T IU1-47 cells indicated an overall Th1 pro-inflammatory phenotype, but a similar proportion (flow cytometry) and quantity (cytometric bead array) of IFN-, TNF-, IL-4 and IL-17 between vehicle- and Ang II- treated groups. Strikingly, elevated T cell-derived production of a chemokine, chemokine C-C motif ligand 2 (CCL2), was observed in aorta (6-fold) and kidney in response to Ang II, but not in brain, spleen or blood. Moreover, T cell-derived ROS production in aorta was elevated 3 -fold in Ang II-treated mice (n?=?7; P<0.05). Ang II-induced hypertension does not affect the overall T cell cytokine profile, but enhanced T cell-derived ROS production and/or leukocyte recruitment due to elevated CCL2, and this effect may be further amplified with increased infiltration of T cells. We have identified a potential hypertension-specific T cell phenotype that may represent a functional contribution of T cells to the development of hypertension, and likely several other associated vascular disorders. Introduction Hypertension is a common risk factor for cardiovascular disease and stroke, which are the major causes of morbidity and mortality in Western societies (W.H.O, 2013) . While current anti-hypertensive therapies can maintain blood pressure homeostasis in some patients, surprisingly 10C15% of cases of human hypertension remain resistant to these therapies, whether used alone or in combination , . Moreover, despite extensive research, the etiology of hypertension still remains unclear and novel approaches need to be developed to treat this condition. Recent studies have implicated inflammation and activation of the immune system in the development of hypertension . It is now well defined that T cells are required for the development of hypertension, which infiltrate organs that control blood pressure such as the aorta and kidneys , . However, the functional contribution of these infiltrating T cells to the local inflammatory response during hypertension remains PVR speculative and understudied. T lymphocytes can be divided into several subtypes and subsets that all produce various responses to infection and immune homeostasis. The predominant subtypes are T helper (Th) IU1-47 cells (CD4+) and cytotoxic T cells (CD8+), but a population of double negative cells also exist (DN; CD4-CD8-). Approximately 95% of all T cells express a membrane-bound T cell receptor (TCR) comprised of and subunits, which is capable of recognizing specific antigens IU1-47 presented in the context of a major histocompatibility complex. A smaller population of T cells (5C10%) express a different TCR comprised of and subunits that recognize antigens that are usually not presented by MHC molecules. Antigen presenting cells such as dendritic cells and macrophages engulf foreign antigens and can present antigen-specific epitopes to T cells. In the presence of innate cytokines such as IL-12/IFN-, IL-4 and IL-23, Th cells (CD4+) polarise to Th1, Th2 and Th17 cells respectively . Polarised Th subsets secrete adaptive immune cytokines that also include IFN-, TNF- (both Th1), IL-4 (Th2) and IL-17 (Th17), which mount an immune response involving reciprocal activation of.