[Proliferation of T lymphocyte subsets in asthma patients in clinical remission and molecular mechanism thereof].

OBJECTIVE: To explore the rule of proliferation of T lymphocyte subsets in patients with clinical asthma remission and the molecular mechanism. METHODS: Peripheral blood samples were collected from 15 asthmatic patients, 15 asthmatic patients in clinical remission, and 15 healthy control subjects, all sex-, and age-matched. CD(4)(+) T and CD(8)(+) T lymphocytes were isolated. Flow cytometry was used to examine the cell cycles of CD(4)(+) T and CD(8)(+) T lymphocytes. Fluorescence immunohistochemistry was used to detect the expression levels of cell cycle regulatory proteins (CCRPs), including cyclin D, cyclin E, and P27(kip1), PI3K, and STAT6. RESULTS: (1) The percentage of G(0)/G(1) phase of the CD(4)(+) T lymphocytes of the asthmatic patients was 82.00%, significantly lower than those of the asthmatic patients in clinical remission and healthy controls (92.50% and 99.00%, Z = 12.35, P < 0.01). The percentage of S phase of the CD(4)(+) T lymphocytes of the asthmatic patients was 18.00%, significantly higher than those of the asthmatic patients in clinical remission and healthy controls (6.10% and 0.20% respectively, Z = 8.05, P < 0.05). The percentage of G(2)/M phase of the CD(4)(+) T lymphocytes of the asthmatic patients was 2.80%, significantly higher than those of the asthmatic patients in clinical remission and healthy controls (0.40% and 0 respectively, Z = 9.16, P < 0.05). The S + G(2)/M phase of the CD(4)(+) T lymphocytes of the asthmatic patients was 18.00%, significantly higher than those of the asthmatic patients in clinical remission and healthy controls (7.50% and 0.20% respectively, Z = 12.80, P < 0.05). The distribution of G(0)/G(1) phase of CD(8)(+) T lymphocyte of the asthmatic patients was 44.60%, significantly lower than those of the asthmatic patients in clinical remission and healthy controls (95.90% and 100.00% respectively, Z = 21.60, P < 0.01). The distribution of S phase of CD(8)(+) T lymphocytes of the asthmatic patients was 51.70%, significantly lower than those of the asthmatic patients in clinical remission and healthy controls (0.80% and 0 respectively, Z = 25.22, P < 0.01). The distribution of S + G(2)/M phase of the CD(8)(+) T lymphocytes of the asthmatic patients was 55.40%, significantly higher than those of the asthmatic patients in clinical remission and healthy controls (4.10% and 0 respectively, Z = 21.52, P < 0.01). (2) The expression level of P27(kipl) of the CD(4)(+) T lymphocytes of the asthmatic patients was 13.20%, significant lower than those of the asthmatic patients in clinical remission and healthy controls (38.80% and 47.20% respectively, Z = 10.63, P < 0.01). The expression level of cyclin D of the CD(4)(+) T lymphocyte of the asthmatic patients was 35.00%, significant higher than those of the asthmatic patients in clinical remission and healthy controls (28.20% and 13.10% respectively, Z = 10.66, P < 0.01). The expression level of cyclin E of the CD(4)(+) T lymphocytes of the asthmatic patients was 7.90%, significant higher than those of the asthmatic patients in clinical remission and healthy controls (6.30% and 3.70% respectively, Z = 6.64%, P < 0.05). The expression level of P27(kipl) of the CD(8)(+) T lymphocyte of the asthmatic patients was 4.50%, significant lower than those of the asthmatic patients in clinical remission and healthy controls (33.80% and 46.30% respectively, Z = 9.30, P < 0.05). The expression level of cyclin D of the CD(8)(+) T lymphocyte of the asthmatic patients was 24.20%, not significant different from those of the asthmatic patients in clinical remission and healthy controls (26.10% and 32.20% respectively, Z = 0.09, P > 0.05). The expression level of cyclin E of the CD(8)(+) T lymphocyte of the asthmatic patients was 9.30%, significant higher than those of the asthmatic patients in clinical remission and healthy controls (5.60% and 3.50% respectively, Z = 4.91, P > 0.05). (3) The expression level of PI(3)K-110alpha of the CD(4)(+) T lymphocyte of the asthmatic patients was 7.60%, significant higher than those of the asthmatic patients in clinical remission and healthy controls (6.40% and 3.30% respectively, Z = 9.04, P < 0.05). The expression level of STST()6 of the CD(4)(+) T lymphocyte of the asthmatic patients was 8.20%, significant higher than those of the asthmatic patients in clinical remission and healthy controls (2.70% and 1.90% respectively, Z = 18.08, P > 0.01). The expression levels of PI(3)K-110alpha and STST(6) of the CD(8)(+) T lymphocytes of the asthmatic patients were not significant different from those of the asthmatic patients in clinical remission and healthy controls (Z = 4.91 and 5.70, both P > 0.05). CONCLUSION: There is excessive proliferation of CD(4)(+) T lymphocytes in the patients with clinical asthma remission, which may be related to the abnormal expression of CCRP (cyclin D, cyclin E, and P27(kip1)), PI(3)K, and STAT(6).