A Simple Hemagglutination System Requiring Small Amounts of Red Cells and Antibodies

A method is described which permits dilute red cell suspensions (1/32%) to be used in plastic microtiter plates for detecting hemagglutinins at unusually high dilutions. The use of suitable additives to the hemagglutination mixture enables excellent settling patterns and a high sensitivity to be obtained. Direct agglutination, inhibition, enzyme promoted agglutination, and Coombs tests can all be performed. Quantitative studies demonstrate the discriminatory powers of the technic. The method may be useful for economizing in the consumption of reagents in blood grouping.