C-Reactive Protein ELISA kit

Sample

Salivary

Species Reactivity

Human

Detection Method

sELISA

Intended Use

The Salivary C-Reactive Protein ELISA Kit is an enzyme-linked immunoassay specifically designed and validated for the quantitative measurement of human CRP in oral fluid. It is not intended for diagnostic use. This assay kit was optimized for human salivary research and has not been validated for other human sample types, such as serum or plasma or samples from other species.
Please read the complete kit insert before performing this assay. Failure to follow kit procedure and recommendations for saliva collection and sample handling may result in unreliable values.

Contents of Kit

1. CRP Generation II ELISA Microtitre Break-Apart Plate. Coated with mouse anti-human CRP antibodies. 1/96 well
2. CRP Generation II Standard. 800 pg/mL formulated for stability when stored at 4°C. Prepare and serially dilute before use according to Reagent Preparation. Contains: CRP, buffer, preservative. 1 vial / 1 mL
3. CRP Generation II Controls. High and Low. Contain: CRP, buffer, preservative. 2 vials / 500 μL ea.
4. CRP Generation II Antibody Enzyme Conjugate. Concentrate. Dilute before use with CRP Generation II Assay Diluent. (See Procedure.) Contains: Goat anti-human CRP antibody conjugated to HRP, preservative. 1 vial / 100 μL.
5. CRP Generation II Sample Diluent. Ready to use. Contains: phosphate buffer, preservative. 1 bottle / 25 mL.
6. CRP Generation II Assay Diluent. Contains: phosphate buffer, sodium chloride, protein stabilizer, preservative. 1 bottle / 30 mL
7. Wash Buffer Concentrate 10×. Dilute before use according to Reagent Preparation. Contains: phosphate buffer, detergent, preservative. 1 bottle / 100 mL
8. TMB Substrate Solution. Non-toxic, ready to use. 1 bottle / 25 mL
9. Stop Solution. 1 bottle / 12.5 mL

Storage

All unopened components of this kit are stable at 2-8°C until the kit's expiration date.

Precision

The intra-assay precision was determined from the mean of 20 replicates each.

The inter-assay precision was determined from the mean of average duplicates for 10 separate runs.

General Description

C-Reactive Protein (CRP) circulates in the blood plasma as a stable homopentamer and a prominent member of the acute-phase inflammatory proteins. CRP functions mainly in innate immune defense and levels increase in response to inflammation, infection, tissue damage, necrosis, malignancy and allergic reactions. CRP has diagnostic value as a marker of systemic inflammation in the body and as an independent risk factor for cardiovascular diseases in adults and children.
CRP, also known as pentraxin 1 (PTX1), is a member of the pentraxin family which has several structurally related members. Most CRP is produced by hepatocytes in the liver induced principally by the inflammatory cytokine interleukin-6 (IL-6), but also by IL-1β and TNF.
CRP binds several targets including phosphocholine, a common constituent of polysaccharide coatings of bacterial pathogens and mammalian cell membranes. This allows CRP to function as an opsonin, facilitating phagocytosis of pathogens and dead or dying cells and trigger the classical complement pathway by activating C1q. CRP binding also can stimulate macrophage tumoricidal activity, and protect against septic shock. Another mechanism by which CRP interacts with the innate immune system is through its interaction with Fcγ receptors (FcγRs) on myeloid cells, B lymphocytes, NK cells, and platelets.
Circulating CRP levels in humans are normally quite low, but they increase several hundred fold during the acute-phase response. Elevated serum CRP levels have been associated with the presence of cardiovascular disease. Numerous research studies investigating serum CRP and its relationship to other diseases have also been reported. These include hypertension, diabetes, cancer, autoimmune disorders, obesity and metabolic syndrome. Additional literature suggests possible links between oral health and chronic infection, inflammation, oxidative stress and heart disease. Studies have also linked elevated serum CRP levels to oral contraceptive use.
For CRP there is encouraging research that suggests salivary CRP may be more strongly associated with serum CRP than is true for other inflammatory markers. CRP is prohibitively large to pass from the circulation into the salivary glands by passive diffusion, and it is believed that small amounts of CRP enter whole saliva mainly as a component of the gingival crevicular fluid (GCF) or through salivary glands. Whole saliva is much easier to collect than GCF, which could make saliva the oral fluid of choice for routine assessment of CRP in clinical or field studies.
As with measurements of salivary cytokines, however, the question of local CRP production in the oral cavity must be considered, since it may obscure the relationship between blood and salivary levels and the interpretation of salivary CRP in relation to other analytes of interest. Although the majority of CRP is thought to originate from the liver, CRP and IL-6 mRNAs have been detected in gingival tissue samples from periodontitis patients and CRP gene expression has been correlated with IL-6 expression.
Several studies have examined the relationship between salivary and serum CRP. One study reported a moderate to strong association between CRP measured in saliva and in serum, while a second longitudinal study found that salivary and plasma CRP were moderately associated cross-sectionally and across two years.

Standard Curve

The results shown below are for illustration only and should not be used to calculate results from another assay.

Example: