| CPA3

Carboxypeptidase A3 (mast cell carboxypeptidase A), also known as CPA3, is an enzyme encoded by the CPA3 gene. CPA3 shares significant homology with the CPA subfamily of metalloprecarboxypeptidases and all the residues essential for the coordination of the Zn2+ active site, substrate peptide anchoring, and CP activity are preserved in the putative CPA3 protein. It resembles pancreatic CPA1 in cleaving C-terminal aromatic and aliphatic amino acid residues. CPA3 contains an N-terminal sequence of 16 amino acids and a pro-peptide between the NH2-terminal signal peptide sequence and COOH-terminal CP moiety.
 

| Typical data

As the OD values of the standard curve may vary according to the conditions of the actual assay performance (e.g. operator, pipetting technique, wash technique or temperature effects), the operator should establish a standard curve for each test. Typical standard curve and data are provided below for reference only.

 

Concentration (pg/mL)	500	250	125	62.5	31.2	15.6	7.8	0
OD	2.26	1.49	1.03	0.7	0.46	0.32	0.23	0.08
Corrected OD	2.18	1.41	0.95	0.62	0.38	0.24	0.15	-

 

| Repeatability

Intra-assay Precision (Precision within an assay)：CV% < 10%; Inter-assay Precision (Precision between assays)：CV% < 10%
 

| Recovery

The recovery of Human CPA3 spiked at three different levels in samples throughout the range of the assay was evaluated in various matrices.

 

Sample Type	Range(%)	Average Recovery(%)
Serum(n=8)	84-101	96
Plasma(n=8)	92-106	103

 

| Linearity

Samples were spiked with high concentrations of Human CPA3 and diluted with Universal Diluent to produce samples with values within the range of the assay.

 

		Serum(n=4)	Plasma(n=4)
1 : 2	Range (%)	85-94	88-96
	Average (%)	91	93
1 : 4	Range (%)	89-103	87-108
	Average (%)	94	99