Also, a macrophage-specific gene aconitate decarboxylase 1, acod1 (also known as immunoresponsive 1 homolog, irg1), which is known to be highly expressed under bacterial infections and to be important for the production of reactive oxygen species by macrophages [70,71], was among the most induced genes in pneumococcal infection. This evidence concerns the gene ACOD1 and bacterial infectious disease.