The effects of the wild-type and chimeric chemokines on CFU-A colony growth. All chemokines and chimeras were tested at 100 ng/mL (final concentration) by direct addition to the assay plates. In this assay, the average number of CFU-A colonies per control plate was 9.0 ± 1.8. Results are expressed as a percentage of CFU-A colony growth plus or minus SEM, with the mean number of colonies on control plates representing 100%. For statistical comparison, ns indicates not significant; ^*P < .005; and ^**P < .001. This assay is representative of 3 repeat assays.