ZZAP treatment of red blood cells.

CONCLUSIONS: ZZAP is a mixture of a sulfhydryl reagent (dithiothreitol) and a proteolytic enzyme (papain or ficin). This reagent dissociates IgG and complement from red blood cells, allowing for phenotyping, enhanced adsorption, or denaturing of multiple blood group system antigens to aid in completing complex antibody workups. ZZAP treatment destroys all antigens in the Kell, Landsteiner- Wiener, Cartwright, Dombrock, and Knops blood group systems as well as antigens destroyed by proteases (e.g., M, N, S, Fya, and Fyb).