The Expression and Significance of CD4+T Lymphocyte in the Peripheral Blood of Patients with Asthma

Objective: To detect the CD4 +T lymphocyte proportion in the peripheral blood of the patients with bronchial asthma at different stages by flow cytometry. Methods: 53 patients with asthma were recruited and divided into three groups: the acute exacerbation group of 28 cases, the mild remission group of 20 cases and the moderate to severe remission group of 5 cases. At the same time, the normal controlled group of 16 cases was set up as contrast. The proportion of Th1, Th2, Th17 and Treg in the peripheral blood of the patients with asthma and normal controlled cases were detected by flow cytometry respectively. Lung function tests were simultaneously performed in the patients with asthma groups and normal controlled group. High-resolution CT was taken in the remission and the normal group, then the ratio of 2 airway wall thickness to outer diameter (2T/D), the ratio of wall area to total airway area (WA%), lung densities in both the inspiratory and expiratory phases and the two phase difference were measured in everyone who took the HRCT. Results: The acute group had a much lower Th1 and Treg proportion than the mild remission group and the normal group (P<0.05), and the remission group also had a lower proportion than the normal controlled group (P<0.05), but the Th1 and Treg proportion difference was not statistically significant between the two remission groups; The proportion of Th2 and Th17 in peripheral blood in acute group was higher than that in the mild remission group and the normal group (P<0.05), and that in the two remission group was also higher than that in the normal group (P<0.05), the proportion of Th2 in the acute group was higher than that in the moderate-severe remission group, but Th17 was not statistically significant between the two groups, the proportion of Th17 in the moderatesevere remission group was higher than that in the mild remission group, but Th2 was not different between the two groups; The ratio of Th1, Th2 and the ratio of Th17, Treg was obviously significant between the acute group, the mild remission group and the normal group (P<0.01), the ratio of Th17 and Treg between any two groups was statistically significant (all P<0.05), whereas the ratio of Th1 and Th2 was not significant between the mild remission group and the moderate to severe remission group, but it was also significant among the other two groups; 2T/D, WA%, expiratory phase CT values and the different CT values between inspiratory phase and expiratory phase were statistically significant among the two remission and the normal groups (P<0.05), but inspiratory phase CT value in the three groups showed no significant difference. Conclusions: There were CD4 + T lymphocyte immunological function disorders in peripheral blood of patients with acute exacerbation and remission of asthma, of which Th2 and Th17 had an enhanced immune response phenomenon, with an obviously enhanced expression for Th17 cells in moderate-severe remission asthma patients, However, Th1 and Treg cells with a protective effect had a lower functioning. Therefore there existed not only Th1/ Th2 imbalance but also Th17/Treg imbalance in peripheral blood of asthma; airway wall thickness pathological changing phenomenon and gas retention phenomenon existed in asthmatic patients too; the diffusion capacity of patients with bronchial asthma and the normal controlled group did not be obviously different.