A new interferon, limitin, displays equivalent immunomodulatory and antitumor activities without myelosuppressive properties as compared with interferon-alpha.

Objective: Limitin is a new member of type I interferon (IFN) identified with an expression cloning based on the growth suppression of a myelomonocytic leukemia cell line WEHI3. Although limitin uses the IFN-alpha/beta receptor, its signal transduction pathways to express the antiviral effects are different from those of IFN-alpha. To clarify the characteristics of limitin, we compared the biological activities of limitin, such as the antiviral, immunomodulatory, antitumor, and myelosuppressive effects, with IFN-alpha.