描述:
CD40 is a type I transmembrane glycoprotein belonging to the TNF receptor superfamily. The
mature mCD40 consists of a 172 amino acid (aa) extracellular domain, a 22 aa transmembrane
region and a 90 aa cytoplasmic domain. CD40 is expressed on B cells, follicular dendritic cells,
dendritic cells, activated monocytes, macrophages, endothelial cells, vascular smooth muscle
cells and several tumor cell lines. The extracellular domain has the cysteinerich repeat regions,
which are characteristic for many of the receptors of the TNF superfamily. Interaction of CD40
with its ligand, CD40L, leads to the aggregation of CD40 molecules, which in turn interact with
cytoplasmic components to initiate signaling pathways. Early studies on the CD40-CD40L system
revealed its role in humoral immunity. Interaction between CD40L on T cells and CD40 on B cells
stimulated B cell proliferation and provided the signal for immunoglobulin isotype switching.
Mutations in the CD40 L gene, which resulted in a CD40L molecule unable to interact with
CD40, are responsible for the hyper-IgM syndrome. Cross-linking of CD40 with antibodies or by
binding to CD40L produces cell type-specific responses which include costimulation and
induction of proliferation, induction of cytokine production, rescue from apoptosis, and
up-regulation of adhesion molecules. Some of the early events of intracellular signaling by the
CD40-CD40L system include the association of the CD40 with TRAFs and the activation of various
kinases.
原厂资料:
CD40 is a type I transmembrane glycoprotein belonging to the TNF receptor superfamily. The
mature mCD40 consists of a 172 amino acid (aa) extracellular domain, a 22 aa transmembrane
region and a 90 aa cytoplasmic domain. CD40 is expressed on B cells, follicular dendritic cells,
dendritic cells, activated monocytes, macrophages, endothelial cells, vascular smooth muscle
cells and several tumor cell lines. The extracellular domain has the cysteinerich repeat regions,
which are characteristic for many of the receptors of the TNF superfamily. Interaction of CD40
with its ligand, CD40L, leads to the aggregation of CD40 molecules, which in turn interact with
cytoplasmic components to initiate signaling pathways. Early studies on the CD40-CD40L system
revealed its role in humoral immunity. Interaction between CD40L on T cells and CD40 on B cells
stimulated B cell proliferation and provided the signal for immunoglobulin isotype switching.
Mutations in the CD40 L gene, which resulted in a CD40L molecule unable to interact with
CD40, are responsible for the hyper-IgM syndrome. Cross-linking of CD40 with antibodies or by
binding to CD40L produces cell type-specific responses which include costimulation and
induction of proliferation, induction of cytokine production, rescue from apoptosis, and
up-regulation of adhesion molecules. Some of the early events of intracellular signaling by the
CD40-CD40L system include the association of the CD40 with TRAFs and the activation of various
kinases.