Chimeric and humanized antibodies with specificity for the CD33 antigen

J Immunol. 1992 Feb 15;148(4):1149-54.

Abstract

L and H chain cDNAs of M195, a murine mAb that binds to the CD33 Ag on normal and leukemic myeloid cells, were cloned. The cDNAs were used in the construction of mouse/human IgG1 and IgG3 chimeric antibodies. In addition, humanized antibodies were constructed which combined the complementarity-determining regions of the M195 antibody with human framework and constant regions. The human framework was chosen to maximize homology with the M195 V domain sequence. Moreover, a computer model of M195 was used to identify several framework amino acids that are likely to interact with the complementarity-determining regions, and these residues were also retained in the humanized antibodies. Unexpectedly, the humanized IgG1 and IgG3 M195 antibodies, which have reshaped V regions, have higher apparent binding affinity for the CD33 Ag than the chimeric or mouse antibodies.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Monoclonal / genetics*
  • Antibodies, Monoclonal / immunology
  • Antibody Affinity
  • Antigens, CD / immunology*
  • Antigens, Differentiation, Myelomonocytic / immunology*
  • Base Sequence
  • Cloning, Molecular
  • Humans
  • Immunoglobulin G / genetics*
  • Immunoglobulin G / immunology
  • Immunoglobulin Variable Region / genetics
  • Mice
  • Molecular Sequence Data
  • Recombinant Fusion Proteins / immunology*
  • Sialic Acid Binding Ig-like Lectin 3

Substances

  • Antibodies, Monoclonal
  • Antigens, CD
  • Antigens, Differentiation, Myelomonocytic
  • CD33 protein, human
  • Cd33 protein, mouse
  • Immunoglobulin G
  • Immunoglobulin Variable Region
  • Recombinant Fusion Proteins
  • Sialic Acid Binding Ig-like Lectin 3

Associated data

  • GENBANK/L19643
  • GENBANK/L19644
  • GENBANK/L19645
  • GENBANK/L19646
  • GENBANK/L19647
  • GENBANK/M65172
  • GENBANK/M65173
  • GENBANK/M65174
  • GENBANK/M83098
  • GENBANK/M83099