Isolation of AC133⁺ and AC133⁻subsets from human embryonic tissues.

Human fetal neural cells were stained with human-specific antibodies raised to the prominin AC133, CD34, and CD45. AC133⁺ and AC133⁻ cells were isolated according to sorting gates shown in Figure 1, from the population of cells devoid of CD34 and the hematopoietic marker CD45. (A) Purified subpopulations of AC133⁺CD34⁻CD45⁻ (Bi) and AC133⁻CD45⁻CD34⁻ (Bii) cells from human neural tissue were cultured under serum-free conditions shown to induce neural hematopoiesis. Magnification × 200 (Bi) and × 400 (Bii). Hematopoietic colonies of multiple lineages were detected from AC133⁺CD34⁻CD45⁻ cells. The composition of colonies was similar to that shown in Figure 4. (C) Quantitative analysis of hematopoietic colonies arising from either AC133⁺ or AC133⁻ subsets from the CD34⁻CD45⁻ population. Cells were cultured in HGF with BMP-4 and EPO and were then collected and plated into colony-forming assays. Colonies were scored after 12 to 14 days and shown as the average number of colonies per 50 000 cell input ± SEM. Averages shown are based on 4 independent samples.