Human Cystatin SN/CST1 ELISA Kit PicoKine®

Cystatin-SN is a protein that in humans is encoded by the CST1 gene. The cystatin superfamily encompasses proteins that contain multiple cystatin-like sequences. Some of the members are active cysteine protease inhibitors, while others have lost or perhaps never acquired this inhibitory activity. There are three inhibitory families in the superfamily, including the type 1 cystatins (stefins), type 2 cystatins and the kininogens. The type 2 cystatin proteins are a class of cysteine proteinase inhibitors found in a variety of human fluids and secretions, where they appear to provide protective functions. The cystatin locus on chromosome 20 contains the majority of the type 2 cystatin genes and pseudogenes. This gene is located in the cystatin locus and encodes a cysteine proteinase inhibitor found in saliva, tears, urine, and seminal fluid.

Lots Lot 1 (pg/ml) Lot 2 (pg/ml) Lot 3 (pg/ml) Lot 4 (pg/ml) Mean (pg/ml) Standard Deviation CV (%) Sample 1 56 49 57 56 54 3.2 5.9% Sample 2 263 286 255 285 272 13.55 4.9% Sample 3 982 921 916 948 941 26.23 2.7% Lots Lot 1 (pg/ml) Lot 2 (pg/ml) Lot 3 (pg/ml) Lot 4 (pg/ml) Mean (pg/ml) Standard Deviation CV (%) Lots Lot 1 (pg/ml) Lot 2 (pg/ml) Lot 3 (pg/ml) Lot 4 (pg/ml) Mean (pg/ml) Standard Deviation CV (%) Sample 1 56 49 57 56 54 3.2 5.9% Sample 1 56 49 57 56 54 3.2 5.9% Sample 2 263 286 255 285 272 13.55 4.9% Sample 2 263 286 255 285 272 13.55 4.9% Sample 3 982 921 916 948 941 26.23 2.7% Sample 3 982 921 916 948 941 26.23 2.7%

Intra-Assay Precision Inter-Assay Precision Sample 1 2 3 1 2 3 n 16 16 16 24 24 24 Mean (pg/ml) 56 263 982 53 244 937 Standard deviation 4.08 12.36 54.01 4.66 15.86 57.15 CV (%) 7.3% 4.7% 5.5% 8.8% 6.5% 6.1% Intra-Assay Precision Inter-Assay Precision Sample 1 2 3 1 2 3 n 16 16 16 24 24 24 Mean (pg/ml) 56 263 982 53 244 937 Standard deviation 4.08 12.36 54.01 4.66 15.86 57.15 CV (%) 7.3% 4.7% 5.5% 8.8% 6.5% 6.1% Intra-Assay Precision Inter-Assay Precision Intra-Assay Precision Inter-Assay Precision Sample 1 2 3 1 2 3 Sample 1 2 3 1 2 3 n 16 16 16 24 24 24 n 16 16 16 24 24 24 Mean (pg/ml) 56 263 982 53 244 937 Mean (pg/ml) 56 263 982 53 244 937 Standard deviation 4.08 12.36 54.01 4.66 15.86 57.15 Standard deviation 4.08 12.36 54.01 4.66 15.86 57.15 CV (%) 7.3% 4.7% 5.5% 8.8% 6.5% 6.1% CV (%) 7.3% 4.7% 5.5% 8.8% 6.5% 6.1%

Human saliva appears to contain several cysteine proteinase inhibitors that are immunologically related to cystatin S but that differ in their specificity due to amino acid sequence differences. Cystatin SN, with a pI of 7.5, is a much better inhibitor of papain and dipeptidyl peptidase I than is cystatin S, although both inhibit ficin equally well.

Description|Quantity Pre-coated 96-well strip microplate|1 Standard|2 vials Biotinylated antibody (100x) |100ul Avidin-Biotin-Peroxidase Complex (100x) |100ul Sample Diluent|30ml Antibody Diluent|12ml Avidin-Biotin-Peroxidase Diluent|12ml Color Developing Reagent (TMB) |10ml Stop Solution|10ml Wash Buffer (25x) |20ml Adhesive plate sealers|4

Store at 4°C for 6 months, at -20°C for 12 months. Avoid multiple freeze-thaw cycles (Ships with gel ice, can store for up to 3 days in room temperature. Freeze upon receiving.)

Concentration (pg/ml) 0 31.2 62.5 125 250 500 1000 2000 O.D. 0.099 0.177 0.24 0.342 0.556 0.924 1.631 2.753 Concentration (pg/ml) 0 31.2 62.5 125 250 500 1000 2000 O.D. 0.099 0.177 0.24 0.342 0.556 0.924 1.631 2.753 Concentration (pg/ml) 0 31.2 62.5 125 250 500 1000 2000 Concentration (pg/ml) 0 31.2 62.5 125 250 500 1000 2000 O.D. 0.099 0.177 0.24 0.342 0.556 0.924 1.631 2.753 O.D. 0.099 0.177 0.24 0.342 0.556 0.924 1.631 2.753

Microplate Reader capable of reading absorbance at 450nm. Incubator. Automated plate washer (optional) . Pipettes and pipette tips capable of precisely dispensing 0.5 μl through 1 ml volumes of aqueous solutions. Multichannel pipettes are recommended for large amount of samples. Deionized or distilled water. 500ml graduated cylinders. Test tubes for dilution.