Indoleamine 2,3-dioxygenase. A new, rapid, sensitive radiometric assay and its application to the study of the enzyme in rat tissues.
نویسندگان
چکیده
A simple and convenient assay for indoleamine 2,3-dioxygenase has been developed. This depends on the conversion of D-[ring-2-14C]tryptophan to [14C]formate, excess substrate is removed by adsorption onto charcoal. This assay, which is 20-fold more sensitive than previous procedures, is applicable both to crude extracts and to large numbers of samples. Activity in rat tissues is very much lower than in those of the rabbit; measureable activity is found only in the stomach, spleen, intestine and kidney. Enzyme activity in the rat intestine was increased by 50% in rats pretreated with L-tryptophan.
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...
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BACKGROUND Indoleamine 2,3-dioxygenase (IDO) is an enzyme associated with the regulation of immune responses. Cytokines such as IFNγ induce its expression in endothelial cells originating from immune-privileged sites. In this study, we investigate regulators of IDO in primary endothelial cells from a non-immune-privileged site and determine whether IDO expression affects immune cell behavior. ...
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ورودعنوان ژورنال:
- The Biochemical journal
دوره 189 3 شماره
صفحات -
تاریخ انتشار 1980