Figure 9. Angiogenic function of Rgs2 in MDSC is mediated through MCP-1.
(A) and (B) Wild type and Rgs2−/− MDSCs were isolated from 3LL tumor tissues by magnetic sorting, and incubated overnight at 37°C. 80,000 HUVECs were plated in each well of a 48-well plate on top of Matrigel in the conditioned medium derived from the isolated MDSCs. Representative images are shown at 72 hours, and Vascular network branch points were scored at the times indicated. This experiment was performed in duplicate and repeated twice. (C) MDSCs were isolated from tumors of Rgs2−/− and wild type mice by magnetic sorting, and incubated overnight. Transwells containing 1×105 HUVECs in the top chamber were added and allowed to migrate for 3.5 hours. MCP-1 neutralizing antibody (Ab) (1 ug/ml) was added to wild type cells or 1 ng/ml of recombinant MCP-1 was added to Rgs2−/− cells. This experiment was performed 3 times in duplicate. * p≤0.05, ** p<0.005, *** p<0.001, **** p<0.00005.