Expansion of baboon CD34⁺ cells and progenitor cells in PMVEC coculture. Bone marrow CD34⁺cells from two baboons were immunomagnetically selected using the MoAb K6.1 and used to inoculate 10-day expansion cultures in coculture with the porcine microvascular endothelial cell line PMVEC in the presence of exogenous human SCF, IL-3, IL-6, and GM-CSF. The total number of CD34⁺ cells (dots), CFU-GM (vertical lines), and CAFC (diagonal lines) were determined flow cytometrically, by methylcellulose culture, and by limiting-dilution assay on murine stromal fibroblasts, respectively, at inoculation (day 0) and at harvest (day 10) immediately before infusion into the animals.