Objective To observe the changes of NK cell subset (CD56+,CD16+CD56+,CD16+),T cell subset (CD4+,CD8+,CD4+/CD8+) counts and related cytokines (IL-2,IL-4,INF-γ) in children with viral pneumonia.Methods Thirty-two children with viral pneumonia in acute stage (within 2 days after pneumonia onset) and recovery phase (within the range of the third to the fifth day after pneumonia onset) were included in this study.Peripheral blood NK cell subsets and T cell substes were determined by the flow cytometry.Blood IL-2,IL-4 and INF-γ were detected by ELISA.NK cytoactivity was measured by LDH release method.Results (1) The levels of the CD16+CD56+ and CD16+NK cell counting in acute stage [(0.73±0.17)% and (0.39±0.20)%] were lower than those in the recovery phase [(1.47±0.22)% and (0.89±0.14)%],which showed significant difference (P<0.01),however the level of CD16+CD56+ and CD16+NK cell counting either in acute stage or recovery phase was significantly lower than those of healthy control group (P<0.01).The sub population counting and NK cell activity was directly correlated.CD56+NK cell counting showed no significant difference between viral pneumonia group and control group (P>0.05).(2) There was no significant difference in blood IL-2 and IL-4 level between viral pneumonia group (either in acute stage or recovery phase) and the control group (P>0.05).As compared with that of the control group,blood INF-γ level of viral pneumonia group showed no significant change in acute stage (P>0.05),but INF-γ level in recovery phase [(28.10±1.38)?μg/L] was higher than that in acute stage [(22.78±1.19)?μg/L] and there was significant difference (P<0.01).(3) As compared with that of the control group,CD4+ and CD4+/CD8+T cell counting of viral pneumonia group showed no obvious changes either in acute stage or recovery phase (P>0.05).CD8+T cell counting of both two stages were much lower than that of the control group (P<0.05),but there was no significant difference between the two stages (P>0.05).Conclusion The NK cell activity in children with viral pneumonia decline obviously,which might be related to the changes of T cell subsets;the activity of suppressor T cell was depressed in patients with viral pneumonia.There are maybe many factors involved in the NK cell activation.

Objective To study the influence of gamma globulin to serum B cell activating factor (BAFF) in therapy of neonatal thrombocytopenic purpura.Methods Fifteen cases with neonatal thrombocytopenic purpura(treatment group) were treated with gamma globulin.Serum BAFF levels of treatment group before and after treatment and 20 healthy neonates(control group) were tested.Results Serum BAFF level of the treatment group before treatment was(0.96±0.48) μg/L,which was statistically significant compared with that of the control group[(0.48 ±0.35) μg/L](P ＜0.05).Serum BAFF level of treatment group after treatment was (0.45 ± 0.37) μg/L,which was statistically significant compared with that of before treatment (P ＜ 0.05),but was not statistically significant compared with that of the control group.Conclusion Gamma globulin can play a role in the therapy of neonatal thrombocytopenic purpura by reducing the BAFF.