哮喘患者外周血T淋巴细胞对VIP反应性的研究

目的:比较哮喘患者和正常对照者外周血T淋巴细胞对血管活性肠肽(VIP)的反应性差异。方法:分离缓解期哮喘患者和正常对照者外周血T淋巴细胞,以[³H]-TdR掺入率测定T淋巴细胞的增殖反应,以放射免疫法测定细胞内cAMP浓度(i),探讨VIP对ConA刺激细胞增殖反应的影响及其对i的调节作用在两种不同来源T淋巴细胞间的异同;此外还观察了Forskolin和NaF对上述来源细胞i影响差异。结果:两种来源T淋巴细胞对ConA的增殖反应相似(P＞0.05),然而,VIP对正常对照者T淋巴细胞的这种增殖反应的抑制效应却明显大于哮喘者T淋巴细胞(P＜0.01);这两种来源T淋巴细胞在静息时i基本相近,但VIP和NaF分别作用后对照组T淋巴细胞i增加幅度显著大于哮喘者T淋巴细胞;Forskolin作用后上述两种细胞i增加幅度相似(P＞0.05)。结论:在哮喘者VIP抑制ConA所致T淋巴细胞增殖能力减弱,可能与Gsα功能低下致其受体功能不全有关。

Responsiveness of the T-lymphocyte in peripheral blood from asthmatic patients to VIP

AIM: To investigate the functional state of vasoactive intestinal peptide (VIP) receptor on T-lymphocyte (T-cell)from asthmatics. METHODS: T-cells were purified from peripheral blood of asthmatics in remission and control subjects. Proliferation of T-cells was measured by [³H][³H]-TdR incorporation rate. The cAMP level in T-cells was assayed with radioimmunoassay method. We observed the influence of VIP on Con A-induced proliferation of T-cells, and cAMP level in T-cells in asthmatic and control groups. RESULTS: There was no difference in Con A-induced proliferation of T-cells between the two groups (P＞0.05). VIP, however, could inhibit the Con A-induced proliferation of T-cells from control subjects more significantly than that from asthmatics (P＜0.01). There was no difference in cAMP level in the unstimulated T-cells between the two groups (P＞0.05). The cAMP level in T-cells, however, increased more significantly in the control group than that in the asthmatic group after the treatment of VIP or NaF (P＜0.01,respectively). Adenylcyclase stimulator (forskolin)-treatment had no effect on the cAMP level in T-cells from the two groups (P＞0.05). CONCLUSION: Inhibition effect of VIP on Con A-induced proliferation of T-cells was less in asthmatics than in control subjects, which may be related to insufficiency of Gs α coupled VIP receptor on T-lymphocytes in asthmatics.