Re-engineered BCG overexpressing cyclic di-AMP augments trained immunity and exhibits improved efficacy against bladder cancer

Nat Commun. 2022 Feb 15;13(1):878. doi: 10.1038/s41467-022-28509-z.


In addition to its role as a TB vaccine, BCG has been shown to elicit heterologous protection against many other pathogens including viruses through a process termed trained immunity. Despite its potential as a broadly protective vaccine, little has been done to determine if BCG-mediated trained immunity levels can be optimized. Here we re-engineer BCG to express high levels of c-di-AMP, a PAMP recognized by stimulator of interferon genes (STING). We find that BCG overexpressing c-di-AMP elicits more potent signatures of trained immunity including higher pro-inflammatory cytokine responses, greater myeloid cell reprogramming toward inflammatory and activated states, and enhances epigenetic and metabolomic changes. In a model of bladder cancer, we also show that re-engineered BCG induces trained immunity and improved functionality. These results indicate that trained immunity levels and antitumor efficacy may be increased by modifying BCG to express higher levels of key PAMP molecules.

Publication types

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

MeSH terms

  • Animals
  • BCG Vaccine / immunology*
  • CD8-Positive T-Lymphocytes / immunology
  • Cancer Vaccines / immunology*
  • Cell Line, Tumor
  • Cytokines / biosynthesis
  • Cytokines / immunology
  • Dinucleoside Phosphates / biosynthesis
  • Dinucleoside Phosphates / genetics
  • Dinucleoside Phosphates / immunology*
  • Humans
  • Immunity, Innate / immunology
  • Macrophages / immunology
  • Membrane Proteins / metabolism
  • Mice
  • Myeloid Cells / immunology
  • Pathogen-Associated Molecular Pattern Molecules / immunology
  • Rats
  • Urinary Bladder Neoplasms / immunology*
  • Urinary Bladder Neoplasms / therapy*
  • Urothelium / pathology
  • Vaccination


  • BCG Vaccine
  • Cancer Vaccines
  • Cytokines
  • Dinucleoside Phosphates
  • Membrane Proteins
  • Pathogen-Associated Molecular Pattern Molecules
  • STING1 protein, human
  • cyclic diadenosine phosphate