The complement system is part of innate immunity and a link between innate and adaptive immunities. One of the functions of the complement system is tagging foreign pathogens by coating their surfaces with the protein C3b. The complement system discriminates “self” from “nonself” through tight regulation, which involves cleavage of C3b when it coats self-tissues. The membrane cofactor protein (...

Complement factor C3, the central protein of the complement system, was found to be phosphorylated both in EDTA- and heparin-anticoagulated whole blood and in coagulating blood. Complement S protein (vitronectin) was also found to be phosphorylated under these conditions. Further, purified C3 was found to be a phosphoprotein in vivo, containing 0.15 mol of alkali-labile phosphate/mol of protein...

background and objectives: complement proteins are some of the most important plasma proteins of the innate immune system. impaired immune function is reported in subjects who are iron deficient, and there are documents that these patients are prone to infection. this study was conducted to show whether serum c3 and c4 complement change in adult nonpregnant female with iron deficient anemia or ...

Apoptosis is characterized by a lack of inflammatory reaction in surrounding tissues, suggesting local control of complement activation. During the initial stage of apoptosis, cells expose negatively charged phospholipid phosphatidylserine on their surfaces. The vitamin K-dependent protein S has a high affinity for this type of phospholipid. In human plasma, 60-70% of protein S circulates in co...

Protamine sulfate was found to consume large amounts of C selectively during preincubation with sera of individuals in the "acute phase". Marked depletion of C1, C4, and C2 with minimal, if any, depletion of C3-9, was observed. The consumption was time and temperature dependent, occurring most rapidly and extensively at 37 degrees C, 0.10 M relative salt concentration and pH 7.5-8.0; it require...

Complement activation is tightly regulated to avoid excessive inflammatory and immune responses. Crry(-/-) is an embryonic lethal phenotype secondary to the maternal complement alternative pathway (AP) attacking a placenta deficient in this inhibitor. In this study, we demonstrate that Crry(-/-) mice could be rescued on a partial as well as on a complete factor B (fB)- or C3-deficient maternal ...

BACKGROUNDS Cryptococcal meningitis (CM) has been known to lead to significant morbidity and mortality. The relative contribution of the complement system in protection and pathogenesis during CM remains largely unknown. The purpose of this study was to evaluate the baseline complement component profiles in human cerebrospinal fluid (CSF) and plasma from non-HIV patients with CM, and therefore ...

mannose-binding lectin (mbl) is a ca⁺² -dependent collagenous lectin, that is produced by liver and mediates innate immune responses by opsonization of pathogens. the serum level of mbl varies widely among healthy individuals, ranging from 0.05 µg/ml (or lower) to over 5 µg/ml, mainly depending on genetic variation. this study has examined promoter and exon 1 of mbl2 genotype among 117 iranian ...

multiple sclerosis (ms) is a complex, demyelinating disease of the central nervous system (cns) with variable phenotypic presentations, while guillain-barre syndrome (gbs) is the prototypic acute inflammatory disorder that affects the peripheral nervous system. myasthenia gravis (mg) is a t cell dependent and antibody mediated autoimmune disease. although it has been shown that complement plays...