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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
After binding of complement and antibody on the surface of encapsulated bacteria, the process of phagocytosis by polymorphonuclear leukocytes/macrophages is enhanced by all of the following opsonins, except?
assistant
The correct answer is  The efficiency of phagocytosis is greatly enhanced when microbes are coated with opsonins for which the phagocytes express high-affinity receptors. The major opsonins are immunoglobulin G (IgG) antibodies, the C3b breakdown product of complement, and ceain plasma lectins, notably mannose-binding lectin and collectins, all of which are recognized by specific receptors on leukocytes. CD11b/CD18 (MAC-1) is macrophage integrin which help in binding of microbes to macrophages, and are not opsonins.