Livers from mice lacking MAIT cells or enriched in MAIT cells exposed to CCl4 did not show differences in the frequency of CD4+ and CD8+ T lymphocytes, B lymphocytes, neutrophils, macrophages, and dendritic cells between the two groups in the different models, demonstrating that the resistance of MR1−/− mice to fibrosis and the exacerbation in Vα19TCRTg were not secondary to changes in other immune cell populations (Supplementary Fig. 5c, d). This evidence concerns the gene CD4 and fibrosis.