Tregs have been studied in clinical practice for different therapeutic applications. In the past several years there has been a significant interest in the transplant community to develop tolerance in order to substantially decrease or even eliminate the need of immuno-suppressive regimens. A growing body of evidence recognizes the balance between graft-reactive effector cells and graft-protective suppressor Treg cells as the ultimate determinant of long-term allograft survival. As a result, there is a major interest in transplantation to enhance the suppressor immune response as an alternative or complementary approach to reach a clinical tolerogenic state and preserve graft function. Exercise improves baseline immune function and helps to maintain immune homeostasis. Treg cell numbers have shown to increase with physical activity, and this increment has been directly correlated with exercise intensity. These results suggest that the increased Treg frequency may contribute to the beneficial effects of exercise on disorders associated with autoimmune disease or chronic low-grade inflammation such as atherosclerosis, diabetes mellitus, chronic kidney disease or cancer.~Primary Objectives: The overall purpose of this study is to determine the influence High-intensity interval training (HIIT) on the frequency and quality of peripheral Treg cells.~Secondary Objectives: Effects of HIIT in other T cell populations. Effects of HIIT in plasma concentration of inflammatory and metabolic markers. Effects of HIIT in obese vs lean.~Design: This is a prospective, single center, single-arm pre-test/post-test study designed to evaluate the safety, feasibility and initial efficacy of a 12-week HIIT regimen to increase the frequency and quality of peripheral Treg cells. All participants will have a pre-test (baseline) evaluation followed by a treatment and then a post-test.
Regulatory T cells (Tregs) are a small population of T cells compromising of 1% to 5% of the total T cells in the body but they are playing a fundamental role in the maintenance of the immune homeostasis. These cells modulate the immune system by suppressing the effector activity and thus preventing autoimmune diseases and chronic inflammatory processes. Treg cell numbers have shown to increase with physical activity, and this increment has been directly correlated with exercise intensity. These results suggest that the increased Treg frequency may contribute to the beneficial effects of exercise on disorders associated with autoimmune disease or chronic low-grade inflammation such as atherosclerosis, diabetes mellitus, chronic kidney disease or cancer.~The overall purpose of this study is to determine the influence High-intensity interval training (HIIT) on the frequency and quality of peripheral Treg cells.