M. Kubo et al., Prevalence and antigen specificity of anti-histone antibodies in patients with polymyositis/dermatomyositis, J INVES DER, 112(5), 1999, pp. 711-715
Anti-histone antibodies have been detected in the sera of patients with var
ious autoimmune diseases. The existence of anti-histone antibodies in patie
nts with polymyositis/dermatomyositis, however, has not been reported. We f
ound anti-histone antibodies in eight (17%) of 46 sera from patients with p
olymyositis/ dermatomyositis by an enzyme-linked immunosorbent assay. One s
erum was positive for both IgG anti-histone antibodies and IgM anti-histone
antibodies. Six sera were positive only for IgG anti-histone antibodies, O
ne serum was positive only for IgM anti-histone antibodies. An indirect imm
unofluorescence analysis using HEp-2 cells as the substrate showed that all
sera positive for anti-histone antibodies produced homogeneous nuclear flu
orescence. This immunofluorescence pattern disappeared after absorption of
anti-histone activity with total histones. An immunoblotting analysis demon
strated that the anti-histone antibodies were predominantly directed agains
t histone H1 in all seven sera with IgG anti-histone antibodies. Weak react
ivity with H2B and H4 were also found in three sera from the patients with
polymyositis/dermatomyositis. Sera from two patients with polymyositis/derm
atomyositis displayed anti-H2A and H3 activity. One of the two sera showed
IgM anti-histone antibodies in the enzyme-linked immunosorbent assay reacte
d with H1, H2A, H2B, H3, and H4, whereas the other serum reacted with no fr
actions of total histones. The activity of anti-histone antibodies disappea
red in immunoblotting after absorption with total histones. All of the pati
ents with anti-histone antibodies were free from lung fibrosis or internal
malignancies. Thus, our data indicate that the presence of anti-histone ant
ibodies is classified as one of the serologic abnormalities observed in pol
ymyositis/ dermatomyositis.