CD4 and type 2 diabetes mellitus: In patients with Type 2 diabetes, black tea consumption was associated with increased regulatory T cells (CD3+ CD4+ CD25+ FOXP3) and immunosuppressive CD3+ CD4+ IL-10+ cells, alongside reduced proinflammatory CD3+ CD4+ IL-17+ cells and Th1-associated CD3+ CD4+ IFN-γ+ cells [57].