DESCRIPTION

ENTPD1(Ectonucleoside triphosphate diphosphohydrolase 1), also known as CD39 or NTPDase 1, is a cell surface enzyme that plays a crucial role in regulating extracellular nucleotide levels and immune responses. ENTPD1 is highly expressed on regulatory T cells (Tregs), where it contributes to their suppressive functions by depleting extracellular ATP and generating adenosine. It is a noncovalent tetrameric protein, and detergent inhibition of enzymatic activity is caused by dissociation of ectoapyrase tetramers into monomers. Moreover, ENTPD1 is involved in the regulation of dendritic cell function and T cell activation. It modulates the local concentration of nucleotides and nucleosides, which in turn affects immune cell signaling and activation.

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	625.1	14.9	2.4
2	8	154.1	2.7	1.7
3	8	74.8	2.4	3.2

Inter-assay Precision

Sample	n	Mean (pg/mL)	SD	CV%
1	16	603.4	25.6	4.2
2	16	156.6	3.7	2.4
3	16	76.6	3.5	4.6

RECOVERY

The recovery of human CD39/ENTPD1 spiked to three different levels throughout the range of the assay in human serum was evaluated.

Sample Type		Average% of Expected	Range (%)
Human serum	1:4	94	86-108
	1:8	87	81-92

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.

		Human serum
1:2	Average% of Expected	100
	Range (%)	-
1:4	Average% of Expected	116
	Range (%)	114-117
1:8	Average% of Expected	98
	Range (%)	94-102
1:16	Average% of Expected	97
	Range (%)	96-98

CALIBRATION

This immunoassay is calibrated against a highly purified recombinant human Human CD39/ENTPD1 Sandwich ELISA Kit produced at Sunlong Medical™.

Ordering & shipping

• Minimum order: 1 kit
• Lead time: varies with order quantity and specifications. Please consult your local distributor or our sales team for confirmation
• Payment: T/T 100% in advance; PayPal; Alibaba Trade Assurance
• Shipping: FedEx / DHL / UPS express; cold-chain packing available on request
• Price: USD, per kit (48T / 96T options available)