Dai Chuankai, Khalil Zeinab G, Hussein Waleed M, Yang Jieru, Wang Xiumin, Zhao Lili, Capon Robert J, Toth Istvan, Stephenson Rachel J
School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, QLD 4072, Australia.
Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072, Australia.
Vaccines (Basel). 2020 May 7;8(2):210. doi: 10.3390/vaccines8020210.
Group A (GAS) and GAS-associated infections are a global challenge, with no licensed GAS vaccine on the market. The GAS M protein is a critical virulence factor in the fight against GAS infection, and it has been a primary target for GAS vaccine development. Measuring functional opsonic antibodies against GAS is an important component in the clinical development path for effective vaccines. In this study, we compared the opsonic activity of two synthetic, self-adjuvanting subunit vaccines containing either the J8- or 88/30-epitope in Swiss outbred mice using intranasal administration. Following primary immunization and three boosts, sera were assessed for IgG activity using ELISA, and opsonization activity against seven randomly selected clinical isolates of GAS was measured. Vaccine constructs containing the conservative J8-epitope showed significant opsonic activity against six out of the seven GAS clinical isolates, while the vaccine containing the variable 88/30-epitope did not show any significant opsonic activity.
A组链球菌(GAS)及与GAS相关的感染是一项全球性挑战,目前市场上尚无获批的GAS疫苗。GAS M蛋白是对抗GAS感染的关键毒力因子,一直是GAS疫苗研发的主要靶点。检测针对GAS的功能性调理素抗体是有效疫苗临床研发过程中的一个重要组成部分。在本研究中,我们在瑞士远交系小鼠中使用鼻内给药的方式,比较了两种含有J8或88/30表位的合成自佐剂亚单位疫苗的调理活性。初次免疫及三次加强免疫后,使用酶联免疫吸附测定(ELISA)评估血清中的IgG活性,并测定针对七株随机选择的GAS临床分离株的调理活性。含有保守J8表位的疫苗构建体对七株GAS临床分离株中的六株显示出显著的调理活性,而含有可变88/30表位的疫苗未显示出任何显著的调理活性。