Antibodies to histones in rheumatoid arthritis.

Using a newly developed enzyme-linked immunosorbent assay, antibodies to histones (H1, H2A, H2B, H3 and H4) were found in 32 out of 40 rheumatoid arthritis patients with antinuclear antibodies at a titer greater than or equal to 100 as measured by indirect immunofluorescence. The anti-H2A reactivity was higher in patients with secondary Sjögren's syndrome than in those without, but the highest antihistone reactivity and the most heterogeneous patterns were observed in patients who were receiving D-penicillamine.