NOD2 and infection: BCG is known to reduce the overall childhood morbidity caused by infections other than Mtb46, which could be due to the ability of BCG to induce ‘innate memory' by epigenetically altering the phenotype of infected cells to one producing increased inflammatory cytokines, via autophagy and nucleotide-binding oligomerization domain-containing protein 2 (NOD2)-dependent pathways47, 48.