新生儿血清B族链球菌表面蛋白SCPB抗体检测

Naturally occurring antibodies to streptococcal C5a peptidase from group B streptococcus ( SCPB) in neonates

目的通过检测新生儿血清中B族溶血性链球菌(group B streptococcus,GBS)表面蛋白C5a肽酶(streptococcal C5a peptidase from group B streptococcus,SCPB)抗体,观察新生儿血清中SCPB抗体滴度,证实孕妇血中该表面蛋白抗体存在,为B族链球菌感染的免疫预防提供临床依据。方法收集2007年2月-12月住院的107例新生儿血清,采用酶联免疫试验(ELISA)检测血清中GBS表面蛋白SCPB抗体。结果107例新生儿血清标本中有21例SCPB抗体阳性,阳性率为19.63%;其中早产儿(<37周)SCPB抗体阳性率为3.7%,足月儿(≥37周)阳性率为25%,两者差异有统计学意义(P<0.05)。结论新生儿血清中存在GBS表面蛋白SCPB抗体,表明育龄期妇女自然感染GBS后可产生该蛋白抗体并通过胎盘传递给新生儿。SCPB抗体在孕妇及新生儿GBS感染中作用有待进一步研究。

Objective To detect the antibodies of streptococcal C5a peptidase from group B streptococcus （ SCPB） in neonates,demonstrate the existence of SCPB antibody in pregnant women after natural group B streptococcus （GBS） infection,and provide clinical evidence for prevention of GBS infection.Methods Sera were collected from 107 neonates （80 term infants and 27 premature infant） between February 2007 and December 2007.The antibodies of SCPB were detected using ELISA method,and cultures of GBS were done simultaneously.Results 21 （19.6%） newborns were found to be SCPB antibody positive （including 20 term infants and 1 premature infant）,the difference of positive ratio between term and premature infant was significant （ 25% and 3.7% ,respectively） .Conclusions This study indicated that pregnant women could produce SCPB antibody by immune response,and transmitted it to the infants through the placenta.Further study is needed to clarify the effect of SCPB antibody in expectant mother and newborn with GBS infection.