FURTHER OBSERVATIONS ON MATUHASI-OGATA PHENOMENON

Summary. When a specific antigen‐antibody complex is formed another antibody present at the same time, or introduced to the complex subsequently, can attach to and be eluted from the complex although the antigen to which it is directed is not present. This nonspecific binding of antibody, the Matuhasi‐Ogata phenomenon, has been examined in a series of 45 experiments and has been shown to occur independently of temperature, the strength or specificity of any of the antibodies involved or red cell individuality. The phenomenon is important: in the preparation of blood typing antisera; in the interpretation of antibody significance in eluates from persons with a positive direct antiglobulin test; in the separation, by absorption and elution procedures, of antibodies in multispecific sera; and in the detection of weak isoagglutinins in sensitized patients. © 1969 Blackwell Publishing Ltd