To determine the incidence of anti-hsp90 and 70 antibodies in children with SLE, juvenile dermatomyositis and juvenile chronic arthritis.
We utilized a previously described ELISA to detect the presence of antibodies to mammalian hsp90 and 70 in 33 children with SLE, 55 with juvenile chronic arthritis (JCA) and 11 with dermatomyositis. Sera from 19 children with non-autoimmune conditions served as controls.
Antibodies reactive with hsp90 and/or 70 were detected in 35% of the children with SLE, and the numbers of children with SLE who have raised IgG anti-hsp90 antibodies (24%) is very similar to our adult onset cases, although the prevalence of IgM antibodies is much smaller. However, serum antibodies to hsp70 were as infrequent in children with SLE or JCA as in adults with SLE or RA, although IgG antibodies to hsp70 were detected in 50% of the synovial fluid of JCA patients.
The incidence of antibodies to hsp90 in childhood-onset SLE resembles that described in adult onset disease suggesting that, despite clinical differences between the two, a subset of each may share a similar pathological mechanism of disease.