A novel anti-seminoma monoclonal antibody (M2A) labelled with technetium-99m: potential application for radioimmunoscintigraphy.
OBJECTIVE
To study the potential usefulness of monoclonal antibody (mAb) M2A specific for seminoma to image tumour nodules in a preclinical nude mouse model.


METHODS
MAb M2A was labelled with technetium-99m (99mTc) following reduction and was administered intraperitoneally to nude mice bearing subcutaneous HEY cell xenografts against which the antibody was originally raised. Biodistribution and gamma scintigraphy studies were performed 24 h after administration of 99mTc-M2A.


RESULTS
Biodistribution studies showed specific targeting of 99mTc-M2A to HEY tumours in comparison with control mAb 99mTc-6E8 and 99mTc-2G3 which do not bind to HEY cells. Subcutaneous HEY cell tumours (0.5-1.0 g) were successfully imaged using gamma-scintigraphy following administration of 99mTc-M2A.


CONCLUSIONS
The results of this study indicate the potential usefulness of 99mTc-M2A as a clinical reagent for imaging seminoma metastases.
Marks
A
A
Banting and Best Department of Medical Research, University of Toronto, Ontario, Canada.
Ballinger
J R
JR
Reilly
R M
RM
Law
J
J
Baumal
R
R
D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D005260:Female; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D010051:Ovarian Neoplasms; D016719:Radioimmunodetection / Q000379:methods*; D018239:Seminoma / Q000000981:diagnostic imaging* / Q000378:metabolism; D013370:Subrenal Capsule Assay; D013667:Technetium / Q000378:metabolism; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D013667:Technetium