Objective: To investigate the expression of T cell early activation marker (CD(69)) on CD(4)(+) and CD(8)(+) lymphocytes in peripheral blood and the levels of soluble tumor necrosis factor receptor 1 (sTNF-R1) and sTNF-R2 in serum and bone marrow in patients with myelodysplastic syndrome (MDS).
Methods: Whole blood cell culture procedure was applied to activate T lymphocytes with phytohemagglutinin (PHA) (20 mg/L) in vitro. The expression rates of CD(69) on CD(4)(+) and CD(8)(+) lymphocytes at 0 h and 4 h after culture were analyzed with two-color flow cytometry. The levels of sTNF-R1 and sTNF-R2 in serum and bone marrow were measured with ELISA.
Results: There was an increase in the expression rates of CD(69) on CD(4)(+) and CD(8)(+) cells in RA and RAS patients (8.32% and 9.88% respectively) and in the expression rate of CD(69) on CD(8)(+) cells in RAEB and RAEB-T patients (7.92%) before PHA stimulation. CD(69) expression on CD(4)(+) and CD(8)(+) cells were significantly elevated in MDS patients after PHA stimulation (53.46% and 51.63% in RA + RAS; 42.93% and 41.96% in RAEB and RAEB-T) and the expression rate on CD(4)(+) cells was similar to that on CD(8)(+) cells. The levels of the two sTNF-R in MDS patients were elevated. sTNF-R1 in RA and RAS (1.58 +/- 0.68) micro g/L (PB), (2.10 +/- 0.26) micro g/L (BM); sTNF-R2 in RA and RAS (1.41 +/- 0.50) micro g/L (PB), (1.95 +/- 0.64) micro g/L (BM); sTNF-R1 in RAEB and RAEB-T (2.62 +/- 2.55) micro g/L (PB), (3.12 +/- 0.67) micro g/L (BM); sTNF-R2 in RAEB and RAEB-T (1.96 +/- 0.56) micro g/L (PB), (3.09 +/- 0.62) micro g/L (BM). The levels of sTNF-R2 in serum positively correlated to the expression rate of CD(69) on CD(8)(+) cells before PHA stimulation.
Conclusion: It is indicate that the increased early activation and activated potentials of T lymphocytes, along with abnormally elevated immunologically active molecules play an important role in immune pathogenesis of patients with MDS.