gamma-irradiated bacillus calmette-guérin vaccine

Gamma-irradiated Bacillus Calmette-Guérin (BCG) is an experimental inactivated bacterial vaccine developed by Radboud University Medical Center. Unlike the standard live-attenuated BCG vaccine, this version is killed using gamma irradiation, which preserves the structural integrity of the bacterial cell wall while eliminating the risk of disseminated infection, making it a potentially safer alternative for immunocompromised individuals. The vaccine is designed to induce 'trained immunity'—a form of innate immune memory characterized by epigenetic reprogramming (specifically histone methylation) and metabolic changes in myeloid cells. This training aims to provide non-specific, heterologous protection against a broad range of infections. Mechanistically, the vaccine acts as an agonist of the NOD2 (Nucleotide-binding oligomerization domain-containing protein 2) receptor pathway. Clinical studies have explored its potential to prevent infections and treat sepsis-induced immunoparalysis, although results suggest its effects on the innate immune response are weaker than those of live BCG.

Other names

gamma-irradiated BCGγ-irradiated BCGkilled BCG vaccine