FIG. 6.

PVAT immune cells and atherosclerosis. There are various PVAT resident immune cells, including macrophages, DCs, T cells (such as Tc1, Th1, and Th17), and B cells. Inflammatory cytokines released from hypertrophic PVAT adipocytes promote macrophage (Φ) polarization to the M1 type, which further induces T cells and DCs to produce inflammatory cytokines, thereby causing a positive feedback loop for foam cell formation in the vascular wall. However, Treg can prevent macrophage infiltration and foam cell formation. In addition, resident IgM-producing B-1 cells prevent atherosclerosis development. Thus, the overall imbalance of immune cells in PVAT can drive atherosclerosis development. DC, dendritic cell; Treg, regulatory T cell. Color images are available online.