The internal image-like anti-idiotypic response to a CD3-specific monoclonal antibody in primates is dependent on the T cell-binding properties of the injected antibody.

Murine monoclonal antibodies used for therapeutic purposes generally elicit a strong antibody response. A large proportion of this response is specific for the idiotype of the injected monoclonal antibody. The CD3 T cell antigen is polymorphic in rhesus monkeys. A monoclonal antibody, FN18, which detects this polymorphism was used to analyze the immune response to FN18 in FN18+ and FN18- animals. The results of this study show that the internal image-like anti-idiotypic response predominantly occurs in FN18+ animals. This suggests that this type of anti-idiotypic response is limited to cell-binding monoclonal antibodies.