Figure 1. Gating strategy and test/retest reliability of stem and progenitor cell measurements by FACS analysis.

A) CD45⁺ cells were analyzed after doublet, debris, dead cell and red blood cell exclusion. The CD34⁺ cell fraction was then identified and further purified by removing any cells that express high levels of CD45 and low forward scatter properties. Expression of ALDH, CD133, and CD31 were then analyzed. This strategy is a modification of the previously published, widely used International Society for Hematotherapy and Graft Engineering gating strategy ²⁴. B) Coefficient of variation and correlation coefficients of the test/retest analysis of CD34⁺CD45^dimALDH⁺, CD34⁺CD45^dim, CD34⁺CD45^dimCD133⁺, and CD34⁺CD45^dimCD31⁺ SPC populations are listed.