Pathology caused by the cellmediated immune response

The mere expression of a cell-mediated immune response involves some degree of inflammation, lymphocyte infiltration, macrophage accumulation and activation and can therefore by itself cause pathological changes. This type of response predominates in the pathogenesis of tuberculosis, with mononuclear cell infiltration, degeneration of parasitised macrophages, and the formation of giant cells as central features. In chronic mycobacterial infection, the continuous release of microbial antigens...

Classification of autoimmune disease

In the 1950s, Witebsky established the criteria for determining the aetiology of human diseases which were thought to be autoimmune. Witebsky's postulates were modelled on those of Koch and required the presence of autoantibody or a cell-mediated immune response to a self-antigen, which having been identified, could induce a similar disease in an experimental host mediated by the same immunological mechanism. Since these criteria were established, our knowledge of immunology has increased by...

Physical carcinogens

The discovery and subsequent use of X-rays and radioactivity in the late 19th century resulted in the first examples of cancer caused by physical carcinogens. In more recent years, the most convincing evidence of radiation-induced carcinogenesis has come from studies of the survivors of the Hiroshima atomic bomb and the population who lived in the vicinity of the Chernobyl atomic energy plant. These people have presented with increased incidences of a range of tumours usually several years...

Which of the following statements concerning autoimmunity is Correct

a Autoimmunity is vital to the development of a normal immune response. b T cells only recognise and respond to antigen when it is processed and presented in association with foreign MHC gene products. c Autoimmune disease arises as a result of the development of self-tolerance. d Autoimmunity may develop as a result of exposure in adult life to an antigen which was hidden from the immune system in the early stages ofdevelopment. e Self-tolerance develops within the first 6 months of life.