Product Details

Purity

≥ 95% as determined by SDS-PAGE.

Endotoxin

Less than 1.0 EU/ug as determined by LAL method.

Activity

Measured by its binding ability in a functional ELISA. Immobilized Human CD8A at 5 μg/mL can bind Anti-CD8A recombinant antibody (CSB-RA004966MA3HU). The EC50 is 11.49-20.78 ng/mL.

Target Names

CD8A

Uniprot No.

P01732

Alternative Names

T-cell surface glycoprotein CD8 alpha chain; T-lymphocyte differentiation antigen T8/Leu-2; CD8a; CD8A; MAL

Species

Homo sapiens (Human)

Source

Mammalian cell

Expression Region

22-182aa

Target Protein Sequence

SQFRVSPLDRTWNLGETVELKCQVLLSNPTSGCSWLFQPRGAAASPTFLLYLSQNKPKAAEGLDTQRFSGKRLGDTFVLTLSDFRRENEGYYFCSALSNSIMYFSHFVPVFLPAKPTTTPAPRPPTPAPTIASQPLSLRPEACRPAAGGAVHTRGLDFACD

Mol. Weight

19.0 kDa

Protein Length

Partial

Tag Info

C-terminal 10xHis-tagged

Form

Lyophilized powder
Note: We will preferentially ship the format that we have in stock, however, if you have any special requirement for the format, please remark your requirement when placing the order, we will prepare according to your demand.

Buffer

Lyophilized from a 0.2 μm sterile filtered PBS, 6% Trehalose, pH 7.4

Reconstitution

We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Please reconstitute protein in deionized sterile water to a concentration of 0.1-1.0 mg/mL.We recommend to add 5-50% of glycerol (final concentration) and aliquot for long-term storage at -20°C/-80°C. Our default final concentration of glycerol is 50%. Customers could use it as reference.

Troubleshooting and FAQs

Protein FAQs

Storage Condition

Store at -20°C/-80°C upon receipt, aliquoting is necessary for mutiple use. Avoid repeated freeze-thaw cycles.

Shelf Life

The shelf life is related to many factors, storage state, buffer ingredients, storage temperature and the stability of the protein itself.
Generally, the shelf life of liquid form is 6 months at -20°C/-80°C. The shelf life of lyophilized form is 12 months at -20°C/-80°C.

Lead Time

3-7 business days

Notes

Repeated freezing and thawing is not recommended. Store working aliquots at 4°C for up to one week.

Datasheet & COA

Please contact us to get it.

Description

CD8 alpha chain serves as the co-receptor for MHC class I molecules on cytotoxic T lymphocytes, making its extracellular domain (aa 22–182) essential for studying T-cell recognition and immune checkpoint interactions. Mammalian expression preserves the native glycosylation and disulfide bonding required for physiologically relevant antibody binding, as demonstrated by functional ELISA validation showing an EC50 of 11.49–20.78 ng/mL against an anti-CD8A recombinant antibody when immobilized at 5 μg/mL. This quantitative binding profile supports use in therapeutic antibody epitope mapping, competitive inhibition screening for biologics targeting CD8-expressing cells, and SPR or BLI affinity characterization experiments where conformational integrity directly impacts KD measurements. The protein meets the purity and endotoxin criteria typical for ligand-binding assays and blocking antibody validation, with >95% purity by SDS-PAGE and <1.0 EU/μg endotoxin.

Target Background

Function

Integral membrane glycoprotein that plays an essential role in the immune response and serves multiple functions in responses against both external and internal offenses. In T-cells, functions primarily as a coreceptor for MHC class I molecule:peptide complex. The antigens presented by class I peptides are derived from cytosolic proteins while class II derived from extracellular proteins. Interacts simultaneously with the T-cell receptor (TCR) and the MHC class I proteins presented by antigen presenting cells (APCs). In turn, recruits the Src kinase LCK to the vicinity of the TCR-CD3 complex. LCK then initiates different intracellular signaling pathways by phosphorylating various substrates ultimately leading to lymphokine production, motility, adhesion and activation of cytotoxic T-lymphocytes (CTLs). This mechanism enables CTLs to recognize and eliminate infected cells and tumor cells. In NK-cells, the presence of CD8A homodimers at the cell surface provides a survival mechanism allowing conjugation and lysis of multiple target cells. CD8A homodimer molecules also promote the survival and differentiation of activated lymphocytes into memory CD8 T-cells.

Gene References into Functions

Studied lymphocyte phenotype in resected lymph nodes of patients with lung cancer by analyzing levels of Foxp3 and CD8 by immunohistochemical staining. PMID: 28831395
This study compares the differences of PD-L1 expression and CD8+ tumor-infiltrating lymphocyte density, two major response biomarkers of PD-1/PD-L1 blockade, between paired primary and brain metastatic lesions in advanced non-small cell lung cancer (NSCLC). For NSCLC brain metastases patients, CD8+ tumor-infiltrating lymphocyte density showed a spatial and temporal heterogeneity. PMID: 29526752
Endometrioid endometrial carcinomas are capable of down-regulating CD8 expression by cytotoxic T lymphocytes. PMID: 27346574
The PD-1/CD8 ratio may, therefore, be a useful prognostic marker for stage II/III CRC. What is important for predicting the prognosis may be the PD-1/CD8 ratio rather than the absolute number of PD-1(+) tumor-infiltrating lymphocytes . PMID: 28739701
We also observed a significant association between forkhead box protein 3 ( p = 0.001) and the Neo-Bioscore, while only a marginal difference was observed with CD8+ expression ( p = 0.074). This study demonstrated that forkhead box protein 3 expression has value as the only independent marker that predicts a good response to neoadjuvant chemotherapy and that it is related with a good prognosis according to the Neo-Biosc PMID: 28621227
missense mutation increases susceptibility to recurrent respiratory infections PMID: 26563160
Human mesenchymal stromal cells enhance the immunomodulatory function of CD8(+)CD28(-) regulatory T cells. PMID: 25482073
Dendritic cells accumulate in the bone marrow of multiple myeloma patients and protect tumor plasma cells from CD8+ T-cell killing. PMID: 26185130
Patients with the presence of CD8- and CD45RO-positive T cells in bone marrow demonstrated better survival of gastric cancer patients than those with the absence of these cells in bone marrow. PMID: 25804232
More sCD8 circulating molecules were found in patients transfused with post-storage leucodepleted RBCs whose supernatants had large amounts of sHLA-I. sCD8 is a possible modulator of sHLA-I-mediated transfusion-related immunomodulation. PMID: 23356971
CD8-positivity proved to be an independent prognostic predictor of worse outcome in pediatric anaplastic lymphoma kinase-positive anaplastic large cell lymphoma. PMID: 23716548
CREMalpha orchestrates epigenetic remodeling of the CD8A,B through the recruitment of DNA methyltransferase (DNMT) 3a and histone methyltransferase G9a. PMID: 24297179
Modified CD8A gene function may contribute to the development of refractory chronic rhinosinusitis via reduction of circulating CD8 lymphocytes. PMID: 23640800
transcription factor cAMP-responsive element modulator alpha (CREMalpha), which is expressed at increased levels in T cells from systemic lupus erythematosus patients, contributes to transcriptional silencing of CD8A and CD8B. PMID: 24047902
The CD8(+)CCR7(+) T-cell frequency in HNSCC patients' blood tested at diagnosis can discriminate them from normal controls and predicts disease recurrence PMID: 23363813
The expression of human leucocyte antigen (HLA)-DR in epithelial cells and cluster of differentiation (CD8)-positive lymphocytes as possible markers of chronic ocular graft versus host disease, was investigated. PMID: 23878500
HIV-1 clade-B Nef peptides elicit increased frequency, breadth and function of CD8+ T-cells compared to consensus peptides PMID: 23185362
analysis of the effector phenotype of CD8+ T cells at the junction epithelium during clinical quiescence of herpes simplex virus 2 infection PMID: 22811543
study confirms that CD8 expression is a recurrent albeit rare phenomenon in patients with chronic lymphocytic leukemia and suggests that CD8 expression has an adverse prognostic impact PMID: 22143984
Silencing Hsp25/Hsp27 gene expression augments proteasome activity and increases CD8+ T-cell-mediated tumor killing and memory responses PMID: 22185976
LNX1 and LNX2 interact with CD8alpha and promote its ubiquitylation and endocytosis. PMID: 22045731
Nef-mediated down-modulation of CD8alphabeta is a fundamental property of primate lentiviruses. PMID: 22013062
Multiple sclerosis is characterized by a dysregulation of CD8+CD56-perforin+ T cells that may play a role in the development of disability. PMID: 22001684
Lymphoid tissue (LT)-resident CD8alpha-positive dendritic cells (DCs) and non(LT)-derived CD103-positive DCs express transgenic XCR1 and are characterized by a unique transcriptional fingerprint, irrespective of their tissue of origin. PMID: 21948982
Coreceptor CD8alphabeta contributes to the antigen-recognition process by binding to a largely invariant region of the MHC class I molecule and by promoting intracellular signaling. PMID: 21954283
These results suggest that the elevated frequency of PD-1(+) CD8(+) T cells could be associated with leukemic relapse in pediatric umbilical cord blood transplantation recipients. PMID: 21813446
The aim was to determine if SPARC, FOXP3, CD8 and CD45RO expression levels are associated with colorectal cancer (CRC) stage, disease outcome and long-term cancer-specific survival PMID: 21818290
we present the complex structures of human CD8alphaalpha bound to HLA-A*2402 PMID: 21645925
the presence of IL-1 and/or IL-6 during activation of human CD8 T cells attenuates Fas-mediated AICD, whereas IL-12 increases the susceptibility of activated CD8 T cells to this form of cell death PMID: 21518761
In the setting of HIV-induced lymphopenia, naive CD4-expressing T cells are recruited mainly into the proliferating pool in response to CD4 T cell depletion, whereas naive CD8-positive T cell proliferation is driven mainly by levels of HIV RNA. PMID: 21257970
Studies indicate that The thymus leukemia (TL) antigen and CD8alphaalpha are interacting surface molecules that are expressed at the frontline of the mucosal immune system. PMID: 20850477
PD-L1 and PD-L2 knockdown dendritic cells showed superior potential to expand minor histocompatibility antigen-specific CD8(+) effector and memory T cells from leukemia patients early after donor lymphocyte infusion and later during relapse. PMID: 20682852
The study shows that impaired Epstein-Barr virus-specific CD8+ T-cell function in X-linked lymphoproliferative disease is restricted to SLAM family-positive B-cell targets. PMID: 20644117
The positive rate of CD8 in primary lung cancer tissue was significantly higher than that in normal lung tissue. PMID: 20704820
Binding of the CD8 coreceptor to class I histocompatibility molecules significantly enhances the amount of calcium released from intracellular stores, triggered by a weaker ESO1 peptide agonist. PMID: 20053942
Four new weak but tissue-specific DNase I hypersensitivity sites have been mapped 0-0.8 kb upstream of the first exon of CD8A, in the promoter region. PMID: 11937547
Soluble HLA-A,-B,-C and -G molecules induce apoptosis in T and NK CD8+ cells and inhibit cytotoxic T cell activity through CD8 ligation. PMID: 12594841
expression of the HMG box protein TOX is sufficient to induce changes in coreceptor gene expression associated with beta-selection, including CD8 gene demethylation PMID: 15078895
Establishment of a permanent CD8+ cell line from a patient with leukemic phase of acute lymphoblastic lymphoma. PMID: 15927673
p32 recruits ganciclovir kinase to redistribute the nuclear lamina. PMID: 15975922
Introduction of CD8 alpha down-regulates the production of major T helper (Th) type 2 cytokines and may induce differentiation of tumor-specific Th1 cells to improve the clinical potential of T cell receptor (TCR) gene transfer to treat melanoma. PMID: 16818755
The results indicate that p.Gly111Ser is confined to the Spanish Gypsy population, where it occurs at a carrier rate of 0.4%. PMID: 17658607
human monocytes express CD8 alpha; co-engagement of CD8 alpha and FcR enhances monocyte TNF release, suggesting FcR may be a novel partner receptor for CD8 alpha on innate immune cells PMID: 17678538
CD8+FOXP3+ T cells play an important role in unresponsiveness related to upregulated interleukin receptors on dendritic cells. PMID: 18089323
Data suggest that Bim-mediated attrition of HBV-specific CD8(+) T cells contributes to the inability of these cell populations to persist and control viral replication. PMID: 18398508
tumor-induced TGF-beta may actively subvert the CD8+ arm of the immune system into directly promoting tumor growth by an IL-17-dependent mechanism PMID: 18483277
Data suggest that a decrease in CD8+CD28- T cells may reflect impaired T-cell suppression and accordingly, increased T cell help to autoreactive B cells in patients with systemic lupus erythematosus. PMID: 18625635
analysis of an interaction between B7-H3 and TLT-2 that preferentially enhances CD8(+) T cell activation PMID: 18650384
polarized CD8 T cells within the HBV-infected liver may impede proliferative antiviral effector function, while contributing to the proinflammatory cytokine environment PMID: 18695005
in patients with melanoma, who underwent a peptide-based vaccination, homodimer may represent a marker of antigen-specific T-cell memory PMID: 18833003

Hide All

Involvement in disease

CD8 deficiency, familial (CD8 deficiency)

Subcellular Location

[Isoform 1]: Cell membrane; Single-pass type I membrane protein.; [Isoform 2]: Secreted.

Tissue Specificity

CD8 on thymus-derived T-cells usually consists of a disulfide-linked alpha/CD8A and a beta/CD8B chain. Less frequently, CD8 can be expressed as a CD8A homodimer. A subset of natural killer cells, memory T-cells, intraepithelial lymphocytes, monocytes and

Database Links

HGNC: 1706

OMIM: 186910

KEGG: hsa:925

STRING: 9606.ENSP00000283635

UniGene: Hs.85258

Code	CSB-MP004966HUd7
Abbreviation	Recombinant Human CD8A protein, partial (Active)
MSDS	MSDS Datasheet
Size	$190
	Order now
Image	(Tris-Glycine gel) Discontinuous SDS-PAGE (reduced) with 5% enrichment gel and 15% separation gel. Activity Measured by its binding ability in a functional ELISA. Immobilized Human CD8A at 5 μg/ml can bind Anti-CD8A recombinant antibody (CSB-RA004966MA3HU). The EC₅₀ is 11.49-20.78 ng/mL. Biological Activity Assay
Have Questions?	Leave a Message or Start an on-line Chat

Recombinant Human T-cell surface glycoprotein CD8 alpha chain (CD8A), partial (Active)

Product Details

Related Products

Customer Reviews and Q&A

Target Background

×CloseMessage