Mouse guanylate-binding proteins of the chromosome 3 cluster do not mediate antiviral activity in vitro or in mouse models of infection.

Dynamin-like GTPase proteins, including myxoma (Mx) and guanylate-binding proteins (GBPs), are among the many interferon stimulated genes induced following viral infections. While studies report that human (h)GBPs inhibit different viruses in vitro, few have convincingly demonstrated that mouse (m)GBPs mediate antiviral activity, although mGBP-deficient mice have been used extensively to define their importance in immunity to diverse intracellular bacteria and protozoa. Herein, we demonstrate that individual (overexpression) or collective (knockout (KO) mice) mGBPs of the chromosome 3 cluster (mGBPchr3) do not inhibit replication of five viruses from different virus families in vitro, nor do we observe differences in virus titres recovered from wild type versus mGBPchr3 KO mice after infection with three of these viruses (influenza A virus, herpes simplex virus type 1 or lymphocytic choriomeningitis virus). These data indicate that mGBPchr3 do not appear to be a major component of cell-intrinsic antiviral immunity against the diverse viruses tested in our studies.