In: Anatomy and Physiology
Vaccines are the new methodology used by the medical science field to make us immune against a variety of new pathogens which were one of the seriously faced problems in the past. In vaccines we inject heat killed pathogens to our body. Heat killed pathogens won't attack our cell. But they are able to produce antibodies in our body. Once we inject a heat killed pathogen it is identified by our immune cells as a pathogen and the immune cells react to it by producing antibodies. So the antibodies present in our bodies keeps in circulation. So in future if our body is infected with the live strain of this pathogen the antibodies in our body is ready to attack and destroy the pathogen so fast. The B cells our our immune system is responsible for that. The B cells of the system produce antibodies against specific epitopes. The B cell identifies the pathogen and makes complex with it. This complex formation will lead to the direct activation to produce immunoglobulins for the production of antibodies. The antigen then binds to the antigen binding sites of the antibody and gets destroyed there itself. So these circulating antibodies identify the live pathogen when it enters and destroy it at the moment when it comes to contact with it.