Study On Th1/Th2 Balance In Bronchoalveolar Lavage Fluid Of Mycoplasma Pneumoniae Pneumonia In Children

Objective:According to the researching for the level of cytokines in the bronchoalveolar lavage fluid(BALF)of children with the bronchial foreign body,and to investigate the changes of Th1/Th2 immune balance,further evaluate the effect of cytokine imbalance on MPP disease,providing new detection technologies for the pathogenesis of MPP,and further to guide the clinical diagnosis,treatment and prognosis to provide theoretical basis and optimization approach.Methods:Firstly,31 cases children needed fiberoptic bronchoscopy after hospitalized were divided into three groups(bronchial foreign bodies,mild MPP and severe MPP)meeting to the inclusion criteria,we extracted bronchoalveolar lavage fluid(bronchoalveolar lavage fluid,BALF)samples and obtained the cytokine's RNA through technological means;Then we obtained the level of cytokines IFN-? and IL-4 using the Real-time PCR,calculated the IL-4/IFN-? and summed up its change trend;Secondly,9 cases chosen from total cases were divided into the same groups above-mentioned,we verified the level of cytokine of IFN-? and IL-4 from BLAF samples using next-generation sequencing NGS(transcription group)and IL-4/IFN-? was calculated and at last analyzed statistically.Results:1.Real-time PCR test results showed that the expression level of IL-4 and IFN-? in BALF form both mild and sever group was significantly higher than that in the control group(P < 0.05).The difference between MPP mild group and severe group was not statistically significant(P >0.05).2.Real-time PCR test results showed that there was a significant difference in the ratio of IL-4/IFN-? in BALF between MPP group and control group(P < 0.05),but there was no significant difference between MPP severe group and foreign body control group,and between MPP mild group and severe group(P >0.05).3.NGS showed that the levels of IL-4 and IFN-? in BALF from sever group were higher than mild MPP group's and the levels' from mild MPP group were higher than bronchial foreign bodies group's.The IL-4/IFN-? of mild MPP group and severe MPP group were all higher than bronchial foreign bodies group's.However,serve group's IL-4/IFN-? less than mild MPP group's.Conclusion:1.By the next generation sequencing and Real-time PCR detected in children with MPP immune reaction,two kinds of Th1 and Th2 cytokines' levels were increased in BALF form mild and severe MPP,and indicates that cellular immunity imbalance exists in MPP.2.Real-time PCR showed that the mild group showed Th2 reaction is predominant compared to control group with foreign body;according to the results of NGS sequencing of the IL-4/IFN-?,we can speculate that Th2 reaction was more obvious.