Objective: To investigate the expression of TET2 and DLK1 mRNA in bone marrow CD(3)(+) T cells of patients with myelodysplastic syndrome (MDS) and their clinical significance and to explore the potential mechanism of abnormal cell-mediated immunity.
Methods: CD(3)(+) T cells were sorted by magnetic activated cell-sorting system. The expressions of TET2 and DLK1 mRNA in bone marrow CD(3)(+) T cells from 26 MDS patients and 16 healthy controls were detected by fluorescence quantitative PCR.
Results: The expression of TET2 mRNA in CD(3)(+) T cells was down-regulated in the MDS patients by (0.16 ± 0.15) fold compared with the controls (P < 0.05). The expression of TET2 mRNA in CD(3)(+) T cells of MDS patients was positively correlated with serum complement C(3) (r = 0.404, P < 0.05). The expression of DLK1 mRNA in CD(3)(+) T cells was up-regulated in the MDS patients by (1.61 ± 0.88) folds compared with the controls (P < 0.05). Grouped by the chromosomes, the patients with chromosome abnormalities presented significantly higher DLK1 mRNA level than those with normal chromosomes [(1.45 ± 0.44) folds, P < 0.05]. The expression of DLK1 mRNA in CD(3)(+) T cells of MDS patients was positively correlated with the proportion of bone marrow blasts (r = 0.343, P < 0.05).
Conclusions: The mRNA expression of TET2 in CD(3)(+) T cells of MDS patients was decreased while the mRNA expression of DLK1 was increased, which might decline the immune surveillance function. The findings would be useful for exploring the mechanism of immune tolerance.