Background: T cells are important cellular components of bronchial inflammation in diffuse panbronchiolitis (DPB). beta-Chemokines such as RANTES (regulated on activation, normal T-cell expressed and secreted) and macrophage inflammatory peptide (MIP)-1alpha are closely related to the migration of inflammatory cells into the lung. In this study, we investigate the contribution of beta-chemokines to the accumulation of T cells in the lungs of patients with DPB.
Patients and methods: We determined the levels of beta-chemokines in BAL fluid (BALF) and the correlation between these levels and T-cell subsets in BALF of 23 patients with DPB and 16 healthy subjects by sandwich enzyme-linked immunosorbent assay and flow cytometry.
Results: Percentages of CD3+ human leukocyte antigen (HLA)-DR+, CD8+, and CD8+HLA-DR+ cells in BALF of patients were significantly higher than in the control BALF. The absolute number of CD8+HLA-DR+ cells was also higher in BALF of patients than in the control BALF (p < 0.0001). Phenotypic analysis of CD4+ cells in BALF showed a similar percentage of CD4+CD45RA+ cells and CD4+CD29+ cells in patients and normal subjects. The concentrations of RANTES and MIP-1alpha in BALF of patients with DPB were significantly higher than in BALF of normal subjects (p < 0.05). In addition, there was a significant correlation between the absolute number or percentage of CD8+HLA-DR+ cells and MIP-1alpha concentration in BALF.
Conclusions: Our results suggest that the interaction between activated CD8+ T cells and MIP-1alpha may contribute to the pathogenesis of DPB.