How are natural suture materials broken down in the body?

• A. Phagocytosis
• B. Hydrolysis
• C. Oxidation
• D. Coagulation

Answer: (A)

Natural sutures, such as catgut or other collagen-based threads, are broken down in the body mainly by phagocytic cells. Macrophages (with some contribution from neutrophils) ingest the suture fibers and use proteolytic enzymes, like collagenases, to digest the collagen matrix. The degraded fragments are then cleared by the immune cells, leading to gradual resorption over days to weeks (plain gut tends to absorb faster than chromic gut). This mechanism differs from hydrolysis, which is the primary degradation route for many synthetic absorbable sutures that break down by water-driven cleavage of ester bonds, and it’s not driven by coagulation or oxidation in the context of natural suture breakdown.