T cell-derived extracellular vesicles are elevated in essential HTN

Extracellular vesicles (EVs) are novel mediators of cell-to-cell communication and appear to mediate the pathogenesis of hypertension (HTN). However, the mechanisms underlying the involvement of EVs in HTN remain unclear. The adaptive and innate immune systems play an important role affecting the kidney and vasculature in animal models of HTN. Evolving evidence shows that immune cell-derived EVs can modulate the immune system in a paracrine fashion and therefore may mediate the effects of inflammation in the pathogenesis of HTN. Therefore, we aimed to understand if specific subtypes of leukocyte/immune cell-derived EVs are altered in essential HTN using an in vivo model of angiotensin II (ANG II)-induced HTN. After 4 wk of ANG II treatment, EVs were isolated from the blood and kidney. EV origin and counts were characterized with Imaging Flow Cytometry, antibody panels targeting platelets, endothelial cells, and leukocytes including B and T cells, monocytes, and neutrophils. Leukocyte-derived EVs (CD45⁺) were elevated in the circulation and kidney tissue in ANG II-induced HTN. Subgroup analysis depicted T cell-derived EVs (CD3⁺) to be significantly elevated in ANG II-induced HTN (3.50e⁺⁵ particles/mL) compared with control groups (9.16e⁺⁴ particles/mL, P = 0.0106). T cell-derived EVs also significantly correlated with systolic blood pressure levels (r² = 0.898, P = 0.0012). In summary, leukocyte-derived EVs, and more specifically T cell-derived EVs (CD3⁺), are elevated in ANG II-induced HTN in the circulation and kidney tissue and correlate well with blood pressure severity. EVs from the circulation and kidney may be sensitive biomarkers for HTN and end-organ damage and may lead to new mechanistic insights in this silent disease.