Preliminary study on immunoscintigraphy of a murine lymphoma using technetium-99m labeled chicken antibody

Aims and background: Radiolabeled antibodies generated against tumor-associ ated antigens are used for immunoscintigraphy to detect tumors and tumor me tastases. Although successful tumor imaging has been achieved using trace-l abeled murine monoclonal antibodies, such antibodies often lead to the deve lopment of human anti-murine antibodies (HAMA), which limit their subsequen t administration for tumor imaging and therapy. It has been reported recent ly that chicken polyclonal antibodies have high affinity and specificity fo r the antigen against which they are raised and do not have any immunologic al cross-reactivity with HAMA. Methods: The present study deals with immunoscintigraphy of Dalton's lympho ma, an experimental tumor model using chicken antibodies generated against Dalton's lymphoma-associated antigen (DLAA) and labeled with technetium-99m (Tc-99m). Results: Scintigrams showed specific uptake of the radiolabel resulting in clear tumor images. The radioactivity uptake of the chicken anti-DLAA antib ody was about twofold higher than that of the non-specific chicken antibody . Conclusions: The results demonstrate the potential of chicken antibody for in vivo radioimmunodetection and localization of tumors.