IMMUNOLOGY

Detailed explanation-1: -An antigen specifically induces the production of antibodies which can bind to it and neutralise it. While most vaccines work by inducing B lymphocytes to produce antibodies (see below), activation of T-cells-another type of immune system cell that helps protect against disease-is also important for some vaccines.

Detailed explanation-2: -They produce antibodies that attack the pieces of the virus left behind by the macrophages. T-lymphocytes are another type of defensive white blood cell. They attack cells in the body that have already been infected.

Detailed explanation-3: -Measles vaccine induces both humoral and cellular immune responses. Antibodies first appear between 12 and 15 days after vaccination and peak at 21–28 days.

Detailed explanation-4: -The macrophages leave behind parts of the invading germs called antigens. The body identifies antigens as dangerous and stimulates antibodies to attack them. B-lymphocytes are defensive white blood cells; they can produce antibodies to fight off infection.

Detailed explanation-5: -For example, in response to an infection or vaccination with a live virus, IgM antibodies usually are made first, followed by IgG and some other types of antibodies.

Detailed explanation-6: -MMR vaccines contain live measles, mumps and rubella viruses that have been weakened (attenuated). These stimulate the immune system but do not cause disease in healthy people.