CD4 and obesity due to melanocortin 4 receptor deficiency: The growing recognition of lymphocyte (T cell) infiltration into adipose tissue in obesity and the role of adaptive immunity in obesity-induced inflammation [27,71,72] indicates the need for future studies to employ flow cytometry to further distinguish the effects of n3-PUFAs on the infiltration of specific T-cell subtypes, since others have shown increased total T cells (CD3+), T helper cells (CD3+CD4+), and cytotoxic T cells (CD3+CD8+) in the visceral adipose tissue of mice with diet-induced obesity [42].