IL-10 enhances the M-CSF–dependent growth of human monocytes. Monocytes (8.8 × 10⁴) in 24-well tissue culture plates were incubated with increasing concentration of M-CSF (12.5 to 100 ng/mL) in the presence or absence of IL-10 (10 ng/mL) for 7 days. The recovered cells were counted using cetrimide as described in Materials and Methods. Data are expressed as the mean of triplicated wells (+SD) from a representative experiments of three performed.