HA-1^H specific elimination of human umbilical cord blood and bone marrow derived hematopoietic progenitor/stem cells by HA-1 CTLs studied in vitro.

<p>(A-F) Umbilical cord blood (UCB) derived CD34+ and bone marrow (BM) derived CD34⁺ and CD133⁺ cells from HLA-A2/HA-1^H or HLA-A2/HA-1^RR donors were incubated with medium, an irradiated control CMV CTL clone, an HA-1 CTL clone or an anti-HLA-A2 specific CTL clone overnight. Data are mean +/- Standard deviation of independent experiments with 3 HA-1^H and 2 HA-1^RR donors, respectively (*p<0,05; **p<0.01, ns = not significant using a two-tailed Student’s t-test). The results of the medium control were set as 100%. (A, D) % viable CD34⁺ or CD133⁺ cells (duplicate sample per donor) compared to the medium control directly after over-night co-incubation with CTLs. (B, E) % colony forming cells (single sample per donor) compared to the medium control as determined after 14 days; CFU-macrophage (CFU-M; striped bar), CFU-Granulocyte (CFU-G; black bar), blast forming unit (BFU-E; white bar). (C, F) % of cobblestone area positive wells (4–5 samples per donor) in a CAFC assay compared to the medium control as determined after 5 weeks. (G-H) An HA-1 CTL clone was titrated to BM derived CD34+ cells (white bars), UCB derived CD34+ cells (grey bars) and to BM derived CD133⁺ cells (black bars) from HLA-A2/HA-1^H donors and co-incubated over night. x-axis: HA-1 CTL to CD34 or CD133 cell ratio. Y-axis: % viable CD34⁺ or CD133+ cells (duplicate sample per donor) compared to the medium control (G) and % of cobblestone area positive wells in a CAFC assay (4–5 samples per donor) compared to the medium control as determined after 5 weeks (H).