Dual-targeting immunotherapy of lymphoma: potent cytotoxicity of anti-CD20/CD74 bispecific antibodies in mantle cell and other lymphomas. Academic Article uri icon

Overview

abstract

  • We describe the use of novel bispecific hexavalent Abs (HexAbs) to enhance anticancer immunotherapy. Two bispecific HexAbs [IgG-(Fab)(4) constructed from veltuzumab (anti-CD20 IgG) and milatuzumab (anti-CD74 IgG)] show enhanced cytotoxicity in mantle cell lymphoma (MCL) and other lymphoma/leukemia cell lines, as well as patient tumor samples, without a crosslinking Ab, compared with their parental mAb counterparts, alone or in combination. The bispecific HexAbs have different properties from and are more potent than their parental mAbs in vitro. The juxtaposition of CD20 and CD74 on MCL cells by the HexAbs resulted in homotypic adhesion and triggered intracellular changes that include loss of mitochondrial transmembrane potential, production of reactive oxygen species, rapid and sustained phosphorylation of ERKs and JNK, down-regulation of pAkt and Bcl-xL, actin reorganization, and lysosomal membrane permeabilization, culminating in cell death. They also displayed different potencies in depleting lymphoma cells and normal B cells from whole blood ex vivo and significantly extended the survival of nude mice bearing MCL xenografts in a dose-dependent manner, thus indicating stability and antitumor activity in vivo. Such bispecific HexAbs may constitute a new class of therapeutic agents for improved cancer immunotherapy, as shown here for MCL and other CD20(+)/CD74(+) malignancies.

publication date

  • January 23, 2012

Research

keywords

  • Antibodies, Bispecific
  • Antigens, CD20
  • Antigens, Differentiation, B-Lymphocyte
  • Histocompatibility Antigens Class II
  • Lymphoma, Mantle-Cell

Identity

Scopus Document Identifier

  • 84860332847

Digital Object Identifier (DOI)

  • 10.1182/blood-2011-09-381988

PubMed ID

  • 22271448

Additional Document Info

volume

  • 119

issue

  • 16