Effect of recombinant interleukin-2 on peripheral blood mononuclear cells following antigen-specific bronchial provocation.

In a group of 18 patients with seasonal asthma and rhinitis acute bronchial provocation was performed with grass pollen antigens. Blood samples were taken before and 15 minutes after the maximal clinical response. Effect of recombinant interleukin-2 (IL-2) on peripheral blood mononuclear cells (PBMCs) by tritiated thymidine uptake method was investigated. T4 and T8 subpopulations were also evaluated before and after acute challenge. The patients had a significantly higher responsiveness of their PBMCs to IL-2 in vitro. After acute challenge there was a significant reduction of the IL-2 responsiveness as well as a decrease in percentage of T4 cells. These changes, however, poorly correlated with the degree of bronchial obstruction and with the dose of inhaled antigen.