Specific imaging of XXXX brain tumor xenografts utilizing radiolabelled monoclonal antibodies (MAbs).

@entity1 @entity5 @entity19 @entity2631 @entity1334 @entity35
At the present time, specific imaging and treatment of central nervous system @entity5 is not possible. The development of monoclonal hybridoma technology may provide the solution to this problem. We have utilized @entity1 glioma-derived cell lines (HGCL) transplanted subcutaneously and intracranially into athymic @entity19 and @entity35 to evaluate the imaging and localizing properties of a panel of MAbs. MAbs 81C6, C12, and D12 and 81C6 @entity1334 have shown significant in vivo localization against HGCL D-54 MG and 81C6 against U-251 MG when compared to equivalent non-specific MAbs. In subcutaneous D-54 MG-induced xenografts, maximal @entity2631 ( @entity2631 ) of up to 15.0 for 81C6, 6.8 for 81C6 @entity1334 , 6.48 for C12, and 4.47 for D12 have been seen. The @entity5 -tissue ratios for normal brain have ranged from 235 for 81C6 to 167 for D12. The total percent injected dose for 81C6 was nearly 5% in U-251 @entity5 and 10% of the initial dose in D-54 @entity5 , while the percent injected dose for control MAb were 1.9% and 2.8%, respectively. Four subcutaneously growing U-251 @entity5 were clearly imaged using 131I-81C6. With intracranially growing D-54 MG, 131I-81C6 provided external imaging of @entity5 at sizes as small as 20 mg while 131I-45.6, a non-specific MAb, provided imaging only when @entity5 achieved sizes greater than 300 mg. These data indicate that operationally specific MAbs and MAb @entity1334 can specifically localize and be used to image @entity1 @entity5 transplanted into immunocompromised animals. The animal models described in this paper provide a sensitive method of evaluating MAbs in pre- @entity1 trials.
