Relationship between Flk1⁺, CD41⁺, proximal-hCD4⁺, and distal-GFP⁺ cells. (A-C) FACS profiles of Flk-1, proximal-hCD4, CD41, and distal-GFP expression in populations P1 to P3 sorted from day 3 EBs, analyzed at the day of sort (left), after 1 day of reaggregation (middle), and after 2 days of reaggregation (right). (D) Not-sorted day 3 EB cells FACS analyzed for expression of Flk-1, proximal-hCD4, CD41, and distal-GFP at day 0 (presort) and after reaggregation for 1 or 2 days. Numbers indicate percentages of respective populations.