Further studies on the isotope modification of the mixed hemadsorption technique. Factors influencing the prozone effect.

Abstract

The reaction patterns, especially the prozone effect, obtained by the isotope modification of the mixed hemadsorption technique (IMHT) were analyzed with reference to dependence on various factors. The results indicated that the prozone effect in IMHT was related to the relative concentrations of cross‐bridging antibody molecules on indicator and target cells This ratio seemed to have an optimum at which the reactivity was maximal. The existence of such an optimal ratio with regard to the concentrations of cross‐bridging antibody molecules presumably accounts for the previously noted different tendencies to prozone effect of different antigen‐antibody systems The results and indirect evidence suggested that the prozone effect is independent of the antigenic distribution on the cell membrane as influenced by antibody‐mediated redistribution of cell surface antigens. The high sensitivity of IMHT enabled studies of the rate of disappearance of membrane‐bound antibody where this was not possible by other methods.