Molecular and functional characterization of turkey interferon

Area of Science:

• Immunology
• Virology
• Molecular Biology

Background:

• Interferons (IFNs) are critical antiviral proteins.
• The role of turkey interferon (TkIFN) in innate immunity is not fully understood.
• Nitric oxide (NO) and interleukin-8 (IL-8) are key inflammatory mediators.

Purpose of the Study:

• To characterize the recombinant turkey interferon (TkIFN) protein.
• To investigate the role of TkIFN in modulating macrophage functions, specifically nitric oxide (NO) and interleukin-8 (IL-8) production.
• To compare the inflammatory potential of TkIFN with mammalian alpha/beta IFNs.

Main Methods:

• TkIFN gene cloning and recombinant protein expression.
• Induction of TkIFN mRNA expression using reoviral double-stranded RNA in fibroblasts.
• Assessing TkIFN's antiviral activity in a species-specific manner.
• Stimulating bone marrow macrophages with TkIFN and lipopolysaccharide (LPS) to measure NO and IL-8 production.

Main Results:

• Recombinant TkIFN exhibited species-specific antiviral activity.
• TkIFN, in synergy with LPS, significantly induced NO production in bone marrow macrophages.
• TkIFN alone did not induce significant NO production, indicating it provides a necessary co-stimulatory signal.
• TkIFN enhanced LPS-induced expression of the proinflammatory cytokine IL-8, contrasting with mammalian IFNs.
• TkIFN's pro-inflammatory activity was demonstrated through IL-8 upregulation.

Conclusions:

• Turkey interferon (TkIFN) plays a role in innate immunity by co-stimulating NO production in macrophages.
• TkIFN possesses pro-inflammatory properties, distinct from the anti-inflammatory effects of mammalian alpha/beta IFNs.
• TkIFN may contribute to inflammatory conditions in turkeys due to its ability to induce IL-8 expression.