Different circulating lymphocyte profiles in patients with different subtypes of juvenile idiopathic arthritis

C.H.P. Wouters¹, J.L. Ceuppens², E.A.M. Stevens

¹Unit of Paediatric Rheumatology, Department of Paediatrics; ²Division of Allergy and Immunology, Department of Internal Medicine, University Hospital Gasthuisberg, Leuven, Belgium.

ABSTRACT
Objective
To determine the immunophenotypic profiles of circulating lymphocytes in patients with different disease types of Juvenile Idiopathic Arthritis (JIA).

Methods
Peripheral blood lymphocyte subsets from 19 patients with oligoarticular JIA (o-JIA), 10 patients with polyarticular JIA (p-JIA), 12 patients with systemic JIA (s-JIA) and from 41 age-matched healthy controls were characterized by two color immunofluorescence flow cytometry analysis.

Results
Patients with o-JIA and p-JIA had increased numbers of HLA-DR+ T cells and T cells co-expressing CD57 and CD16/56, indicating T cell activation and terminal differentiation of CD8+ T cells respectively. By contrast, in patients with s-JIA there was no increase in the activation or differentiation markers on T cells, but a profound decrease in circulating NK cells. All patients had hypergammaglobulinemia consistent with B cell hyperactivity, but increased numbers of CD5+ B cells were found only in o-JIA and p-JIA. 

Conclusion
Distinct immunophenotypic lymphocyte profiles in patients with o-JIA and p-JIA compared to patients with s-JIA as demonstrated in this study, are consistent with a fundamental heterogeneity of the disease.

Key words
Juvenile idiopathic arthritis, lymphocytes, flow cytometry

Please address correspondence to: C. Wouters, MD, PhD, Department of Paediatrics, University Hospital Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium. E-mail: Carine.Wouters@ uz.kuleuven.ac.be

Clin Exp Rheumatol 2002; 20: 239-248.
© Copyright Clinical and Experimental Rheumatology 2002.