FACS-based separation of cells of 2 donors by HLA mAbs and verification by qPCR analysis. (A) Flow cytometric analysis. Monoclonal Abs MCA2090 (anti-HLA-A2) and HDG8D9 (anti-HLA-B51/B35) were used for cell sorting. Graph denotes 100 000 cells analyzed by the FACS in the 0.1% cell mixture. (B) Presort samples and sorted samples were processed for qPCR analysis of the reference gene HCK, the chimeric DNA markers DYZ1 and HLA-DRB1*04, and the background DNA marker HLA-DRB1*16. Bars show means ± SD of 3 separate experiments. Dotted bars, presort samples; shaded bars, positive fractions after sorting; open bars, negative fractions after sorting.