A simple solid-phase method for the identification of red cell-bound antibodies without elution.

The authors have developed a solid-phase direct hemadherence assay (SPDHA) to identify red cell-bound antibody without elution. The procedure of SPDHA is as follows: (1) commercially available panel cells were immobilized on the well of microplane; (2) 22% polymerized albumin and 0.3% test red cells were added, and the plate was centrifuged at low speed, and incubated; (3) finally the plate was centrifuged, and the results were read macroscopically. SPDHA could detect antibodies against D, C, c, E, e, Fya, Fyb, K, k, A and B antigens. The sensitivity of SPDHA was high in Rh antibodies as compared with that in the other antibodies. SPDHA failed to detect anti-Jka, -Jkb, -S, -s and -Dia antibodies. In cases of suspected hemolytic disease of newborn, Rh antibodies could be identified using very small volume of red cells. In conclusion, SPDHA is a useful and simple method to identify red cell-bound antibodies, especially when only a small volume of red cell sample is available, such as the sample from fetus or newborn.