Cystatin B/Stefin B Antibody (225228) [Unconjugated]

Western blot shows lysates of human colon tissue, SK‑BR‑3 human breast cancer cell line, and A549 human lung carcinoma cell line. PVDF membrane was probed with 2 µg/mL of Mouse Anti-Human Cystatin B Monoclonal Antibody (Catalog # MAB1408) followed by HRP-conjugated Anti-Mouse IgG Secondary Antibody (Catalog # HAF018). A specific band was detected for Cystatin B at approximately 12 kDa (as indicated). This experiment was conducted under reducing conditions and using Immunoblot Buffer Group 1.

Papain (0.1 µg/mL) activity is measured in the presence of Recombinant Human Cystatin B (0.53 µg/mL, Catalog # 1408-PI) that has been preincubated with increasing concentrations of Human Cystatin B Monoclonal Antibody (Catalog # MAB1408). The ND50 is typically 5.4 µg/mL.

Western blot shows lysates of HEK293T human embryonic kidney parental cell line and Cystatin B knockout HEK293T cell line (KO). PVDF membrane was probed with 2 µg/mL of Mouse Anti-Human Cystatin B Monoclonal Antibody (Catalog # MAB1408) followed by HRP-conjugated Anti-Mouse IgG Secondary Antibody (Catalog # HAF018). A specific band was detected for Cystatin B at approximately 12 kDa (as indicated) in the parental HEK293T cell line, but is not detectable in knockout HEK293T cell line. GAPDH (Catalog # MAB5718) is shown as a loading control. This experiment was conducted under reducing conditions and using Immunoblot Buffer Group 1.

• Reactivity: Hu
• Applications: WB, IP, B/N, KO
• Clone: 225228
• Clonality: Monoclonal
• Host: Mouse
• Conjugate: Unconjugated

Cystatin B/Stefin B Antibody (225228) [Unconjugated] Summary

• Immunogen: E. coli-derived recombinant human Cystatin B
  aa Met2-Phe98
  Accession # P04080
• Specificity: Detects human Cystatin B in Western blots and direct ELISAs. In Western blots, less than 5% cross-reactivity with recombinant human (rh) Cystatins A and S, recombinant mouse Cystatin B, rhFetuin A, and rhHPRG (Histidine-Proline-Rich Glycoprotein) is observed and approximately 5% to 10% cross-reactivity with rhCystatins C, D, E/M, SA, SN, and rhFetuin B is observed.
• Source: N/A
• Isotype: IgG2b
• Clonality: Monoclonal
• Host: Mouse
• Gene: CSTB
• Purity Statement: Protein A or G purified from hybridoma culture supernatant

Applications/Dilutions

• Dilutions:
  • Immunoprecipitation 25 ug/mL
  • Knockout Validated
  • Neutralization 5.4 ug/mL
  • Western Blot 2 ug/mL

Packaging, Storage & Formulations

• Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
  • 12 months from date of receipt, -20 to -70 °C as supplied.
  • 1 month, 2 to 8 °C under sterile conditions after reconstitution.
  • 6 months, -20 to -70 °C under sterile conditions after reconstitution.
• Buffer: Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose. *Small pack size (SP) is supplied either lyophilized or as a 0.2 µm filtered solution in PBS.
• Preservative: No Preservative
• Reconstitution Instructions: Reconstitute at 0.5 mg/mL in sterile PBS.

Notes

This product is produced by and ships from R&D Systems, Inc., a Bio-Techne brand.

Alternate Names for Cystatin B/Stefin B Antibody (225228) [Unconjugated]

• CPI-B
• CST6cystatin B (liver thiol proteinase inhibitor)10STFBcystatin-B
• CSTB
• cystatin B (stefin B)
• Cystatin B
• EPM1
• Liver thiol proteinase inhibitor
• PME
• Stefin B
• stefin-B

Background

Cystatin B, also called stefin B or liver thiol proteinase inhibitor, is a member of family 1 of the cystatin superfamily (1). Like Cystatin A, it is an intracellular inhibitor regulating the activities of cysteine proteases of the papain family such as cathepsins B, H and L (2). Mutations in the Cystatin B gene is the cause of progressive myoclonus epilepsy (EPM1) (3). Because of its expression patterns, Cystatin B can be used as a marker for certain cancers, such as glioblastoma tumors (4). It readily forms amyloid fibrils in vitro (5). The human Cystatin B consists of 98 amino acid residues (3).

1. Abrahamson, M. (1994) Methods Enzymol. 244:685.
2. Pol, E. and I. Bjork (1999) Biochemistry 38:10519.
3. Pennacchio, L.A. et al. (1996) Science 271:1731.
4. Zhang, R. et al. (2003) Glia 42:194.
5. Zerovnik, E. et al. (2002) Biochim. Biophys. Acta 1594:1.

Limitations

This product is for research use only and is not approved for use in humans or in clinical diagnosis. Primary Antibodies are guaranteed for 1 year from date of receipt.

Publications for Cystatin B/Stefin B Antibody (MAB1408)(2)

Publications using MAB1408

• Rodriguez-Franco EJ, Cantres-Rosario YM, Plaud-Valentin M, Romeu R, Rodriguez Y, Skolasky R, Melendez V, Cadilla CL, Melendez LM Dysregulation of macrophage-secreted cathepsin B contributes to HIV-1-linked neuronal apoptosis. PLoS ONE, 2012-05-31;7(5):e36571. 2012-05-31 [PMID: 22693552] (ICC, IHC-Fr, Human)
• Feldman AS, Banyard J, Wu CL, McDougal WS, Zetter BR Cystatin B as a tissue and urinary biomarker of bladder cancer recurrence and disease progression. Clin. Cancer Res., 2009-02-01;15(3):1024-31. 2009-02-01 [PMID: 19188175] (Western Blot, Human)

Bioinformatics

• Gene Symbol: CSTB
• Uniprot:
  • P04080()