Immune memory lead to the efficacy of vaccines

Question

How can the immune memory lead to the efficacy of vaccines and also bring into being allergies?

Answer 1

Vaccines are managed inoculations of pieces of fragments of infectious agents or of inactive infectious agents to make the initial immune reaction, the formation of particular memory B-lymphocytes in opposition to the antigen. So the organism geenrates immunoglobulins and becomes ready to destroy antigens while exposed to new infections by that agents.

In allergies the humoral immune system is sensitized (creates antibodies and particular memory B lymphocytes) in opposition to some ordinary environmental substances wrongly known as antigens. e.g., pollen-derived substances, dust element, complexes present in foods or in medication, etc. can be identified as antigens triggering the intial response and creating an immune remembrance against them which then become reason of allergy. The greater the individual is exposed to those materials the greater intense is the immune response.  The IgE antibodies that cause allergic reaction bind to receptors of leukocytes known as mastocytes whose cytoplasm is fully histamine granules. The antibodymastocyte bond is responsible for these cells to discharge a great quantity of histamine in the circulation, stimulating inflammation and producing the allergic indications and signs. For this motive allergy is handled with antihistamines, medicines that restrict the histaminic response.  Exacerbated allergic reactions, e.g., in hypersensitivity to a number of medicines such as penicillin and sulfas, can cause anaphylactic shock, an insensitive clinical condition that occasionally leads to death.