Predominant T-H2-like bronchoalveolar T-lymphocyte population in atopic asthma

Analysis of fluid obtained from the lungs of asthma patients showed that T lymphocytes in their lungs were producing chemicals associated with immediate hypersensitivity. Bronchoalveolar lavage was used to retrieve lung cells from 15 asthma patients and 10 healthy individuals (the controls). The cells were tested for the presence of interleukin-2, interleukin-3, interleukin-4, interleukin-5, granulocyte-macrophage colony-stimulating factor (GM-CSF) and interferon gamma. The asthma patients had significantly higher levels of the interleukins and GM-CSF in their lungs compared with the controls. Levels of interferon gamma in the lungs of asthma patients were similar to those in the controls. This indicates that asthma involves a subset of T lymphocytes - called T-H2 - that are involved in immediate hypersensitivity.