Study on the glycoprotein nature of chicken IFNs by chemical cleavage and inhibition of glycosylation.

: The considerable molecular heterogeneity of chicken IFNs suggested the possible glycoprotein nature of these IFNs. The carbohydrate-specific oxidation and cleavage by neuraminidase indicated that fibroblast IFN may contain sugar moieties. Among the antimetabolites preventing glycosylation, monensin diminished IFN production. However, since it had the same effect on unglycosylated human leukocyte IFN, the drug very probably blocks intracellular transport. It rather proved that chicken IFNs are also secretory proteins. Tunicamycin diminished the formation of leukocyte IFN, but the decrease in titre of this IFN is due to the inhibition of protein synthesis. It is suggested that chicken fibroblast IFN is a glycoprotein, while leukocyte IFN lacks a sugar moiety. The IFN produced on induction with mitogen is closely related to leukocyte IFN, and therefore it seems that the chicken IFN system does not involve the conventional gamma type.