The S region of the H-2 complex controls the serum levels of two proteins, Ss and Sip, which are closely related antigenically (1-4). Several observations suggest that the Ss protein may be part of the complement system and homologous to C4. F(ab')2 fragments of antibody to Ss inhibit the hemolytic activity of mouse serum (5) and Ss antigenic determinants are incorporated into immune complexes ...

The short consensus/complement repeat (SCR) domain (also known as the complement control protein domain) is the most abundant domain type in the complement system. Crystal and NMR structures for proteins that contain single and multiple SCR domains have now been published. These contain inter-SCR linkers of between three and eight residues, and the structures show much variability in inter-SCR ...

The mammalian complement system plays an important role in the immune defense in blood and interstitial fluids. This set of ~30, mostly multi-domain, plasma proteins and cell-surface receptors enables the host to recognize and clear invading pathogens and altered host cells, while protecting healthy host cells and tissues. In addition to humoral immune defense, complement proteins are produced ...

The system of plasma proteins called complement was so-named because it complements the activity of antibody in the lysis of bacteria. It has a central role in host defence against many micro-organisms and in the modulation of inflammatory reactions, an activity that has been illuminated by the study of humans with naturally occurring deficiencies of complement. Complement is activated by three...

The complement system is involved not only in host defense against infection but also in autoimmune tissue damage. Using a radioimmunoassay, we sought to measure levels of C3a, C4a and C5a (activated complement fragments with anaphylatoxin functions) in human vitreous humor from eyes with and without vitreal inflammation. Vitreous from 11 patients with clinical evidence of vitritis (Group 2) ha...

objective(s): this study aimed to find the effects of silver nanoparticles (ag-nps) (40 nm) on skin wound healing in mice mus musculus when innate immune system has been suppressed.materials and methods: a group of 50 balb/c mice of about 8 weeks (weighting 24.2±3.0 g) were randomly divided into two groups: ag-nps and control group, each with 25 mice. once a day at the same time, a volume of 50...