Single-chain Fv fragment lacks carrier specificity of the native antibody.
A single-chain antibody fragment (scFv) was constructed from a hybridoma antibody that binds to phosphorylcholine (PC) only when this hapten is presented in the form of the immunizing antigen (derived from Trichinella) but not when it is presented on other carriers (as found, for example, in pneumococcal capsules). The scFv derivative was found to lack this carrier specificity as it bound indiscriminately, but specifically, to the various PC-associated antigens, and exhibits a two-fold lower affinity (3.5x10(5)M(-1)) for nitrophenyl-PC than the native antibody. The findings suggest that the scFv combining site is different in fine structure from that of the native antibody.
Poon
Kwok-Man
KM
Clinical Immunology Unit, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, Shatin, China.
Tam
Frankie Chi-Hang
FC
Chui
Yiu-Loon
YL
Lim
Pak-Leong
PL
D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D001666:Binding Sites, Antibody; D006801:Humans; D007128:Immunoglobulin Fragments / Q000737:chemistry / Q000276:immunology*; D019151:Peptide Library; D010767:Phosphorylcholine / Q000276:immunology
D000911:Antibodies, Monoclonal; D007128:Immunoglobulin Fragments; D019151:Peptide Library; C055966:immunoglobulin Fv; D010767:Phosphorylcholine