OBJECTIVE. Fibromyalgia (FM) is a clinical entity of unknown
etiology frequently diagnosed in rheumatology. The potential
involvement of the immune system in its pathogenesis has been
suggested. Studies of abnormal T cell subpopulations often
have been inconclusive. We attempted to clear this point by
comparing lymphocyte subpopulations, including some of the
newer activation markers, in patients with FM and healthy
METHODS. Sixty-five patients with FM and 56 healthy
controls were studied. Flow cytometry was used as a
quantification technique to measure lymphocyte subpopulations,
CD3 (T cells), CD19 (B cells), CD16 (natural killer cells),
CD4 (T helper/inducer cells), CD8 (T cytotoxic/suppressor
cell), CD25 (interleukin 2 receptor), CD69 (activation inducer
molecule marker), CD71 (transferrin receptor) and CD54
(ICAM-1); CD4/CD8 ratios were also estimated.
number of T cells expressing activation markers CD69 and CD25
was decreased in patients with FM; the other subpopulations
were similar in patients and controls.
CONCLUSION. Our results
suggest a defect in T cell activation in patients with FM.
Hernanz W, Valenzuela A, Quijada J, Garcia A, de la Iglesia JL,
Gutierrez A, Povedano J, Moreno I, Sanchez B