Combined Inhibition of Complement (C5) and CD14 Markedly Attenuates Inflammation, Thrombogenicity, and Hemodynamic Changes in Porcine Sepsis

Abstract

Complement and the TLR family constitute two important branches of innate immunity. We previously showed attenuating effects on inflammation and thromogenicity by inhibiting the TLR coreceptor CD14 in porcine sepsis. In the present study, we explored the effect of the C5 and leukotriene B4 inhibitor Ornithodoros moubata complement inhibitor (OmCI; also known as coversin) alone and combined with anti-CD14 on the early inflammatory, hemostatic, and hemodynamic responses in porcine Escherichia coli–induced sepsis. Pigs were randomly allocated to negative controls (n = 6), positive controls (n = 8), intervention with OmCI (n = 8), or with OmCI and anti-CD14 (n = 8). OmCI ablated C5 activation and formation of the terminal complement complex and significantly decreased leukotriene B4 levels in septic pigs. Granulocyte tissue factor expression, formation of thrombin–antithrombin complexes (p < 0.001), and formation of TNF-α and IL-6 (p < 0.05) were efficiently inhibited by OmCI alone and abolished or strongly attenuated by the combination of OmCI and anti-CD14 (p < 0.001 for all). Additionally, the combined therapy attenuated the formation of plasminogen activator inhibitor-1 (p < 0.05), IL-1β, and IL-8, increased the formation of IL-10, and abolished the expression of wCD11R3 (CD11b) and the fall in neutrophil cell count (p < 0.001 for all). Finally, OmCI combined with anti-CD14 delayed increases in heart rate by 60 min (p < 0.05) and mean pulmonary artery pressure by 30 min (p < 0.01). Ex vivo studies confirmed the additional effect of combining anti-CD14 with OmCI. In conclusion, upstream inhibition of the key innate immunity molecules, C5 and CD14, is a potential broad-acting treatment regimen in sepsis as it efficiently attenuated inflammation and thrombogenicity and delayed hemodynamic changes.

Double Blockade of CD14 and Complement C5 Abolishes the Cytokine Storm and Improves Morbidity and Survival in Polymicrobial Sepsis in Mice

“…We previously demonstrated that coversin is a potent C5 inhibitor in pigs as well as in humans, decreasing E. coli-induced cytokine release in whole blood (54). Furthermore, in a porcine model of E. coli-induced sepsis, coversin attenuated central proinflammatory cytokines such as TNF and IL-6 and efficiently reduced thrombogenicity by reducing the expression of tissue factor (29). The present study demonstrates that coversin led to a significant decrease of almost all tested inflammatory markers.…”

“…In the earlier study using a porcine model of E. coliinduced sepsis, inhibition of C5 and CD14 attenuated inflammation and thrombogenicity and delayed hemodynamic changes (29). In the current study, it is tempting to suggest that the combined inhibition may have had similar effects on thrombogenic and hemodynamic parameters, which may explain the beneficial effect of combined inhibition on survival.…”

“…The consequence of this interplay, which includes redundancy, synergism, and antagonism, suggests inhibiting only complement or TLRs may be insufficient to control inflammation. We have previously demonstrated broad anti-inflammatory effects by simultaneously inhibiting both CD14 and complement (24)(25)(26)(27)(28)(29). In this study, we document the efficacy of C5 and CD14 inhibition on the systemic inflammatory response, morbidity, and survival of mice subject to polymicrobial sepsis.…”

Inhibition of complement C5 protects against organ failure and reduces mortality in a baboon model of Escherichia coli sepsis

“…Well aware that mice are not men (19), translation from rodents to humans has its limitations. Pig models of complement inhibitory therapy in sepsis, in particular in combination with anti-CD14 (20)(21)(22), have yielded promising results. They are more relevant to human pathophysiology than rodent models, but the treatment was limited to only 8 h, as the animals were monitored under full anesthesia.…”

Chimeric Anti-CD14 IGG2/4 Hybrid Antibodies for Therapeutic Intervention in Pig and Human Models of Inflammation

“…[54][55][56], and combined inhibition of CD14 and complement has been suggested as an effective therapeutic approach in conditions associated with detrimental activation of the innate immune system (57,58). We recently showed that combined inhibition on CD14, using the original clone Mil2, and the complement inhibitor OmCI, reduces inflammation, hemostatic disturbances and improved hemodynamics in a porcine model of E. coli sepsis (37). These results were obtained despite the adverse effects seen with the original clone Mil2.…”