Thus, the present study was designed to evaluate the anti-tumor effectiveness of the combinatorial therapy encasing oncolytic vector AdV5/3-D24-ICOSL-CD40L, expressing two powerful co-stimulatory molecules: inducible co-stimulator ligand (ICOSL) and CD40 ligand (CD40Land CD154) (25), with an anti-PD-1 monoclonal antibody, in both immunodeficient and humanized xenografted mesothelioma H266 mouse models. The gene discussed is ICOSLG; the disease is mesothelioma.