NEW ANTI-CU-TETA AND ANTI-Y-DOTA MONOCLONAL-ANTIBODIES FOR POTENTIAL USE IN THE PRE-TARGETED DELIVERY OF RADIOPHARMACEUTICALS TO TUMOR

Monoclonal antibodies mere raised against yttrium(III)-1, 4,7, 10-tetr aazacyclododecane-N,N'N '' N'''-tetraacetic acid (Y-DOTA) and copper(I I)-1, 4, 8, 11-tetraazacyclotetradecane-N,N',N '',N'''-tetraacetic aci d (Cu-TETA), Pour hybridomas with high Y-DOTA binding activity and one hybridoma with Cu-TETA activity were selected. MAbs were purified fro m mouse ascites by Protein A affinity chromatography and characterized . Affinity constants were determined by equilibrium dialysis and the h ighest affinity Y-DOTA MAb (K-aff = 1.9 x 10(8) M-1) was further chara cterized by competitive ELISA, Gd-DOTA competed as well as Y-DOTA, whe reas In-DOTA required 740x higher concentrations for 50% inhibition of this Y-DOTA MAb binding to human serum albumin-Y-DOTA-coated microtit er plates, These anti-metal chelate MAbs have potential use as vehicle s for the pretargeted delivery of radiometal chelates to tumors.