Cellular immune response induced by surface immunogenic protein with AbISCO-100 adjuvant vaccination decreases group...

Area of Science:

• Bacteriology
• Immunology
• Vaccinology

Background:

• Group B Streptococcus (GBS) is a leading cause of neonatal bacterial infections, premature birth, and stillbirth.
• Currently, no approved vaccines exist for GBS, necessitating the development of effective preventative strategies.
• The GBS Surface Immunogenic Protein (SIP) is a conserved antigen across serotypes, showing promise as a vaccine candidate.

Purpose of the Study:

• To evaluate the efficacy of a novel vaccine combining rSIP and AbISCO-100 adjuvant against GBS vaginal colonization in a mouse model.
• To investigate the induction of antibodies with opsonophagocytic activity and cellular immunity following immunization.
• To assess the protective potential of passive transfer of immune components from immunized mice.

Main Methods:

• Immunization of mice with a vaccine comprising rSIP and AbISCO-100 adjuvant.
• Assessment of GBS vaginal colonization levels post-vaccination.
• Measurement of antibody opsonophagocytic activity.
• Passive transfer of immune sera and T-cells to assess cellular immunity.

Main Results:

• The rSIP and AbISCO-100 vaccine significantly reduced GBS vaginal colonization in mice.
• Immunization induced antibodies exhibiting opsonophagocytic activities.
• Passive transfer of sera and T-cells from immunized mice conferred protection against GBS colonization in recipient mice.
• This study provides the first evidence of cellular immunity associated with an rSIP-based vaccine.

Conclusions:

• A vaccine combining rSIP and AbISCO-100 demonstrates efficacy in reducing GBS vaginal colonization in a mouse model.
• The vaccine elicits functional antibodies and induces cellular immunity, suggesting a multifaceted protective mechanism.
• These findings support the further development of SIP-based vaccines, potentially including cellular immunity components, for GBS prevention.