Figure 3.

Treg in angiogenesis. Treg can promote angiogenesis under hypoxic or hyperglycaemic conditions. The main source of VEGFA for tumour angiogenesis in ovarian cancer cell lines is from recruited Treg, and VEGFA promotes the expansion of CD31⁺ endothelial cells. Treg also promotes angiogenesis in ischaemic hindlimb through the release of IL-10, although the mechanism remains unknown. IL-10 released by Treg also improves hindlimb ischaemia in hyperglycaemia, and both IL-10 and AREG can promote angiogenesis. IL-10 is demonstrated to promote the proliferation of CD31⁺ endothelial cells under hyperglycaemic conditions, although the mechanism for AREG in inducing angiogenesis remains unknown.