Comparative analysis of the changes in human cell yield provoked by the addition of rhSDF-1α protein or anti-CXCR4 mAbs to FTOC established with either CD34⁺ cells or immature CD4⁺ thymocytes.

SCID thymic lobes were seeded with either highly purified CD34⁺ (white bars) or CD4⁺ immature thymocytes (black bars) and organ cultured for 10 or 18 days in the presence of either rhSDF-1α protein or anti-CXCR4 mAbs. At each time point, cells were harvested and counted. Numbers of human cells were calculated by multiplying the total number of cells per lobe by the percentage of human CD45-FITC⁺ cells determined by flow cytometric analysis. The bars represent the mean of 3 independent experiments. SDs represented less than 18% of the mean values. Results are expressed as the percentage of values from the control FTOC. Control values are represented as 0.