Anti-CD81 Rabbit PolymAb® for WB, IHC-P, ELISA - P60033

Core Product Specifications and Parameters

Biological Background: CD81 Function and Localization

• CD81 is a 26-kDa tetraspanin (TAPA-1/TSPAN28) that acts as a structural component of tetraspanin-enriched microdomains (TERMs), platforms for receptor clustering and signal transduction at the plasma membrane. Related references: PMID:16449649 PMID:20237408 PMID:27881302

• On activated B cells, CD81 enables the assembly of CD19-CR2/CD21 and B cell receptor (BCR) complexes within TERMs, lowering the threshold for antigen-induced clonal expansion and antibody production. Related references: PMID:15161911 PMID:20237408

• In T cells, CD81 facilitates localization of CD247/CD3 zeta at antigen-induced synapses with B cells, providing costimulation and promoting T helper type 2 polarization. Related references: PMID:22307619 PMID:23858057 PMID:8766544

• CD81 is present in MHC class II compartments and may contribute to antigen presentation. Related references: PMID:8409388 PMID:8766544

• CD81 serves as a hepatocyte receptor for hepatitis C virus (HCV) by associating with CLDN1 to form the HCV entry complex.

• In macrophages, CD81 associates with CD9 and integrins, preventing cell–cell fusion and regulating integrin-mediated adhesion, relevant for inflammatory responses. Related references: PMID:12796480

• CD81 is expressed on B cells, T cells, hepatocytes, and monocytes/macrophages, consistent with its roles in immunity and viral pathogenesis. Related references: PMID:20237408 PMID:12483205 PMID:12796480 PMID:22307619

Experimental Guidance and Technical Tips

• The immunogen corresponds to amino acids 114–199, which encompasses the large extracellular loop (LEL) of CD81—a region critical for protein–protein interactions, including HCV E2 binding. For applications requiring native conformation, consider using non-denaturing conditions.
• For western blot (WB), CD81 often runs as a diffuse band ~26 kDa due to glycosylation and palmitoylation; non-reducing sample preparation may help preserve disulfide-linked epitopes.
• In immunohistochemistry (IHC‑P), antigen retrieval methods should be optimized for the intended tissue; background may vary with fixation and endogenous peroxidase activity.
• For ELISA, this antibody can be used as a capture or detection reagent; validate the assay format with recombinant CD81 protein and biological samples.
• Cross-reactivity with mouse and rat CD81 is predicted, but confirm performance in the relevant sample system for these species.

CamelBio: Your One-Stop Sourcing Bridge

CamelBio is your dedicated partner for IVD raw-material sourcing, supporting diagnostic developers and researchers from discovery to clinical application. This CD81 Rabbit PolymAb® is designed for investigations into B‑cell biology, viral entry mechanisms, and immune synapse formation. Beyond this product, CamelBio offers validated antibody pairs, optimized recombinant antibodies, bulk ancillary reagents, and assistance in sourcing rare‑target raw materials to advance your IVD pipeline.