The influence of interleukin 15 on the expression of CD30 and OX40 antigens in adult patients with Celiac Disease

NATALIA PERIOLO; GUILLéN L; ARRUVITO L.; VODáNOVICH F; NIVELONI SI; HWANG JH; BAI JC ; AC CHERÑAVSKY

Orlando

Congreso; Digestive Disease Week 2013; 2013

American Society of Gastroenterology

ABSTRACT BODY: Background: CD30 and OX40 are members of the nerve growth factor receptor / tumor necrosis factor receptor super family involved in co stimulation of Th1 immune responses. Interleukin (IL)-15 contributes to the pathogenesis of Celiac Disease (CD), a Th-1 mediated disease. We previously demonstrated an IL-15- induced increase of circulating CD3+CD30+ in Cel, and a similar expression of CD30 in lamina propria lymphocytes (LPL) from healthy controls (HC) and CD patients (Cel). The potential influence of IL-15 on CD30 and OX40 expression at the small intestine has not been examined. Aim: to investigate OX40 and CD30 expression at peripheral and local compartments and its potential regulation by IL-15 in CD. Patients and Methodology: 38 Cel and 38 age-matched healthy volunteers (> 18y) were included as HC. T blasts were obtained after culturing peripheral blood mononuclear cells (PBMC) for 3 days with anti-CD3 (1mg/ml). Additional 3 days incubations with RPMI- 1640 alone, recombinant IL-15 (rIL-15,50 ng/ml), or anti-IL-15 mAb (10 ng/ml) were performed. T blasts, intra epithelial lymphocytes (IEL)-containing suspensions and LPL-containing LP suspensions were incubated with conjugated anti- CD3, -CD4, -CD8, -CD25, -CD30 or -OX40 for surface staining. After surface staining T blasts were incubated with PMA (50ng/ml) / calcium ionophore (1µg/ml) / Brefeldin A (10 µg/ml) for intracellular IL-4 and INF-ã or without PMA (for FoxP3 staining). Results: circulating CD3+OX40+ cells were down regulated in HC and Cel by anti-CD3+ rIL-15 (p<0.01 vs. anti-CD3) but this was prevented by anti-CD3+anti-IL-15(p<0.01, vs. anti-CD3+ rIL-15, ANOVA with Bonferroni‘s multiple comparison post test). The addition of rIL-15 to biopsy specimens up-regulated CD3+CD30+ (but not CD3+OX40+) LPL (p<0.05, paired Student t-test) in HC and Cel. At baseline, the percentage of circulating INF-ã+ CD3+CD30+ cells is 9-folds greater in T blasts cultures from Cel (p<0.01, vs. HC, unpaired Student t- test). After IL-15 addition to T blasts, the frequency of INF-ã+ CD3+CD30+ cells increased in HC (p < 0.05, vs. RPMI alone, unpaired Student t- test). The addition of rIL-15 to T blasts also increased the frequency of OX40+ CD4+CD25+ Foxp3+ cells (defined as CD4+ T regulatory cells, Tregs) in Cel (p < 0.05 vs. RPMI, paired Student t-test)Conclusion: the down regulation of OX40 in circulating CD3+ cells and the up regulation of CD30 in duodenal LPL from all individuals are common components of the IL-15-driven innate response. Conversely, the presence of an increased subpopulation of Th1-committed CD30+ T blasts as well as the distinctively enhanced subpopulation of circulating OX40+CD4+ Tregs under the influence of IL-15 in CD reveal that CD30 and OX40 are differentially regulated by IL-15 and potentially involved in the pathogenic T cell mediated response.