Name :
Recombinant Human CD4 Protein (ECD, hFc Tag), HPLC-verified
Biological Activity :
Background :
T-cell surface glycoprotein CD4, is a single-pass type I membrane protein. CD4 contains three Ig-like C2-type (immunoglobulin-like) domains and one Ig-like V-type (immunoglobulin-like) domain. CD4 is a glycoprotein expressed on the surface of T helper cells, regulatory T cells, monocytes, macrophages, and dendritic cells. The CD4 surface determinant, previously associated as a phenotypic marker for helper/inducer subsets of T lymphocytes, has now been critically identified as the binding/entry protein for human immunodeficiency viruses (HIV). The human CD4 molecule is readily detectable on monocytes, T lymphocytes, and brain tissues. All human tissue sources of CD4 bind radiolabeled gp120 to the same relative degree; however, the murine homologous protein, L3T4, does not bind the HIV envelope protein. CD4 is a co-receptor that assists the T cell receptor (TCR) to activate its T cell following an interaction with an antigen-presenting cell. Using its portion that resides inside the T cell, CD4 amplifies the signal generated by the TCR. CD4 interacts directly with MHC class II molecules on the surface of the antigen-presenting cell via its extracellular domain. The CD4 molecule is currently the object of intense interest and investigation both because of its role in normal T-cell function, and because of its role in HIV infection. CD4 is a primary receptor used by HIV-1 to gain entry into host T cells. HIV infection leads to a progressive reduction of the number of T cells possessing CD4 receptors.Viral protein U (VpU) of HIV-1 plays an important role in downregulation of the main HIV-1 receptor CD4 from the surface of infected cells. Physical binding of VpU to newly synthesized CD4 in the endoplasmic reticulum is an early step in a pathway leading to proteasomal degradation of CD4. Amino acids in both helices found in the cytoplasmic region of VpU in membrane-mimicking detergent micelles experience chemical shift perturbations upon binding to CD4, whereas amino acids between the two helices and at the C-terminus of VpU show no or only small changes, respectively. Paramagnetic spin labels were attached at three sequence positions of a CD4 peptide comprising the transmembrane and cytosolic domains of the receptor. VpU binds to a membrane-proximal region in the cytoplasmic domain of CD4.
Biological Activity :
Measured by the ability of the immobilized protein to support the adhesion of NIH-3T3 mouse embryonic fibroblast cells.When 5×10^4 cells/well are added to CD4-Fc-coated plates (1.25μg/mL, 100 μL/well),approximately 20%-50% cells will adhere after 30 minutes at 37℃.
Expression Host :
Human
Source :
HEK293 Cells
Tag :
Protein Accession No. :
NP_000607.1
NCBI Gene ID :
Synonyms :
Synonyms :
CD4 molecule
Amino Acid Sequence :
Molecular Weight :
The recombinant human CD4 consists of 603 amino acids and predicts a molecular mass of 67.4 kDa.
Purity :
≥ 95 % as determined by SDS-PAGE. ≥ 90 % as determined by SEC-HPLC.
State of Matter :
Product Concentration :
Storage and Stability :
Samples are stable for up to twelve months from date of receipt at -20℃ to -80℃. Store it under sterile conditions at -20℃ to -80℃. It is recommended that the protein be aliquoted for optimal storage. Avoid repeated freeze-thaw cycles.
Endotoxin Level :
< 1.0 EU per μg protein as determined by the LAL method.
Protein Construction :
A DNA sequence encoding the human CD4 (NP_000607.1) (Met1-Trp390) was expressed with the Fc region of human IgG1 at the C-terminus.
Buffer Solution :
Lyophilized from sterile PBS, pH 7.4.Please contact us for any concerns or special requirements. Normally 5 % – 8 % trehalose, mannitol and 0.01% Tween80 are added as protectants before lyophilization. Please refer to the specific buffer information in the hardcopy of datasheet.
Shipping :
In general, recombinant proteins are provided as lyophilized powder which are shipped at ambient temperature.Bulk packages of recombinant proteins are provided as frozen liquid. They are shipped out with blue ice unless customers require otherwise.
Redissolution :
A hardcopy of datasheet with reconstitution instructions is sent along with the products. Please refer to it for detailed information.
Synonyms :
CD4mut Protein, Human CD4 背景信息 T-cell surface glycoprotein CD4, is a single-pass type I membrane protein. CD4 contains three Ig-like C2-type (immunoglobulin-like) domains and one Ig-like V-type (immunoglobulin-like) domain. CD4 is a glycoprotein expressed on the surface of T helper cells, regulatory T cells, monocytes, macrophages, and dendritic cells. The CD4 surface determinant, previously associated as a phenotypic marker for helper/inducer subsets of T lymphocytes, has now been critically identified as the binding/entry protein for human immunodeficiency viruses (HIV). The human CD4 molecule is readily detectable on monocytes, T lymphocytes, and brain tissues. All human tissue sources of CD4 bind radiolabeled gp120 to the same relative degree; however, the murine homologous protein, L3T4, does not bind the HIV envelope protein. CD4 is a co-receptor that assists the T cell receptor (TCR) to activate its T cell following an interaction with an antigen-presenting cell. Using its portion that resides inside the T cell, CD4 amplifies the signal generated by the TCR. CD4 interacts directly with MHC class II molecules on the surface of the antigen-presenting cell via its extracellular domain. The CD4 molecule is currently the object of intense interest and investigation both because of its role in normal T-cell function, and because of its role in HIV infection. CD4 is a primary receptor used by HIV-1 to gain entry into host T cells. HIV infection leads to a progressive reduction of the number of T cells possessing CD4 receptors.Viral protein U (VpU) of HIV-1 plays an important role in downregulation of the main HIV-1 receptor CD4 from the surface of infected cells. Physical binding of VpU to newly synthesized CD4 in the endoplasmic reticulum is an early step in a pathway leading to proteasomal degradation of CD4. Amino acids in both helices found in the cytoplasmic region of VpU in membrane-mimicking detergent micelles experience chemical shift perturbations upon binding to CD4, whereas amino acids between the two helices and at the C-terminus of VpU show no or only small changes, respectively. Paramagnetic spin labels were attached at three sequence positions of a CD4 peptide comprising the transmembrane and cytosolic domains of the receptor. VpU binds to a membrane-proximal region in the cytoplasmic domain of CD4.
References & Citations :
Farrar WL, et al. (1988) Characterization of CD4 glycoprotein determinant-HIV envelope protein interactions: perspectives for analog and vaccine development. Crit Rev Immunol. 8(4): 315-39.Biddison WE, et al. (1989) CD4 expression and function in HLA class II-specific T cells. Immunol Rev. 109: 5-15.Singh SK, et al. (2012) Mapping the interaction between the cytoplasmic domains of HIV-1 viral protein U and human CD4 with NMR spectroscopy. FEBS J. 279(19):3705-14.
MedChemExpress (MCE) recombinant proteins include: cytokines, enzymes, growth factors, hormones, receptors, transcription factors, antibody fragments, etc. They are often essential for supporting cell growth, stimulating cell signaling pathways, triggering or inhibiting cell differentiation; and are useful tools for elucidating protein structure and function, understanding disease onset and progression, and validating pharmaceutical targets. At MedChemExpress (MCE), we strive to provide products with only the highest quality. Protein identity, purity and biological activity are assured by our robust quality control and assurance procedures.
Related category websites: https://www.medchemexpress.com/recombinant-proteins.html
Popular product recommendations:
NA/Neuraminidase Protein
CaMKII alpha/CAMK2A Protein
Popular categories:
C Chemokines
Ubiquitin-Specific Peptidase 20