STUDIES ON LEWIS BLOOD GROUP ANTIGENENS OF RED CELLS AND PLASMA

Abstract

1) Frequency of Lewis blood groups was studied in bloods from nonpregnant controls (male adults) and from pregnant women. Incidence of groups Le (a+b-), Le (a-b+) and Le (a-b-) among 1058 nonpregnants was 22.8%, 70.8% and 6.4%, whereas that among 1072 pregnant women was 20.3%, 54.6% and 25.1% respectively. The increased incidence of group Le (a-b-) and the decreased incidence of group Le (a-b+) among pregnant women were demonstrated.2) Lewis active glycolipid was eluted from red cells after the incubation with pH 5.0 buffered saline. The supernatant of hemolyzed red cells had stronger Lewis activity than the red cell ghost.3) Lewis active glycolipid which was extracted from red cells and plasma, and was fractionated by silicic acid column chromatography showed slower mobility on thin layer chomatography than those from red cells obtained by the elution at pH 5.0 and from plasma glycolipid treated at pH 5.0. The Lewis active glycolipid extracted from red cells and plasma may be complex of glycolipid and lipid or glycolipid and protein. The conversion of red cells of group Le (a-b-) into groups Le (a+b-) and Le (a-b+) were demonstrated by incubation of red cells with the Lewis active glycolipid, while the transformation did not occur by incubation of red cells with intact plasma from groups Le (a+b-) and Le (a-b+).4) Absorption of the Lewis active glycolopid on red cells was inhibited by the presence of lipoprotein of plasma. It is probable that the failure of the conversion of Lewis negative red cells into Lewis positive cells by the intact plasma is depending on the quantity of plasma lipoprotein in Japanese which is higher level that in Caucasians.