A monolayer coagglutination microplate technique for typing red blood cells.

BACKGROUND AND OBJECTIVES Serologic agglutination tests have the disadvantage of lack of an objective endpoint that can be easily read and quantitated. We have developed a new method for ABO and Rh typing based on producing a red blood cell (RBC) monolayer on microplates and the mixed hemagglutination reaction. MATERIALS AND METHODS We have employed a new red cell fixation buffer to prepare the RBC monolayer. As the technique for grouping, we used a mixed agglutination reaction between the RBC monolayer and the RBCs to be typed. RESULTS Compared with an automated hemagglutination system in 34,519 samples, the method is shown to be more sensitive, free of false positive reactions, and cost-effective. CONCLUSIONS The microplate coagglutination method is accurate and lower in cost than conventional methods.