CD4 Products

CD4 Antibody (GK1.5)
CD4 Antibody (GK1.5)
Species: Mu
Applications: Flow, Flow-CS, ICC/IF, IHC, IHC-Fr, In vivo, IP, B/N
Host: Rat Monoclonal
Human CD4 ELISA Kit (Colorime ...
Human CD4 ELISA Kit (Colorimetric)
Species: Hu
Applications: ELISA
Mouse CD4 ELISA Kit (Colorime ...
Mouse CD4 ELISA Kit (Colorimetric)
Species: Mu
Applications: ELISA
Rat CD4 ELISA Kit (Colorimetr ...
Rat CD4 ELISA Kit (Colorimetric)
Species: Rt
Applications: ELISA
CD4 Overexpression Lysate
CD4 Overexpression Lysate
Species: Hu
Applications: WB
Recombinant Human sCD4 Protei ...
Recombinant Human sCD4 Protein
Species: Hu
Applications: Bioactivity
Formulation Catalog # Availability Price  
Recombinant Human CD4 Protein ...
Recombinant Human CD4 Protein
Species: Hu
Applications: PAGE
Recombinant Canine CD4 Protei ...
Recombinant Canine CD4 Protein, CF
Species: Ca
Formulation Catalog # Availability Price  


The T cell receptor (TCR) is a heterodimer composed of either alpha and beta or gamma and delta chains. CD3 chains and the CD4 or CD8 co-receptors are also required for efficient signal transduction through the TCR. The TCR is expressed on T helper and T cytotoxic cells that can be distinguished by their expression of CD4 and CD8; T helper cells express CD4 proteins and T cytotoxic cells display CD8. CD4 is also expressed on cortical cells, mature medullary thymocytes, microglial cells and dendritic cells. CD4 (also designated T4 and Leu 3) is a membrane glycoprotein that contains four extracellular immunoglobin-like domains. The TCR in association with CD4 can bind class II MHC molecules presented by the antigen-presenting cells. The CD4 protein functions by increasing the avidity of the interaction between the TCR and an antigenclass II MHC complex. An additional role of CD4 is to function as a receptor for HIV.


Entrez Human
Uniprot Human
Product By Gene ID 920
Alternate Names
  • CD4mut
  • CD4 antigen
  • T-cell surface antigen T4/Leu-3
  • T-cell surface glycoprotein CD4
  • CD4 antigen (p55)
  • CD4 receptor
  • CD4 molecule

Research Areas for CD4

Find related products by research area and learn more about each of the different research areas below.

Adaptive Immunity
CD Markers
Cell Biology
Cellular Markers
Cytokine Research
Stem Cell Markers

Bioinformatics Tool for CD4

Discover related pathways, diseases and genes to CD4. Need help? Read the Bioinformatics Tool Guide for instructions on using this tool.
Vizit™, under license from BioVista Inc.

Related CD4 Blog Posts

Check out the latest blog posts on CD4.
Success of combined IL-10 and IL-12 therapy in colon cancer depends on IFN-gamma and gut barrier integrity
By Jamshed Arslan, Pharm. D., PhD. Colon cancer is responsible for over 600,000 deaths per year worldwide. Colon cancer can be classified into two categories: mismatch repair (MMR)-deficient and MMR-proficient cancers...    Read more.
mTOR Signaling and the Tumor Microenvironment
By Yoskaly Lazo-Fernandez, PhD The mammalian target of rapamycin (mTOR) is a conserved serine/threonine kinase that, as a member of two distinct intracellular protein complexes, mTORC1 and mTORC2, regulates protein...    Read more.
Flow Cytometry Basics for the Non-Expert
By Jody Bonnevier, PhD.Flow cytometry: A Challenging Interdisciplinary ApplicationFlow cytometry has long been the cell analysis method of choice for immunologists, however more and more disciplines have recognize...    Read more.
The role of MHC Class II RT1B and immune response post brain injury
The major histocompatibility complex (MHC) is responsible for binding peptide fragments arising from pathogens in order to display them on the cell surface for recognition from immune cells.  Once recognized, the foreign pathogen is typically evade...    Read more.
Topics in CD11b: The innate immune response
Integrins are transmembrane receptors composed of alpha and beta chains, where beta-integrins are mainly expressed in leukocytes. Leukocytes are white blood cells that act in the immune system to defend our body against foreign pathogens.  Integrin...    Read more.
Transferrin and the blood brain barrier
Transferrin, an iron binding protein that facilitates iron uptake in cells, is an integral part of a mechanism that may introduce antibody therapies to the central nervous system. Currently, the brain’s ability to take in antibody therapies i...    Read more.
MHC Class I and the Herpes Simplex Virus
MHC molecules (also known as major histocompatibility complex molecules) assist in the presentation of antigens to T cells in order to eradicate foreign pathogens.  These molecules are highly polymorphic, meaning that they exist in multiple varian...    Read more.
CD3 (OKT3) as a marker of immune response efficiency
Our immune system is a powerful defense mechanism against infection, however different variables can cause our immune response to work for or against us.  CD3 (cluster of differentiation 3) is one component of our immune signal response that is co...    Read more.
CD20 (Cluster of differentiation 20, Membrane-spanning 4-domains subfamily A member 1 (MS4A1), CVID5, B-lymphocyte surface antigen B1)
CD20 is a human B-lymphocyte surface molecule that spans the membrane four times and is expressed on both normal and malignant cells. The CD20 antigen displays a unique expression pattern among hematopoietic cells - it is present on human pre B-ly...    Read more.
CD8 alpha - Marker for cytotoxic T lymphocytes
The T-cell co-receptor CD8 is a cell-surface glycoprotein that bridges the lipid bilayer by interacting externally with ligands, such as major histocompatibility complex (MHC) class I, as well as internally with signaling molecules such as tyrosine ki...    Read more.
Lymphocyte activation gene 3 (LAG3): No lag time in immune response
The LAG3 protein belongs to the Ig superfamily and contains 4 extracellular Ig-like domains (D1-D4). This molecule plays an key role in the immune response through negative regulation of T-cell proliferation, function, and homeostasis. It is required...    Read more.
CD4 - An Important Co-receptor Assisting TCRs
The cluster of differentiation 4 (CD4) protein is a surface, type I membrane-embedded glycoprotein that is found on a wide range of cells: T-lymphocytes, B-cells, macrophages, granulocytes, and developmentally-dependent regions specific to the brain....    Read more.
CD4, HIV and T Cell Signaling
CD4, also known as Cluster of Differentiation 4, interacts with major histocompatibility complex class II antigens, acts as a receptor for the human immunodeficiency virus and induces the aggregation of lipid rafts. It is expressed in T lymphocytes, B...    Read more.
FOXP3: Master Regulatory Transcriptional Factor
FOXP3, a forkhead family transcription factor specially expressed in regulatory T (Treg) cells, controls the expression of many key immune-regulatory genes. Treg cells are a population of T lymphocytes that have critical roles in the immune system hom...    Read more.
A Multicolored Approach to CD4 Antibody Assays
Novus Biologicals offers the widest selection of conjugated CD4 antibody products, with a database that's continually expanding to take into account the latest developments. This includes CD4 antibodies conjugated to Dynomics and PE fluorescent dyes,...    Read more.
Potential breakthrough in HIV research means therapeutic HIV antibodies may be coming soon.
Research antibodies have long been used to advance HIV/Aids research, however researchers at the California Institute of Technology have recently published a study [PMID: 22033520] developing a new antibody that may someday be used clinically to neutr...    Read more.
The CD4 Antibody: More than Just a Cellular Marker
CD4 is a member of the cluster of differentiation family of proteins, mainly expressed on the surface of thymocytes and a specific subset of mature T-cells. CD4 antibody studies have also shown it expressed on monocytes, cortical cells, microglial cel...    Read more.
Read more CD4 related blogs.