I believe that the cellular part of the immune system has developed originally as a surveillance mechanism for cancer cells. In the course of our life, our bodies develop a slightly refined system for recognizing subtle distinctions between self and non-self.
That is why the rejection of a transplant is the price we pay for possessing such an efficient system of surveillance. If a surgeon transplants a patch of skin from one part of a patient’s body to another part, the graft is usually accepted as self. But if a surgeon attempts to transplant skin for brother to sister, the borrowed tissue grows puffy, inflamed, and irritated. Eventually it drops off. Even though the donor and recipient are blood related, the graft is rejected as foreign by the innate intelligence of the body.
Amazing isn’t it?
20/20 VISION — SEEING YOUR POSSIBILITIES