Another oncolytic vaccinia virus, VV-GMCSF-Lact, with the insertion of GM-CSF gene, was shown to hold a high level of this protein in the culture medium of tumor cells infected with recombinants VV-GMCSF-Lact and VV-GMCSF-dGF (the same virus without lactaptin gene insertion); meanwhile, no GM-CSF was detected in the same conditions with the wild-type virus L-IVP [113]. The gene discussed is CSF2; the disease is neoplasm.