A Thermostable Antigen in Beef-Cells

Abstract

Bailey and Raffel 1 showed that serums from 3 patients with infectious mononucleosis contained lysins for beef-cells in addition to agglutinins and lysins for sheep-cells.∗ Serums from 22 cases of infectious mononucleosis examined by us showed the presence of beef-cell lysins in dilutions from 1:1280 to 1:20480, much higher than the titer for sheep-cell lysins. Beef-cell agglutinins were not present in any of the 22 serums in a concentration exceeding that in normal serum. In this respect the antigen responsible for the beef-cell antibodies in infectious mononucleosis acts like a true Forssman antigen in that high lytic titers are produced with little or no corresponding agglutinins.

It has been shown that both raw and boiled beef- and sheep-cells adsorb the beef-lysins of infectious mononucleosis 1 and we have amply confirmed this fact. The presence of a thermostable antigen in the beef-cell, in which no heterophile antigen has yet been demonstrated, needs further investigation. Accordingly the relationship of the beef-cell lysins of infectious mononucleosis serum to the alcoholic extracts and alcohol-treated sheep- and beef-cells previously described 2 was determined. The anticomplementary action of the extracts was controlled with pure isophile beef-serum prepared by adsorbing rabbit antibeef-cell serum with raw sheep-cells. The possibility of hemolysis by the complement must not be overlooked in testing for beef lysins. The complement from 25 of 43 guinea pigs had to be discarded because of the presence of normal beef-lysins in dilutions of 1:10 to 1:100. Sheep-lysins were also present in 1:40 dilution in the serum of 2 animals. These antibodies were not adsorbed by boiled beef-cells, which indicates their isophile nature.