A trimeric anti-HER2/neu ScFv and tumor necrosis factor-alpha fusion protein induces HER2/neu signaling and facilitates repair of injured epithelia.
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.
Huang
Tzu-Hsuan
TH
Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, Box 951489, Los Angeles, CA 90095-1489, USA. thhhuang@ucla.edu
Morrison
Sherie L
SL
D000818:Animals; D000906:Antibodies / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D016466:CHO Cells; D018938:Caco-2 Cells; D006224:Cricetinae; D004848:Epithelium / Q000502:physiology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D006801:Humans; D007128:Immunoglobulin Fragments / Q000494:pharmacology*; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000276:immunology / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D014945:Wound Healing / Q000187:drug effects*
D000906:Antibodies; D048049:Extracellular Signal-Regulated MAP Kinases; D007128:Immunoglobulin Fragments; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D018719:Erb-b2 Receptor Tyrosine Kinases; D011993:Recombinant Fusion Proteins; D014409:Tumor Necrosis Factor-alpha; C055966:immunoglobulin Fv