Article

Immunoregulatory effects of indoleamine 2, 3-dioxygenase in transplantation.

Department of Renal Transplantation, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China.
Transplant Immunology (impact factor: 1.46). 06/2009; 21(1):18-22. pp.18-22
Source: PubMed

ABSTRACT Indoleamine 2, 3-dioxygenase (IDO) is an intracellular hemeprotein enzyme which catalyses the essential amino acid tryptophan. Accumulating evidence has demonstrated that tryptophan depletion and its toxic metabolites expression in tissue microenvironment can suppress local allogeneic T cell proliferation and activation. Ever since the discovery that IDO was involved in the maintenance of fetal-maternal tolerance, numerous studies have confirmed that IDO is a potent regulator of immune cell function. Importantly, IDO+dendritic cells (DCs) might interact with regulatory T cells (Tregs) to form an immunomodulatory network to promote immune tolerance induction. Moreover, it has been reported that overexpression of IDO in transplanted organs can prolong allograft survival, suggesting a possible peripheral tolerogenic pathway with important implications in transplantation. However, the underlying mechanism for the beneficial effects of IDO in transplantation remains unclear. In this review, we attempt to summarize our current understandings about IDO as a mediator of immunity in transplantation and provide an overview of IDO as a new paradigm in transplantation.

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    Article: Human cytomegalovirus IE1 protein elicits a type II interferon-like host cell response that depends on activated STAT1 but not interferon-γ.
    Theresa Knoblach, Benedikt Grandel, Jana Seiler, Michael Nevels, Christina Paulus
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    PLoS Pathogens 04/2011; 7(4):e1002016. · 9.13 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

Accumulating evidence
 
allograft survival
 
current understandings
 
essential amino acid tryptophan
 
fetal-maternal tolerance
 
IDO
 
IDO+dendritic cells
 
immune cell function
 
immune tolerance induction
 
Indoleamine 2
 
intracellular hemeprotein enzyme
 
local allogeneic T cell proliferation
 
new paradigm
 
overview
 
possible peripheral tolerogenic pathway
 
potent regulator
 
regulatory T cells
 
toxic metabolites expression
 
transplantation
 
underlying mechanism
 

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