An Agglutination Reaction Observed with Some Human Bloods, Chiefly Among Negroes

Abstract

In an attempt to produce immune sera for the human blood property (1) designated as P two batches of 12 rabbits each were injected with the blood of individuals known to give strong reactions for P. The first batch received blood of the type O, M, N of a white man L. F., the second that of a Negro C. H. (O, N), the latter having been used for the preparation of anti-P-serum once before. The animals received several courses of six daily injections of 0.1 to 0.4 cc. washed blood cells in a volume of 1 cc. The courses were separated by rest periods of eight days; a fourth course of injections was given ten weeks after the third. From the first lot of rabbits, after three courses of injections, one P serum of moderate strength and two rather weak sera were obtained.