KLF10−/− CMP- and GMP-derived PACs possess markedly reduced migratory function and release of soluble paracrine factors. (A) The indicated WT or KLF10−/− BM-derived PACs were assayed for adhesion on fibronectin-coated plates. The number of adherent cells was quantitated after 15 minutes (n = 6 per group). *P < .01 versus WT; **P < .05 versus WT. (B) The indicated WT or KLF10−/− BM-derived PACs were assayed using a modified Transwell Boyden chamber in response to serum. The number of cells in the lower chamber was quantitated after 4 hours (n = 6 per group). *P < .01 versus WT. (C) Cell surface expression of the chemokine receptors CXCR4, CXCR3, and CCR7 was determined on the indicated WT or KLF10−/− BM-derived PACs by flow cytometry and expressed as percentage of positivity. (D) The indicated WT or KLF10−/− BM-derived PACs were assayed with a modified Transwell Boyden chamber in response to 1% BSA control or the chemokines SDF-1α, CXCL10, or CCL21. The number of cells in the lower chamber was quantitated after 4 hours (n = 6 per group). *P < .01 versus WT; **P < .05 versus WT. (E) Culture supernatants were harvested from the indicated WT or KLF10−/− CMP- and GMP-derived PACs assessed by ELISA for the indicated cytokines, growth factors, or chemokines (n = 3 per group). *P < .01 versus WT.