Cat No.: 31B100 ★Download Datasheet★
Introduction
Procollagen type III is synthesized in fibroblasts as a biosynthetic precursor of collagen type III, and then released. The propeptides are split off in the extracellular space during the conversion into collagen. The N-terminal propeptide (PIIINP; MW 45KDa) is formed during this process in equimolar proportions to collagen type III and enters the circulation.
Bloodstream levels of PIIINP can therefore be used as a measurement of collagen III synthesis. As the one of biomarkers of the
Enhanced Liver Fibrosis (ELF) score, PIIINP shows good positive correlations with fibrosis stages in chronic liver disease.
Principle of the Assay
This assay is a quantitative sandwich enzyme-linked immunosorbent assay (ELISA). The microtiter plate is pre-coated with a
polyclonal antibody specific for human PIIINP. Standards and samples are pipetted into the wells and any human PIIINP present is
bound by the immobilized antibody. After washing away any unbound substances, a biotin-labeled polyclonal antibody specific for
human PIIINP is added to the wells. After the wash step to remove any unbound reagents, streptavidin-horseradish peroxidase
conjugate (STP-HRP) is added. After the last wash step, an HRP substrate solution is added and color develops in proportion to the
amount of human PIIINP bound initially. The assay is stopped, and the optical density of the wells is determined using a microplate
reader. Since the increases in absorbance are directly proportional to the amount of captured human PIIINP, the unknown sample
concentration can be interpolated from a reference curve included in each assay.
Assay Characteristics
Sensitivity
The lowest level of human PIIINP that can be detected by this assay is 97.5pg/mL.
Precision
Intra-assay Precision (Precision within an assay) C.V.<2.9%.
Inter-assay Precision (Precision between assays) C.V.<6.1%
Publications Citing This Product
1. Kuivaniemi H, et al. (2019). Type III collagen (COL3A1): Gene and protein structure, tissue distribution, and associated diseases.
2. Ralf Lichtinghagen, et al. (2012) The Enhanced Liver Fibrosis (ELF) score: Normal values, influence factors and proposed cut-off
values.