Fractalkine (CX3CL1)- and interleukin-2-enriched neuroblastoma microenvironment induces eradication of metastases mediated by T cells and natural killer cells

Cancer Res. 2007 Mar 1;67(5):2331-8. doi: 10.1158/0008-5472.CAN-06-3041.

Abstract

Fractalkine (FKN) is a unique CX3C chemokine (CX3CL1) known to induce both adhesion and migration of leukocytes mediated by a membrane-bound and a soluble form, respectively. Its function is mediated through CX3C receptor (CX3CR), which is expressed by T(H)1 immune cells including T cells and natural killer (NK) cells. FKN was shown to be expressed in >90% of 68 neuroblastoma samples as determined by cDNA microarray analysis. Here, we characterized the effect of FKN in the neuroblastoma microenvironment using a syngeneic model genetically engineered to secrete FKN. We show FKN-mediated migration, adhesion, and IFN-gamma secretion of immune effector cells, but limited antineuroblastoma activity, in vitro and in vivo. Therefore, we tested the hypothesis that a combined increase of FKN and interleukin-2 (IL-2) in the neuroblastoma microenvironment induces an effective antitumor immune response. For this purpose, IL-2 was targeted to ganglioside GD2, which is highly expressed on neuroblastoma tissue, using an anti-GD2 antibody IL-2 immunocytokine (ch14.18-IL-2). Only mice bearing FKN- and IL-2-enriched neuroblastoma tumors exhibited a reduction in primary tumor growth and a complete eradication of experimental liver metastases. The depletion of T cells and NK cells in vivo abrogated the effect, and these effector cells showed the highest cytolytic activity in vitro. Finally, only the FKN- and IL-2-enriched neuroblastoma microenvironment resulted in T-cell activation and the release of proinflammatory cytokines. In summary, we showed for the first time the immunologic mechanisms by which targeted IL-2 treatment of neuroblastoma with an FKN-rich microenvironment induces an effective antitumor response.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Chemokine CX3CL1
  • Chemokines, CX3C / genetics
  • Chemokines, CX3C / metabolism*
  • Chemokines, CX3C / physiology
  • Female
  • Gene Targeting
  • Humans
  • Immunity, Cellular
  • Immunotherapy / methods
  • Interleukin-2 / genetics
  • Interleukin-2 / therapeutic use*
  • Killer Cells, Natural / immunology*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Membrane Proteins / physiology
  • Mice
  • Mice, Inbred Strains
  • Neoplasm Metastasis
  • Neoplasm Transplantation
  • Neuroblastoma / immunology
  • Neuroblastoma / metabolism
  • Neuroblastoma / pathology*
  • Neuroblastoma / therapy*
  • T-Lymphocytes / immunology*

Substances

  • CX3CL1 protein, human
  • Chemokine CX3CL1
  • Chemokines, CX3C
  • Cx3cl1 protein, mouse
  • Interleukin-2
  • Membrane Proteins