Production of interleukin-13 is influenced by the interleukin-4 -34TT and -590TT genotype in patients with aggressive periodontitis

Aggressive periodontitis (AgP) is a specific form of periodontal disease, with rapid destruction of the tissues supporting the teeth in otherwise young healthy individuals. We recently showed a higher frequency of the interleukin-4 (IL-4) -34TT and -590TT genotype in AgP patients compared to controls (P<0.05). Herein, we demonstrated that this specific IL-4 genotype exerts its function by increasing expression of IL-4 and STAT6, and producing higher concentrations of IL-4 in activated CD4+ cells of patients with AgP. In the present study, we investigated the effects of the IL-4-specific genotype on IL-13, IL-2 and IFN-γ expression and production in activated CD4+ cells of patients with AgP and healthy controls. Results revealed higher IFN-γ and IL-2 expression and significantly increased IL-13 production in the cells of the patients who were homozygous for the -34T and -590T alleles in comparison with the patients who were homozygous for the -34C and -590C alleles (P<0.05). Results of controls with the -34C and -590C alleles were similar to those of AgP with the same genotype. To our knowledge, the present study is the first to show an effect of the -34TT and -590TT genotype on IL-13 production. There is an increased production of IL-13 by the T cells of aggressive periodontitis patients with the IL-4 genotype.