title: Fc-mOX40L fusion protein produces complete remission and enhanced survival in 2 murine tumor models.
abstract: OX40L is a member of the tumor necrosis factor superfamily that provides a costimulatory signal to CD4+ and CD8+ T cells while inhibiting the effects of suppressive CD4+ CD25+ regulatory T cells. Because of this dual activity, OX40L may provide significant antitumor immunity in tumor-bearing mice. To study its clinical potential, a fusion protein consisting of mOX40L linked to the C-terminus of the Fc fragment of immunoglobulin was genetically engineered. After demonstrating its potency in vitro, several assays were performed to evaluate its antitumor effect in comparison to the OX40 agonist antibody OX86. Dosing studies in Colon 26-bearing and renal cell carcinoma (RENCA)-bearing mice showed that although OX86 produced modest tumor regression, Fc-mOX40L produced complete remission in both tumor models. Survival studies confirmed these results and showed that Fc-mOX40L treatment produced lasting responses throughout the 5-month observation period. Flow cytometric analysis of treated and untreated tumors and tumor-draining lymph nodes identified a qualitative difference in the activity of Fc-mOX40L compared with OX86 treatment as evidenced by differences in lymphoid and macrophage populations. These studies reflect the profound therapeutic potential of Fc-mOX40L, which substantially exceeds the agonist antibody OX86 in ability to produce complete tumor remissions and promote long-term survival in solid tumor models.
authors.affiliation: Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
authors.forename: Rebecca E
authors.initials: RE
authors.lastname: Sadun
authors.forename: Wen-En
authors.initials: WE
authors.lastname: Hsu
authors.forename: Nan
authors.initials: N
authors.lastname: Zhang
authors.forename: Yu-Chih
authors.initials: YC
authors.lastname: Nien
authors.forename: Scott A
authors.initials: SA
authors.lastname: Bergfeld
authors.forename: Helen
authors.initials: H
authors.lastname: Sabzevari
authors.forename: M E Christine
authors.initials: ME
authors.lastname: Lutsiak
authors.forename: Leslie
authors.initials: L
authors.lastname: Khawli
authors.forename: Peisheng
authors.initials: P
authors.lastname: Hu
authors.forename: Alan L
authors.initials: AL
authors.lastname: Epstein
mesh_terms: D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002292:Carcinoma, Renal Cell / Q000188:drug therapy* / Q000276:immunology / Q000473:pathology; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000276:immunology / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D007680:Kidney Neoplasms / Q000188:drug therapy* / Q000276:immunology / Q000473:pathology; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D053278:OX40 Ligand / Q000235:genetics / Q000276:immunology / Q000627:therapeutic use; D011961:Receptors, Fc / Q000235:genetics / Q000276:immunology / Q000627:therapeutic use; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology / Q000627:therapeutic use; D012074:Remission Induction; D015398:Signal Transduction
chemical_list: D053278:OX40 Ligand; D011961:Receptors, Fc; D011993:Recombinant Fusion Proteins