Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Critical Care giúp cho các bạn có thêm kiến thức về ngành y học đề tài: Effect of anti-IgE therapy on food allergen specific T cell responses in eosinophil associated gastrointestinal disorders. | Foster et al. Clinical and Molecular Allergy 2011 9 7 http content 9 1 7 RESEARCH CMA CLINICAL AND MOLECULAR ALLERGY Open Access Effect of anti-IgE therapy on food allergen specific T cell responses in eosinophil associated gastrointestinal disorders Barbara Foster Shabnam Foroughi Yuzhi Yin and Caiman Prussin Abstract Background Anti-IgE therapy inhibits mast cell and basophil activation blocks IgE binding to both FceRI and CD23 and down regulates FceRI expression by antigen Ag presenting cells APCs . In addition to its classical role in immediate hypersensitivity IgE has been shown in vitro to facilitate Ag presentation of allergens whereby APC bound IgE preferentially takes up allergens for subsequent processing and presentation. The purpose of this study was to determine whether anti-IgE therapy by blocking facilitated Ag presentation in vivo attenuates allergen specific Th2 cell responses. Methods To test this hypothesis food allergen specific T cell responses were examined during a 16-week clinical trial of omalizumab in nine subjects with eosinophilic gastroenteritis and food sensitization. Allergen specific T cell responses were measured using carboxyfluorescein succinimidyl ester dye dilution coupled with intracellular cytokine staining and polychromatic flow cytometry. Four independent indices of allergen specific T cell response proliferation Ag dose response precursor frequency and the ratio of Th2 Th1 cytokine expression were determined. Results Eight of the 9 subjects had measurable food allergen specific responses with a median proliferation index of 112-fold. Allergen specific T cell proliferation was limited to CD4 T cells whereas CD8 T cell did not proliferate. Food allergen specific responses were Th2 skewed relative to tetanus specific responses in the same subjects. In contradistinction to the original hypothesis anti-IgE treatment did not diminish any of the four measured indices of allergen specific T cell .
