What is the Common Receptors Present on T cells?

Erythrocyte receptors (E receptors):

These receptors help in distinguishing T cells from B cells. For unknown reasons the T cells of man and other animal T cells processes this polypeptide receptors.

This helps in the formation of rosettes of foreign erythrocytes. Their physiological role is. Probably that of a negative signal receptor.

Compliment receptors:

T cells process receptors for activated components of compliment system, that probably expressed after activation followed by antigen interaction.

4) la Protein Receptor:

This receptor recognizes immune associated proteins (la proteins) and help in coordination with B cell and macrophages.

Histamine receptor (H2):

T cells process H2 histamine receptors. They help in regulation of T cell activity. Binding of histamine with this receptor reduces T cell activity.

IL-1 and IL-2 receptors:

The IL-1 interleukin produced by macrophages combine with IL-1 receptor to initiate T cell response. The IL-2 interleukin secreted by activated T cells binds again to IL-2 receptor of the T cell for autocrine and paracrine signaling to the T cells.

Ti Receptor:

It is a basic antigen receptor with two transmembrane glycoprotein chains a (50 kD) and p (45 kD) joined by disulphide bond. In certain situations the Ti may have a third y chain of 55kD. y8 heterodimer is expressed on about 5% of cells. TCR with y5 are known as TCR1 and TCR with a(3 glycoproteins are known as TCR2 receptors.

CD3 receptor:

It is a non covalent complex of 3 types of chains y (25 kD) y 5 (20 kD) and s (20 kD). All the three chains are essential for T cell function, CD, peptide chains are involved in signal transduction after interaction with antibody. CD3 with TCR produces the TCR CD3 complex an “ion channel” for the entry of Ca+ into the T cell.

CD4marker:

This marker is found on T helper cells. It is a 60 kD glycoprotein and is involved in interaction of the T cell with MHC class II molecules of antigen presenting cells (APC). This acts as a receptor for HJV virus.

HIV CD4 marker:

It is a glycoprotein marker formed on Tc and Ts cells. It is involved in interaction of the Tc cells with class I molecules present on infected cells or Tumour cells.