Cytokine mRNA profile and cell activation in bronchoalveolar lavage fluid from nonatopic patients with symptomatic asthma.

Recent studies have indicated that airway inflammation in atopic asthma is characterized by T-cell activation and local eosinophilia, but it is unknown whether this also applies to nonatopic asthma. In this study, the cytokine mRNA profile and activation status of inflammatory cells in bronchoalveolar lavage fluid (BALF) of eight nonallergic patients with symptomatic asthma and eight nonallergic healthy controls were compared using the message amplification phenotyping (MAPPing) with the polymerase chain reaction (PCR) procedure and immunocytochemical evaluation. Asthmatics had an increasing number of inflammatory cells in BALF, including activated eosinophils (EG2-positive) (p less than 0.001) and activated T cells (CD25-positive) (p less than 0.001). Activated T cells from five of the eight asthmatic patients and from one control subject expressed high levels of interleukin 5 (IL-5) and granulocyte-macrophage colony-stimulating factor (GM-CSF). All the asthmatic patients had increased numbers of monocytes in their BALF (p less than 0.002) and those cells invariably showed increased expression of interleukin 1 beta (IL1 beta) transcripts. In five patients they also expressed appreciable levels of IL-6 and GM-CSF mRNA. IL-5 and GM-CSF can induce local activation of eosinophils, and IL-1 beta and IL-6 are known to promote T-cell activation and proliferation. Thus, there is an increased production of cytokines with inflammatory properties in the airways of patients with nonatopic symptomatic asthma, which may contribute to the persistence of inflammation, and monocytes and activated T cells are important sources of these cytokines.