Archive for December 7th, 2009

Cellular Mediated Immunity

Ok so today you are getting a little more than the introduction… arent you lucky! But the premise is still the same, to view/download/print this article, please head to! Apart from that, id like to present: Cellular Mediated immunity! (Or at least 1 of the 6 pages)


The two major components of the adaptive immune system are known as cellular and humoral immunity. For an effective immune system these two branches of the adaptive immune system must interact. The main effector cells of these two systems are the T and B-lymphocytes.

T and B-lymphocytes both develop from a common progenitor in the bone marrow. T cells then move on to fully develop in the thymus and B cells develop in the bone marrow (in the foetus they develop in the liver). Any T or B cells that are at rest are morphologically indistinguishable.

Both T and C cells are able to recognise and bind an antigen and show a specific memory. B cells recognise antigens with the surface membrane Ig – which determines the specificity of the cell. T cells recognise the antigen with the T cell receptor which has both variable and hypervariable regions similar to yet still distinct from those of the immunoglobulin molecules.

Stimulation of a T cell by a specific antigen leads to the generation of effector T cells, which may directly and specifically kill cells bearing the appropriate antigen (or have other protective effects)

T and B cells can be distinguished by; their surface cells markers or their antigens. Many of these have a functional role e.g. CD8 are T Cytotoxic cells.