Changes Of Toll Like Receptor-2 Signal Pathways And Related Inflammatory Factors In Serum Of Children With Refractory Mycoplasma Pneumoniae Pneumonia

Objective By analyzing the changes of mRNA and protein of Toll-like receptor 2(TLR2),myeloid differentiation primary response 88(MyD88),nuclear factor-?B(NF-?B)and related inflammation factors,to explore the pathogenesis of refractory mycoplasma pneumoniae pneumonia(RMPP),in order to facilitate early identification and early intervention.Methods Results The case was selected from October 2017 to October 2018 at the Chifeng Clinical Medical College of Inner Mongolia Medical University.The healthy control group,the RMPP group and the Mycoplasma pneumoniae pneumonia(MPP)group were established according to the inclusion and exclusion criteria.All selected cases recorded clinical data in detail,2 ml of venous blood was taken at the time of consultation or after hospitalization,and centrifuged at 3000 rmp/min for 10 min at 4 °C.The obtained serum and cellular components were dispensed into sterile EP tubes.The levels of human interferon-gamma(IFN-?),human interleukin-8(IL-8),human cysteinyl leukotriene(CysLTs)and human monocyte chemoattractant protein 4(MCP-4)were detected by enzyme linked immunosorbent assay(ELISA).The mRNA and protein expressions of TLR2,MyD88 and NF-?B in blood were detected by reverse transcription-polymerase chain reaction(RT-PCR)and Western blot.The obtained data was subjected to statistical analysis.Results 1.The number of disease days and fever days in the RMPP group were higher than those in the MPP group,and the difference was statistically significant(P<0.05).2.White blood cell(WBC),percentage of neutrophils(N%),C-reactive protein(CRP)and lactate dehydrogenase(LDH)in the RMPP group and the MPP group were significantly higher than those in the healthy control group,and the difference was statistically significant(P<0.05);WBC,N%,CRP and LDH were significantly higher in the RMPP group than in the MPP group,and the difference was statistically significant(P<0.05).3.The levels of IFN-?,CysLTs,IL-8 and MCP-4 in the normal MPP group and RMPP group were significantly higher than those in the healthy control group,and the difference was statistically significant(P<0.05);Compared with the normal MPP group,the RMPP group showed significantly higher IFN-?,CysLTs and IL-8 levels,and the difference was statistically significant(P<0.05).There was no difference in MCP-4(P>0.05).4.The mRNA expression levels of TLR2,MyD88 and NF-?B in the RMPP group were significantly higher than those in the MPP group and the control group(P<0.05).The mRNA expression level of TLR2 in MPP group was higher than that in the control group,the difference was statistically significant(P<0.05),and there was no difference in MyD88 and NF-?B expression(P>0.05).5.The protein expression levels of TLR2,MyD88 and NF-?B in the RMPP group and the normal MPP group were significantly higher than those in the control group(P<0.05).Compared with the normal MPP group,the expression of TLR2,MyD88 and NF-?B protein was significantly increased in the RMPP group,and the difference was statistically significant(P<0.05).Conclusion 1.The WBC,N%,CRP,LDH,duration of disease and fever time of children with MPP may be RMPP when they are significantly increased.2.The levels of IFN-?,CysLTs and IL-8 in the blood of RMPP group were significantly increased,suggesting that immune dysfunction is one of the causes of RMPP.3.Abnormal activation of TLR2/MyD88/NF-?B pathway in children with RMPP may be associated with increased expression of inflammatory factors.