Humoral immunity in juvenile rheumatoid arthritis

Abstract

Compared with matched healthy individuals, patients with juvenile rheumatoid arthritis (JRA) were found to have a normal primary humoral response to Brucella antigens and an increased secondary humoral response to immunization of diphtheria and tetanus antigens. Significantly increased serum levels of IgG, IgA, and IgM were found in the patient group, whereas the level of naturally occurring antibodies (iso hemagglutinins and antibodies to rabbit erythrocytes) were normal. No adverse clinical effect was observed after the immunizations. Serologically, both groups had a significant increase in the pepsin agglutinator titre. Although the results were not consistent, it may thus appear that patients with JRA have a higher activity in the humoral part of the immunological apparatus than controls. Further studies are needed to verify and evaluate the significance of the dissociation of the primary and secondary antibody responses, and the possible inverse correlation between the increased secondary humoral response and the impaired delayed hypersensitivity reactivity observed in these patients.