不同MBL基因型绵羊感染绵羊肺炎支原体后的免疫相关因子表达规律分析

Expression of the immune-associated factors in the sheep with different MBL genotypes after infected with Mycoplasma pneumoniae

将32只2月龄中国美利奴羊人工感染绵羊肺炎支原体(MP),分别在攻毒前1 d(-1 d)、攻毒后1 d、7 d、14 d和21 d收集新鲜抗凝血,提取总RNA后应用Real-time PCR的方法定量检测细胞因子IL-2、IL-4、IFN-γ、TNF-α,补体C1、C3和甘露糖结合凝集素(MBL)。结果表明,不同MBL基因型绵羊攻毒感染后血清MBL浓度呈下降趋势,其中MBL浓度较高的C型和D型绵羊,其促炎因子IL-2、IFN-γ浓度较高,抗炎因子IL-4在攻毒后1d呈升高趋势,此后开始下降;MBL浓度较低的A型和B型绵羊,攻毒后其TNF-α浓度升高显著,随炎症的舒缓,逐渐降低;补体C1和C3在攻毒后表现出不同的变化,证实MP感染后,激活补体途径,可能与MBL的浓度变化有关。

Thirty-two healthy Chinese Merino sheep were artificially infected with Mycoplasma pneumonia （MP）. The levels of IL-2, IL- 4, TNF-α, IFN-γ, C1, C3 and MBL in the serum were quantitatively assayed by ELISA on 1 day before infection （ -1d）, and on 1,7, 14 and 21 days of infection. The results showed that after artificial infection, MBL levels were decreased. With the duration of infection, the levels of the immune-associated factors changed differently. For the sheep with MBL types C and D of high MBL levels, the concentrations of proinflammatory cytokines IL-2 and IFN-7 were higher, while the concentration of IL-4 tended to increase on 1 day after infection and then began to decline. For the sheep with MBL types A and B of low MBL levels, the concentration of TNF-α increased significantly, and decreased with soothing inflammation. The complement C1 and C3 showed different changes after infection. The result showed that after MP infection, the activation of complement pathway may be related to the changes of MBL levels.