Center for Chronic Immunodeficiency, University Medical Center Freiburg and University of Freiburg, Freiburg, Germany.
J Infect Dis. 2012 Apr 1;205(7):1076-85. doi: 10.1093/infdis/jis022. Epub 2012 Feb 23.
Type 1 lipoteichoic acid (LTA) is present in many clinically important gram-positive bacteria, including enterococci, streptococci, and staphylococci, and antibodies against LTA have been shown to opsonize nonencapsulated Enterococcus faecalis strains. In the present study, we show that antibodies against E. faecalis LTA also bind to type 1 LTA from other gram-positive species and opsonized Staphylocccus epidermidis and Staphylcoccus aureus strains as well as group B streptococci. Inhibition studies using teichoic acid oligomers indicated that cross-reactive opsonic antibodies bind to the teichoic acid backbone. Passive immunization with rabbit antibodies against E. faecalis LTA promoted the clearance of bacteremia by E. faecalis and S. epidermidis in mice. Furthermore, passive protection also reduced mortality in a murine S. aureus peritonitis model. The effectiveness of rabbit antibody against LTA suggests that this conserved bacterial structure could function as a single vaccine antigen that targets multiple gram-positive pathogens.
1 型脂磷壁酸（LTA）存在于许多临床重要的革兰氏阳性菌中，包括肠球菌、链球菌和葡萄球菌，并且已经证明针对 LTA 的抗体可以调理非荚膜粪肠球菌菌株。在本研究中，我们表明针对粪肠球菌 LTA 的抗体也与其他革兰氏阳性菌的 1 型 LTA 结合，并调理表皮葡萄球菌和金黄色葡萄球菌以及 B 组链球菌。使用磷壁酸低聚物的抑制研究表明，交叉反应性调理抗体结合到磷壁酸主链上。用针对粪肠球菌 LTA 的兔抗体进行被动免疫可促进粪肠球菌和表皮葡萄球菌菌血症在小鼠中的清除。此外，被动保护还降低了小鼠金黄色葡萄球菌腹膜炎模型的死亡率。针对 LTA 的兔抗体的有效性表明，这种保守的细菌结构可以作为一种单一的疫苗抗原，针对多种革兰氏阳性病原体。
