Objective: To determine expressions of Fas and Bcl-2 on peripheral blood T and B lymphocytes from patients with juvenile-onset systemic lupus erythematosus (JSLE).
Methods: Thirty-eight patients with JSLE and 21 healthy controls were studied. Eleven JSLE patients with SLEDAI score >or= 8 were categorized as active. Freshly isolated peripheral blood mononuclear cells were stained for lymphocyte markers CD3, CD4, CD8, and CD19 and for Fas and Bcl-2 molecules. Cell protein expression was measured by 3-color flow cytometry.
Results: Percentages of lymphocytes positively stained for Fas antigen and cytoplasmic expression of Bcl-2 measured by mean fluorescence intensity from patients were significantly increased compared to controls on CD3+, CD4+, and CD8+ T cells. Patients with active disease had higher percentages of CD19+ B cells positive for Fas antigen compared to patients with inactive lupus. A direct statistical correlation was observed between Fas and Bcl-2 expression on CD19+ B cells and SLE Disease Activity Index score.
Conclusion: Patients with juvenile-onset SLE show upregulation of apoptosis-related proteins. Patients with active and inactive disease have a different profile of Fas and Bcl-2 expression.