DESCRIPTION

PTPN1 (protein tyrosine phosphatase, non-receptor type 1) is also named as PTP1B or PTP-1B, and belongs to the proteintyrosine phosphatase family and non-receptor class 1 subfamily. PTPN1 is involved in the regulation of several important physiological pathways, which regulates both INS and leptin signaling, and interacts with the epidermal-and platelet-derived growth factor receptors. The gene might harbor variants influencing susceptibility to INS resistance and type 2 diabetes.

PRINCIPLE OF THE ASSAY

Sandwich ELISA structure (Detection antibody labeled with HRP) A capture antibody is pre-coated onto the bottom of wells which binds to analyte of interest. A detection antibody labeled with HRP also binds to the analyte. TMB acts as the HRP substrate and the solution color will change from colorless to blue. A stop solution containing sulfuric acid turns solution yellow. The color intensity is proportional to the quantity of bound protein which is measurable at 450 nm with the correction wavelength set at 630 nm.

PRECISION

Intra-assay Precision (Precision within an assay) Three samples of known concentration were tested 8 times on one plate to assess intra-assay precision. Inter-assay Precision (Precision between assays) Three samples of known concentration were tested in 16 separate assays to assess inter-assay precision.

Intra-assay Precision

Sample	n	Mean (ng/mL)	SD	CV%
1	8	26.71	1.03	3.85
2	8	6.47	0.32	4.93
3	8	3.20	0.07	2.03

Inter-assay Precision

Sample	n	Mean (ng/mL)	SD	CV%
1	16	25.57	1.56	6.10
2	16	6.63	0.31	4.63
3	16	3.34	0.19	5.73

RECOVERY

The recovery of human PTPN1/PTP1B spiked to three different levels throughout the range of the assay in cell lysate was evaluated.

Sample Type		Average% of Expected	Range (%)
Cell lysate	1:32	94	84-105
	1:64	96	94-98

LINEARITY

To assess the linearity of the assay, samples were diluted with the appropriate Sample Diluent to produce samples with values within the dynamic range of the assay. (The cell lysate was initially diluted 1:4.)

		Cell lysate
1:2	Average% of Expected	100
	Range (%)	-
1:4	Average% of Expected	106
	Range (%)	105-107
1:8	Average% of Expected	110
	Range (%)	109-112
1:16	Average% of Expected	117
	Range (%)	115-119

CALIBRATION

This immunoassay is calibrated against a highly purified recombinant human Human PTPN1/PTP1B Sandwich ELISA Kit produced at Sunlong Medical™.