Mice immunization with live lactococci displaying a surface anchored HPV-16 E7 oncoprotein.

Area of Science:

• Biotechnology
• Immunology
• Microbiology

Background:

• The E7 oncoprotein of human papillomavirus-16 (HPV-16) is a key target for cervical cancer (CxCa) therapeutic vaccines.
• Developing effective and safe vaccine delivery systems is crucial for combating HPV-16-associated cancers.

Purpose of the Study:

• To engineer a live, food-grade bacterial delivery system for the HPV-16 E7 protein.
• To evaluate the immunogenicity of cell surface-displayed E7 protein in a preclinical model.

Main Methods:

• Utilized the nisin-controlled expression system in Lactococcus lactis to anchor the E7 protein to the bacterial cell wall.
• Administered recombinant Lactococcus lactis intranasally to mice.
• Assessed the induction of an HPV-16 E7-specific immune response.

Main Results:

• Achieved efficient cell wall anchoring of the E7 protein in Lactococcus lactis.
• Demonstrated that intranasal administration of these recombinant bacteria induced a specific immune response against HPV-16 E7.
• This study is the first to report E7 cell wall anchoring in L. lactis.

Conclusions:

• Live, food-grade Lactococcus lactis can be engineered to display the HPV-16 E7 protein on its cell surface.
• This bacterial display system effectively elicits an HPV-16 E7-specific immune response in vivo.
• This represents a promising step towards developing live bacterial vaccines for cervical cancer therapy.