Immunization with Multiple Virulence Factors Provides Maternal and Neonatal Protection against Group B Streptococcus...

Area of Science:

• Bacteriology
• Immunology
• Vaccinology

Background:

• Group B streptococcus (GBS) is a major cause of neonatal infections and adverse pregnancy outcomes.
• Current GBS vaccines are limited, necessitating novel approaches.
• Conserved bacterial virulence factors are potential vaccine candidates.

Purpose of the Study:

• To investigate the efficacy of intranasal immunization with six conserved GBS virulence factors (GBSV6) for serotype-independent protection against GBS.
• To evaluate systemic and mucosal immune responses induced by GBSV6.
• To assess the protective effects of GBSV6 in dams and their offspring.

Main Methods:

• Mice were intranasally immunized with GBSV6.
• Systemic and vaginal antibody and T cell responses were measured.
• Mice were challenged with various GBS serotypes to assess mortality and vaginal colonization.
• Protection of newborn mice from immunized dams was evaluated.

Main Results:

• Intranasal GBSV6 induced robust systemic and vaginal antibody and T cell responses.
• Immunization reduced GBS-induced mortality and vaginal colonization in mice across multiple serotypes.
• Newborn mice from immunized dams were protected against GBS challenge.
• Intranasal immunization provided long-lasting immunity and was superior to intramuscular immunization in reducing vaginal GBS colonization.

Conclusions:

• Intranasal immunization with GBSV6 induces serotype-independent, long-lasting immunity.
• This strategy effectively protects against GBS infection systemically and vaginally in dams.
• GBSV6 immunization prevents GBS-related mortality in newborns, offering a promising vaccine development strategy.