GMP-grade CD34 selection from HLA-homozygous licensed cord blood units and short-term expansion under European ATMP regulations.

Background: Based on a synergistic consortium, the cord blood (CB) bank Düsseldorf was responsible for the selection of HLA-homozygous (HLA-h) donors, contacting/re-consenting the mothers, Good Manufacturing Practice (GMP)-grade CD34 enrichment, followed by short-term expansion of CD34 cells and qualification of the resulting CD34 population as advanced therapy medicinal product (ATMP)-starting material. Among 20 639 licensed Düsseldorf cord blood units (CBUs), 139 potential HLA-h donors were identified with the most frequent 10 German haplotypes. 100% of the donors were contacted, and for 47·5%, consent was obtained.