RESUMO
The aim of the study was to analyze the naive T cell level of thymic recent output in patients with B-cell malignancies, thereby to evaluate the potential T-cell function. Quantitative analysis of T-cell receptor rearrangement excision circles (TRECs) in DNA of peripheral blood mononuclear cells from 61 cases of B-cell lymphocytic malignancy (including 20 cases of adult B-ALL, 6 case of childhood B-ALL, 4 cases of B-CLL, 17 cases of B-NHL and 14 cases of MM) were preformed by real-time PCR (TaqMan), and TREC-level was detected according to the number of CD3-positive cells. 5 case of ALL-CR and 17 normal individuals were served as controls. The results showed a dramatic reduction of TREC values in all groups of patients. The mean value of TRECs was 0.53 +/- 1.52 copies/1000 PBMNC and 2.01 +/- 3.93 copies/1000 CD3+ cells in adult B-ALL (p = 0.0005, p = 0.0123), 0.11 +/- 0.15 copies/1000 PBMNC and 0.23 +/- 0.27 copies/1000 CD3+ cells in B-CLL (p = 0.0015, p = 0.0381), 0.71 +/- 1.34 copies/1000 PBMNC in B-NHL (p = 0.0017), 0.53 +/- 0.90 copies/1000 PBMNC in MM patients (p = 0.0018), as compared with 3.76 +/- 3.42 copies/1000 PBMNC and 5.87 +/- 4.96 copies/1000 CD3+ cells in normal individuals, the TREC level was significantly decreased in all groups of B-cell lymphocytic malignancy, as well as in ALL-CR group. However, the TREC level in childhood B-ALL was significant higher than those in adult B-ALL group. It is concluded that the function of thymic recent outputting naive T cells in B-cell malignancies significantly decreases, however, the individual difference of thymic output function is obvious. The thymic recent output function can not be recovered during CR phase in patients with B-cell malignancies, so that dynamic analysis of TREC level is necessary.