Cross talk between Trappin-2 and IL-9: clinical relevance in allergic diseases

CARO FIORELLA; AMBROSI NELLA; TATEOSIAN NANCY; LANCARFONI MARCELA; THWAITES A; PICOLLO M; VILLALONGA XIMENA; GUERRIERI DIEGO; GARCIA VERONICA; CHULUYAN EDUARDO

MAR DEL PLATA

Congreso; LXIV REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INMUNOLOGÍA; 2016

Mucosal homeostasis is maintained by the secretion of several factors. Among them, IL-9 and Trappin-2 has been described to be produced in steady state and under inflammatory condition. The aim of the present study was to determine a putative link between IL-9 and Trappin-2 in allergic female patients. For this, a sandwich ELISA was performed for IL-9 and Trappin-2 in the plasma of 19 patients (15-49 years). First we found an indirect correlation between IL-9 and the age of the patients (r = - 0.39, p = 0.008). Furthermore, a direct correlation was observed between IL-9 and Trappin-2 in the plasma of the patients (r = 0.43, p = 0.03). In order to verify that IL-9 is able to stimulate Trappin-2, the alveolar epithelial cell line A549 was treated in vitro with different concentration of IL-9 (0.1-10 ng/ml). After 24 and 48 hours, A549 cell culture supernatant was harvested and Trappin-2 was measured in it. We observed that IL-9 (1 and 10 ng/ml) was able to increase Trappin-2 in a dose and time dependent manner (p < 0.03 and p < 0.04, respectively). Following, the effect of Trappin-2 on the production of IL-9 was assessed by treating peripheral blood mononuclear cells with 5 ng/ml of Trappin-2 for 24 and 48 hs of culture. Then, cells were recovered and IL-9 was measured by intracellular staining on CD4+, CD4-, CD14+ and CD19+ cells with a flow cytometer. The analysis showed that Trappin-2 increased the staining of IL-9 on CD4+, CD4- and CD19+ but not on CD14+ cells by at least 50 %. Overall these results confirm a positive feedback between Trappin-2 and IL-9 and suggest that could be functional in female allergic patients.