Molecular characterization of a human monoclonal antibody to B antigen in ABO blood type.
A human anti-B antibody of clone BT97 was obtained from a healthy individual of type A of the ABO blood group without immunization. Cloning was performed by means of heterohybridoma formation of cell fusion between human peripheral lymphocytes and mouse myeloma cells. The antibody selectively reacted with B-antigen in flow cytometry using red blood cells and enzyme-linked immunosorbent assay. The VH and VL genes of BT97 were derived from the germline genes of DP-47 and 3p.81A4, respectively, with a couple of somatic mutational events. Comparative analysis with other reported anti-A, B and H antibodies revealed that the amino acid sequence of the VH region was more homologous than that of the VL region. The sequence of BT97 showed complete identity with one anti-H natural antibody reported by Marks et al., with the exception of the CDR3 region. It is not known whether the homologies include the common properties of the natural antibodies; however, a particular germline gene potentially changes to anti-ABH antibodies. We think that this method is suitable for cDNA preparation of human monoclonal antibodies to blood group antigens and for sequence analysis.
Kaneko
Mika
M
Department of Forensic Medicine, Yamagata University School of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan.
Kato
Yukinari
Y
Horiuchi
Hidekazu
H
Osawa
Motoki
M
D000017:ABO Blood-Group System / Q000276:immunology*; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry* / Q000276:immunology*; D000918:Antibody Specificity / Q000276:immunology*; D002459:Cell Fusion; D002999:Clone Cells / Q000502:physiology; D022801:Complementarity Determining Regions; D004797:Enzyme-Linked Immunosorbent Assay; D004912:Erythrocytes / Q000276:immunology; D005434:Flow Cytometry; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000737:chemistry / Q000235:genetics; D007147:Immunoglobulin Light Chains / Q000737:chemistry / Q000235:genetics; D007135:Immunoglobulin Variable Region / Q000737:chemistry / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction; D040681:Structural Homology, Protein
D000017:ABO Blood-Group System; D000911:Antibodies, Monoclonal; D022801:Complementarity Determining Regions; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D007135:Immunoglobulin Variable Region