Abstract 1833 Berberine Inhibits Tonsil B Cell IgE Production Following IL-4/Anti-CD40 Stimulation

Objective: Berberine (BBR), a natural plant isoquinoline alkaloid, has previously been shown to suppress IgE production in vitro by human myeloma cells (U266) in a dose-dependent manner as well as inhibit IgE production by peripheral blood mononuclear cells. We hypothesized that berberine may suppress IgE production by activated B cells derived from human tonsils. Methods: Eleven patients aged 6 to 25 years undergoing tonsillectomy at the Westchester Medical Center were recruited for the study after obtaining informed consent. Surgically removed tonsil samples were homogenized using DNase and collagenase to obtain single-cell suspensions. Cells (4x106/mL) were stimulated with human anti-CD40 and IL-4 in the presence or absence of BBR at concentrations of 10 μg/mL or 20 μg/mL for 10 days. Cell supernatants were harvested, and IgE levels were determined by ELISA. Results: All patients were diagnosed with chronic tonsillitis, tonsillar hypertrophy, and/or obstructive sleep apnea. Cell culture supernatant IgE levels were significantly reduced by BBR treatments at both 10 μg/mL (p<0.001) and 20 μg/mL (p<0.001) as compared to untreated controls, without any associated cell cytotoxicity. Conclusions: The inhibitory effect of berberine on IgE levels in anti-CD40/IL-4 stimulated human tonsil cells suggests promising directions for investigating molecular mechanisms associated with IgE inhibition.