Cytotoxicity of 213Bi- and 225Ac-Immunoconjugates

The paper describes in vitro cytotoxicity experiments with 213-Bi- and 225-Ac-immunoconjugates on the human epidermoid tumour cell line A431 using a blood group A-reactive murine IgG (2D11) as the specific antibody and MOPC 21 as the control antibody. With both radionuclides, specific cell-killing was achieved. The observed cytotoxicity of 213-Bi (T 1/2 = 47 min) indicates that this radionuclide is a useful alternative for the alpha-emitter 212-Bi in the treatment of blood-borne malignancies. 225-Ac-immuno-conjugates may be applicable for the treatment of solid tumours, since the daughter radionuclides of 225-Ca contribute to the cytotoxic efficacy by a field effect (i.e. toxicity in an area distal from antibody-binding site). The lack of an adequate chelator for 225-Ac is a major drawback.

KASPERSEN F.M.;  BOS E.;  DOORNMALEN A.V.;  APOSTOLIDIS Christos; 

1996-08-12

JRC13471