Complement system | EPFL Graph Search

The complement system, also known as complement cascade, is a part of the immune system that enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promote inflammation, and attack the pathogen's cell membrane. It is part of the innate immune system, which is not adaptable and does not change during an individual's lifetime. The complement system can, however, be recruited and brought into action by antibodies generated by the adaptive immune system. The complement system consists of a number of small proteins that are synthesized by the liver, and circulate in the blood as inactive precursors. When stimulated by one of several triggers, proteases in the system cleave specific proteins to release cytokines and initiate an amplifying cascade of further cleavages. The end result of this complement activation or complement fixation cascade is stimulation of phagocytes to clear foreign and damaged material, inflammation to attract additional phagocytes, and activation of the cell-killing membrane attack complex. About 50 proteins and protein fragments make up the complement system, including serum proteins, and cell membrane receptors. They account for about 10% of the globulin fraction of blood serum. Three biochemical pathways activate the complement system: the classical complement pathway, the alternative complement pathway, and the lectin pathway. The alternative pathway accounts for the majority of terminal pathway activation and so therapeutic efforts in disease have revolved around its inhibition. In 1888, George Nuttall found that sheep blood serum had mild killing activity against the bacterium that causes anthrax. The killing activity disappeared when he heated the blood. In 1891, Hans Ernst August Buchner, noting the same property of blood in his experiments, named the killing property "alexin", which means "to ward off" in Greek. By 1894, several laboratories had demonstrated that serum from guinea pigs that had recovered from cholera killed the cholera bacterium in vitro.

Clinically compliant cryopreservation of differentiated retinal pigment epithelial cells

Gioele La Manno, Alex Russell Lederer, Cheng Zhao

Background aims: Age-related macular degeneration (AMD) is the most common cause of blindness in elderly patients within developed countries, affecting more than 190 million worldwide. In AMD, the retinal pigment epithelial (RPE) cell layer progressively d ...

Elsevier Sci Ltd2024

A Baseline Cellular Antiviral State Is Maintained by cGAS and Its Most Frequent Naturally Occurring Variant rs610913

Jacques Fellay, Christian Axel Wandall Thorball, Shuting Xu

Upon recognition of aberrantly located DNA, the innate immune sensor cyclic GMP-AMP synthase (cGAS) activates stimulator of IFN genes (STING)/IFN regulatory factor (IRF)3-driven antiviral responses. In this study, we characterized the ability of a specific ...

AMER ASSOC IMMUNOLOGISTS2022

Immune serum-activated human macrophages coordinate with eosinophils to immobilize Ascaris suum larvae

Beatrice Volpe, Julia Esser-von Bieren, Tiffany Babette Angélique Bouchery, Kathleen Shah

Helminth infection represents a major health problem causing approximately 5 million disability-adjusted life years worldwide. Concerns that repeated anti-helminthic treatment may lead to drug resistance render it important that vaccines are developed but ...

WILEY2020