Molecule
C5a
Anaphylatoxin and neutrophil chemoattractant
- Expression change
- Generated during activation
- Evidence level
- strong
Role in pathogenesis
C5a is a potent anaphylatoxin generated during complement cascade activation. It recruits neutrophils to vessel walls, driving the leukocytoclastic vasculitis that is the histologic hallmark of HUVS. Also activates mast cells contributing to urticarial manifestations.