Abstract: | Heterologous anti-rabbit IgG antisera have been examined by radioimmunoassay for the occurrence of anti-VH antibody. Most of the sera contained antibody specific for VH allotype determinants (Aal). The antisera contained as much or more anti-al antibody as estimated in conventional alloantisera. It has further been shown that the anti-L chain antibody in all these sera was specific for L chain allotype determinants. Antibody against H chain-dependent L chain conformational determinants or cross-reacting determinants in CHlgamma and CHlalpha could not be demonstrated. |