Tuesday, 6 December 2011: 13:15 - 13:30
Cozumel 2 (Cancún Center)
Susanne C. Diesner
,
Medical University of Vienna, Department of Pathophysiology and Allergy Research and Department of Pedriatics and Adolescent Medicine, Vienna, Austria
Cornelia Schultz
,
Medical University of Vienna, Department of Pathophysiology and Allergy Research, Vienna, Austria
Xueyan Wang
,
University of Vienna, Department of Pharmaceutical Technology and Biopharmaceutics, Vienna, Austria
Gerda Ratzinger
,
University of Vienna, Department of Pharmaceutical Technology and Biopharmaceutics, Vienna, Austria
Philipp Starkl
,
Medical University of Vienna, Department of Pathophysiology and Allergy Research, Vienna, Austria
Vera Assmann
,
Medical University of Vienna, Department of Pathophysiology and Allergy Research, Vienna, Austria
Kristina Kreiner
,
Medical University of Vienna, Department of Pathophysiology and Allergy Research, Vienna, Austria
Franziska Roth-Walter, PhD
,
Medical University of Vienna, Department of Pathophysiology and Allergy Research, Vienna, Austria
Isabella Pali-Schöll, PhD, MSc
,
Medical University of Vienna, Department of Pathophysiology and Allergy Research, Vienna, Austria
Erika Jensen-Jarolim, MD, Prof.
,
Medical University of Vienna, Department of Pathophysiology and Allergy Research, Vienna, Austria
Franz Gabor
,
University of Vienna, Department of Pharmaceutical Technology and Biopharmaceutics, Vienna, Austria
Eva Untersmayr
,
Medical University of Vienna, Department of Pathophysiology and Allergy Research, Vienna, Austria
Background: Recently, we demonstrated in an experimental mouse study that mucosal M-cell targeting with Aleuria aurantia lectin (AAL) coated Poly(D,L-lactide-co-glycolide) (PLGA) microspheres represents a promising oral treatment approach in IgE mediated allergy. Due to its structural similarities with AAL we aimed to assess Neuraminidase (NA) from Vibrio cholerae as a novel M-cell specific targeters and compared its properties to AAL and wheat germ agglutinin (WGA) representing two plant lectins, which target either M-cells or epithelial cells, respectively.
Methods: The resistance against gastric digestion of NA, AAL and WGA was analyzed in simulated gastric fluid (SGF) experiments. Intestinal epithelial binding was determined using the colon carcinoma cell line Caco2, which represents a well established model for the human intestinal epithelium. Binding specificity was evaluated by inhibition experiments by incubating Caco2 cells with Biotin-labeled NA, AAL or WGA, after preincubation with a-L fucose, monoganglioside (GM1) or N,N’,N’’-triacetyl-chitotriose (TCT). The stimulatory effects of the targeting substances on the intestinal microenvironment were investigated by cytokine read-out experiments in real-time PCR. Further, the transeptihelial uptake of NA-, AAL- or WGA-functionalized fluospheres was evaluated in a human M-cell co-culture model.
Results: All three targeters were stable up to 180 min in SGF, indicating their suitability for oral application. The binding partners were a-L fucose for AAL and TCT for WGA, whereas NA interacts with intestinal epithelial cells via a-L fucose and additionally GM1. NA skewed the cytokine production by inducing a two fold increase of the Th1 cytokine IFNg after 60 min, whereas AAL decreased the overall cytokine expression. In a human M-cell co-culture model, a higher transepithelial transport rate of fluospheres coated with NA and AAL was observed as compared to WGA and plain particles.
Conclusions: NA specifically targets M-cells via a-L fucose and additionally GM1 and, thus, increases the transepithelial transport of NA coated particles. Due to the immunomodulatory capacity on intestinal epithelial cells, NA functionalized microspheres may represent a promising M-cell specific targeting approach for oral immunotherapy.
