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To Purchase # 5717SC

5717SC 10 µg (With Carrier) $199.00
5717SF 10 µg (Carrier Free) $199.00
5717LC 50 µg (With Carrier) $599.00
5717LF 50 µg (Carrier Free) $599.00


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Source / Purification

Recombinant human Cystatin C (hCystatin C) Ser27-Ala146 (Accession #NP_000090) was expressed in human 293 cells at Cell Signaling Technology.

Product Description


>98% as determined by SDS-PAGE of 6 μg reduced (+) and non-reduced (-) recombinant hCystatin C. All lots are greater than 98% pure.

Molecular Formula:

Recombinant hCystatin C does not have a Met on the amino terminus and has a calculated MW of 13,347. DTT-reduced and non-reduced protein migrate as 14 kDa polypeptides. The expected amino-terminal SSPGK of recombinant hCystatin C was verified by amino acid sequencing.


The activity of hCystatin C was determined by assessing its ability to inhibit papain-mediated cleavage of a fluorogenic subtrate. The ED50 of each lot 1-12 nM.


Less than 0.01 ng endotoxin/1μg hCystatin C.

Product Usage Information


With carrier: Lyophilized from a 0.22 μm filtered solution of PBS, pH 7.2 containing 20 μg BSA per 1 μg hCystatin C. Carrier free: Lyophilized from a 0.22 μm filtered solution of PBS, pH 7.2.

Storage: Stable in lyophilized state at 4°C for 1 year after receipt. Sterile stock solutions reconstituted with carrier protein are stable at 4°C for 2 months and at -20°C for 6 months. Avoid repeated freeze-thaw cycles.Maintain sterility. Storage at -20°C should be in a manual defrost freezer.

Cystatin C is a 14 kDa member of the Cystatin superfamily of cysteine protease inhibitors (1). Most cell types secrete Cystatin C (1). Cystatin C inhibits cathepsins, and thereby may function as a tumor suppressor by inhibiting cathepsin mediated tumor cell invasion (2). In addition, this tumor suppressor function can also be attributed to Cystatin C's ability to antagonize TGF-β1 signaling (2,3). Cystatin C may also modulate antigen presentation through its ability to inhibit cathepsins (4). Cystatin C is also a biomarker for kidney dysfunction (5).

1.  Keppler, D. (2006) Cancer Lett 235, 159-76.

2.  Sokol, J.P. and Schiemann, W.P. (2004) Mol Cancer Res 2, 183-95.

3.  Tian, M. and Schiemann, W.P. (2009) Transl Oncol 2, 174-83.

4.  Vray, B. et al. (2002) Cell Mol Life Sci 59, 1503-12.

5.  Madero, M. and Sarnak, M.J. (2009) Curr Opin Nephrol Hypertens 18, 258-63.

Entrez-Gene Id 1471
Swiss-Prot Acc. P01034

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.

Human Cystatin C (hCystatin C)