Role of Hepatic Macrophages in Acute and Chronic Injury and Repair

Abstract

Under optimal physiologic conditions, liver resident macrophages, such as Kupffer cells, are abundant in maintaining homeostasis. They orchestrate postinjury inflammatory tissue remodeling, surveil malignant microbial organisms, and remove toxins. Nevertheless, during chronic inflammation and wound healing in the liver, hepatic infiltration of immune cells from the bone marrow, peritoneum, and lymph nodes can promote the maintenance of macrophages subsets that exacerbate liver injury. Depending on the span of the inflammation and the extent of the damage, the liver can undergo acute liver injury or chronic liver injury. In this review, we explain the role of macrophages in the innate immune system, specifically discussing the role of the immune innate system and the description of Kupffer cells. The review also discusses macrophage activity in acute and chronic liver diseases, such as acetaminophen-induced injury, nonalcoholic steatohepatitis/nonalcoholic fatty liver disease, and alcoholic liver disease. Finally, the review also discuss Kupffer cell mechanisms for liver repair and regeneration.