Interferon-λ mediates oral tolerance and inhibits antigen-specific, T-helper 2 cell-mediated inflammation in mouse intestine.

BACKGROUND & AIMS: Oral tolerance is an important component of gastrointestinal homeostasis, but mechanisms of its development are not fully understood. Loss of oral tolerance occurs during food allergen-related inflammation in the gastrointestinal tract. Interferon (IFN)-λ regulates immunity, but its role in oral tolerance is not clear. We investigated the role and the mechanism of IFN-λ in the development of oral tolerance and its effect on antigen-induced, T-helper (Th)-2 cell-mediated inflammation in the intestine. METHODS: Expression of IFN-λ and its receptor were analyzed by immunohistochemical, flow cytometric, or immunoblot analyses. Tolerogenic dendritic cells (DCs) and regulatory T cells were examined in vitro and in vivo. A mouse model of antigen-induced, Th2 cell-mediated intestinal inflammation was used to examine the role of IFN-λ and T cells in oral tolerance in the intestine. RESULTS: CD3+ cells expressed the IFN-λ receptor, which was up-regulated following antigen-specific or nonspecific activation. Interaction between IFN-λ and its receptor induced apoptosis of T cells and their subsequent phagocytosis by DCs. This led to the generation of tolerogenic DCs and T regulatory cells in vitro and in vivo. Passive transfer of IFN-λ-primed CD3+ cells inhibited Th2 cell-mediated inflammation in the intestine. CONCLUSIONS: IFN-λ is involved in development and maintenance of oral tolerance in the intestines of mice; it might be used to suppress antigen-specific Th2 cell-mediated inflammation in patients.

A prospective randomized clinical trial comparing nepafenac, intravitreal triamcinolone and no adjuvant therapy for epiretinal membrane.

PURPOSE: To compare the efficacy of topical nepafenac 0.1% versus intravitreal triamcinolone acetonide (IVTA) at the conclusion of vitrectomy surgery versus no adjuvant therapy (NAT) in improving macular morphology post-operatively in patients undergoing vitrectomy for epiretinal membrane (ERM), as measured by optical coherence tomography (OCT) imaging and best-corrected visual acuity (BCVA). METHODS: Design: Prospective randomized clinical trial Setting: Multi-centre 80 patients scheduled to undergo vitrectomy surgery for idiopathic ERM were randomized to receive either IVTA (4 mg/0.1 cc) at the end of surgery, topical nepafenac sodium 0.1% TID for 1 month post-operation or no adjuvant treatment (NAT). Optical coherence tomography (OCT) imaging, best-corrected visual acuity and intraocular pressure (IOP) were measured before surgery, and 1 and 2 months post-operation. RESULTS: Although all three groups showed reduction in macular thickness post-operation, the NAT group showed the most improvement, with a reduction of 136.18 ± 29.84 µm at two months. There was no statistically significant difference in macular thickness between the groups at each time point, p = 0.158. The NAT group also had the best recovery in BCVA with an improvement of 0.207 logMAR (10.35 letters) at two months post-operation. There was no statistically significant difference in BCVA between the groups, p = 0.606. There was statistically significant difference in the IOP between the three groups, p = 0.04 only at 1-month visit. The IVTA group had the highest rise in average IOP at both 1 and 2 months post-operation (2.72 and 1.58 mmHg, respectively). CONCLUSION: Our study data suggest there was no advantage in the use of topical nepafenac or IVTA for post-vitrectomy ERM surgery.