| CTSK

Cathepsin K, abbreviated CTSK, is an enzyme that is encoded by the CTSK gene.The protein encoded by this gene is a cysteine cathepsin, a lysosomal cysteine protease involved in bone remodeling and resorption. This protein, which is a member of the peptidase C1 protein family, is expressed predominantly in osteoclasts.Cathepsin K is a protease, which is defined by its high specificity for kinins, that is involved in bone resorption. The enzyme's ability to catabolize elastin, collagen, and gelatin allows it to break down bone and cartilage. This catabolic activity is also partially responsible for the loss of lung elasticity and recoil in emphysema. Cathepsin K inhibitors show great potential in the treatment of osteoporosis.
 

| 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 (ng/mL)	20	10	5	2.5	1.25	0.625	0.312	0
OD	2.33	1.76	1.16	0.7	0.46	0.33	0.24	0.1
Corrected OD	2.23	1.66	1.06	0.6	0.36	0.23	0.14	-

 

| Repeatability

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

| Recovery

The recovery of Pig CTSK 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	102

 

| Linearity

Samples were spiked with high concentrations of Pig CTSK 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 (%)	84-95	88-96
	Average (%)	91	93
1 : 4	Range (%)	89-103	87-108
	Average (%)	94	98