LACK OF TEMPORAL ASSOCIATION OF IRIDOCYCLITIS WITH IGG REACTIVITIES TO CORE HISTONES AND NUCLEOSOME SUBPARTICLES IN PAUCIARTICULAR JUVENILECHRONIC ARTHRITIS

This study aimed to measure IgG reactivities to DNA-free nucleosome su bparticles (H2AH2B, H3H4) and nucleosome subparticles (H2AH2B-DNA, H3H 4-DNA) and to evaluate the temporal relation of these reactivities, as well as those to single core histones: with iridocyclitis (IC) in pat ients with antinuclear antibody positive (ANA+) pauciarticular juvenil e chronic arthritis (JCA). Reactivities to nuclear substrates were det ermined by enzymatic immunoassays in 120 sera from 45 children with AN A+ pauciarticular JCA. Significantly elevated IgG levels to H3 and H4, to DNA-free nucleosome subparticles. and to the nucleosome subparticl e K3H4-DNA were present in patients with ANA+ pauciarticular JCA; no e vidence of recognition of conformational epitopes was found. In both h orizontal and follow-up studies, no relation between the reactivities studied and the development, presence, or history of IC was found. Our results show the absence of a relation of antibodies to histone molec ules or to nucleosome subparticles with IC in patients with ANA+ pauci articular JCA.