| Field | Specification |
|---|---|
| Target | |
| Alternative names | CD81 antigen; 26 kDa cell surface protein TAPA-1; Target of the antiproliferative antibody 1; Tetraspanin-28; Tspan-28; CD81; CD81; TAPA1; TSPAN28 |
| UniProt # | |
| Host | |
| Clonality | |
| Isotype | |
| Reactivity | |
| Applications | |
| Immunogen | E. coli-derived human TAPA1 recombinant protein (Position: F113-K201). |
| Molecular weight | |
| Reconstitution | |
| Cellular localization | |
| Concentration | |
| Form | Lyophilized |
| Storage | |
| Catalog no. (Mfr.) | |
| Main SKU |
Product Overview
This rabbit polyclonal antibody detects CD81 antigen in human, mouse and rat samples and is validated for Western blot, IHC and ELISA. The predicted molecular weight is 25.8 kDa, and the supplier reports an observed band at about 26 kDa.
CD81 is a widely expressed tetraspanin that organizes tetraspanin-enriched membrane microdomains. On B cells it partners with CD19 and CD21 to form the B-cell co-receptor complex, it is an entry factor for hepatitis C virus, and it is a common marker for exosomes.
| Target | CD81 antigen (gene CD81; UniProt P60033, 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 | 25.8 kDa |
| Observed MW | 26 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 | 0.1–0.5 µg/mL (Human, Mouse, Rat) |
|---|---|
| IHC (paraffin sections) | 2–5 µg/mL (Human) |
| ELISA | 0.1–0.5 µg/mL |
Samples with a confirmed band (WB): human PC-3 cells, human Ramos cells, human 293T cells, human Jurkat cells, rat PC-12 cells, rat C6 cells, mouse RAW264.7 cells, mouse ANA-1 cells.
Recommended loading (WB): 20–40 µg of total protein per lane.
Conditions in the example images (WB): 12% 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 tonsil tissue, human liver tissue, human testis tissu.
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).
Immunogen
Recombinant human TAPA1 fragment (Phe113–Lys201), expressed in E. coli.
Reactivity Notes
The supplier lists reactivity with human, mouse and rat. UniProt places CD81 antigen in the cell membrane and basolateral cell membrane. Tissue expression noted by UniProt (human): Expressed on B cells (at protein level). 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.
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