Establishment of FUT8 knockout Chinese hamster ovary cells: an ideal host cell line for producing completely defucosylated antibodies with enhanced antibody-dependent cellular cytotoxicity

Biotechnol Bioeng. 2004 Sep 5;87(5):614-22. doi: 10.1002/bit.20151.


To generate industrially applicable new host cell lines for antibody production with optimizing antibody-dependent cellular cytotoxicity (ADCC) we disrupted both FUT8 alleles in a Chinese hamster ovary (CHO)/DG44 cell line by sequential homologous recombination. FUT8 encodes an alpha-1,6-fucosyltransferase that catalyzes the transfer of fucose from GDP-fucose to N-acetylglucosamine (GlcNAc) in an alpha-1,6 linkage. FUT8(-/-) cell lines have morphology and growth kinetics similar to those of the parent, and produce completely defucosylated recombinant antibodies. FUT8(-/-)-produced chimeric anti-CD20 IgG1 shows the same level of antigen-binding activity and complement-dependent cytotoxicity (CDC) as the FUT8(+/+)-produced, comparable antibody, Rituxan. In contrast, FUT8(-/-)-produced anti-CD20 IgG1 strongly binds to human Fcgamma-receptor IIIa (FcgammaRIIIa) and dramatically enhances ADCC to approximately 100-fold that of Rituxan. Our results demonstrate that FUT8(-/-) cells are ideal host cell lines to stably produce completely defucosylated high-ADCC antibodies with fixed quality and efficacy for therapeutic use.

MeSH terms

  • Alleles
  • Animals
  • Antibodies, Monoclonal / biosynthesis
  • Antibody-Dependent Cell Cytotoxicity*
  • Antigens, CD20 / genetics
  • Antigens, CD20 / immunology
  • CHO Cells
  • Carbohydrate Sequence
  • Cricetinae
  • Cricetulus
  • Enzyme-Linked Immunosorbent Assay
  • Fucosyltransferases / genetics*
  • Gene Targeting
  • Gene Transfer Techniques
  • Genetic Vectors
  • Humans
  • Immunoglobulin G / biosynthesis
  • Oligosaccharides / chemistry
  • Recombinant Fusion Proteins / immunology
  • Recombinant Fusion Proteins / metabolism
  • Tumor Cells, Cultured


  • Antibodies, Monoclonal
  • Antigens, CD20
  • Immunoglobulin G
  • Oligosaccharides
  • Recombinant Fusion Proteins
  • Fucosyltransferases
  • Glycoprotein 6-alpha-L-fucosyltransferase