Flow cytometry shows the expression of kinin receptors on freshly isolated PB-MNCs, CD133+, and CD34+ progenitors, as well as cultured EPCs of healthy human subjects. A, B2R is highly abundant in progenitor CD133+ and CD34+ cell fractions as compared with total MNCs, whereas B1R expression is low in the studied cell populations. B and C, Reverse gating shows that in the B2R+ MNC fraction, CD133+ and CD34+ progenitors (B) coexpressing KDR and CXCR4 (C) are more abundant. D, Consistently, outgrowth of acLDL+UEAI+ EPCs is more frequent from FACS sorted B2R+ PB-MNCs. Values are means±SEM; n=6 to 15. **P<0.01.