Yuan Ai-Yun, He Hong-Fang, Lyu Fu-Yan, Liu Pei-Pei, Hu Jing-Fei, Chen Zong-Bo
Department of Neurological Rehabilitation, Qingdao Women and Children's Hospital, Qingdao University, Qingdao, Shandong 266034, China.
Zhongguo Dang Dai Er Ke Za Zhi. 2017 Jan;19(1):39-43. doi: 10.7499/j.issn.1008-8830.2017.01.005.
To investigate the association of gene polymorphisms of Toll-like receptor 3 (TLR3)-1377C/T and expression of TLR3 with the susceptibility to enterovirus 71 (EV71) encephalitis in children.
A total of 187 children with EV71 infection (59 children in the encephalitis group and 128 in the non-encephalitis group) and 232 children who underwent physical examination were enrolled in the case-control study. Polymerase chain reaction-restriction fragment length polymorphism was used to detect the TLR3-1377C/T gene polymorphisms. ELISA was used to measure the serum level of TLR3.
There were no significant differences in the genotype and allele frequencies of TLR3-1377C/T between the non-encephalitis group and the encephalitis group. Compared with the control group, the encephalitis group and the non-encephalitis group had significant increases in the serum level of TLR3 (P<0.05), and the non-encephalitis group had the highest level (P<0.05). The encephalitis group had a significantly higher EV71 viral load than the non-encephalitis group (P<0.01). The children aged <1 year or ≥1 year in the encephalitis group and the non-encephalitis group had significant increases in the serum level of TLR3 compared with their counterparts in the control group (P<0.05), and the children aged <1 year or ≥1 year in the non-encephalitis group had a significantly higher serum level of TLR3 than those in the encephalitis group (P<0.05). In the encephalitis group, the children aged ≥1 year had a significantly higher TLR3 concentration than those aged <1 year (P<0.05), and there were no significant differences in the TLR3 concentration between the children aged ≥1 year and <1 year in the non-encephalitis group and the control group. In the encephalitis group, the proportion of children aged <1 year was significantly higher than those aged ≥1 year (P<0.05).
The TLR3-1377C/T gene polymorphisms are not significantly associated with the development of EV71 encephalitis. Low expression of TLR3 might weaken the inhibitory effect on virus replication and promote the development of EV71 encephalitis. The deficiency in the expression of TLR3 in serum after EV71 infection might be an important factor for the development of encephalitis in infants.
探讨Toll样受体3（TLR3）-1377C/T基因多态性及TLR3表达与儿童肠道病毒71型（EV71）脑炎易感性的关系。
选取187例EV71感染儿童（脑炎组59例，非脑炎组128例）及232例体检儿童作为病例对照研究对象。采用聚合酶链反应-限制性片段长度多态性方法检测TLR3-1377C/T基因多态性。采用酶联免疫吸附测定法检测血清TLR3水平。
非脑炎组与脑炎组TLR3-1377C/T基因型及等位基因频率差异无统计学意义。与对照组比较，脑炎组和非脑炎组血清TLR3水平均显著升高（P<0.05），且非脑炎组血清TLR3水平最高（P<0.05）。脑炎组EV71病毒载量显著高于非脑炎组（P<0.01）。脑炎组和非脑炎组年龄<1岁及≥1岁儿童血清TLR3水平均较对照组同年龄段儿童显著升高（P<0.05），且非脑炎组年龄<1岁及≥1岁儿童血清TLR3水平均显著高于脑炎组（P<0.05）。脑炎组中≥1岁儿童TLR3浓度显著高于<1岁儿童（P<0.05），非脑炎组和对照组中≥1岁与<1岁儿童TLR3浓度差异无统计学意义。脑炎组中<1岁儿童比例显著高于≥1岁儿童（P<0.05）。
TLR3-1377C/T基因多态性与EV71脑炎的发生无显著相关性。TLR3低表达可能减弱对病毒复制的抑制作用，促进EV71脑炎的发生。EV71感染后血清中TLR3表达不足可能是婴幼儿发生脑炎的重要因素。
