Responding to Threats
It takes a while for the body to develop and implement a specific immune
response. In contrast, the generalized immune response occurs immediately
whenever your health is threatened.
Generalized immune response
The immune system responds immediately when your body encounters any threat,
such as a virus or injury. In response to such threats, the immune system
produces a generalized, non-specific reaction known as inflammation. This
response is like an army artillery attack: Shells burst all over, damaging and
killing all varieties of bacteria, viruses, and other microorganisms that happen
to be in range—including some of the body's own cells.
Key cells involved in this reaction include the white blood cells, macrophages,
and neutrophils, which produce powerful destructive chemicals known as free
radicals.
Free radicals
In the presence of cancer or the invasion of a dangerous microorganism, your
body quickly produces these highly reactive and unstable warrior molecules to
take quick action against the enemy germ or physical insult. You can blame free
radicals and other elements in the generalized defensive response for the
swelling, redness, heat, and pain collectively known as inflammation. Because
they are non-specific, free radicals cause the same damage to harmful bacteria
as they do to healthy cells, if those healthy cells happen to be in their way.
After the free radicals finish their work, they're turned off, and are converted
into non-reactive, harmless molecules. Antioxidant vitamins are essential to
this conversion process, which is why you hear a lot about free radicals and the
antioxidant vitamins A, C, D, and E.
Specific immune response
As the immune response continues, it becomes more specific. White cells of the
blood and immune tissues, called lymphocytes, produce proteins called antibodies
that selectively kill the intruding organisms. This leaves other cells of the
body undamaged. In addition, your body stores and remembers the "recipe" for the
specific antibody concoction created to destroy particular intruders, allowing
for a quicker immune response to a similar threat in the future.
