Isnt it true that the body has a natural defense system that enables it to combat infection and other abnormal substances? Why isnt this system able to fight cancer cells? Lourdes P. Manila
Youre right, the body has a defense system against invading microorganisms and foreign substances. In fact, this system is two pronged: non-immune and immune. The non-immune system is otherwise known as inflammation, a complex, localized response process that also plays a role in the
subsequent activation of the immune system. It is an immediate response that starts within minutes of entry of an offending substance.
The immune defense system, on the other hand, is characterized by an antigen-specific response to a foreign substance (microorganism or antigen) that takes several days to develop. A key feature of the immune defense system is memory of the offending substance so that subsequent exposure of the body to the substance elicits a more rapid and vigorous response.
The cells of the two defense systems are widely distributed all over the body. They destroy not only bacteria and foreign substances, but also dead or dying cells and tissue elements that need to be disposed off. They likewise destroy abnormal cells including cancer cells, but obviously they are not able to completely eliminate all cancer cells, otherwise, cancer will not exist as a disease entity.
Cancer cells are abnormal cells that multiply rapidly. The cells of the bodys defense system are able to recognize most cancer cells as foreign cells. …