System for efficient helper-dependent minimal adenovirus construction and rescue

Area of Science:

• Gene Therapy
• Molecular Biology
• Virology

Background:

• Helper-dependent minimal adenoviral vectors offer advantages over first-generation vectors, including reduced toxicity and prolonged transgene expression.
• These vectors retain only essential adenovirus cis elements, accommodating large foreign DNA inserts up to 36 kb.

Purpose of the Study:

• To develop a streamlined system for the routine construction and efficient rescue of minimal adenoviral vectors.
• To create versatile cosmid cloning vectors (pMV and pMVX) facilitating the generation of these advanced gene therapy vectors.

Main Methods:

• Development of cosmid cloning vectors (pMV and pMVX) with I-SceI recognition sites for precise genome release.
• Utilizing pMV for direct insertion of large therapeutic DNA (26-36 kb) and pMVX for backbone replacement with smaller inserts (1-26 kb).
• Employing a Cre/lox-based helper system for efficient rescue and amplification of minimal adenoviruses.

Main Results:

• Successfully constructed minimal adenoviral vectors with insert sizes ranging from 1.5 to 16 kb.
• Demonstrated efficient rescue and high-titer amplification of minimal adenoviruses using the developed system.
• Confirmed stability of vectors containing the X-chromosomal backbone during amplification.

Conclusions:

• The developed cosmid cloning vector system simplifies the construction and rescue of minimal adenoviral vectors.
• This efficient system is valuable for the further development and application of minimal adenoviral vectors in gene therapy.
• The system supports the creation of vectors with varying insert sizes and backbone configurations.