Immunology
Without a clear understanding of immunology, it is difficult to interpret the clinical rationale and consequences of blood transfusion as well as to interpret immunohaematological tests in the laboratory.
Abstract
Immunology is the study of the immune system and how the body protects itself from infection using a variety of methods. Failure of the immune system to function correctly can result in disease, such as autoimmunity, allergy and cancer. Immunological defence is important to confer protection of an organism against invasion by foreign microorganisms and to facilitate tissue repair. The body recognises ‘self’ and targets the foreign ‘non-self’ as potentially harmful and to be destroyed. Differentiation between self and non-self, and the body’s reaction to non-self, forms the basis of the immune response. Allogeneic blood transfusion essentially introduces a foreign substance into the body. It is therefore crucial that the blood product to be infused is selected to be as immunologically compatible as practically possible, i.e. it should match ‘self’ as closely as possible to prevent undue immune reaction in the host, to the blood being transfused. An immune reaction can result in reduced clinical efficacy or have an adverse effect on the recipient. Without a clear understanding of immunology, it is difficult to interpret the clinical rationale and consequences of blood transfusion as well as to interpret immunohaematological tests in the laboratory.