Methods: 85 asthmatic children who were diagnosed and treated by pediatric department of Renmin Hospital Affiliated to Wuhan University from Jan. 2012 to Dec. 2014 were selected as asthmatic group. 76 healthy children were selected as control group. The peripheral blood mononuclear cells were collected by using the density gradient centrifugation method. The ratio of peripheral blood NKT cells and CD4+ NKT cells were measured by immunofluorescence and flow cytometry assays. The relationships between the NKT cells number, CD4+ NKT cells and the total IgE level were observed. The levels of IL-4,IL-13, IFN-γ in peripheral blood were detected by enzyme-linked immunosorbent assay after proliferate in response to α-Galcer.
Results: Compared with the control group, the ratio of NKT cells and CD4+ NKT cells in peripheral blood in asthmatic group were significantly decreased (t=3.795,P<0.05; t=4.106,P<0.05). There was no significant correlation between the NKT cells,CD4+ NKT cells and the total IgE（t=1.032,P>0.05; t=0.856,P>0.05）. The levels of IL-4 and IL-13 in asthmatic group were higher than that of the control group（t=4.683,P<0.05; t=3.992,P<0.05）. There was no significant difference in the level of IFN-γbetween the two groups（t=0.877,P>0.05）.
Conclusion: The dysfunction of NKT cells and CD4+ NKT cells and the functional change of cytokines may play an important role in the pathogenesis of asthma.