Immunofluorescent study of chromatin proteins in cultured fibroblasts

Antibodies against chromatin from 3T6 mouse fibroblasts and WI-38 human diploid fibroblasts were prepared by immunization of rabbits. Immunofluorescent studies showed species-specificity of these antichromatin antibodies. Furthermore, using anti-3T6 chromatin antibodies against 3T6 cells and anti-WI-38 chromatin antibodies against WI-38 cells, we observed, by immuno-fluorescent techniques, granular fluorescence in the diffusely stained nucleus and diffuse fluorescence in the cytoplasm. These results raise the possibility of the presence of a cytoplasmic pool of chromatin proteins.