Production of human alpha-interferon in silkworm using a baculovirus vector

Area of Science:

• Biotechnology
• Molecular Biology
• Entomology

Background:

• Microbial systems are common for foreign gene product manufacturing.
• Multicellular organisms, including silkworms, present an economical alternative for producing foreign gene products.
• Bombyx mori nuclear polyhedrosis virus (BmNPV) is a potential candidate for gene expression due to its ease of culture and low cost.

Purpose of the Study:

• To develop a baculovirus vector for introducing foreign genes into silkworms.
• To express human alpha-interferon (IFN-alpha) in silkworms using a recombinant BmNPV vector.

Main Methods:

• Identified and cloned the BmNPV polyhedrin gene.
• Constructed a recombinant plasmid with a polylinker linked to the polyhedrin promoter for foreign gene insertion.
• Co-transfected the recombinant plasmid and BmNPV genomic DNA into BM-N cells.
• Isolated recombinant viruses via plaque assay and confirmed replication in silkworm larvae.

Main Results:

• Successfully generated recombinant BmNPV carrying the IFN-alpha gene.
• Recombinant virus replicated effectively in silkworm larvae.
• Silkworm hemolymph contained up to 5 X 10(7) units (approx. 50 micrograms) of synthesized interferon.

Conclusions:

• BmNPV serves as a viable expression vector for foreign gene products in silkworms.
• This silkworm-based expression system offers a cost-effective method for producing biopharmaceuticals like interferon.
• The narrow host range of BmNPV is advantageous for environmental safety compared to other baculoviruses.