PDF(Pubmed)
Abstract：
To address the problem of increased antimicrobial resistance, we developed a glycoconjugate vaccine comprised of O-polysaccharides (OPS) of the four most prevalent serotypes of Klebsiella pneumoniae (KP) linked to recombinant flagellin types A and B (rFlaA and rFlaB) of Pseudomonas aeruginosa (PA). Flagellin is the major subunit of the flagellar filament. Flagella A and B, essential virulence factors for PA, are glycosylated with different glycans. We previously reported that while both rFlaA and rFlaB were highly immunogenic, only the rFlaB antisera reduced PA motility and protected mice from lethal PA infection in a mouse model of thermal injury. Since recombinant flagellin is not glycosylated, we examined the possibility that the glycan on native FlaA (nFlaA) might be critical to functional immune responses. We compared the ability of nFlaA to that of native, deglycosylated FlaA (dnFlaA) to induce functionally active antisera. O glycan was removed from nFlaA with trifluoromethanesulfonic acid. Despite the similar high-titered anti-FlaA antibody levels elicited by nFlaA, rFlaA, and dnFlaA, only the nFlaA antisera inhibited PA motility and protected mice following lethal intraperitoneal bacterial challenge. Both the protective efficacy and carrier protein function of nFlaA were retained when conjugated to KP O1 OPS. We conclude that unlike the case with FlaB O glycan, the FlaA glycan is an important epitope for the induction of functionally active anti-FlaA antibodies.
摘要：
为了解决抗菌素耐药性增加的问题，我们开发了一种糖缀合物疫苗，该疫苗由肺炎克雷伯菌（KP）的四种最常见血清型的O-多糖（OPS）与铜绿假单胞菌（PA）的重组鞭毛蛋白A和B（rFlaA和rFlaB）连接。鞭毛蛋白是鞭毛丝的主要亚基。鞭毛A和B,PA的基本毒力因子，用不同的聚糖糖基化。我们以前报道，虽然rFlaA和rFlaB都具有高度免疫原性，在热损伤小鼠模型中，只有rFlaB抗血清会降低PA的运动性并保护小鼠免受致命的PA感染。由于重组鞭毛蛋白没有糖基化，我们检查了天然FlaA（nFlaA）上的聚糖可能对功能性免疫应答至关重要的可能性。我们比较了nFlaA和本地人的能力，去糖基化的FlaA(dnFlaA)诱导功能活性抗血清。用三氟甲磺酸从nFlaA中除去O聚糖。尽管nFlaA引发的高滴度抗FlaA抗体水平相似，rFlaA,和dnFlaa,在致命的腹膜内细菌攻击后，只有nFlaA抗血清抑制PA运动并保护小鼠。当与KPO1OPS缀合时，nFlaA的保护功效和载体蛋白功能均得到保留。我们得出的结论是，与FlaBO聚糖的情况不同，FlaA聚糖是诱导功能活性抗FlaA抗体的重要表位。
