T0001, a variant of TNFR2-Fc fusion protein, exhibits improved Fc effector functions through increased binding to membrane-bound TNFα

PLoS One. 2017 May 19;12(5):e0177891. doi: 10.1371/journal.pone.0177891. eCollection 2017.

Abstract

T0001 is a recombinant human TNFR-Fc fusion protein mutant; it exhibits higher affinity to TNFα than etanercept and is now being tested in a Phase 1 study in China (ClinicalTrials.gov Identifier: NCT02481180). T0001 can inhibit the binding of soluble TNFα (sTNFα) or membrane-bound TNFα (mTNFα) to TNF receptors. When bound to mTNFα, the Fc-bearing TNFα antagonists have the potential to induce Fc-mediated effects, such as antibody-dependent cellular cytotoxicity (ADCC) and complement-mediated cytotoxicity (CDC) as well as outside-to-inside signals (apoptosis mainly). Recent studies have shown that ADCC may also play an important role in Crohn's disease (CD) and ulcerative colitis (UC). In this study, T0001 presented a higher binding activity on mTNFα than etanercept and similar binding activity with adalimumab and infliximab. Upon the addition of sTNFα, adalimumab and infliximab showed significantly increased binding to FcγRIIIa and C1q than T0001 and etanercept. T0001 exhibited significantly higher ADCC and CDC activity than etanercept, and the potency and the reporter response of T0001 were very close to adalimumab and infliximab in ADCC reporter gene assays. And the similar potency of T0001 was also corroborated by PMBC-based ADCC assay. T0001, but not etanercept could induce apoptosis, while adalimumab and infliximab were more effective. These results suggest that T0001 may not only exert improved efficacy in treating rheumatoid arthritis (RA) because of its high affinity to sTNFα but also has a therapeutic potential in CD and UC due to its increased binding to mTNFα with resultant Fc-associated functions (ADCC, in particular) and improved apoptosis.

MeSH terms

  • Animals
  • Antibodies, Monoclonal / pharmacology*
  • Antibody-Dependent Cell Cytotoxicity
  • Apoptosis / drug effects*
  • Cell Membrane / metabolism*
  • Cells, Cultured
  • China
  • Immunosuppressive Agents / pharmacology
  • Mice
  • Protein Binding
  • Receptors, IgG / genetics
  • Receptors, IgG / metabolism*
  • Receptors, Tumor Necrosis Factor, Type II / genetics
  • Receptors, Tumor Necrosis Factor, Type II / metabolism*
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism*
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / metabolism*

Substances

  • Antibodies, Monoclonal
  • FcgammaRIIIA protein, mouse
  • Immunosuppressive Agents
  • Receptors, IgG
  • Receptors, Tumor Necrosis Factor, Type II
  • Recombinant Fusion Proteins
  • Tumor Necrosis Factor-alpha

Associated data

  • ClinicalTrials.gov/NCT02481180

Grants and funding

This project was supported by internal funds of Shanghai Fudan-Zhangjiang Bio-Pharmaceutical Co, Ltd. (China). The funder provided support in the form of salaries for authors, YShen, GL, CG, BC, AC, HL, BG, CL, JW, TY and YSu, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the 'author contributions' section.