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 (ĭn′dō-lăm′ēn, ĭn′dō-lə-mēn′)
Any of various naturally occurring analogs of indole, such as serotonin, containing an amine group.
References in periodicals archive ?
The company stated that IO102 is its lead candidate and is an Indoleamine 2,3-dioxygenase (IDO) derived immune modulating therapy with a dual mode of action - killing both cancer cells and immune-suppressive cells.
Tryptophan is also metabolized by a separate pathway to kynurenine by the enzyme, indoleamine 2,3-dioxygenase (IDO).
Hypotensive activity of the pineal indoleamine hormones melatonin, 5-methoxytryptophol and 5-methoxytryptamine.
[102] Other tumour evasion/escape strategies include the recruitment of immunosuppressive T-regulatory cells (T-regs) and monocytederived myeloid suppressor cells (MDSCs), and inhibitory indoleamine 2,3-dioxygenase (IDO), tryptophan 2,3-dioxygenase (TDO) and arginase-1 enzymes, which render immune cells deficient of tryptophan and arginine required for optimal functioning.
Furthermore, increased cyclooxygenase-2 (CQX-2) expression as well as prostaglandin E2 production in schizophrenia, are among other postulated etiologies supported by recent studies On the other hand, it has been shown that immune response imbalance is associated with decreased activity of indoleamine 2, 3-dioxygenase enzyme which subsequently leads to accumulation of kynurenic acid, an endogenous antagonist of glutamate N-methyl-D-aspartate (NMDA) receptor.
Liu et al., "Indoleamine 2,3-dioxygenase controls conversion of [Foxp3.sup.+] Tregs to TH17-like cells in tumor-draining lymph nodes," Blood, vol.
Namely, soluble immune secretomes, such as prostaglandin E2 (PGE-2), indoleamine 2,3-dioxygenase (IDO), or nitric oxide (NO), respond to immune cells to activate immunoregulation by MSCs [23].
The PD1/PDL1 reverse signaling can induce the expression of indoleamine 2,3-dioxygenase 1 (IDO1) in the tumor cells, which in turn causes phosphorylation of eIF2[alpha] with subsequent activation of ATF4 [17] and inhibition of IRF7 activity [18] in Treg, dendritic cells, myeloid derived suppressor cells, and endothelial cells [27].
This new molecule, a derivative of tryptophan, is an indoleamine (N-acetyl-5-methoxytryptamine) that was called melatonin, name derived from its effect in blanching the melanophores (mela-) in amphibians and because the precursor to melatonin is serotonin (-tonin).
Additionally, CTLA-4 induces the expression of the enzyme indoleamine 2,3-dioxygenase (IDO) by DCs, which catalyzes degradation of the essential amino acid tryptophan to kynurenine, leading to effector T cell starvation [25].
Lee, "Salmonella overcomes tumor immune tolerance by inhibition of tumor indoleamine 2, 3-dioxygenase 1 expression," Oncotarget, vol.
(1,17) Despite such a "hostile" microenvironment full of immune cells, MSI-H tumor cells are not eliminated by the immune system because of the cancer-specific upregulation of inhibitory checkpoints, including PD-1, CTLA4, LAG3, and indoleamine 2,3-dioxygenase (IDO).