Human Pentraxin 3 Binds to the Complement Regulator C4b-Binding Protein

Human Pentraxin 3 Binds to the Complement Regulator C4b-Binding Protein

The long pentraxin 3 (PTX3) is a soluble recognition molecule with multiple functions including innate immune defense against certain microbes and the clearance of apoptotic cells. PTX3 interacts with recognition molecules of the classical and lectin complement pathways and thus initiates complement activation. In addition, binding of PTX3 to the alternative complement pathway regulator factor ...

Enolase of Streptococcus pneumoniae binds human complement inhibitor C4b-binding protein and contributes to complement evasion.

Streptococcus pneumoniae (pneumococcus) is a pathogen that causes severe local and life-threatening invasive diseases, which are associated with high mortality rates. Pneumococci have evolved several strategies to evade the host immune system, including complement to disseminate and to survive in various host niches. Thus, pneumococci bind complement inhibitors such as C4b-binding protein (C4BP...

Complement Inhibitor C4b-Binding Protein

C4b-binding protein binds to necrotic cells and DNA, limiting DNA release and inhibiting complement activation

After cell death, via apoptosis or necrosis, the uptake of dead cells by neighboring cells or phagocytes prevents the release of intracellular content. An array of molecules, including initiation molecules of the complement system, are involved in marking dead cells for uptake. After binding of these molecules, complement activation takes place, which when uncontrolled might result in a proinfl...

The hyphal and yeast forms of Candida albicans bind the complement regulator C4b-binding protein.

Candida albicans, an important pathogenic yeast, activates all three pathways of the complement system. To understand how this yeast evades the effects of the activated system, we have analyzed the binding of the classical pathway inhibitor C4b-binding protein (C4BP) by C. albicans. Purified native as well as recombinant C4BP bound dose dependently to the yeast and hyphal forms, as shown by mul...