Clonal anergy

Anergy as the lack of response to an antigen by shutting down the immune response is known in the immunology. The anergy is one of the mechanisms by which prevents the immune system that T- cells attack the body's own tissues. Anergy is a permanent property. An anergic T cell is not re-activated under normal conditions. In some systems, however, by interleukin- 2, a cell anergic be reactivated.

During maturation of T-cells in the thymus develop normally many so-called auto-reactive cells. These are cells, the body's own antigens not recognized as such, and therefore the body's own tissue would attack. Most of these cells are killed or in the thymus, but few autoreactive T- cells to enter the body periphery. Detects a T- cell, whether autoreactive or not, now in the periphery of an antigen, as is their activation also depends on the presence of co-stimulatory molecules such as B7 -1 or B7 -2. Receives the T- cell recognition of an antigen on any co-stimulatory signals, it switches to the permanent state of anergy.

Pathogens that manage to attenuate the immune response against itself, can thus produce anergy. The immune system can be selectively disabled, and the pathogens no longer be attacked.

• Immunology