Tumor membrane-based vaccine immunotherapy in combination with anti-CTLA-4 antibody confers protection against immune checkpoint resistant murine triple-negative breast cancer

Hum Vaccin Immunother. 2020 Dec 1;16(12):3184-3193. doi: 10.1080/21645515.2020.1754691. Epub 2020 Jun 12.


Triple-negative breast cancer (TNBC) afflicts women at a younger age than other breast cancers and is associated with a worse clinical outcome. This poor clinical outcome is attributed to a lack of defined targets and patient-to-patient heterogeneity in target antigens and immune responses. To address such heterogeneity, we tested the efficacy of a personalized vaccination approach for the treatment of TNBC using the 4T1 murine TNBC model. We isolated tumor membrane vesicles (TMVs) from homogenized 4T1 tumor tissue and incorporated glycosyl phosphatidylinositol (GPI)-anchored forms of the immunostimulatory B7-1 (CD80) and IL-12 molecules onto these TMVs to make a TMV vaccine. Tumor-bearing mice were then administered with the TMV vaccine either alone or in combination with immune checkpoint inhibitors. We show that TMV-based vaccine immunotherapy in combination with anti-CTLA-4 mAb treatment upregulated immunomodulatory cytokines in the plasma, significantly improved survival, and reduced pulmonary metastasis in mice compared to either therapy alone. The depletion of CD8+ T cells, but not CD4+ T cells, resulted in the loss of efficacy. This suggests that the vaccine acts via tumor-specific CD8+ T cell immunity. These results suggest TMV vaccine immunotherapy as a potential enhancer of immune checkpoint inhibitor therapies for metastatic triple-negative breast cancer.

Keywords: CD80; CTLA-4; Cancer vaccine; IL-12; glycosyl phosphatidylinositol anchor; immunotherapy; protein transfer; tumor membrane vesicles.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • CD8-Positive T-Lymphocytes / immunology
  • CTLA-4 Antigen
  • Cancer Vaccines*
  • Cell Line, Tumor
  • Humans
  • Immunotherapy
  • Interleukin-12
  • Mice
  • Triple Negative Breast Neoplasms* / therapy


  • CTLA-4 Antigen
  • Cancer Vaccines
  • Interleukin-12