Immune system or the use of immunosuppressive medication. In contrast, autoimmunity results from a hyperactive immune system attacking normal tissues as if they were foreign organisms. Common autoimmune diseases include Hashimoto's thyroiditis, rheumatoid arthritis, diabetes mellitus type 1, and systemic lupus erythematosus. Immunology covers the study of all aspects of the immune system. Immunology is a science that examines the structure and function of the immune system. It originates from medicine and early studies on the causes of immunity to disease. The earliest known reference to immunity was during the plague of Athens in 430 BC. Thucydides noted that people who had
Adaptive immune system HIV. The fusion proteins were a way to spread the infection to other cells by simply merging them with the infected one (HIV does this too). It is believed that the ancestors of modern viviparous mammals evolved after an infection by this virus, enabling the fetus to survive the immune system of the mother. The human genome project found several thousand ERVs classified into 24 families. A theoretical framework explaining the workings of the acquired immune system is provided by immune network theory, based on interactions between idiotypes (unique molecular features of one clonotype, i.e. the unique set of antigenic