Nonhistone nuclear antigens reactive with autoantibodies. Immunofluorescent studies of distribution in synchronized cells

Abstract

Sera from patients with certain autoimmune diseases that contained autoantibodies to nonhistone nuclear antigens were used as reagents in an indirect immunofluorescent study. The distribution of these nuclear antigens was determined in synchronized human B lymphoid cells. Autoantibodies to Sm antigen, nuclear ribonucleoprotein complex and SS-B antigen were used. Although all three nonhistone antigens appeared to show speckled nuclear staining patterns in the G0 phase, different patterns of staining were present at other periods of the cell cycle. The SS-B antigen showed a distinctly nucleolar localization during the G1/early S phase. These studies demonstrate that autoantibodies occurring in certain human diseases can be useful reagents for the immunohistological localization of nuclear macromolecules and for tracing their pathways during phases of cell growth and differentiation.