Close
Close
Loading...
CONTACT US
:
:
:
Call us at:
:
:
:
Fax:
Email:

CD8A

Products

Loading...

All listed services and products are For Research Use Only. Do Not use in any diagnostic or therapeutic applications.

Background

The CD8 subunit alpha (CD8A) is an approximately 32-34 kDa type I transmembrane glycoprotein related to the immunoglobulin superfamily. The molecule that interacts with this peptide is encoded by the CD8A gene. The extracellular domain has considerable structural homology to the immunoglobulin light chain, and the protein is heavily modified with N-linked glycosylation that contributes significantly to its mature molecular weight. The core receptor function of CD8A in relation to the T cell receptor (TCR) would form its functional architecture on cytotoxic T lymphocytes (CTLs). On the cell surface, it is found in two main forms: as a homodimer (CD8 αα) with two alpha chains, or a heterodimer (CD8 αβ) consisting of one alpha chain and one CD8B chain. CD8αβ is the main form of CTLs on mature peripheral CTLs and binds MHC class I with higher affinity than CD8αα homodimer which can be found on intraepithelial lymphocytes, thymocytes, and some natural killer (NK) cell subsets. The binding of CD8A to the invariant α3 domain of MHC class I upon engagement of peptide-MHC class I complexes coincides with recruitment of LCK to the TCR-CD3 complex. This close range and spatial approximation trigger phosphorylation cascades which results in lymphokine production, cytolytic granule release, motility and clonal expansion.

Fig.1 CD8A structure. (OA Literature)Fig.1 Comparison of the full-length and truncated CD8A protein highlighting the position of the p.Arg107Ter variant.1

CD8A Protein Function: A Coreceptor at the Nexus of Antigen Recognition and T-Cell Fate

The biological relevance of CD8A spans multiple linked immunological contexts:

  • T-Cell Activation and Antigen Recognition: CD8A is the critical link between the TCR, which binds antigenic peptides in a central cavity of MHC class I molecules expressed and stabilized on APCs. CD8A increases TCR sensitivity but does not hinder peptide specificity by rapidly binding MHC class I α3 domain (kinetics two to three orders of magnitude faster than TCR-peptide-MHC interactions). The coreceptor thus serves to provide kinetic reinforcement that enables, as well as enhances, intracellular signaling while preserving the exquisite antigen specificity of TCR.
  • LCK Recruitment and Signal Initiation: The cytoplasmic tail of CD8A binds directly to LCK, the Src-family kinase responsible for phosphorylating ITAMs within the CD3 complex. The recruitment of downstream signalling thorough ZAP-70, LAT and PLCγ to induce calcium release, MAPK activation and NFAT nuclear translocation. This spindle-like assembly can conduct signalosome, and its efficiency is a rate-limiting factor for CTL activa- tion threshold and effector potency.
  • T-Cell Quiescence and Survival: CD8A is involved in maintaining quiescence of naive T cells and memory T cells. Recent studies have shown that CD8α binds to PILRα (paired immunoglobulin-like type 2 receptor alpha) on stromal cells in the absence of cognate antigen, maintaining a non-activated state. If this interaction is lost, or if CD8α would be genetically deleted, CTL rapidly upregulate activation markers and Fas expression and undergo accelerated programmed cell death which illustrates that CD8A is required both for CTL activation as well as their survival in the resting pool of CTLs.

CD8A Membrane Protein Product

Drive your immunology and cell biology research with our catalog of recombinant CD8A proteins. The extracellular IgV-like domain and membrane-associated organization of CD8A are important considerations for studies of its interactions and biological function. We provide CD8A protein constructs and preparations suitable for a range of research applications, including structural studies, MHC class I binding assays, antibody development and characterization, and related biochemical analyses. Available construct formats may vary according to specific experimental requirements, with appropriate quality assessment applied based on the intended research use.

CD8A Protein Product

Not finding the membrane protein product you need? Contact us to start your one-stop custom service!

CD8A Stable Cell Line Product

Robust and reproducible cellular models are critical for dissecting CD8A-driven biology and assessing candidates. Our stable cell lines engineered to express wild-type or variant forms of human, mouse and rat CD8A as well as loss-of-function lines with modulated endogenous expression. These platforms are designed for superior throughput T-cell activation assays, MHC class I tetramer binding studies quantification and phenotyping of tumor-infiltrating lymphocytes between various experimental phases ensuring high consistency.

CD8A Stable Cell Line Product

Not finding the stable cell line product you need? Contact us to start your one-stop custom service!

CD8A Recombinant Antibody Product

We provide recombinant antibodies targeting CD8A for a range of research applications. These antibodies are produced using recombinant technologies that support consistent reagent quality and batch-to-batch reproducibility. Depending on the specific product and supporting datasheet, CD8A recombinant antibodies may be suitable or available for applications including Western Blotting (WB), ELISA, Flow Cytometry (FCM), Immunofluorescence/Immunocytochemistry (IF/ICC), Immunohistochemistry (IHC), and Immunoprecipitation (IP), supporting the detection and analysis of CD8A in appropriate research samples.

CD8A Recombinant Antibody Product

Not finding the recombinant antibody product you need? Contact us to start your one-stop custom service!

Product Features

  • High Purity & Activity: High purity and verified integrity for dependable downstream work.
  • Diverse Expression Systems: Choice of expression formats to match routine or specialized projects.
  • Species Reactivity: Products available for human, mouse, pig, and other species.
  • Validated Applications: Application-tested to deliver consistent signals across common lab workflows.
  • Exceptional Lot-to-Lot Consistency: Tight lot-to-lot control for reproducible performance.
  • Customization Options: Flexible customization of tags, labels, or packaging upon request.

Custom CD8A Membrane Protein and Antibody Discovery Services

In addition to our catalog products, we provide custom services for membrane protein & antibody discovery & development. With our deep knowledge of T-cell receptor biology, immuno-oncology and CD8+ T cells we can help you with:

  • Custom CD8A Receptor Production: Tailored expression, purification, and characterization of challenging multi-domain receptor constructs.
  • Custom Antibody Development: From antigen design to antibody engineering (monoclonal, polyclonal, recombinant) for specific research applications.
  • Stable Cell Line Development: Generation of bespoke stable cell lines expressing your target of interest.
  • Functional Assay Development: Designing and executing assays to assess receptor activation and ligand.

Frequently Asked Questions (FAQ)

  1. Do antibodies exist which differentiate the CD8A-CD8B heterodimer from both CD8A homodimeric species?

    Yes, we offer pairing-state-selective antibodies that are directed against a conformational epitope in the CD8A stalk region which is exposed after proper heterodimerization with CD8B but is sterically masked in the homodimeric form.

  2. Can your anti-CD8A antibodies be used for IHC of FFPE Thymic cortex or tumor-infiltrating lymphocyte sections?

    Yes, some clones have been validated on archival specimens following antigen retrieval and provided unique patterns of membranous staining visualized in cortical thymocytes or cytotoxic T-cell infiltrate. Peptide competition and recombinant antigen controls demonstrate the specificity of these majority of identity-based, cross-tool epitopes across heterogeneous tissue contexts.

  3. Is the recombinant CD8A ectodomain that you provide in a formulation ready to apply directly onto tissue-culture surfaces or biosensor chips for assays of MHC class I tetramer binding?

    Yes, the protein is in a buffer at defined concentration and physiologic pH with no carrier proteins or denaturants; it is also endotoxin monitored. So that means they can be diluted immediately into a coating buffer or used in an amine-coupling reaction without the need for dialysis or other intermediary buffer exchanges.

  4. Are your CD8A products suitable for clinical or diagnostic use?

    No, all CD8A products and services are only for research use and not approved for in vitro diagnostics (IVD) or clinical diagnosis, prevention, treatment, cure of any disease.

Reference
  1. Asseri, Ali A., et al. "A Novel Homozygous Truncating CD8A Variant (p. Arg107Ter) in a Patient with Recurrent Sinopulmonary Infections: A Case Report and Literature Review." Healthcare. Vol. 14. No. 7. MDPI, 2026. Under Open Access license CC BY 4.0, without modification. https://doi.org/10.3390/healthcare14070969
Our customer service representatives are available 24 hours a day, 7 days a week. Contact Us
© 2026 Creative Biolabs. | Contact Us
;