Stefin B Antibody

Overview

Stefin B Antibody is a research-use antibody directed against STEFIN B. It is supplied for use in common immunoassay contexts such as WB, IHC-P, FACS (RUO).

Key elements and design rationale

• Target: STEFIN B.
• Description (provided): Cystatin B (CSTB), also called STFB, is a small protein that is a member of the superfamily of cysteine protease inhibitors.
• Antibody type: Mouse, clone 2B6, Mouse IgG1.
• Format: Purified; Protein G affinity.
• Reported/predicted localization: Cytoplasm.
• Species reactivity: tested: Human.
• Immunogen (if provided): Human recombinant protein (amino acids M1-F98) was used as the immunogen for the Stefin B antibody..

The information above helps you match the antibody format to your assay context, interpret species-dependent differences, and anticipate how epitope context (isoforms, PTMs, or conformational state) may influence signal.

Biological background

Cystatin B (CSTB), also called STFB, is a small protein that is a member of the superfamily of cysteine protease inhibitors. It has been isolated from human spleen and liver and its amino acid sequence has been fully determined. The cystatin B gene is located on 21q22.3. It is widely distributed and is localized mostly intracellularly, but has been found extracellularly. The protein is able to form a dimer stabilized by noncovalent forces, inhibiting papain and cathepsins l, h and b. Its role is thought to be as a protector against the proteinases leaking from lysosomes. A cystatin B multiprotein complex might have a specific cerebellar function, and that the loss of this function might contribute to the etiopathogenesis of EPM1. Upon differentiation to myotubes, CSTB becomes excluded from the nucleus and lysosomes, suggesting that the subcellular distribution of CSTB is dependent on the differentiation status of the cell.

For curated annotations (gene/protein naming, domains, isoforms, and pathway links) for STEFIN B, consult primary databases such as UniProt, NCBI Gene, and Ensembl.

Research relevance and current trends

• Context-dependent expression studies: researchers often examine STEFIN B abundance and localization across perturbations (genetic, pharmacologic, or environmental) to connect phenotype to molecular changes.
• Reagent reproducibility: there is growing emphasis on antibody specificity checks using orthogonal approaches (e.g., genetic perturbation or independent antibodies) and transparent reporting of clone/lot information.
• Multi-modal datasets: antibody-based readouts are increasingly combined with transcriptomics and imaging to relate protein-level measurements to cell-state transitions.

Common research applications

• Western blotting (immunoblot) for relative detection of target protein abundance and apparent molecular weight.
• Immunohistochemistry for spatial mapping of target expression across tissues and cell types.
• FACS: commonly used to detect or compare STEFIN B across experimental conditions (conceptual guidance only).

When comparing conditions, interpret changes in signal in the context of sample composition, expected localization, and any known isoform complexity for the target.

Notes for experimental interpretation

• Isoforms and PTMs: alternative splicing or post-translational modifications can change epitope accessibility and apparent molecular weight; interpret bands/signals accordingly.
• Cross-reactivity and matrix effects: background binding can vary by sample type, species, and blocking/detection chemistries; include appropriate negative controls.
• Control concepts: where feasible, use genetic perturbation (KO/KD/overexpression), orthogonal assays, or independent antibodies to support specificity claims.

Antibody considerations: Polyclonal reagents may recognize multiple epitopes and can increase sensitivity but may show broader binding profiles, while monoclonal clones provide a single-epitope readout that can improve consistency across experiments. If a conjugate is listed, the antibody supports more direct detection workflows; otherwise, it is typically used with a compatible secondary antibody.

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.