| Field | Specification |
|---|---|
| Mfr No | |
| Clonality | |
| Conjugate | |
| Host | |
| Isotype | |
| Product Type | |
| Reactivity | |
| Storage | |
| Target |
Overview
CD81 APC is a Mouse monoclonal targeting CD81, supplied as a APC format for FC workflows. It supports measurement of Human target expression in common experimental systems.
Key elements and design rationale
- Clone: CBI.164 — consistent clone identity can support panel reproducibility and cross-study comparisons.
- Isotype: IgG2a, k — informs selection of matched controls and secondary reagents when relevant.
- Conjugate: APC — enables direct detection in fluorescence-based assays. Excitation is typically matched to Red (633nm) lasers in cytometer configurations.
- Host species: Mouse — useful for panel design and control strategy planning.
- Reactivity: Human — interpret staining in the context of species-specific sequence and expression differences.
Key specifications such as clone identity, isotype, and fluorophore conjugation help researchers align panel design, control selection, and instrument configuration with the biological question and sample type.
Biological background
CD81, also known as Target of the Antiproliferative Antibody 1 (TAPA-1) or Tetraspanin-28 (TSPAN28), is a 26 kDa transmembrane protein belonging to the tetraspanin (TM4SF) family. It plays a role in cell growth, signal transduction, and immune cell interactions. CD81 is widely expressed across various cell types, including hematopoietic, neuroectodermal, and mesenchymal cells. Within the immune system, it is found on B and T lymphocytes, NK cells, thymocytes, eosinophils, monocytes, dendritic cells, and endothelial cells, while being absent from neutrophils, platelets, and erythrocytes. Functionally, CD81 is involved in B cell adhesion through VLA-4 integrin and contributes to early T cell development. It forms a multimolecular complex with other cell-surface proteins, including CD19, CD21, CD20, CD37, CD53, and CD82 in B cells, as well as CD4, CD8, and CD82 in T cells. Studies indicate that CD81-specific antibodies can exert antiproliferative effects on lymphoid cell lines, particularly large cell lymphomas, and promote homotypic cell aggregation. Additionally, CD81 interacts with CD19, CD21, and CD225, playing a key role in B cell activation and growth regulation. Anti-CD81 (CBI.164) is a recombinant antibody.
Research relevance and current trends
- High-parameter immunophenotyping: combining CD81 with complementary lineage and activation markers to resolve complex cell states.
- Panel standardization and data comparability: increasing emphasis on consistent reagents, compensation-aware fluorophore choices, and shared gating strategies.
- Integration with single-cell multi-omics: pairing surface marker profiling with transcriptomic or proteomic readouts to connect phenotype to function.
Common research applications
- Flow cytometry: quantify CD81-positive populations and compare expression distributions across conditions or time points.
- Cell sorting: enrich CD81-defined subsets for downstream RNA/protein assays or functional readouts.
Changes in measured signal are typically interpreted in the context of cell subset frequency, activation/differentiation state, and sample processing effects rather than as a standalone readout.
Notes for experimental interpretation
- Fluorophore selection: consider brightness, spectral overlap, and instrument configuration; compensation and spillover can affect apparent population boundaries.
- Biology-driven confounders: activation state, differentiation, and isoform/PTM variation can shift epitope accessibility and apparent expression.
- Control concepts: include matched isotype and fluorescence-minus-one (FMO) controls where appropriate, and interpret results alongside biological positive/negative reference samples.
For antibody-based assays, monoclonal versus polyclonal format can influence epitope recognition breadth and signal consistency. Conjugated antibodies support direct detection and can simplify multicolor panel design when paired with appropriate controls and instrument settings.
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.
