Functional capacities of tetC^HIGH, tetC^INT, and tetC^NEG PC subsets. (A-C) Left panels show a representative histogram of APO2.7 expression (A) and activated caspase-3 expression after a 24-hour culture period (B), and BrdU uptake after an 18-hour incubation period (C), by the 3 blood PC subsets. The corresponding bar histograms on the right summarize the results obtained from several donors. Values are expressed as the MFI of the expression of positive PCs (A,B) and as the percentage of positive PCs (C). Results represent the mean plus or minus SEM (n = 5 for panels A-C). (D) Recovery of tetC^NEG, tetC^INT, and tetC^HIGH PCs in blood cell cultures. The percentage of tetC^NEG, tetC^INT, and tetC^HIGH PCs recovered initially (0 hours), and after 24 and 48 hours of culture, were determined by flow cytometry. Results represent the mean plus or minus SEM (n = 6). (E) CXCL12-induced chemotaxis of tetC^NEG, tetC^INT, and tetC^HIGH PCs. CXCL12 (1 μg/mL) was added to the bottom chamber of a transwell culture system. Values are expressed as the percentage of migrated PCs. Results represent the mean plus or minus SEM (n = 6). Asterisks in panels A through C indicate statistically significant differences among PC subsets, and in panels D and E indicate statistically significant differences within every PC subset among data from different times (D) or from different experimental conditions (E).