Expression of CD40-CD40L on peripheral blood lymphocytes of patients with Ankylosing spondylitis

Objective To investigate the relationship between abnormal expression of costimulator molecule CD40-CD40L on lymphocyte subpopulation and the immune dysfunction in patients with ankylosing spondylitis (AS). Methods Samples from 30 AS patients and 20 healthy controls were analyzed by immunofluorescence and flow cytometry, for determining the expressions of CD3, CD4, CD8, and CD19 on lymphocytes,CD40L on CD4+ T cells or CD8+ T cells,and CD40 on CD19+ B cells. IgG, IgA, and IgM in serum were determined by rate nephelometry. Results As compared with controls, the CD3+ T cells, CD3+CD4+ T cells, and CD19+ B cells in AS patients were significantly increased (P 0.05), but the CD3+CD8+ cells were significantly decreased (P 0.05). The CD40L expressed on CD4+ T cells and CD8+ T cells, and the CD40 expressed on CD19+ B cells in AS patients, were all significant higher than those in healthy controls (P 0.05). The levels of IgG and IgA in serum of AS patients were significant higher than those in healthy controls (P 0.05). Conclusion CD40-CD40L pathway may play an important role in immune dysfunction of AS patients.