Chudwin D S, Artrip S G, Korenblit A, Schiffman G, Rao S
Infect Immun. 1985 Oct;50(1):213-7. doi: 10.1128/iai.50.1.213-217.1985.
C-reactive protein (CRP), an acute-phase reactant which binds to phosphocholine (PC) in the pneumococcal cell wall, and anti-PC antibodies are protective against experimental pneumococcal bacteremia in mice. To determine the relative opsonic capacities of CRP and anti-PC compared with those of antibodies against pneumococcal capsular polysaccharides (anti-PCP), we correlated in vitro opsonic activity for serotype 7F Streptococcus pneumoniae with concentrations of CRP, anti-PC, and anti-type 7F PCP in human sera from 10 normal subjects and 38 patients with sickle cell (SS) disease, a high-risk group for pneumococcal infection. Opsonic activity, measured by a radiolabeled bacterial uptake assay, correlated with anti-PCP levels but not with CRP or anti-PC in both the normal subjects and patients with SS disease. Addition of CRP to normal sera did not increase opsonic activity for serotypes 4 and 7F S. pneumoniae, although it did so for serotype 27, a nonpathogenic strain unique for having PC in its capsule. CRP and anti-PC were not effective opsonins when they bound to the pneumococcal cell wall rather than the capsule. The protective effects of CRP or anti-PC against these serotypes may be produced by means other than complement-dependent opsonization.
C反应蛋白（CRP）是一种急性期反应物，可与肺炎球菌细胞壁中的磷酸胆碱（PC）结合，抗PC抗体对小鼠实验性肺炎球菌菌血症具有保护作用。为了确定与抗肺炎球菌荚膜多糖抗体（抗PCP）相比，CRP和抗PC的相对调理能力，我们将10名正常受试者和38名镰状细胞（SS）病患者（肺炎球菌感染的高危人群）血清中7F型肺炎链球菌的体外调理活性与CRP、抗PC和抗7F型PCP的浓度进行了关联分析。通过放射性标记细菌摄取试验测量的调理活性与正常受试者和SS病患者的抗PCP水平相关，但与CRP或抗PC无关。向正常血清中添加CRP并没有增加4型和7F型肺炎链球菌的调理活性，尽管对27型肺炎链球菌有增加作用，27型是一种在其荚膜中含有PC的非致病菌株。当CRP和抗PC与肺炎球菌细胞壁而非荚膜结合时，它们不是有效的调理素。CRP或抗PC对这些血清型的保护作用可能是通过补体依赖性调理作用以外的其他方式产生的。
