The immune system immune system
Cells, cell products, organs, and structures of the body involved in the detection and destruction of foreign invaders, such as bacteria, viruses, and cancer cells. Immunity is based on the system's ability to launch a defense against such invaders. somehow manages to turn itself off after fighting an infection. Research by David S. Strayer of the University of Texas in Houston indicates that viruses use the same "off" mechanism to dodge the immune system, and that the immune system in turn can eventually counter the ploy.
Strayer's work, presented at the Sixth International Congress of Immunology earlier this month in Toronto, fits into an idea gaining a foothold in immunology -- that the immune system actively inhibits its own suppressive sup·pres·sive
Tending or serving to suppress.
Adj. 1. suppressive - tending to suppress; "the government used suppressive measures to control the protest" response, turning itself back on after it has turned itself off. The process is known as contrasuppression. Proponents of the theory believe overambitious o·ver·am·bi·tious
Ambitious to an excessive degree.
over·am·bi contrasuppression causes the immune system to attack itself in autoimmune diseases Autoimmune diseases
A group of diseases, like rheumatoid arthritis and systemic lupus erythematosus, in which immune cells turn on the body, attacking various tissues and organs.
Mentioned in: Complement Deficiencies, Premature Menopause .
Strayer infected rabbits with a virus and looked at their immune-cell-harboring spleens. In the test tube, spleen cells collected 7 days after infection were capable of only a low response to immune stimulators, but spleen cells collected 11 days after infection were better able to respond. The liquid portion of the 7-day cell culture, but not from the 11-day cells, contained a substance that suppressed other immune cells.
The virus, Strayer suggests, activates the natural suppression of the immune system, causing the 7-day cells to produce and secrete secrete /se·crete/ (se-kret´) to elaborate and release a secretion.
To generate and separate a substance from cells or bodily fluids. a substnace that suppresses the immune response immune response
An integrated bodily response to an antigen, especially one mediated by lymphocytes and involving recognition of antigens by specific antibodies or previously sensitized lymphocytes. . By day 11, the rabbits' immune systems were suppressing the virus-induced suppression.