Abstract
Purpose:
Recently studies performed on beta-1,3-D-glucan, a cell wall component of a variety of fungi, yeasts, and bacteria, demonstrated that it affects the balance of Th1/Th2 immune response. We therefore determined whether topical application of beta-1,3-D-glucan modulates ocular allergy in murine model.
Methods:
7-8 week-old BALB/c mice were sensitized via intraperitoneal injection once with Ovalbumin (OVA) and aluminum hydroxide. Mice were rested for 2 weeks and then challenged by instillation of OVA eyedrops once daily for 13 days. beta-1,3-D-glucan (BG) eyedrop was administered 5 min after OVA challenge once daily. Clinical signs were measured and we evaluated the infiltration of eosinophils and mast cells into conjunctiva with flow cytometry, and serum levels of OVA specific IgE production and Th2 cytokines in vitro stimulation of T cell in drainage lymph nodes (LN)
Results:
BG treated mice showed less allergic conjunctivitis, indicated by clinical signs and decreased production of serum OVA specific IgE. In addition, BG treatment led to decreased infiltrations of CD45 positive immune cells, eosinophil, and mast cells into conjunctiva, compare to only vehicle treated (control) mice. BG administration suppressed Th2 cytokine production in vitro T cells assay through the induction of IL-10 producing CD4 T cells in drainage LNs
Conclusions:
Taken together, these results suggest that beta-1,3-D-glucan is capable of inducing IL-10-producing CD4+ T cells and suppressing the Th2 response in drainage LNs and conjunctival eosinophil infiltration, as the therapeutic potential of topical beta-1,3-D-glucan for allergic conjunctivitis.