Further studies on hybrid cell-surface antigens associated with human chromosome 11

A new human immunogenetic cell-surface activity associated with human chromosome 11 in the A_L human-Chinese hamster ovary cell hybrid is described. Like a₁ but not a₂, it is present on the human erythrocyte. By mutagenesis and selection, specific, stable, variants of the A_L hybrid have been prepared exhibiting various combinations of a₁ a₂, a₃, and lactic dehydrogenase A activities. The antigens of the A_L system can be demonstrated by the horseradish peroxidase system which offers a promising approach to scanning of tissue cells.