Allergen-induced in vitro expression of IL-18, SLAM and GATA-3 mRNA in PBMC during sublingual immunotherapy
Article first published online: 6 JUL 2007
Volume 62, Issue 8, pages 949–953, August 2007
How to Cite
Savolainen, J., Nieminen, K., Laaksonen, K., Laiho, T., Jacobsen, L., Lahesmaa, R., Terho, E. O. and Valovirta, E. (2007), Allergen-induced in vitro expression of IL-18, SLAM and GATA-3 mRNA in PBMC during sublingual immunotherapy. Allergy, 62: 949–953. doi: 10.1111/j.1398-9995.2007.01426.x
- Issue published online: 6 JUL 2007
- Article first published online: 6 JUL 2007
- Accepted for publication 14 April 2007
- pollen allergy;
- signalling lymphocytic activation molecule;
- sublingual immunotherapy
Background: Signalling lymphocytic activation molecule (SLAM) and interleukin (IL)-18 induce interferon (IFN)-γ production from Th1 cells. The allergen-induced SLAM and IL-18 mRNA expressions are increased during subcutaneous immunotherapy (SCIT), but nothing is known about their role during sublingual immunotherapy (SLIT). Transcription factor GATA-3 is associated with Th2 cells but its role in SCIT and SLIT is yet unexplored. This study was undertaken to analyse the allergen induced in vitro mRNA expression of IL-18, SLAM and GATA-3 in peripheral blood mononuclear cells (PBMC) of children with allergic rhinitis (AR) during SLIT.
Methods: Ten patients with AR undergoing pollen SLIT with a weekly dose of 200 000 SQ-U, 10 with 24 000 SQ-U of mixture of Betula verrucosa, Corylus avellana and Alnus glutinosa and 10 with placebo were included. Peripheral blood mononuclear cell were stimulated with birch extract prior to, after 1 and 2 years of the treatment. The mRNA expression was assessed using kinetic real-time RT-PCR (TaqMan®; Applied Biosystems, Foster City, CA, USA).
Results: The expression of IL-18 mRNA was increased in the high-dose group in comparison to the placebo group after 1 year of therapy (P = 0.028) and had an inverse correlation with the late phase skin reaction after the second study year (r = −0.41, P = 0.041). SLAM mRNA expression increased in the high-dose group from baseline to 1 year (P = 0.028) and correlated with IL-10 (r = 0.96, P < 0.0001) and transforming growth factor-β (r = 0.80, P = 0.0037) mRNA expression. No significant changes were seen in GATA-3 mRNA expression.
Conclusions: During SLIT, IL-18 and SLAM are upregulated, suggesting that the Th2 type inflammatory response is downregulated during SLIT by increased Th1 type response.