Name
SAP, Human, ELISA kit
Catalog nr
HK331
(lot number and expiry date are indicated on the label)
Short description
Serum amyloid P component (SAP) belongs to a highly conserved superfamily of calcium-dependent ligand binding and lectin (carbohydrate binding) proteins. Due to the pentameric structure these proteins are also called pentraxins. SAP is 25kDa in size. C-reactive protein (CRP) and SAP are well-charactarized short pentraxins, which are produced in the liver in response to inflammatory mediators. Pentraxin 3 (PTX3) is the prototypic long pentraxin. Both SAP and CRP are evolutionary conserved in all vertebrates and found in distant invertebrates such as the horseshoe crab (Limulus polyphemus). They share 51% residue sequence identity and 66% homology....
Size
2 x 96 det.
Application
Manual
Description
Serum amyloid P component (SAP) belongs to a highly conserved superfamily of calcium-dependent ligand binding and lectin (carbohydrate binding) proteins. Due to the pentameric structure these proteins are also called pentraxins. SAP is 25kDa in size. C-reactive protein (CRP) and SAP are well-charactarized short pentraxins, which are produced in the liver in response to inflammatory mediators. Pentraxin 3 (PTX3) is the prototypic long pentraxin. Both SAP and CRP are evolutionary conserved in all vertebrates and found in distant invertebrates such as the horseshoe crab (Limulus polyphemus). They share 51% residue sequence identity and 66% homology.
SAP is highly resistant to proteolysis, especially when it forms complexes with calcium-dependent ligands. SAP avidly binds to macromolecular ligands, such as nucleosomal DNA, glycosaminoglycans and amyloid fibrils. When aggregated it can bind C1q and activate the classical complement pathway.
Human SAP is not an acute phase reactant following acute stimuli, this in contrast to mouse SAP and human CRP. In mouse, SAP levels increase significantly 24 hours after challenge with lipopolysaccharide.
SAP is a normal plasma constituent that is present in cerebrospinal fluid (CSF), in the pathognomonic lesions of Alzheimer's disease (AD), cerebrovascular and intracerebral Aβ amyloid plaques and neurofibrillary tangles. This is a result of its binding to amyloid fibrils and to paired helical filaments, respectively. The protein itself may also be directly neurocytotoxic. SAP contributes significantly to the pathogenesis of amyloidosis. The mechanism of its participation is not yet known and importantly may differ between species.
The normal human serum level of SAP is 30-40 µg/ml. One study described that the mean SAP concentration in serum of women (24 µg/ml) is significantly lower than in men (32 µg/ml). The concentration does not alter significantly after major surgery and is only slightly increased during chronic active diseases. Significantly low levels of SAP are only seen in patients with severe hepatocellular impairment which reduces plasma protein synthesis. In cerebrospinal fluid (CSF), the mean level of SAP in healthy individuals is 8.5 ng/ml.
SAP is highly resistant to proteolysis, especially when it forms complexes with calcium-dependent ligands. SAP avidly binds to macromolecular ligands, such as nucleosomal DNA, glycosaminoglycans and amyloid fibrils. When aggregated it can bind C1q and activate the classical complement pathway.
Human SAP is not an acute phase reactant following acute stimuli, this in contrast to mouse SAP and human CRP. In mouse, SAP levels increase significantly 24 hours after challenge with lipopolysaccharide.
SAP is a normal plasma constituent that is present in cerebrospinal fluid (CSF), in the pathognomonic lesions of Alzheimer's disease (AD), cerebrovascular and intracerebral Aβ amyloid plaques and neurofibrillary tangles. This is a result of its binding to amyloid fibrils and to paired helical filaments, respectively. The protein itself may also be directly neurocytotoxic. SAP contributes significantly to the pathogenesis of amyloidosis. The mechanism of its participation is not yet known and importantly may differ between species.
The normal human serum level of SAP is 30-40 µg/ml. One study described that the mean SAP concentration in serum of women (24 µg/ml) is significantly lower than in men (32 µg/ml). The concentration does not alter significantly after major surgery and is only slightly increased during chronic active diseases. Significantly low levels of SAP are only seen in patients with severe hepatocellular impairment which reduces plasma protein synthesis. In cerebrospinal fluid (CSF), the mean level of SAP in healthy individuals is 8.5 ng/ml.
Cross Reactivity
|
Cross reactant |
Reactivity |
|
Mouse SAP |
negative |
|
Human SAA |
negative |
|
Human PTX3 |
negative |
Species
Human
Features
- Working time of 3½ hours.
- Minimum concentration which can be measured is 0.5 ng/ml.
- Measurable concentration range of 0.2 to 50 ng/ml.
- Working volume of 100 µl/well
Typical standard curve
Principle
The human SAP ELISA is a ready-to-use solid-phase enzyme-linked immunosorbent assay based on the sandwich principle with a working time of 3½ hours.
The efficient format of 2 plates with twelve disposable 8-well strips allows free choice of batch size for the assay.
Samples and standards are incubated in microtiter wells coated with antibodies recognizing human SAP.
Biotinylated tracer antibody will bind to the captured human SAP.
Streptavidin-peroxidase conjugate will bind to the biotinylated tracer antibody.
Streptavidin-peroxidase conjugate will react with the substrate, tetramethylbenzidine (TMB).
The enzyme reaction is stopped by the addition of oxalic acid.
The absorbance at 450 nm is measured with a spectrophotometer. A standard curve is obtained by plotting the absorbance (linear) versus the corresponding concentrations of the human SAP standards (log).
The human SAP concentration of samples, which are run concurrently with the standards, can be determined from the standard curve.
The efficient format of 2 plates with twelve disposable 8-well strips allows free choice of batch size for the assay.
Samples and standards are incubated in microtiter wells coated with antibodies recognizing human SAP.
Biotinylated tracer antibody will bind to the captured human SAP.
Streptavidin-peroxidase conjugate will bind to the biotinylated tracer antibody.
Streptavidin-peroxidase conjugate will react with the substrate, tetramethylbenzidine (TMB).
The enzyme reaction is stopped by the addition of oxalic acid.
The absorbance at 450 nm is measured with a spectrophotometer. A standard curve is obtained by plotting the absorbance (linear) versus the corresponding concentrations of the human SAP standards (log).
The human SAP concentration of samples, which are run concurrently with the standards, can be determined from the standard curve.
Storage and stability
Upon receipt, store individual components at 2 - 8°C. Do not freeze.
Do not use components beyond the expiration date printed on the kit label.
The standard, tracer and streptavidin-peroxidase are stable in lyophilized form until the expiration date indicated on the kit label, if stored at 2 - 8°C.
The exact concentration of the standard is indicated on the label of the vial and the certificate of quality control.
Once reconstituted, standard, tracer and streptavidin-peroxidase are stable for 1 month if stored at 2 - 8°C.
Upon receipt, foil pouch around the plate should be vacuum-sealed and unpunctured. Any irregularities to aforementioned conditions may influence plate performance in the assay.
Return unused strips immediately to the foil pouch containing the desiccant pack and reseal along the entire edge of the zip-seal. Quality guaranteed until expiration date if stored at 2 - 8°C.
Do not use components beyond the expiration date printed on the kit label.
The standard, tracer and streptavidin-peroxidase are stable in lyophilized form until the expiration date indicated on the kit label, if stored at 2 - 8°C.
The exact concentration of the standard is indicated on the label of the vial and the certificate of quality control.
Once reconstituted, standard, tracer and streptavidin-peroxidase are stable for 1 month if stored at 2 - 8°C.
Upon receipt, foil pouch around the plate should be vacuum-sealed and unpunctured. Any irregularities to aforementioned conditions may influence plate performance in the assay.
Return unused strips immediately to the foil pouch containing the desiccant pack and reseal along the entire edge of the zip-seal. Quality guaranteed until expiration date if stored at 2 - 8°C.
Precautions
For research use only, not for diagnostic or therapeutic use.
This kit should only be used by qualified laboratory staff.
Do not add under any circumstances sodium azide as preservative to any of the components.
Do not use kit components beyond the expiration date.
Do not mix reagents from different kits and lots. The reagents have been standardized as a unit for a given lot. Use only the reagents supplied by manufacturer.
The assay has been optimized for the indicated standard range. Do not change the standard range.
Standard, tracer and streptavidin-peroxidase vials should be opened after reconstitution. Open vials carefully: vials are under vacuum.
Do not ingest any of the kit components.
Kit reagents contain 2-chloroacetamide as a preservative. 2-Chloroacetamide is harmful in contact with skin and toxic if swallowed. In case of accident or if you feel unwell, seek medical advise immediately.
The TMB substrate is light sensitive, keep away from bright light. The solution should be colorless until use.
The stop solution contains 2% oxalic acid and can cause irritation or burns to respiratory system, skin and eyes. Direct contact with skin and eyes should be strictly avoided. If contact occurs, rinse immediately with plenty of water and seek medical advise.
Incubation times, incubation temperature and pipetting volumes other than those specified may give erroneous results.
Do not reuse microwells or pour reagents back into their bottles once dispensed.
Handle all biological samples as potentially hazardous and capable of transmitting diseases.
Hemolyzed, hyperlipemic, heat-treated or contaminated samples may give erroneous results.
Use polypropylene tubes for preparation of standard and samples. Do not use polystyrene tubes or sample plates.
The standard is of human origin. It was tested for various viruses and found negative. Since no test method can offer complete assurance that infectious agents are absent, this reagent should be handled as any potentially infectious human serum or blood specimen. Handle all materials in contact with this reagent according to guide-lines for prevention of transmission of blood-borne infections.
This kit should only be used by qualified laboratory staff.
Do not add under any circumstances sodium azide as preservative to any of the components.
Do not use kit components beyond the expiration date.
Do not mix reagents from different kits and lots. The reagents have been standardized as a unit for a given lot. Use only the reagents supplied by manufacturer.
The assay has been optimized for the indicated standard range. Do not change the standard range.
Standard, tracer and streptavidin-peroxidase vials should be opened after reconstitution. Open vials carefully: vials are under vacuum.
Do not ingest any of the kit components.
Kit reagents contain 2-chloroacetamide as a preservative. 2-Chloroacetamide is harmful in contact with skin and toxic if swallowed. In case of accident or if you feel unwell, seek medical advise immediately.
The TMB substrate is light sensitive, keep away from bright light. The solution should be colorless until use.
The stop solution contains 2% oxalic acid and can cause irritation or burns to respiratory system, skin and eyes. Direct contact with skin and eyes should be strictly avoided. If contact occurs, rinse immediately with plenty of water and seek medical advise.
Incubation times, incubation temperature and pipetting volumes other than those specified may give erroneous results.
Do not reuse microwells or pour reagents back into their bottles once dispensed.
Handle all biological samples as potentially hazardous and capable of transmitting diseases.
Hemolyzed, hyperlipemic, heat-treated or contaminated samples may give erroneous results.
Use polypropylene tubes for preparation of standard and samples. Do not use polystyrene tubes or sample plates.
The standard is of human origin. It was tested for various viruses and found negative. Since no test method can offer complete assurance that infectious agents are absent, this reagent should be handled as any potentially infectious human serum or blood specimen. Handle all materials in contact with this reagent according to guide-lines for prevention of transmission of blood-borne infections.
Also available
MSDS
| Related products | Cat # | |
|---|---|---|
| SAA, Human, ELISA kit | HK333 | |
| Pentraxin 3, Human, ELISA kit | HK347 | |