Complement Factor B ELISA kit [Human]-2 x 96 det. (CAT#: CB-P071-K) Datasheet

Product Type
Complement is the main defense system of innate immunity, designed to eliminate microorganisms. There are three ways to activate complement. The classical and lectin pathways are initiated by recognizing the binding of proteins to specific targets. IgM, the isotype of IgG, and several other proteins (such as C-reactive protein and serum amyloid P) activate the classical pathway. The lectin pathway begins by the binding of mannose-binding lectins to the carbohydrate moiety mainly found on the surface of pathogens. In contrast to the other two pathways, this alternative pathway is continuously activated due to the spontaneous hydrolysis of complement component C3. Due to this spontaneous activation ability, alternative pathways require continuous adjustment. Endogenous cells and tissues protect themselves from uncontrolled activation by expressing complement regulatory proteins (especially factor H) that can control the activation of alternative pathways. "Activated" surfaces are, to a large extent, surfaces that do not have enough regulatory protein functions to control the activation of alternative pathways (such as pathogen surfaces). The automatic activation process starts with the spontaneous hydrolysis of C3, which leads to the formation of C3 (H2O). In turn, C3 (H2O) binds to complement factor B. After factor B is combined with C3 (H2O), factor B itself will change its conformation, and then it can be cleaved by constitutively active serum protease factor D to produce Ba and Bb. The Bb fragment remains bound to the complex, and can then cleave other C3 molecules through its own serine protease domain to generate a form called C3b. Once C3b is produced, it binds to factor B to generate more C3-convertase, which activates the complement cascade. Factor B circulates in the blood as a single-chain polypeptide. The human factor B ELISA will be used to quantify factor B in plasma samples.
The human factor B ELISA kit is used for in vitro quantitative determination of factor B in plasma and serum samples. This kit is for laboratory research only and cannot be used for diagnostic or therapeutic procedures.
The Human factor B ELISA kit is a ready-made solid-phase enzyme-linked immunosorbent assay based on the sandwich principle. The working time is 3.5 hours. The effective form of the plate with twelve disposable 8-well plates allows free choice of batch size for determination. The samples and standards are incubated in microtiter wells coated with antibodies that recognize human factor B. The biotinylated tracer antibody will bind to the captured human factor B. The streptavidin-peroxidase conjugate will bind to the biotinylated tracer antibody. The streptavidin-peroxidase conjugate will react with the substrate tetramethylbenzidine (TMB). The enzyme reaction is stopped by adding oxalic acid. Measure the absorbance at 450nm with a spectrophotometer. Draw a standard curve by plotting the absorbance (linear) relative to the corresponding concentration (logarithm) of the human factor B standard.  The concentration of human factor B in the sample run at the same time as the standard can be determined from the standard curve.
2 x 96 det.
Detection Method
Enzyme immunoassay (ELISA) technique
Detection Limit
7.8 to 500 ng/ml
7.8 ng/ml
Serum, plasma, tissue homogenates, cell lysates, cell culture supernates and other biological fluids
Specimen Collection
Blood samples were collected using sterile venipuncture techniques, and serum was obtained using standard procedures. At least 5 ml of whole blood is recommended. Let the blood clot in the serum test tube for 60-65 minutes at room temperature (20-25°C). Centrifuge the blood sample and transfer the cell-free serum to a clean test tube. The serum must be handled correctly to prevent complement activation in vitro. Serum should be frozen in a sealed tube at -70°C or lower for long-term storage or transport on dry ice. The sample should not be frozen and thawed more than once. Do not use jaundice, lipemia and hemolytic serum. You cannot use heat-inactivated serum. Plasma cannot be used.
Sample Volume
100 µl/well
Species Reactivity
Cross Reactivity
Horse - No, Mouse - No, Pig - No, Rat - No
Protocol Length
2 hours
Product should be stored at 4 °C. Under recommended storage conditions, product is stable for at least six months.
Research Use
For research use only. Not for use in or on humans or animals or for diagnostics. It is the responsibility of the user to comply with all local/state and Federal rules in the use of this product. Hycult Biotech is not responsible for any patent infringements that might result with the use of or derivation of this product.

All products and services are for Research Use Only. Do Not use in humans.


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