Monoclonal antibodies to high‐incidence Kell epitopes: characterization and application in automated screening of donor samples

SUMMARY. Monoclonal antibodies, LM313/706 and LM357/828, recognize high-frequency epitopes which are absent on red cells of Ko phenotype. Both antibodies have proved suitable for automated screening of blood donor samples, with 5 ml of each culture supernatant sufficient to screen 3,000 donor samples. In a screen of 45,545 samples, LM313/706 revealed 11 samples (1: 3686) of Kp(a + b-) phenotype. Thirty-seven samples of K + k- phenotype were identified in 15,235 samples screened with LM357/828 antibody (0.24%). The epitope recognized by LM313/706 was inactivated by 2mm DTT suggesting a possible association with the Jsa/Jsb antigen structure. The expression of the k-like epitope detected by LM357/828 antibody was found to be influenced by pH change.