Figure 3

SDF-1 improves cardiac mesoangioblast migration through CD44, MMPs and cav-1. (a) Cardiac mesoangioblasts pretreated with different cytokines (50 ng/ml IL8 and SDF-1; 80 ng/ml MCP-1; 30 ng/ml TNF-α; 30 ng/ml FGF) were plated on endothelium-coated filters and induced to migrate for 6 h in the presence of mature cardiomyocytes in the lower chamber. FGF was used as a positive control. One representative out of five independent experiments run in duplicate is shown (left; ^*α<0.01). A representative image of the transmigrated SDF-1-pretreated cardiac mesoangioblasts is also shown (right). Bar, 30 μm. (b) GFP-cardiac mesoangioblasts pretreated with 50 ng/ml SDF-1 were injected into the LV chamber of control or CAL mice, and after 6 h, the heart and filter organs were analyzed by real-time PCR for the presence of migrated cells (^*α<0.03, ⁺α<0.02). (c) A gene array containing oligos corresponding to different mouse adhesion molecules was hybridized with cDNAs probes retrotranscribed from RNA of cardiac mesoangioblasts pretreated with SDF-1. Relative RNA levels of selected mRNAs normalized to β-actin expression are shown. Data presented are the mean of two independent experiments (^*α<0.01). (d) SDF-1-pretreated cardiac mesoangioblasts were incubated with the MMP inhibitor, GM1489 or siRNA cav-1 inhibitor or with Abs against CD44 and αv integrin and induced to migrate for 6 h through endothelium-coated filters and in the presence of mature cardiomyocytes in the lower chamber. A representative out of three independent experiments run in duplicate is shown (^*α<0.02,⁺α<0.005)