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Indoleamine 2,3 Dioxygenase, Age, and Immune Activation in People Living with Hiv

Lookup NU author(s): Dr Lei HuangORCiD, Emeritus Professor Andrew MellorORCiD



This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).


© American Federation for Medical Research 2021. No commercial re-use. See rights and permissions. Published by BMJ.Immune activation complicates HIV despite antiretroviral therapy (ART). Indoleamine 2,3 dioxygenase (IDO) catabolizes tryptophan (T) to kynurenine (K), regulating immune activity, and IDO activity increases with age. This study examines the relationship of IDO activity, bacterial translocation, and aging in people living with HIV (PLWH) on ART. Samples and data from PLWH on ART from the Centers for AIDS Research Network of Integrated Clinical Systems and from matched HIV-uninfected patients (controls) from the Multicenter AIDS Cohort Study and the Women's Interagency HIV Study were analyzed. The ratio of K to T (K:T) and neopterin were indicators of inflammation; 16S ribosomal DNA (16S rDNA) and lipopolysaccharide (LPS) were markers of bacterial translocation. Samples and data from 205 PLWH and 99 controls were analyzed. PLWH had higher K:T values across all ages, with a significant relationship between age and K:T for both groups. CD4 count or CD4 nadir had no association with K:T. There was no positive association between level of 16S rDNA or LPS detection and K:T. K:T and neopterin were associated. PLWH had elevated IDO activity, at younger ages, despite ART. This study suggests K:T ratio increases with age in both groups and is elevated in PLWH at all ages compared with age-matched controls.

Publication metadata

Author(s): Baer SL, Colombo RE, Johnson MH, Wakade S, Pacholczyk G, Newman-Whitlow C, Thompson SA, Saag MS, Martin JN, Floris-Moore M, Huang L, Mellor AL

Publication type: Article

Publication status: Published

Journal: Journal of Investigative Medicine

Year: 2021

Volume: 69

Issue: 6

Pages: 1238-1244

Print publication date: 01/08/2021

Online publication date: 01/08/2021

Acceptance date: 23/03/2021

Date deposited: 02/07/2021

ISSN (print): 1081-5589

ISSN (electronic): 1708-8267

Publisher: BMJ Publishing Group


DOI: 10.1136/jim-2021-001794

PubMed id: 33875612


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