Sublingual immunotherapy-induced IL-10 production is associated with changed response to the decongestion test: Preliminary results

Abstract

Sublingual immunotherapy (SLIT) has been shown to be capable of inducing a regulatory T-cell response as evidenced by IL-10 production. Decongestion testing consists of spraying an intranasal vasoconstrictor drug to evaluate the recovery of nasal airflow limitation. The aim of this study was to assess the association of SLIT-induced IL-10 production with nasal airflow recovery after decongestion testing. Nineteen patients with perennial allergic rhinitis (PAR) were studied: 9 patients successfully assumed SLIT for 3 years and 10 patients were considered as control. In vitro IL-10 production was evaluated after SLIT. Rhinomanometry and decongestion testing were performed in all subjects before and after 3 years. After 3 years, SLIT patients showed a significant decrease of nasal resistances (0.048) and reduced response to decongestion testing (p = 0.044 for absolute values and p = 0.0051 for delta). The comparison with nontreated allergic patients shows significant differences concerning both pretest values (p = 0.02) and delta percentages (p = 0.00466). In addition, the decrease of nasal airflow resistance values and the percentages of reversibility were significantly associated with IL-10 levels (p = 0.0016 and p = 0.00294, respectively). This preliminary study provides the first evidence of a changed response to decongestion testing after SLIT that is associated with IL-10 production in patients with PAR.