Controlling the anaphylatoxin C5a in diseases requires a specifically targeted inhibition.

The terminal complement split product C5a has been described as an important mediator in inflammatory diseases. C5a is generated upon cleavage of C5 and earlier research suggests that, besides the known C5 convertases formed upon activation of the complement pathways, various enzymes could activate C5 directly. We demonstrate that eculizumab effectively blocks C5 activation when mediated by C5-convertase formation, but fails to block C5a generation resulting from direct enzymatic cleavage by trypsin and thrombin.

Treatment with anti-C5a antibody improves the outcome of H7N9 virus infection in African green monkeys.

Background: Patients infected with influenza A(H7N9) virus present with acute lung injury (ALI) that is due to severe pneumonia and systemic inflammation. It is often fatal because there are few effective treatment options. Complement activation has been implicated in the pathogenesis of virus-induced lung injury; therefore, we investigated the effect of targeted complement inhibition on ALI induced by H7N9 virus infection.

Early intra-articular complement activation in ankle fractures.

Cytokine regulation possibly influences long term outcome following ankle fractures, but little is known about synovial fracture biochemistry. Eight patients with an ankle dislocation fracture were included in a prospective case series and matched with patients suffering from grade 2 osteochondritis dissecans (OCD) of the ankle. All fractures needed external fixation during which joint effusions were collected.