Indoleamine 2,3-dioxygenase: From tolerance during pregnancy to cancer
نویسنده
چکیده
RESUMEN El feto expresa durante el embarazo antígenos procedentes del padre que no provocan el rechazo como cualquier otro injerto semi-alogénico. Entre los sistemas implicados en la inducción de la tolerancia materno-fetal, se encuentra la enzima indolamina 2,3-dioxigenasa (IDO) que inicia la degradación del triptófano. Al consumir el triptófano provoca una inhibición de la respuesta de las células T que no pueden superar un punto de control de la fase G1 del ciclo celular. Numerosos tumores pueden expresar la enzima IDO de forma ectópica con lo que evitan el ataque inmune. También las células dendríticas pueden expresar actividad IDO, con lo que pueden inducir una respuesta tolerogénica. La enzima IDO puede ser una nueva diana inmunoterapéutica, ya que sus inhibidores pueden hacer más lento el crecimiento tumoral, y su administración conjunta con quimioterápicos produce una regresión tumoral. El entendimiento de esta capacidad tolerogénica del tumor ayuda no sólo a comprender el cáncer sino también a desarrollar nuevos enfoques terapeúticos
منابع مشابه
Indoleamine 2,3-Dioxygenase and Immunological Tolerance during Pregnancy
Indoleamine 2,3-dioxygenase (IDO), an enzyme involved in the catabolism of tryptophan, is expressed by a variety of cells and tissues such as macrophages, dendritic cells, cells of the endocrine system and by the placenta. IFN- γ is the main inducer of this enzyme. IDO acts as an important defense mechanism of innate immunity against pathogens. It also has tumor suppressive activity and prolong...
متن کاملIndoleamine 2,3-Dioxygenase and Immunological Tolerance during Pregnancy
Indoleamine 2,3-dioxygenase (IDO), an enzyme involved in the catabolism of tryptophan, is expressed by a variety of cells and tissues such as macrophages, dendritic cells, cells of the endocrine system and by the placenta. IFN-γ is the main inducer of this enzyme. IDO acts as an important defense mechanism of innate immunity against pathogens. It also has tumor suppressive activity and prolongs...
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BACKGROUND Expression of the tryptophan catabolizing enzyme, indoleamine 2,3-dioxygenase, in the mouse placenta has been shown to be critical in preventing immunological rejection of the fetal allograft. To clarify the physiological importance of indoleamine 2,3-dioxygenase in human pregnancy, we have studied how the expression of this enzyme changes during decidualization of human endometrium ...
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