肺炎支原体CARDS毒素对小鼠IgE反应的影响及机制

Effect of mycoplasma pneumoniae CARDS toxin on Ig E response in mice

目的通过肺炎支原体产生的特异性CARDS毒素对血清总IgE的作用,研究其对机体过敏反应的影响。方法 60只SPF级BALB/c小鼠分为对照组和感染组,采用CARDS毒素暴露小鼠模型,评价CARDS毒素特异性反应;肥大细胞脱颗粒研究确定CARDS毒素特异性IgE的功能;Western blot检测JAK3及STAT6的表达;给予热灭活毒素以及STAT6抑制剂检测二者对血清IgE的影响。结果单次暴露于CARDS毒素即可增加小鼠血清总IgE,并持续较长时间;给予CARDS毒素二次暴露的小鼠总IgE仍显著升高,诱导肥大细胞脱颗粒,诱导JAK3和STAT6表达增加,血清IgE的升高需要CARDS毒素的酶活性和STAT6共同作用。结论肺炎支原体CARDS毒素特异性IgE在小鼠体内的存在导致IgE依赖性介质的释放,导致肥大细胞脱颗粒,与哮喘发病及恶化密切相关。

Objective To study the effect of Mycoplasma pneumoniae CARDS toxin on serum total IgE and its allergic reaction to the body. Methods 60 SPF BALB/c mice were divided into control group and infection group. The specific reaction of CARDS toxin was evaluated by the model of mice exposed to CARDS toxin, and the function of specific IgE of CARDS toxin was determined by mast cell degranulation. The expression of JAK3 and STAT6 was detected by Western blot. HI-CARDS and AS1517499 were used to evaluate the influence factor of IgE in serum. Results The total IgE in serum was increased by a single exposure to CARDS toxin, last for a long time. The total IgE of mice exposed to the second time of CARDS toxin was still increased significantly. CARDS toxin induced degranulation of mast cells, increased the expression levels of JAK3 and STAT6. The increase of serum IgE requires the interaction of the enzyme activity of CARDS toxin and STAT6. Conclusion Mycoplasma pneumoniae CARDS toxin specific IgE is closely related to the pathogenesis and deterioration of asthma.