Expression of biologically active recombinant equine interferon-gamma in Escherichia coli.

This research demonstrates for the first time that a prokaryote-derived recombinant equine interferon-gamma has an important antiviral activity. The work involved cloning the gene for equine interferon-gamma into Escherichia coli and testing its antiviral activity in an equine fetal kidney cell line system.

Cloning and Expression of Equine Interferon Gamma

• The researchers began by cloning the gene for equine interferon gamma (EIFN-gamma) into a commonly used bacterial model organism, E. coli.
• This process uses the mechanisms of the E. coli to express the external EIFN-gamma gene, effectively turning the bacteria into a small factory to produce this protein.

Assessment of Antiviral Activity

• The researchers used a specially developed virus, recombinant Vesicular Stomatitis Virus expressing green fluorescence protein (rVSV-GFP), to test the antiviral activity of the produced IFN-gamma.
• This virus was introduced into the EFK-78 equine kidney cell line, and the expression of the green fluorescent protein (GFP) served as a marker for the levels of viral infection in these cells.
• The researchers found that when the cells were treated with EIFN-gamma, the level of GFP expression decreased, suggesting that the protein has antiviral activity.

Significance of the Findings

• The successful production of active equine interferon-gamma in a bacterial system opens up new possibilities for studying the protein’s effects on the immune response.
• The findings suggest that it may be possible to produce large quantities of biologically active EIFN-gamma for research and therapeutic purposes, such as developing treatments for viral infections in horses.