complement deficiency

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complement deficiency

A state in which any of the complement proteins is subnormal
Complement deficiencies–associated disorders
C1r    SLE, renal disease, repeated infections
C1s    SLE
C2    SLE, vasculitis, membranoproliferative glomerulonephritis, dermatomyositis
C3 Repeated infections
C5 SLE, gonococcal disease
C6 Relapsing meningococcal meningitis, gonococcal infection
C7 Raynaud's disease, chronic renal disease, gonococcal infection
C8 SLE, gonococcal infection


a complex series of enzymatic proteins occurring in normal serum that are triggered in a cascade manner by, and combine with, the antibody-antigen complexes, producing lysis when the antigen is an intact cell. Complement comprises 25 to 30 discrete proteins, labeled numerically as C1 to C9, and by letters, i.e. B, D, P, etc., and with C1 being divided into subcomponents C1q, C1r and C1s. Components C3 and C5 are involved in the generation of anaphylatoxin and in the promotion of leukocyte chemotaxis, the result of these two activities being the inflammatory response. C1 and C4 are involved in the neutralization of viruses. The components also combine in various sequences to participate in other biological activities, including antibody-mediated immune lysis, phagocytosis, opsonization and anaphylaxis. The complement system is known to be activated by the immunoglobulins IgM and IgG.

alternate complement pathway, alternative complement pathway
the sequence in which complement components C3 and C5 to C9 are activated without participation by C1, C2 and C4 or the presence of an antibody-antigen complex.
complement cascade
the sequence of reactions, each being the catalyst for the next, that leads to the terminal complement pathway and cell lysis. There are two pathways for activation of C3, the 'classical' (below) and the 'alternate' (above).
classical complement pathway
the one in which all of the complement components C1 to C9 participate and is triggered by antibody-antigen complexes.
complement deficiency
various complement components may be deficient without serious effects on the host. C3 deficiency is most severe and occurs in humans, Brittany spaniels and Finnish-Landrace lambs. Increased susceptibility to infections results.
complement fixation tests
utilize antibody-antigen reaction and result in hemolysis to determine the presence of various organisms in the blood. Involves two stages. In the first, also referred to as the test system, antigen is mixed usually with serial dilutions of a test serum in the presence of complement. If the serum contains antibody, i.e. is positive, an antibody-antigen complex is formed which also binds (fixes) complement. In the second stage, also called the indicator system, sheep red blood cells coated with specific, usually rabbit anti-sheep red blood cell antibody are added. The red blood cells are said to be sensitized. If antibody was not present in stage 1, then the free complement lyses the sensitized sheep red blood cells. The basis of many serological tests including those for glanders, tuberculosis and contagious bovine pleuropneumonia. Called also Bordet-Gengou phenomenon. See also immunity.
complement regulatory proteins
a set of at least seven proteins that are present in plasma (C1 INH, C4b-binding protein, factor H and factor I) or present in cell membranes (decay-accelerating factor [DAF], membrane cofactor protein [MCP] and homologous restriction factor [HHF]) that modulate the complement proteins and protect 'innocent' bystander cells and tissues from complement damage.
terminal complement pathway
the final stages of complement activation in which C5, C6, C7, C8 and C9 are activated; common to both the alternate and classical pathways.
References in periodicals archive ?
In fact, the intensity of C1 increased from about 30.
THE Citroen C1 has always been a car with a winning precept.
Figure 7 shows the temperature profile of the tensile stress and the related relaxation spectrum of an S-SBR vulcanizate of the C1 Sa compound.
PSA's partnership with Toyota actually spawned the Citroen C1, together with the Peugeot 107 and the Toyota Aygo.
A 28-year-old female with previously diagnosed C1 esterase inhibitor deficiency was referred to our hospital for removal of wisdom teeth.
The type (2) then the word before the case point of view, if there is more the kind of string S, then the word before, and then each word before the closer the number of occurrences when, C1S the higher the value, on the contrary, when the character string before the first pick only one word, C1S value equal to 0, or a word of the opportunities before then compared with other large very long time, the C1S value close to 0, indicating that the string plus the first pick the word may is a word.
I DROVE Citroen's new C1 this week - and I thought it was an absolute diamond.
Unsurprisingly the last ten Scoop6s that took place on Grand National day were C1s and probably the hardest-ever Scoop6 to win was when Mon Mome won the Grand National at 100-1 in 2009 - a successful acca on the Scoop6 race winners returned a profit of pounds 39,405,149 to a single unit.
In 2011 the operator Seplat (M&P 45%) will prioritise and direct its efforts to maximise production of P1+P2 reserves by implementing the necessary works to transfer C1s to P1s and C2s to P1 and P2.
AqE] sample was performed on an octadecyl column (EC250/4 NUCLEOSIL 1005 C1S AB; 5[micro]m; 4 mm x 250 mm, MACHEREY-NAGEL, Germany) at ambient temperature, eluted with a linear gradient of acetonitrile (AcCN)/water (0.
In 2011, the new model will be sold throughout China, and SEM aims to sell 50,000 C1s in the new year.