Consort hypersensitivity pneumonitis

R Merget1, I Sander, S Ewig

  • 1Research Institute of Occupational Medicine, German Social Accident Insurance (BGFA), Ruhr University, Bochum, Germany. merget@bgfa.de

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Delayed-Type Hypersensitivity (DTH), or Type IV hypersensitivity, is a cell-mediated immune response. It occurs when T cells, rather than antibodies, mediate a reaction to specific antigens. It is characterized by a delayed onset (1-2 days) and involves the recruitment of macrophages to the inflammation site.The initiation of a DTH response begins with the sensitization of T cells. During this phase, which lasts at least 1-2 weeks, antigen-specific T cells are activated, clonally expanded, and...
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