Complement fixation

Kompensationsfarbe, /. complementary color. kompensieren, v.t. compensate, komplementar, a. complementary. Komplementarfarbe, /, complementary color. Komplement-bindung, -fixierung, /. complement fixation, -winkel, m. complementary angle. 

Symptoms next include dementia, tremor, and ataxia progressing most often to coma and death survivors show severe chronic meningoencephalitis. The American form of trypanosomiasis (Chagas disease) is a common health problem in Central and Southern America and is transmitted by reduviid bugs. Polymyositis, myocarditis and encephalomyelitis are constant features of the disorder but may be accompanied by more widespread visceral involvement. Infection can be confirmed by complement fixation tests but antibodies do not occur in the blood until about two months after infection. 

The constant regions of the immunoglobulin molecules, particularly the C 2 and 0 3 (and C 4 of IgM and IgE), which constitute the Fc fragment, are responsible for the class-specific effector functions of the different immunoglobulin molecules (Table 50-7, bottom part), eg, complement fixation or transplacental passage. 

Positive history of exposure and use of serology indirect hemagglutination test, ELISA (Chagas EIA, Abbott Labs, Abbott Park, IL), and complement fixation (CF) test. 

Hehre, Genghof and Neill106 c have shown that levans isolated from sucrose cultures of Streptococcus salivarius (and of a spore-forming bacterium) exhibit precipitation and complement fixation when tested against antisera produced by immunization with bacteria obtained from sucrose cultures of either species. 

AIDS, acquired immune deficiency syndrome CF, complement fixation ESR, erythrocyte sedimentation rate HMRT, highly active antiretroviral therapy NSAIDs, nonsteroidal antiinflammatory drugs. 

In most patients, serologic evidence remains the primary method in the diagnosis of histoplasmosis. Results obtained from complement fixation, immunodiffusion, and latex antigen agglutination antibody tests are used... 

Therapy of coccidioidomycosis is difficult, and the results are unpredictable. Only 5% of infected persons require therapy. Candidates for therapy include those with severe primary pulmonary infection or concurrent risk factors (e.g., human immunodeficiency virus infection, organ transplant, or high doses of glucocorticoids), particularly patients with high complement fixation antibody titers in whom dissemination is likely. 

Complement fixation Serum Critical component of humoral immune response leading to lysis of cell membranes, chemotaxis, and phagocytosis... 

IgA has a short half-life in serum (6 days) and comprises about 12-20% of the total serum immunoglobulins. However, because of its presence in bodily fluids, it is the most abundant immunoglobulin present in the body. It comprises three constant domains, and neutrophils, monocytes and some other immune cells possess receptors for IgA (FcaR). Neither of the two IgA subclasses, IgAi and IgA2, can fix complement via the classical pathway. Instead, these antibodies neutralise antigens at mucosal surfaces, in the absence of complement fixation (which would be pro-inflammatory), and the neutralised antigens are cleared. 

Cytotoxicity Cellular Qualitative or semi-quantitative Cell typing Complement fixation tests... 

Apart from antibodies detected by (a) the schizont-infected red cell agglutination test, (b) the agglutination of sporozoites, (c) complement fixation, (d) passive hemagglutination and by the direct and indirect immunofluorescent methods [for review, see reference (V4)], malarial antibodies have also been detected by malarial antigens prepared from heavily infected human placenta, infected human brain, and short-term in vivo cultures of cells from heavily parasitized subjects (Wll) (see Tables 7 and 8). 

A very brief description of biological membrane models, and model membranes, is given. Studies of lateral diffusion in model membranes (phospholipid bilayers) and biological membranes are described, emphasizing magnetic resonance methods. The relationship of the rates of lateral diffusion to lipid phase equilibria is discussed. Experiments are reported in which a membrane-dependent immunochemical reaction, complement fixation, is shown to depend on the rates of diffusion of membrane-bound molecules. It is pointed out that the lateral mobilities and distributions of membrane-bound molecules may be important for cell surface recognition. 

Fig. 11. Evidence that a membrane-associated immunochemical reaction (complement fixation) depends on the mobility of the target hapten (IX) in the plane of a model membrane. The extent of the immunochemical reaction, complement fixation, is measured by A Absorbance at 413 nm. Temperature is always 32°C, which is above the chainmelting temperature (23°C) of dimyristoylphosphatidylcholine used for the data given in A and below the chain-melting transition temperature (42°C) of dipalmitoylphosphatidyl-choline used for the data in B. Thus A refers to a fluid membrane and B refers to a solid membrane. The numbers by each curve are equal to c, the mole % of spin-label hapten IX in the plane of the lipid membrane. It will be seen that complement fixation, as measured by A Absorbance at 413 nm is far more effective in the fluid membrane than in the solid membrane at low hapten concentrations (i.e., c 0.3 mo e%). In C the lipid membrane host is a 50 50 mole ratio mixture of cholesterol and dipalmitoylphosphatidylcholine. The immunochemical data suggest that this membrane is in a state of intermediate fluidity. Specific affinity-purified IgG molecules were used in these experiments. (For further details, see Ref. 5.)... 

Complement fixation assays can be used to look for the presence of specific antibody or antigen in a patient s serum. The test uses sheep red blood cells (SRBC), anti-SRBC antibody and complement, along with specific antigen (if looking for antibody in serum) or specific antibody (if looking for antigen in serum). If antibody... 

FIGURE 6.10 Complement fixation assay. Left Antigen is present in the patient s serum, then the complement is completely utilized and SRBC lysis is minimal. Right Antigen is not present in the patient s serum, then the complement binds anti-SRBC antibody and lysis of the SRBCs ensues. SRBC, sheep red blood cells. 

A sulfated galactolipid, M-6 (607) was isolated from Phyllospongia foliascens. M-6 (607) consisted of an inseparable mixture of compounds with variations occurring in the carboxylic acid portion of the molecule. Compound 607 has resistant activity against complement fixation in serological reactions [484]. 

Jules Bordet Physiology/Medicine Discovery of blood complement complement fixation test... 

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