IDO1 Human

IDO1 was first identified in rabbit small intestines in 1967 . The enzyme’s significance in immunosuppression, particularly in maternal-fetal tolerance, was described in 1998 . The crystal structure of human IDO1 was first reported in 2006 , providing insights into its functional mechanisms and potential as a therapeutic target.

IDO1 acts on multiple tryptophan substrates, including D-tryptophan, L-tryptophan, 5-hydroxy-tryptophan, tryptamine, and serotonin . The enzyme’s activity is typically low under normal physiological conditions but is significantly upregulated by proinflammatory cytokines such as interferon-γ . This upregulation is part of the innate immune response, helping to inhibit the growth of pathogens and parasites .

IDO1 plays a vital role in immunoregulation by exerting an immunosuppressive effect. This function is particularly important in maintaining maternal-fetal tolerance during pregnancy . Additionally, IDO1 expression by tumor cells contributes to tumor immune tolerance, aiding tumors in evading detection and destruction by the immune system . Chronic induction of IDO1 expression has been observed in cancer patients, with increased IDO1 activity correlating with a negative prognosis . Consequently, IDO1 has become an attractive pharmacological target for developing novel antineoplastic agents and adjuvants to enhance the efficacy of conventional chemotherapy .

Recombinant human IDO1 is produced using recombinant DNA technology, which involves inserting the human IDO1 gene into a suitable expression system, such as bacteria or yeast. This allows for the large-scale production of the enzyme for research and therapeutic purposes. Recombinant IDO1 is used in various assays to study its activity, regulation, and potential inhibitors .