Gene
CD4
Uniprot
P01730
Protein
T-cell surface glycoprotein CD4
See alternative names T-cell surface antigen T4/Leu-3
Uniprot Function Description
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 II molecule:peptide complex. The antigens presented by class II peptides are derived from extracellular proteins while class I peptides are derived from cytosolic proteins. Interacts simultaneously with the T-cell receptor (TCR) and the MHC class II 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 T-helper cells. In other cells such as macrophages or NK cells, plays a role in differentiation/activation, cytokine expression and cell migration in a TCR/LCK-independent pathway. Participates in the development of T-helper cells in the thymus and triggers the differentiation of monocytes into functional mature macrophages.
(Microbial infection) Primary receptor for human immunodeficiency virus-1 (HIV-1) (PubMed:2214026, PubMed:16331979, PubMed:9641677, PubMed:12089508). Down-regulated by HIV-1 Vpu (PubMed:17346169). Acts as a receptor for Human Herpes virus 7/HHV-7 (PubMed:7909607).
Sample type
Recommended sample types are EDTA plasma and serum. A range of additional sample types are compatible with the technology (PEA), including citrate plasma, heparin plasma, cerebrospinal fluid, (CSF), tissue and cell lysates, fine needle biopsies, microdialysis fluid, cell culture media, dried blood spots, synovial fluid, saliva, plaque extract and microvesicles. Please note that protein expression levels are expected to vary in different sample types. Certain assays are differentially affected by interfering substances such as hemolysate. Download any of our Data Validation documents or contact support@olink.com for more information.
Precision
Precision (repeatability) is calculated from linearized NPX values over LOD.
Analytical measuring range
The technical data reported below refers to the measured value in the in vitro validation assays run using known concentrations of recombinant antigen. Please note that these figures are for reference only and CANNOT be used to convert NPX values to absolute concentrations for proteins measured in plasma or serum samples.
Sensitivity plot
The calibrator curve shown below visualizes the analytical measuring range data based on in vitro measurement of recombinant antigen. Please note that this is shown for reference only and CANNOT be used to convert NPX values to absolute concentrations for proteins measured in plasma or serum samples. The vertical dotted lines represent LLOQ and ULOQ respectively, and the horizontal line indicates the LOD.
Biomarker Validation Data
Additional validation data, as well as a more detailed description of how the Olink panels are quality controlled can be found in our Data Validation documents – go to Document download center