Tumor radioimmunolocalization in nude mice by mono- and divalent- single-chain Fv antiplacental alkaline phosphatase antibodies.
One single-chain Fv antibody fragment (scFv) and a new recombinant covalently linked dimeric scFv antibody (sc(Fv)(2)) against placental alkaline phosphatase (PLAP) were investigated for selective tumor targeting. The biological behavior of these new antibodies was compared to that of the original native antibody, H7 MAb. The sc(Fv)(2)) antibody displayed convincing tumor localization properties with a rapid excretion pattern comparable to the scFv, but with a longer retention time in the tumor, and higher tumor-to-nontumor ratio (27:1), compared to the scFv (15:1), at 48 hours. For the sc(Fv)(2) antibody, more than 50% of the remaining activity in the mouse was present in the tumor between 24 and 48 hours after the injection. With this antibody, scintigraphic visualization of the tumor was also possible 1 week after the injection. It is concluded that this sc(Fv)(2) antibody fragment, with two binding sites, displays properties suitable for in vivo targeting of PLAP expressing tumors.
Sheikholvaezin
Ali
A
Department of Immunology, Umeå University, Umeå, Sweden.
Eriksson
David
D
Ahlström
Katrine Riklund
KR
Johansson
Lennart
L
Stigbrand
Torgny
T
D000469:Alkaline Phosphatase / Q000276:immunology*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology* / Q000494:pharmacology; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009369:Neoplasms / Q000000981:diagnostic imaging* / Q000276:immunology* / Q000473:pathology; D010920:Placenta / Q000276:immunology*; D016719:Radioimmunodetection / Q000379:methods*; D023041:Xenograft Model Antitumor Assays
D000911:Antibodies, Monoclonal; D000469:Alkaline Phosphatase