A model implicating altered macrophage function in H-2 linked nonresponsiveness to hen lysozyme.

Studies on the basis of differential responsiveness of H-2b mice to gallinaceous lysozymes suggest T cell involvement and active T cell suppression with those lysozymes not responded to. Results from other laboratories suggesting a directive role for macrophages through limited presentation are summarized. A model is presented proposing that suppressors (recognizing a determinant only on lysozymes not responded to) are present in all strains; that suppression requires antigen bridging between suppressor determinant and positive T determinant; that this bridge is disrupted in all strains but H-2b; and that this failure to disrupt the antigen bridge is a result of a genetically (Ia) controlled loss of a normal macrophage processing step.