IMMUNOCHEMICAL STUDIES ON BLOOD GROUP SPECIFICITY

I. PARTIAL PURIFICATION AND PROPERTIES OF PLANT AGGLUTININ (LECTIN) OF SOPHORA JAPONICA

Abstract

It has been known for many years that there exist hemagglutinins in the seeds of many plants, particularly in those of Leguminosae, but those were in general recognized as non-specific substance to blood group antigens and, in consequence, did hardly attract attention of many researchers. In 1948, Renkonen 1) discovered firstly the natural antibodies being completely specific to blood group antigens in certain seeds and described the significance of plant agglutinin as one source of blood group antibodies. In 1953, Morgan and Watkins 2) reported the inhibiting effect of some simple sugars on the reaction between red blood cell and plant agglutinins. This important finding gave us a clue to illustrate the blood group specificity from a standpoint of chemical structure. In this decade, a number of new plant agglutinins were discovered 3-5) and partial purification of several plant agglutinins were made 6-8), but no report on the details of their chemical properties and compositions has been found. We are now working with the purification of plant agglutinin of Sophora japonica in order to get any knowledge on its chemical properties and composition and finally to elucidate the mechanisms of its selectivity to blood group antigens. In this paper, we shall present the method of partial purification of agglutinin and some of its properties.