Opsonization is a crucial immune mechanism where pathogens are coated with opsonins such as antibodies or complement proteins. This coating marks the pathogens for enhanced recognition and ingestion by phagocytic cells like macrophages and neutrophils. By facilitating binding to phagocyte receptors, opsonization significantly increases the efficiency of phagocytosis and clearance of microbes. This process is essential for effective immune defense and resolution of infections.

Reference: Immunology, Janeway et al., 9th Edition.