Using multivalent adenoviral vectors for HIV vaccination.

Area of Science:

• Vaccinology and immunology
• Viral vector technology
• Molecular biology

Background:

• Adenoviral (Ad) vectors are versatile platforms for vaccine development, traditionally using transgene expression.
• Presenting multiple antigens is crucial for optimal vaccine efficacy, as seen in preclinical polyvalent vaccines.
• Displaying antigens on the Ad capsid surface (antigen capsid-incorporation) can induce robust humoral immunity.

Purpose of the Study:

• To engineer adenoviral vectors capable of displaying multiple antigens simultaneously on the capsid surface.
• To investigate the manipulation of the adenoviral hexon protein's Hypervariable Region 1 (HVR1) for antigen display.
• To create and evaluate the first dual-antigen displaying adenoviral hexon particles.

Main Methods:

• Engineered adenoviral vectors by manipulating hexon HVR1, HVR2, and HVR5.
• Incorporated a seven amino acid region of HIV glycoprotein 41 into HVR1.
• Co-displayed His6 tags within HVR2 or HVR5 alongside the HIV antigen.

Main Results:

• Successfully created multivalent adenoviral vectors displaying both HIV antigen and His6 tags within a single particle.
• Demonstrated the viability of these vectors in presenting dual antigens on the virion surface.
• Mouse immunizations confirmed the induction of HIV and His6 epitope-specific humoral immune responses.

Conclusions:

• Multivalent adenoviral vectors displaying dual antigens are feasible and effective.
• Capsid incorporation of antigens, including novel sites like HVR1, is a viable strategy for vaccine design.
• These engineered vectors hold promise for developing advanced vaccines against infectious diseases like HIV.