Opsonic Activity of Conservative Versus Variable Regions of the Group A Streptococcus M Protein

Autor: Chuankai Dai, Zeinab G. Khalil, Waleed M. Hussein, Jieru Yang, Xiumin Wang, Lili Zhao, Robert J. Capon, Istvan Toth, Rachel J. Stephenson
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: Vaccines, Vol 8, Iss 2, p 210 (2020)
Druh dokumentu: article
ISSN: 2076-393X
DOI: 10.3390/vaccines8020210
Popis: Group A Streptococcus (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.
Databáze: Directory of Open Access Journals