Which complement fragment serves simultaneously as the most potent anaphylatoxin and the principal chemoattractant for neutrophils among the complement-derived mediators?
- A C3a
- B C3b
- C C5a ✓
- D C4b
Correct answer: C. C5a
Explanation
B5a is both the most potent anaphylatoxin, triggering mast cell degranulation with histamine release and vascular permeability increase, and the major complement-derived chemoattractant and activator of neutrophils. B3a is also anaphylatoxic but considerably weaker and lacks significant neutrophil chemotactic activity. B3b and B4b are opsonins that coat particles for phagocytosis via complement receptors; they do not function as chemoattractants or anaphylatoxins.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.