The immune system protects the body against infections. The immune system (ih-MYOON) fights the germs and works to keep us safe.
When the body senses foreign substances (called antigens), the immune system functions to recognize and get rid of the antigens.
B lymphocytes are activated through the development of antibodies. These specialist proteins lock different antigens onto them. The antibodies linger in an individual’s body. Thus, once the immune system detects the antigen again, the antibodies are able to do their job. That’s why someone, like chickenpox, who gets sick with a disease generally won’t get sick from that again.
This is also how certain illnesses are avoided by immunizations (vaccines). The immunization brings the antigen into the body in a manner that will not make us ill. But it does allow the body to build antibodies that will protect the individual from potential germ attack.
Such specialized cells and parts of the immune system provide the body with disease protection. This defense is known as immunity.
Generate healthy cells to replace damaged cells. Stem cells can be directed to become different cells and can be used in humans to rebuild and restore diseased or damaged tissue.