Murine Leukemia Virus Envelope Protein in Transgenic-Mouse Serum Blocks Infection In Vitro

Volume 70, no. 3, p. 1882–1889, 1996. We reported that Fv4 serum inhibited infection of murine leukemia virus (MuLV) in vitro. In subsequent experiments, we have not reproduced the inhibitory effect shown in Tables 1 and 2. In particular, some Fv4 sera did not inhibit Moloney MuLV, whereas other sera, including some from control FVB/N mice, did inhibit when used at high concentrations (1/3 to 1/10). The data in Tables 1 and 2 were obtained with a pool of Fv4 sera that presumably contained an inhibitor unrelated to Fv4. Thus, while Fv4 Env gp70 is clearly secreted and binds to the ecotropic receptor, we cannot conclude that secreted Fv4 Env is sufficient to block infection or that it contributes to the mechanism of Fv4 resistance. Therefore, we retract this article. We regret any inconvenience this may have caused.