DESCRIPTION

SREBF2,also named as BHLHD2, is a 1141 amino acid protein, which contains 1 bHLH domain and belongs to the SREBP family. SREBF2 localizes in the endoplasmic reticulum membrane and is ubiquitously expressed in adult and fetal tissues. SREBF2 as a transcriptional activator is required for lipid homeostasis. SREBF2 expression is dynamically regulated in response to nutritional and hormonal cues. SREBF2 exists two isoform with molecular weight 124 kDa and 73 kDa.

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 (pg/mL )	SD	CV%
1	8	1,196.6	84.1	7.0
2	8	284.5	30.8	10.8
3	8	136.3	14.5	10.7

Inter-assay Precision

Sample	n	Mean (pg/mL )	SD	CV%
1	16	1,209.7	70.8	5.9
2	16	293.2	23.1	7.9
3	16	142.5	12.1	8.5

RECOVERY

The recovery of human SREBF2 spiked to three different levels throughout the range of the assay in cell lysate was evaluated.

Sample Type		Average% of Expected	Range (%)
Cell lysate	1:16	81	78-83

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.

		Cell lysate
1:2	Average% of Expected	100
	Range (%)	-
1:4	Average% of Expected	94
	Range (%)	89-100
1:8	Average% of Expected	101
	Range (%)	92-109
1:16	Average% of Expected	106
	Range (%)	98-115

CALIBRATION

This immunoassay is calibrated against a highly purified recombinant human Human SREBF2 Sandwich ELISA Kit produced at Sunlong Medical™.