Comparative localization of murine monoclonal antibody Me1-14 F(ab')2 fragment and whole IgG2a in human glioma xenografts.


Journal Article

Monoclonal antibodies (MAbs) targeted to glioma-associated antigens may allow the selective delivery of imaging and therapeutic agents to brain tumors; the use of MAb fragments may be a strategy to further improve tumor uptake of such agents relative to normal tissues. In this study, we have examined the in vivo localization of radioiodinated MAb Me1-14, a murine immunoglobulin G2a (IgG2a) reactive with gliomas, and its F(ab')2 fragment in s.c. and intracranial xenografts of human glioma cell line D-54 MG in athymic mice. The radiolabeled F(ab')2 fragment of Me1-14 was demonstrated to possess in vitro binding affinity and immunoreactivity comparable to that of whole IgG. Direct comparison of IgG and F(ab')2 biodistribution in s.c. xenograft-bearing mice showed higher tumor: normal tissue ratios of the F(ab')2 fragment compared to IgG. In intracranial tumor-bearing mice paired-label analysis using a nonspecific protein control showed earlier specific tumor localization by the F(ab')2 fragment of Me1-14 compared to IgG. Blood-to-tumor transfer constants (K1) derived for Me1-14 F(ab')2 were significantly greater than those for whole Me1-14 (P = 0.01). Estimated radiation dosimetry revealed that 131I-labeled Me1-14 F(ab')2 would deliver higher radiation doses to tumor than to normal tissues. These studies demonstrate that the F(ab')2 fragment of Me1-14 may be a potential agent for immune-directed brain tumor diagnosis and therapy.

Full Text

Duke Authors

Cited Authors

  • Colapinto, EV; Humphrey, PA; Zalutsky, MR; Groothuis, DR; Friedman, HS; de Tribolet, N; Carrel, S; Bigner, DD

Published Date

  • October 15, 1988

Published In

Volume / Issue

  • 48 / 20

Start / End Page

  • 5701 - 5707

PubMed ID

  • 3167830

Pubmed Central ID

  • 3167830

International Standard Serial Number (ISSN)

  • 0008-5472


  • eng

Conference Location

  • United States