Extranodal dissemination of non-Hodgkin lymphoma requires CD47 and is inhibited by anti-CD47 antibody therapy

Blood. 2011 Nov 3;118(18):4890-901. doi: 10.1182/blood-2011-02-338020. Epub 2011 Aug 9.

Abstract

Non-Hodgkin lymphoma (NHL) presents as both localized and disseminated disease with spread to secondary sites carrying a worse prognosis. Although pathways driving NHL dissemination have been identified, there are few therapies capable of inhibiting them. Here, we report a novel role for the immunomodulatory protein CD47 in NHL dissemination, and we demonstrate that therapeutic targeting of CD47 can prevent such spread. We developed 2 in vivo lymphoma metastasis models using Raji cells, a human NHL cell line, and primary cells from a lymphoma patient. CD47 expression was required for Raji cell dissemination to the liver in mouse xenotransplants. Targeting of CD47 with a blocking antibody inhibited Raji cell dissemination to major organs, including the central nervous system, and inhibited hematogenous dissemination of primary lymphoma cells. We hypothesized that anti-CD47 antibody-mediated elimination of circulating tumor cells occurred through phagocytosis, a previously described mechanism for blocking anti-CD47 antibodies. As predicted, inhibition of dissemination by anti-CD47 antibodies was dependent on blockade of phagocyte SIRPα and required macrophage effector cells. These results demonstrate that CD47 is required for NHL dissemination, which can be therapeutically targeted with a blocking anti-CD47 antibody. Ultimately, these findings are potentially applicable to the dissemination and metastasis of other solid tumors.

Publication types

  • Evaluation Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies / therapeutic use*
  • CD47 Antigen / immunology*
  • CD47 Antigen / physiology*
  • Humans
  • Immunization, Passive
  • Lymph Nodes
  • Lymphatic Metastasis
  • Lymphoma, Non-Hodgkin / metabolism
  • Lymphoma, Non-Hodgkin / pathology*
  • Lymphoma, Non-Hodgkin / therapy*
  • Mice
  • Mice, Inbred NOD
  • Mice, Transgenic
  • Neoplasm Metastasis
  • Tumor Cells, Cultured
  • Xenograft Model Antitumor Assays

Substances

  • Antibodies
  • CD47 Antigen