E-selectin inhibits proliferation and induces apoptosis of mouse HPCs. (A) Adhesion of murine BM lineage^neg Sca-1⁺ c-KIT⁺ (LSK) cells to immobilized BSA, rmu P-selectin (1800 sites/μm²), or rmu E-selectin (550 sites/μm²). (B) Proliferation of murine BM LSK cells grown in the presence of cytokine combinations 11FTS, 36GS, or 3611FTS on microwells coated with BSA, P-selectin, or E-selectin. Cells were seeded at 10⁴/mL and counted after 7 days incubation in serum-deprived medium. (C) Apoptosis of murine BM LSK cells cultured 7 days in the presence of 11FTS, 36GS, or 3611FTS on microwells coated with BSA, P-selectin, or E-selectin. (D) Pre–colony-forming cell assay. Bone marrow LSK cells were cultured in the presence of 11FTS, 36GS, or 3611FTS on microwells coated with BSA, P-selectin, or E-selectin. After 7 days incubation, cells were transferred to fresh noncoated wells and cultured an additional 7 days before colony assays were performed. The results are expressed as the number of colonies derived from a single original LSK cell. The clonogenic efficiencies (expressed as a percentage) of the cells put into methylcellulose are indicated above each column. *Statistically different (P < .05) from BSA treated control groups. Results are expressed as mean ± SEM of 3 (D) or 5 (A-C) independent experiments made in triplicate.