PATHOLOGY

Detailed explanation-1: -Vaccines contain weakened or inactive parts of a particular organism (antigen) that triggers an immune response within the body. Newer vaccines contain the blueprint for producing antigens rather than the antigen itself.

Detailed explanation-2: -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-3: -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. For the most part, the antibodies that you form from getting vaccinated are the same kind of antibodies you would get from a natural infection.

Detailed explanation-4: -Vaccines contain antigens that stimulate the immune system to produce an immune response that is often similar to that produced by the natural infection.