T-cell modulation combined with intratumoral CpG cures lymphoma in a mouse model without the need for chemotherapy

Blood. 2009 Apr 9;113(15):3546-52. doi: 10.1182/blood-2008-07-170274. Epub 2008 Oct 21.

Abstract

We have previously shown that intratumoral injection of CpG oligodeoxynucleotide plus systemic chemotherapy can induce a T-cell immune response against lymphoma and serve as a therapeutic vaccine to cure tumors in a murine model. Here, we demonstrate that antibody-mediated modulation of T cells increases the efficacy of CpG vaccination, thereby eliminating the need for chemotherapy. T-cell modulation was accomplished by targeting both effector and regulatory T-cell populations using systemic administration of monoclonal antibodies against OX40, CTLA4, GITR, and folate receptor 4 (FR4). Each of these antibodies enhanced the effect of intratumoral CpG. Some pairwise combinations of these antibodies potentiated T-cell modulation and further enhanced the efficacy of CpG vaccination. Specifically, the combination of anti-OX40 and anti-CTLA4 which enhance activation and block cell-intrinsic negative regulatory circuits in T cells, respectively, was especially potent. When combined with intratumoral CpG, it induced antitumor CD4 and CD8 T-cell immunity, cured large and systemic lymphoma tumors without chemotherapy, and provided long-lasting immunity against tumor rechallenge. Our results show that the combination of intratumoral CpG and immunomodulatory T-cell antibodies has promise for therapeutic vaccination against lymphoma. These reagents are becoming available for human clinical trials.

Publication types

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

MeSH terms

  • Adjuvants, Immunologic / pharmacology*
  • Animals
  • CD4-Positive T-Lymphocytes / cytology
  • CD8-Positive T-Lymphocytes / cytology
  • Cancer Vaccines / genetics
  • Cancer Vaccines / pharmacology
  • Cell Line, Tumor
  • Combined Modality Therapy
  • Disease Models, Animal
  • Female
  • Genetic Therapy / methods*
  • Immunotherapy / methods*
  • Lymphoma, B-Cell / immunology
  • Lymphoma, B-Cell / therapy*
  • Mice
  • Mice, Inbred BALB C
  • Mice, Knockout
  • Mice, SCID
  • Neoplasm Transplantation
  • Oligodeoxyribonucleotides / pharmacology*
  • T-Lymphocytes, Regulatory / immunology*

Substances

  • Adjuvants, Immunologic
  • CPG-oligonucleotide
  • Cancer Vaccines
  • Oligodeoxyribonucleotides