Related Experiment Videos
[Activation of plasma cascade systems in sepsis: role of C1 inhibitors]
S Zeerleder1, C Caliezi, M Redondo
1Hämatologisches Zentrallabor, Universität Bern, Inselspital.
Insights
C1-inhibitor replacement therapy may reduce mortality in severe sepsis and septic shock by inhibiting key inflammatory pathways. This pilot study investigates its efficacy in human patients.
Area of Science:
- Biochemistry
- Immunology
- Pathophysiology
Context:
- Sepsis activates complement, contact activation, and coagulation systems, leading to organ failure and death.
- C1-inhibitor (C1-INH) normally regulates these systems but is inactivated during sepsis.
- Elevated inactivated C1-INH levels correlate with mortality in septic patients.
Purpose:
- To evaluate the efficacy of C1-inhibitor substitution therapy in patients with severe sepsis or septic shock.
- To assess the safety and potential benefits of C1-INH in a human sepsis model.
- To gather data for larger multicenter trials.
Summary:
- This randomized, double-blind, placebo-controlled pilot study administered C1-inhibitor to severe sepsis/septic shock patients.
- C1-INH administration showed potential to attenuate complement and contact activation pathways.
- Observed improvements in hypotension and reduced mortality in animal models informed this human trial.
Impact:
- C1-inhibitor substitution may offer a novel therapeutic strategy for severe sepsis and septic shock.
- Positive results could support larger clinical trials to establish C1-INH as a standard treatment.
- This research may improve outcomes and reduce mortality in critically ill septic patients.
Abstract:
During sepsis the complement system, the contact activation system and the coagulation cascade are activated. Activation of these plasmatic cascades contributes to the development of multiple organ failure and the high mortality rate of severe sepsis and septic shock. C1-inhibitor is the main inhibitor of the classical pathway of the complement system (C1s and C1r), of the contact activation system (factor XIIa and kallikrein) and of the intrinsic pathway of coagulation (factor XIa). During sepsis, C1-inhibitor is proteolytically inactivated. The increase of inactivated C1-inhibitor in plasma correlates positively with mortality in septic patients. C1-inhibitor substitution has been shown to reduce the mortality in experimental animals with severe sepsis or septic shock. Only a few cases of C1-inhibitor substitution in patients with severe sepsis or septic shock have been reported. C1-inhibitor has been shown to attenuate the activation of the complement system and the contact activation system and to improve hypotension. Based on this convincing pathophysiological concept and the results of the animal studies, we initiated the "Bernese C1-inhibitor study", a randomised double-blind and placebo-controlled pilot study involving administration of C1-inhibitor to patients with severe sepsis or septic shock. If the results of this pilot study confirm the results of the reports mentioned above, they will serve as a base for larger multicentre studies.