Use of stroma for the detection of blood-group antibodies by ELISA.

A micro enzyme-linked immunosorbent assay (ELISA), using lyophilized stroma as carrier of red blood cell antigens, which stay stable longer than usual, using intact erythrocytes, was developed for determination of blood-group antibodies in the AB0, Kell and Lewis-systems. Stroma being fixed on microtiter plates was incubated with antisera and peroxidase-conjugated anti-human globulin. The transformation of the substrate added was determined photometrically. A binding of antibodies to the stroma could be demonstrated up to an antibody dilution of 1:1024 for the ABO-system, of 1:512 for the Kell-system and of 1:64 for the Lewis-system. By standardization of this method the quantitative determination of antibodies becomes possible without being restricted by the limited stability of intact erythrocytes.