What is Immunology?
Immunology is the study of the immune system, which protects us from infection. There are three main ways in which the immune system contributes to disease. 1. Activation: The immune system may be active when fighting infections and mounting an immune response, and this results in fever, inflammation and eventual removal of the offending pathogen. It also results in the immune system retaining a very good memory of that pathogen which enables the immune system to mount a rapid and even more effective response to that pathogen should it decide to infect again.
2. Immunodeficiency: The immune system may be functioning poorly (immunodeficiency) which makes us less able to fight off infections. Immunodeficiency can occur because a component of the immune system is missing or because other factors are stopping it from working properly e.g. cancer, drugs and HIV infection.
3. Hypersensitivity: The immune system may be inappropriately active (hypersensitive) against the normal body (autoimmunity) or against harmless substances (allergy). Autoimmunity includes diseases such as rheumatoid arthritis, systemic lupus erythematosis and coeliac disease. Allergy includes conditions such as asthma, hayfever and anaphylaxis. Alternatively the immune system may become inappropriately active against harmless substances resulting in allergy e.g. asthma, hayfever and anaphylaxis.
Immune deficiency: Online Mendelian Inheritance in Man (OMIM) website