Antigen binding with chromatin of immunocompetent cells

Binding of [125I] IgG to chromatin of spleen cells was studied in vivo, in vitro and to isolated chromatin. In vivo, maximal saturation of chromatin occurred 1 day after immunization (1.3 X 10(12) molecules per spleen, 10(8) cells). At the same level the antigen bound to chromatin in vitro. Binding of [125I] IgG with isolated chromatin was dependent on antigen concentration.