A trimeric anti-HER2/neu ScFv and tumor necrosis factor-alpha fusion protein induces HER2/neu signaling and facilitates repair of injured epithelia

J Pharmacol Exp Ther. 2006 Mar;316(3):983-91. doi: 10.1124/jpet.105.095513. Epub 2005 Nov 15.

Abstract

Tumor necrosis factor (TNF)-alpha genetically fused to the carboxyl terminus of a single-chain Fv (ScFv) antibody specific for the human HER2/neu (anti-HER2/neu ScFv-TNF-alpha) forms a homotrimeric structure that retains both TNF-alpha activity and the ability to bind HER2/neu. In contrast to anti-HER2/neu IgG3, anti-HER2/neu ScFv-TNF-alpha induces potent HER2/neu signaling, activating the downstream mitogen-activated protein kinase (MAPK) and Akt pathways in SKBR3 cells. Activation of MAPK and Akt by anti-HER2/neu ScFv-TNF-alpha inhibited the apoptosis of SKBR3 cells induced by actinomycin D. Remarkably, anti-HER2/neu ScFv-TNF-alpha facilitated the repair of injured epithelia. Accelerated wound healing required binding to HER2/neu but not TNF-alpha activity since anti-HER2/neu ScFv-TNF-alpha (S147Y), containing a mutant TNF-alpha with significantly decreased biological activity, demonstrated equivalent ability to facilitate wound healing and soluble HER2/neu inhibited the effect. These results suggest that trimeric anti-HER2/neu ScFv has the potential to facilitate wound healing. In addition, fusion with TNF-alpha provides a novel approach to producing polymeric antibodies.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies / pharmacology*
  • Apoptosis / drug effects
  • CHO Cells
  • Caco-2 Cells
  • Cricetinae
  • Epithelium / physiology
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Humans
  • Immunoglobulin Fragments / pharmacology*
  • Phosphatidylinositol 3-Kinases / physiology
  • Phosphorylation
  • Proto-Oncogene Proteins c-akt / metabolism
  • Receptor, ErbB-2 / antagonists & inhibitors*
  • Receptor, ErbB-2 / immunology
  • Receptor, ErbB-2 / metabolism
  • Recombinant Fusion Proteins / pharmacology*
  • Tumor Necrosis Factor-alpha / pharmacology*
  • Wound Healing / drug effects*

Substances

  • Antibodies
  • Immunoglobulin Fragments
  • Recombinant Fusion Proteins
  • Tumor Necrosis Factor-alpha
  • immunoglobulin Fv
  • Phosphatidylinositol 3-Kinases
  • Receptor, ErbB-2
  • Proto-Oncogene Proteins c-akt
  • Extracellular Signal-Regulated MAP Kinases