Havcr2 haploinsufficiency further enhanced macrophage M1 polarization in 2-week MCD-fed mice, leading to liver injury, and attenuated macrophage M2 polarization in 5-week MCD-fed mice, protecting the liver from NASH fibrosis (Fig. S3E). Here, HAVCR2 is linked to metabolic dysfunction-associated steatohepatitis.