Figure 6.

 Altered growth factor responsiveness of SHIP^−/− CFC. Bone marrow derived from wild type (– –), heterozygous (– . –), or null (—) littermates was plated in methylcellulose containing the indicated concentrations of (A) GM-CSF, (B) IL-3, (C) Steel factor, or (D) M–CSF. Colonies of >20 cells were scored on day 10 of culture and the numbers of colonies present at each cytokine concentration were calculated as the percent of the number formed in the highest concentration of the cytokine indicated. Values represent the mean ± s.e.m. for duplicate determinations using at least three mice per group. Statistical significance compared to +/+ littermates was determined using the Student’s t-test. P ≤ 0.05 (*); P ≤ 0.008 (***).