Polarization of Hepatic Macrophages in Alveolar Echinococcosis and Its Role in Remodeling the Immune Microenvironment.

Alveolar echinococcosis (AE), caused by Echinococcus multilocularis larvae, is a severe zoonotic disease mimicking tumors, primarily affecting the liver with high mortality if untreated. Host immunity plays a pivotal role, shifting from Th1/Th17-mediated clearance to Th2/Treg-driven tolerance, enabling parasite survival. Liver macrophages, including Kupffer cells, polarize towards M2 phenotype under parasite antigens (e.g., phytic acid, exosomes), promoting immunosuppression, fibrosis, and T cell exhaustion via IL-10/TGF-β. This reshapes the tumor-like immune microenvironment with M2 macrophages recruiting Tregs, suppressing NK/DC functions, and fostering angiogenesis/fibrosis. Current treatment remains centered on surgery and benzimidazole therapy, both of which have notable limitations. Experimental immunomodulatory strategies, drug repurposing approaches, and targeted delivery systems may offer future therapeutic opportunities, but these concepts remain largely preclinical, unproven in AE, and require careful evaluation for safety and efficacy.