Granulin, also known as Proepithelin (GRN) is a protein that in humans is encoded by the GRN gene. This gene is mapped to 17q21.31. Granulins are a family of secreted, glycosylated peptides that are cleaved from a single precursor protein with 7.5 repeats of a highly conserved 12-cysteine granulin/epithelin motif. The 88kD precursor protein, progranulin, is also called proepithelin and PC cell-derived growth factor. Cleavage of the signal peptide produces mature granulin which can be further cleaved into a variety of active, 6kD peptides. These smaller cleavage products are named granulin A, granulin B, granulin C, etc. Epithelins 1 and 2 are synonymous with granulins A and B, respectively. Both the peptides and intact granulin protein regulate cell growth. However, different members of the granulin protein family may act as inhibitors, stimulators, or have dual actions on cell growth. Granulin family members are important in normal development, wound healing, and tumorigenesis.
The Progranulin BioAssay™ ELISA Kit is a Sandwich High Sensitivity ELISA for quantitative detection of human GRN n in cell culture supernates, serum, plasma (heparin, EDTA), saliva, urine and human milk.
Detection Range:1562.5-100,000pg/ml
Sensitivity:<50pg/ml
Specificity:Recognizes natural and recombinant human GRN. There is no detectable cross-reactivity with other relevant proteins.
Test Principle:This GRN BioAssay™ ELISA Kit is a Sandwich High Sensitivity ELISA is a solid phase immunoassay specially designed to measure human GRN with a 96-well strip plate that is pre-coated with antibody specific for GRN. The capture antibody is a mooclonal antibody from mouse and the detection antibody is a polyclonal antibody conjugated to biotin from goat. The kit contains recombinant human GRN with immunogen: Expression system for standard: NS0; Immunogen sequence: T18-L593.
To measure human GRN, add standards and samples to the wells, then add the biotinylated detection antibody. Wash the wells with PBS buffer, and add Avidin-Biotin-Peroxidase Complex (ABC-HRP). Wash away the unbounded ABC-HRP with PBS buffer and add TMB. TMB is substrate to HRP and will be catalyzed to produce a blue color product, which changes into yellow after adding acidic stop solution. The density of the yellow product is linearly proportional to human GRN in the sample. Read the density of the yellow product in each well using a plate reader, and benchmark the sample wells' readings against the standard curve to determine the concentration of human GRN in the sample.
Storage and Stability:Store *144014B powder at 4°C. Once reconstituted store at 4°C for up to 12 hours or at -20°C for up to 48 hours. Store other components at 4°C. Stable for 6 months after receipt. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
Assay Summary:1. Add 100ul of samples and standards and incubate the plate at 37°C for 90 minutes or at RT for 2 hours. Do not wash
2. Add 100ul biotinylated antibody and incubate the plate at 37°C for 60 minutes or at RT for 90 minutes. Wash plate 3 times with 0.01M PBS buffer
3. Add 100ul of ABC working solution and incubate the plate at 37°C for 30 minutes or at RT for 40 minutes. Wash plate 5 times with 0.01M PBS buffer
4. Add 90ul of TMB color developing agent and incubate the plate at 37°C in dark for 15-25 minutes or at RT for 30 minutes
