鼻病毒A21型人群血清中和抗体分布特点

Characteristics of distributions of serum neutralizing antibodies to human rhinovirus genotype A21

目的既往研究发现鼻病毒（human rhnivirus，HRV）21型可导致人重症感染和死亡，其抗原位点发生变异，为深入揭示其病原学意义，本研究分析了HRVA21在人群的血清中和抗体分布特点。方法用人宫颈癌细胞H1-HeLa从临床样本中分离HRVA21毒株。病毒经纯化后进行基因组序列的鉴定和滴度测定。用固定病毒稀释血清方法测定不同年龄组健康人群血清中和抗体水平。结果获得了HRVA21病毒毒株，其基因组序列与来源的样本中序列同源性100%。在379份血清中，以0～5岁、5～14岁、15～25岁、26～45岁、46～60岁和60岁以上分为6组，HRVA21中和抗体阳性率分别为21.7%、14.1%、28.2%、25.4%、27.9%和20.7%。仅〉5～14岁和15～25岁组间HRVA21中和抗体阳性率差异有统计学意义（χ^2＝4.68454, P＝0.03044），两组中和抗体滴度几何均数也差异有统计学意义（P＝0.0313）。结论HRV-A21在不同年龄组人群中血清中和水平均较低，提示其低水平流行及人群高易感性。

ObjectiveHuman rhinovirus A21 （HRVA21） with mutations in antigenic gene has been reported causing severe human infections. This study aimed to investigate intensively the pathogenesis of HRVA21 by identifying the characteristics of neutralizing antibodies （NAbs） distribution.MethodsVirus stock was isolated from HRVA21-positive respiratory specimens. The tissue culture infective dose 50 （TCID50） was applied. Sera from healthy volunteers in different age groups were used to analyze the NAbs by using the diluted serum and fixed viral TCID50.ResultsWe obtained the HRVA21 virus stock and its whole genome sequences shared 100% similarity to the used clinical sample. In the 379 collected serum samples, the positive rates of NAbs were 21.7%, 14.1%, 28.2%, 25.4%, 27.9% and 20.7% in age groups of 0-5 y, 5-14 y, 15-25 y, 26-45 y, 46-60 y and 〉 60 y, respectively. In age groups of 〉5-14 y and 15-25 y, the positive rate of NAbs showed significantly different （χ^2=4.68454, P=0.03044）. Higher geometric mean titers were found in 15-25 y group compared to 5-14 y age groups （P=0.0313）.ConclusionsThe low level of HRVA21 NAbs in different age groups indicated a low epidemic of HRV21 infection and high susceptability to infections by the virus.