THE REQUIREMENT OF ELECTROLYTES FOR THE ADSORPTION OF ESCHERICHIA COLI ANTIGEN BY RED BLOOD CELLS

Abstract

The role of electrolytes in the adsorption of E. coli serogroups 026, 055 and 0111 antigens was detd., and the following results were obtained. E. coli antigens are not adsorbed by red blood cells of sheep, man, rabbit, chicken and duck in the absence of electrolytes, i.e., when 5% glucose or 5% sucrose solns. are used as diluent. Lack of adsorption is evidenced by the fact that erythrocytes thus treated are not agglutinated specifically by homologous bacterial antiserum and, in the case of sheep cells, are neither agglutinated nor lysed. The supernatant fluid contains the unadsorbed antigen as shown by the observation that, on addition of NaCl, it modifies red blood cells for specific bacterial hemagglutination and hemolysis. Adsorption of the E. coli antigens by red blood cells takes place in the presence of suitable concns. of NaCl, KC1, CaCl2, and Na citrate. The lowest concns. of these electrolytes required for adsorption of the antigens for both minimal and optimal modification of red blood cells and thus for subsequent hemagglutination and hemolysis were detd. Within certain limits, the less antigen used for treatment of erythrocytes, the higher must be the concn. of the electrolytes. The requirement of electrolytes for adsorption by red blood cells of bacterial (E. coli) antigens parallels similar findings with certain viruses.