STUDIES ON MIXED AGGLUTINATION WITH SPECIAL REFERENCE TO THE A ANTIGEN AND THE PHYSICAL PROPERTIES OF THE OPERATIVE ANTIBODIES.

Abstract

Differences in reactions in the mixed agglutination test with anti-A sera from different individuals were found to be unrelated to the titre against human or pig A red cells or simply to the presence or absence of either 7S or 19S antibody. It was found that 7S anti-A was capable of producing mixed agglutination, but that 19S fractions more frequently produced mixed agglutination than the 7S fraction from the same serum. Treatment of sera with 2-mercapto-ethanol abolished the capacity to produce mixed agglutination from some sera, whilst other sera were unaffected. Some anti-A sera gave the same titre of mixed agglutination with both secretor and non-secretor buccal cells, but other sera reacted more strongly with secretor than with non-secretor cells. Production of mixed agglutination by 7S antibodies was also demonstrated with fractions of rabbit antisera against Forssman antigen and against bovine red cells.