Distribution and expression of recombinant plasmid encoding chicken interleukin-2

Area of Science:

• Molecular Biology
• Immunology
• Veterinary Medicine

Background:

• Chicken interleukin-2 (ChIL-2) is a cytokine crucial for immune responses.
• Plasmid DNA delivery offers a potential method for gene expression in vivo.
• Understanding plasmid DNA distribution and expression is vital for developing gene-based therapies.

Purpose of the Study:

• To investigate the distribution and expression of a plasmid DNA encoding chicken interleukin-2 fused with enhanced green fluorescent protein (pCI-ChIL-2-EGFP) after intramuscular injection in chickens.
• To determine the duration and location of plasmid DNA presence and gene expression in chickens.

Main Methods:

• Intramuscular (i.m.) injection of pCI-ChIL-2-EGFP plasmid DNA in chickens.
• Detection of plasmid DNA in serum and various organs using molecular methods.
• Assessment of enhanced green fluorescent protein (EGFP) expression in vitro and in vivo using cell culture, RT-PCR, ELISA, and fluorescence microscopy.

Main Results:

• Plasmid DNA was detected in serum from 2 hours to 7 days post-inoculation (p.i.) and in organs including heart, liver, lung, spleen, bursa, and inoculated muscle up to 19 days p.i.
• EGFP expression was observed in transfected cells in vitro and in vivo.
• In vivo EGFP expression was detected from 8 hours to 14 days p.i., peaking at 5 days p.i. in the injected muscle.

Conclusions:

• Intramuscular administration of pCI-ChIL-2-EGFP plasmid DNA results in broad distribution throughout the body.
• Sustained expression of the ChIL-2-EGFP fusion gene occurs at the injection site for an extended period.
• This study demonstrates the feasibility of using intramuscular plasmid DNA delivery for gene expression in chickens.