What is CD28 and what is it for?

What is CD28 and what is it for?

Furthermore, CD28 was also identified on bone marrow stromal cells, plasma cells, neutrophils and eosinophils, but the functional importance of CD28 on these cells is not completely understood.

What is the difference between CD28 and CD86?

The CD86 expression on antigen-presenting cells is constitutive (expression is independent of environmental factors). CD28 is the only B7 receptor constitutively expressed on naive T cells. Association of the TCR of a naive T cell with MHC: antigen complex without CD28:B7 interaction results in a T cell that is anergic .

Is CD28 a B7 receptor?

CD28 is the only B7 receptor constitutively expressed on naive T cells. Association of the TCR of a naive T cell with MHC: antigen complex without CD28:B7 interaction results in a T cell that is anergic. CD28 is also expressed on 50 % of CD8+ T cells and more than 90 % CD4+ T cells in human.

What percentage of human T cells contain CD28?

It is generally reported, that CD28 is expressed on 50 % of CD8+ T cells and more than 80 % CD4+ T cells in human, but during the course of activation some T cells lose this molecule. Some antigen-experienced T cells lose CD28 and subsequently can be re-activated without CD28 engagement.

What is the cd28-cd80 complex?

In the CD28-CD80 complex, the two CD80 molecules converge such that their membrane proximal domains collide sterically, despite the availability of both ligand binding sites for CD28. CD28 belongs into group members of a subfamily of costimulatory molecules that are characterized by an extracellular variable immunoglobulin-like domain.

What is the function of CD28 as a homodimer of two chains?

As a homodimer of two chains with Ig domains binds B7 molecules on APCs and it can promotes T cells proliferation and differentiation, stimulates production of growth factors and induces the expression of anti-apoptotic proteins. According to several studies, after birth, all human cells express CD28.