Ex vivo induction of multiple myeloma-specific cytotoxic T lymphocytes

Blood. 2003 Aug 15;102(4):1435-42. doi: 10.1182/blood-2002-09-2828. Epub 2003 Apr 24.

Abstract

Multiple myeloma (MM) is an incurable plasma cell malignancy characterized by immunosuppression. In this study, we identified factors in patients' bone marrow (BM) sera inhibiting autologous anti-MM immunity and developed an ex vivo strategy for inducing MM-specific cytotoxic T lymphocytes (CTLs). We found that sera from BM of MM patients inhibited induction of dendritic cells (DCs), evidenced by both phenotype and only weak stimulation of T-cell proliferation. Anti-vascular endothelial growth factor (anti-VEGF) and/or anti-interleukin 6 (anti-IL-6) antibodies neutralized this inhibitory effect, confirming that VEGF and IL-6, at least in part, mediate immunosuppression in MM patients. To induce MM-specific CTLs ex vivo, immature DCs were generated by culture of adherent mononuclear cells in medium containing granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-4 for 5 days and then cocultured with apoptotic MM bodies in the presence of tumor necrosis factor alpha (TNF-alpha) for 3 days to induce their maturation. Autologous BM or peripheral blood mononuclear cells were stimulated weekly with these DCs, and cytotoxicity was examined against the MM cells used to pulse DCs. DCs cultured with apoptotic bodies stimulated significantly greater T-cell proliferation (stimulation index [SI] = 23.2 at a T-DC ratio of 360:1) than T cells stimulated by MM cells only (SI = 5.6), DCs only (SI = 9.3), or MM lysate-pulsed DCs (SI = 13.5). These CTLs from MM patients demonstrated specific cytotoxicity (24.7% at the effector-target [E/T] ratio of 40:1) against autologous primary MM cells. These studies therefore show that CTLs from MM patients can recognize and lyse autologous tumor cells and provide the framework for novel immunotherapy to improve patient outcome in MM.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Apoptosis / immunology
  • Bone Marrow / immunology
  • Cell Division / physiology
  • Cell Line
  • Cytotoxicity, Immunologic
  • Dendritic Cells / cytology
  • Dendritic Cells / drug effects
  • Dendritic Cells / immunology
  • Dendritic Cells / metabolism
  • Endothelial Growth Factors / immunology
  • Endothelial Growth Factors / metabolism
  • Endothelial Growth Factors / pharmacology
  • Granulocyte-Macrophage Colony-Stimulating Factor / pharmacology
  • Humans
  • Intercellular Signaling Peptides and Proteins / immunology
  • Intercellular Signaling Peptides and Proteins / metabolism
  • Intercellular Signaling Peptides and Proteins / pharmacology
  • Interleukin-6 / immunology
  • Interleukin-6 / metabolism
  • Interleukin-6 / pharmacology
  • Lymphocyte Activation / immunology
  • Lymphokines / immunology
  • Lymphokines / metabolism
  • Lymphokines / pharmacology
  • Multiple Myeloma / immunology*
  • Multiple Myeloma / metabolism
  • Phagocytosis
  • Phenotype
  • T-Lymphocytes, Cytotoxic / cytology
  • T-Lymphocytes, Cytotoxic / immunology*
  • Tumor Necrosis Factor-alpha / pharmacology
  • Vascular Endothelial Growth Factor A
  • Vascular Endothelial Growth Factors

Substances

  • Endothelial Growth Factors
  • Intercellular Signaling Peptides and Proteins
  • Interleukin-6
  • Lymphokines
  • Tumor Necrosis Factor-alpha
  • Vascular Endothelial Growth Factor A
  • Vascular Endothelial Growth Factors
  • Granulocyte-Macrophage Colony-Stimulating Factor