Preparation of phage antibodies to the ED-A domain of human fibronectin.
The fibronectin (FN) isoform containing the alternative spliced ED-A domain is much more expressed in fetal, tumoral, and regenerating tissues than in normal adult tissues. The ED-A containing FN is up-regulated by numerous cytokines, such as TGF-beta, and, although in normal adult liver the ED-A domain is undetectable, in regenerating rat liver the expression of ED-A is increased and mediates the conversion of fat storing cells to myofibroblasts. Here we describe the selection from a phage display library and the characterization of human antibody fragments directed against the ED-A sequence of FN. As they can be easily radiolabeled with 32P, these antibodies are very highly sensitive reagents for the determination of ED-A levels in tissues and biological fluids; in fact, use of these scFv induced a more than 10-fold increase in sensitivity with respect to the murine monoclonal IST-9. The possibility of preparing a range of human engineered antibodies should facilitate the development of antibody reagents with suitable pharmacokinetics, valency, functional affinity, and effector functions and that could be useful for clinical purposes.
Borsi
L
L
Laboratory of Cell Biology, Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy.
Castellani
P
P
Allemanni
G
G
Neri
D
D
Zardi
L
L
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D001435:Bacteriophages; D005353:Fibronectins / Q000276:immunology*; D005822:Genetic Vectors; D006801:Humans; D007128:Immunoglobulin Fragments / Q000276:immunology; D051379:Mice
D000911:Antibodies, Monoclonal; D005353:Fibronectins; D007128:Immunoglobulin Fragments; C055966:immunoglobulin Fv