Refers to a composition comprising a Strain of Bacteroides thetaiotaomicron and a pharmaceutically acceptable excipient, vehicle or diluent. It also refers to a Nutritional supplement that includes such a Strain. Said composition is useful in the treatment to reduce inflammation of tissue or organ, to treat an allergic Disorder, among othersSe refiere a una composicion que comprende a una cepa de Bacteroides thetaiotaomicron y un excipiente, vehiculo o diluyente farmaceuticamente aceptable. Tambien se refiere a un complemento nutricional que comprende dicha cepa. Dicha composicion es util en el tratamiento para reducir la inflamacion de un tejido o un organo, tratar un trastorno alergico, entre otros