Recombinant Human CD4 protein

Specifications

Form

Lyophilized

General info

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 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 : 12089508, PubMed : 16331979, PubMed : 2214026, PubMed : 9641677). Down-regulated by HIV-1 Vpu (PubMed : 17346169). Acts as a receptor for Human Herpes virus 7/HHV-7 (PubMed : 7909607).

Post-translational modifications

Palmitoylation and association with LCK contribute to the enrichment of CD4 in lipid rafts.. Phosphorylated by PKC; phosphorylation at Ser-433 plays an important role for CD4 internalization.