Cholesterol and pathogens

Cholesterol is an essential component of eukaryotic cell membranes as it affects membrane structural integrity, order, and permeability. Since cholesterol plays an integral role in many cell processes, intracellular pathogens subvert cholesterol at all steps of host cell colonization. Several pathogens target cholesterol-rich microdomains of the plasma membrane to promote their entry, egress, or spread to other cells. Cholesterol is often recruited to pathogen-containing vacuoles to support pathogen replication. Regardless of their intracellular niche, pathogens specifically target cholesterol metabolism, storage, and efflux to acquire cholesterol. Lipoproteins, which are the main cholesterol carriers in the blood, can protect the host against a variety of viruses, bacteria, and parasites. Thus, changes in lipoprotein plasma levels are frequently associated with the increased risk of infectious diseases. As cholesterol triggers inflammatory responses, it can directly affect the immune response against intracellular pathogens. Accordingly, cholesterol-lowering drugs are attractive candidates for host-directed therapy against many infectious diseases.