...Morten Hedetoft; Martin Bruun Madsen; Cecilie Bo Hansen; Ole Hyldegaard; Peter Garred The hyperinflammatory burden is immense in necrotizing soft-tissue infection (NSTI). The complement system is a key during the innate immune response and may be a promising target to reduce the inflammatory...

...Maisem Laabei; David Ermert The human host has evolved elaborate protection mechanisms to prevent infection from the billions of microorganisms to which it host is exposed and is home. One of these systems, complement, is an evolutionary ancient arm of innate immunity essential for combatting...

...Dani A.C. Heesterbeek; Mathieu L. Angelier; Richard A. Harrison; Suzan H.M. Rooijakkers Complement is a complex protein network of plasma, and an integral part of the innate immune system. Complement activation results in the rapid clearance of bacteria by immune cells, and direct bacterial killing...

... studies have shown that CL-K1 binds to microbes and activates the lectin complement pathway. However, in vivo functions of CL-K1 against microbes have not been elucidated. To investigate the biological functions of CL-K1, we generated CL-K1 knockout (CL-K1 -/- ) mice and then performed a Streptococcus...

...Melanie C. Mühlenkamp; Teresia Hallström; Ingo B. Autenrieth; Erwin Bohn; Dirk Linke; Janina Rinker; Kristian Riesbeck; Birendra Singh; Jack C. Leo; Sven Hammerschmidt; Peter F. Zipfel; Monika S. Schütz Complement resistance is an important virulence trait of Yersinia enterocolitica (Ye...

... phagocytosis and killing by neutrophils. Although the antibodies present in human serum do bind to all fungal morphotypes, we observed no direct antibody-mediated phagocytosis of A. fumigatus . We show that opsonization, phagocytosis and killing by neutrophils of A. fumigatus is complement-dependent. Using...

...Scott R. Barnum Activation of complement leads to generation of the 3 anaphylatoxins C3a, C4a, and C5a. Although all 3 peptides are structurally similar, only C3a and C5a share a similar functional profile that includes the classic inflammatory activities and, more recently, developmental homing...

...Manuel D. Galvan; Holly Hulsebus; Thomas Heitker; Erliang Zeng; Suzanne S. Bohlson The failure to clear apoptotic cells is linked to defects in development and autoimmunity. Complement component C1q is required for efficient engulfment of apoptotic cells (efferocytosis), and C1q deficiency leads...

...Joseph O'Flynn; Karen O. Dixon; Maria C. Faber Krol; Mohamed R. Daha; Cees van Kooten Neutrophils and complement are key members of innate immunity. The alternative pathway (AP) of complement consists of C3, factor B, factor D and properdin, which amplifies AP activation. AP has been implicated...

... surface resulted in degradation of complement factor C3b, and that plasminogen acquisition is associated with a decrease in C3b opsonization and neutrophil-mediated killing in vitro. Furthermore, the ability to acquire cell surface plasmin(ogen) correlates directly with a decrease in C3b opsonization...

...-resistant strains. New treatment strategies are urgently needed, which requires an understanding of disease causation mechanisms. Complement is one of the first lines of defense against bacterial pathogens, and S. aureus expresses several specific complement inhibitors. The effect of extracellular proteases...

... defenses. Complement biochemistry is extensively studied and computational models have been reported previously. However, a critical feature of complement-mediated attack is its spatial dependence: diffusion of mediators into and away from a bacterium is central to understanding C5a generation. Spatial...

... specific elements of the host innate immune system, but their role in bacterial pathogenicity is unknown. For instance, the extracellular complement-binding protein (Ecb) impairs complement activation by binding to the C3d domain of C3. Its homolog, the extracellular fibrinogen-binding protein (Efb...

...Qin Pan; Haidan Chen; Feng Wang; Victor Tunje Jeza; Wei Hou; Yinglan Zhao; Tian Xiang; Ying Zhu; Yuchi Endo; Teizo Fujita; Xiao-Lian Zhang L-ficolin, one of the complement lectins found in human serum, is a novel pattern recognition molecule that can specifically bind to microbial carbohydrates...

... of atherosclerosis are used to study the relevance of candidate factors (cells, genes, diets) in the development and progression of lesions. From a multidisciplinary viewpoint, there are challenges and limitations to this approach. Activation of complement determines or modifies the outcome of acute and chronic...

... classes of the α 2 -macroglobulin family (α 2 M-F) proteins: α 2 -macroglobulin pan-protease inhibitors, C3 complement components, and insect thioester-containing and macroglobulin-related proteins. By using RNA interference-mediated gene silencing in the hard tick Ixodes ricinus we demonstrated...

... and fibrinolysis are almost universally present in septic patients with SIRS. Increasing evidence points to an extensive cross-talk between inflammation and coagulation, in which the protease-activated cell receptors play an important role. Sepsis causes excessive activation of the complement system in which C5a...

... system and function as recognition molecules in the complement system. The 3 human ficolins, ficolin-1 (M-ficolin), ficolin-2 (L-ficolin) and ficolin-3 (H-ficolin or Hakata antigen) are encoded by the FCN1 , FCN2 and FCN3 genes, respectively. Phylogenetic studies suggest that ficolins are of ancient...

... into the Recognition Properties of Human Ficolins Virginie Garlatti Lydie Martin Monique Lacroix Evelyne Gout Gérard J. Arlaud Nicole M. Thielens Christine Gaboriaud Institut de Biologie Structurale JP Ebel, Grenoble, France Key Words Complement Carbohydrate specificity Ficolins Innate immunity Pattern...

... ficolin. Binding of the complex initiates complement activation via the lectin pathway, leading to generation of opsonic fragments of complement components, such as C3b, and to lysis of the bacteria by the membrane attack complex. Thus, serum ficolins play an important role in innate immunity. 16 03...