McQuillen D P, Gulati S, Ram S, Turner A K, Jani D B, Heeren T C, Rice P A
Maxwell Finland Laboratory for Infectious Diseases, Boston Medical Center, 774 Albany Street, Boston, Massachusetts, USA.
J Infect Dis. 1999 Jan;179(1):124-35. doi: 10.1086/314545.
Local inflammation elicited by Neisseria gonorrhoeae correlates closely with sensitivity to killing by normal human serum. Serum-sensitive (SS) isolates are rendered resistant in vitro by lipooligosaccharide sialylation. Differences in C3b processing on N. gonorrhoeae in vitro were found to match findings at the cervical level in vivo. Nonsialylated SS gonococci bound 5-fold more C3b than did stably serum-resistant (SR) gonococci; most was processed to iC3b, yet significant C3b persisted. Sialylated SS gonococci bound 4-fold less total C3 antigen than did SR gonococci, which was promptly converted to iC3b. C3b bound later on stably SR gonococci but again was processed swiftly to iC3b. In vivo, the iC3b/C3 ratio of SS isolates more closely resembled nonsialylated SS isolates in vitro, implying heterogeneous sialylation or desialylation in vivo. In vitro, total IgM bound was unchanged by sialylation of SS isolates, but total C4 bound decreased by 75%, suggesting that sialylation may indirectly regulate the classical complement pathway.
淋病奈瑟菌引发的局部炎症与对正常人血清杀伤的敏感性密切相关。血清敏感（SS）菌株通过脂寡糖唾液酸化在体外获得抗性。体外研究发现，淋病奈瑟菌上C3b处理的差异与体内宫颈水平的研究结果相符。未唾液酸化的SS淋球菌结合的C3b比稳定血清抗性（SR）淋球菌多5倍；大部分C3b被加工成iC3b，但仍有大量C3b留存。唾液酸化的SS淋球菌结合的总C3抗原比SR淋球菌少4倍，且能迅速转化为iC3b。稳定的SR淋球菌上C3b结合较晚，但同样迅速被加工成iC3b。在体内，SS菌株的iC3b/C3比值更类似于体外未唾液酸化的SS菌株，这意味着体内存在唾液酸化或去唾液酸化的异质性。在体外，SS菌株的唾液酸化对总IgM结合无影响，但总C4结合减少了75%，这表明唾液酸化可能间接调节经典补体途径。
