| Field | Specification |
|---|---|
| Target | |
| Alternative names | Cathepsin B; APP secretase; APPS; Cathepsin B1; CTSB; CPSB |
| UniProt # | |
| Host | |
| Clonality | |
| Isotype | |
| Reactivity | |
| Applications | |
| Immunogen | E.coli-derived human Cathepsin B/CTSB recombinant protein (Position: Q42-K339). |
| Molecular weight | |
| Purification | |
| Reconstitution | |
| Cellular localization | |
| Concentration | |
| Form | Lyophilized |
| Storage | |
| Catalog no. (Mfr.) | |
| Main SKU |
Product Overview
This rabbit polyclonal antibody targets cathepsin B (gene CTSB) in human, mouse and rat samples and is validated for Western blot, IHC, flow cytometry and ELISA. The predicted molecular weight is 37.8 kDa; the supplier reports observed bands at 23 kDa, 31 kDa.
Cathepsin B (CTSB) is a lysosomal cysteine protease that contributes to general protein turnover inside cells and can act as both an endopeptidase and a carboxypeptidase. It also helps release thyroid hormone from thyroglobulin. When secreted or mislocalized, it can degrade extracellular matrix, so it is studied in tumor invasion, inflammation and lysosomal cell death.
| Target | Cathepsin B (gene CTSB; UniProt P07858, human) |
|---|---|
| Host / Clonality / Isotype | Rabbit / Polyclonal / Rabbit IgG |
| Reactivity | Human, Mouse, Rat |
| Form | Lyophilized |
| Formulation | Per vial: 4 mg trehalose; 0.9 mg NaCl; 0.2 mg Na2HPO4 |
| Calculated MW | 37.8 kDa |
| Observed MW | 23 kDa, 31 kDa |
| Storage | As supplied: −20 °C for up to 12 months from receipt. After reconstitution: 4 °C for up to 1 month, or aliquot and keep at −20 °C for up to 6 months. Avoid repeated freeze–thaw cycles. |
Validated Applications
| Western blot | 0.25–0.5 µg/mL (Human, Mouse, Rat) |
|---|---|
| IHC (paraffin sections) | 2–5 µg/mL (Human, Mouse, Rat) |
| Flow cytometry (fixed cells) | 1–3 µg/1×106 cells (Human) |
| ELISA | 0.1–0.5 µg/mL |
Samples with a confirmed band (WB): human U87 cells, human HepG2 cells, human A549 cells, rat brain tissue, rat liver tissue, mosue liver tissue.
Recommended loading (WB): 20–40 µg of total protein per lane.
Conditions in the example images (WB): 5–20% gradient SDS-PAGE under reducing conditions, 30 µg lysate per lane, transfer to nitrocellulose membrane, blocking in 5% non-fat milk, primary antibody at 0.5 µg/mL overnight at 4 °C, HRP-conjugated secondary antibody at 1:5000, ECL detection.
Samples with confirmed staining (IHC): human liver cancer tissue, human rectal cancer tissue, human thyroid cancer tissue, mouse liver tissue, rat liver tissue.
Recommended antigen retrieval: heat-mediated, in TE buffer (pH 9.0); citrate buffer (pH 6.0) can be used instead.
Conditions in the example images (IHC): heat-mediated antigen retrieval in EDTA buffer (pH 8.0).
Samples with a confirmed signal (flow cytometry): SiHa cells.
Immunogen
Recombinant human Cathepsin B/CTSB fragment (Gln42–Lys339), expressed in E. coli.
Reactivity Notes
The supplier lists reactivity with human, mouse and rat. UniProt describes cathepsin B as secreted and also located in the lysosome, melanosome and apical cell membrane. Tissue expression noted by UniProt (human): Expressed in the stratum spinosum of the epidermis. The samples tested by the supplier (listed above) are a practical starting point for positive controls.
Safety
Customization & Add-ons: Can’t find the antibody you need—or require a custom format for your assay? We can help you source the best match or support custom antibody solutions for diverse research needs, including species and isotype selection, conjugations and labeling (e.g., HRP/AP, biotin, fluorophores), purification grade options (Protein A/G, affinity purified), formulation preferences (buffer selection, carrier-free, glycerol-free), custom concentrations and aliquoting, low-endotoxin options for cell-based work, and application-focused QC/validation support (project dependent). Click Talk to a Scientist to submit a request, email us at support@biohippo.com, or explore our Research Services for additional support—our team will follow up with feasibility details and next steps.
Dayun Yang et al. (2014) The molecular mechanism for effects of TiN coating on NiTi alloy on endothelial cell function. Biomaterials. 10.1016/j.biomaterials.2014.04.069
Shuqing Li et al. (2025) Discovery of Highly Potent and Orally Bioavailable Histone Deacetylase 3 Inhibitors as Immunomodulators and Enhancers of DNA-Damage Response in Cancer Therapy. Journal of Medicinal Chemistry. 10.1021/acs.jmedchem.4c02445
Qinying Liu et al. (2022) The marine natural product, dicitrinone B, induces apoptosis through autophagy blockade in breast cancer. International Journal of Molecular Medicine. 10.3892/ijmm.2022.5186
Jing Mo et al. (2025) Erythrabyssin II is identified as a novel late-stage autophagy inhibitor that reverses chemoresistance and promotes apoptosis in ovarian cancer. iScience. 10.1016/j.isci.2025.112801
Zhang Zhen-Yu et al. (2014) CTSB promotes porcine preadipocytes differentiation by degrading fibronectin and attenuating the Wnt/β-catenin signaling pathway. Molecular and Cellular Biochemistry. 10.1007/s11010-014-2111-6
Wang Han et al. (2024) Adiponectin attenuates H2O2-induced apoptosis in chicken skeletal myoblasts through the lysosomal-mitochondrial axis. In Vitro Cellular & Developmental Biology-Animal. 10.1007/s11626-024-00857-8
