CFC content in 100 fresh, Day 0, (n=6) or the equivalent of 100 Rho^lo cells after 35 days of culture (n=8). The frequency of LT-CRSC of freshly purified Rho^lo cells, 1 in 14, compared to the frequency of CAFC, 1 in 13±1.7 (n=11), after 28-35 days culture on AFT024. Limiting-dilution CRSC and CAFC frequency was determined by Poisson statistics at 37% negative mice or wells. Rho^lo cells from the same purification were used to determine both CRSC and CAFC frequencies. %Ly5.2 peripheral blood cells from 25 Day 0 Rho^lo cells (n=5) compared to the 35 day cultured equivalent of 25 Rho^lo cells (n=5) from the same purification; both transplanted in CRSC assay.