K20

Antibody Name: K20 (VH SGIIB/DFL16/JH2 | VL kV/Jk1)
References: Poul, M., Ticchioni, M., Bernard, A. and Lefranc, M. "Inhibition of T cell activation with a humanized anti-B1 integrin chain mAb" Mol. Immunol. (1995) 32:101-116.
Donor Antibody: mouse
Acceptor Antibody: IgG1 | k
Antigen: β1 chain (CD29) of human integrins (VLA family)
Laboratory: LIGM and INSERM, France
Design: Humanisation based solely on sequence and not structure.
Frameworks: VH F1 | VL REI (as in Campath-1H).
CDRs: All 6 VH and VL, Kabat Definition.
Backmutations: VH R94- (deletion in mouse CDR-H3) VL M4L Y49R E105V
Binding: 2.5-fold reduction in binding compared to chimaeric as measured by immunofluorescence staining and competition binding. Functional properties of the original mouse mAb were retained.
Expression: Fab in E. coli JM101 cells, whole mAbs in NS0 cells
Comment: Argue that VH and VL FRs can come from different mAbs since the binding site depends on only a few conserved (canonical) residues.
Different epitope to mouse mAbs 4B4, TS2/16, A1A5
Clinical Indication: Therapeutic immunosupression

explanation of symbols and abbreviations

José Saldanha © 1997-8. Birkbeck College, London WC1E 7HX.