Additionally, KMO−/− mice displayed elevated serum levels of kynurenine, anthranilic acid, and KYNA, along with decreased levels of chemokines such as chemokine ligand (CCL) 1, CCL2, CCL3, and CCL4, suggesting the potential of targeting indoleamine 2,3-dioxygenase or inhibiting KMO to improve myocarditis outcomes. This evidence concerns the gene CCL4 and myocarditis.