NOD2 and Blau syndrome: Blau syndrome is an autosomal dominant granulomatous inflammatory disease caused by mutations in the region encoding for the nucleotide-binding domain region of the NOD2/CARD15 gene (Table 1) [118, 119]: the protein NOD2 is mainly expressed in monocytes and plays a crucial role in the clearance of bacteria, particularly, Mycobacterium tuberculosis, as it is capable of interacting with peptidoglycan and activating the NF-κB signal route [120].