BACKGROUND: An understanding of the mechanisms responsible for the development and maintenance of allergic inflammation and their clinical implications is needed to develop specific and successful treatment for allergy.
OBJECTIVES: To characterize in vitro T-cell responses to Der p 2, one of the major allergens of house dust mite (HDM), and investigate potential correlations between clinical and laboratory parameters.
METHODS: Forty-two patients monosensitized to HDM and 10 age-matched, healthy children were studied. Dendritic cells pulsed with Der p 2 were used to stimulate autologous CD14(-) cells. Der p 2-specific T-cell activation markers, proliferation, and cytokine production profiles were examined.
RESULTS: Der p 2-specific T-cell activation markers, proliferation, and T(H)2 cytokine production were significantly higher in HDM patients compared with healthy controls. Moreover, a significant correlation between proliferation and T(H)2 cytokine production was observed. Within the allergic group, skin reaction to HDM was significantly stronger in patients with a Der p 2-specific T-cell response. Levels of HDM-specific IgE directly correlated with interleukin 5 and interleukin 13 levels and with skin prick test results and, ultimately, with the patient's family history of allergy. Furthermore, the presence of atopic march correlated with T-cell proliferation.
CONCLUSION: We found that, in HDM patients, Der p 2-specific T(H)2 responses, promoted by autologous dendritic cells in vitro, correlate with clinical parameters.