Arginase activity - a marker of disease status in patients with visceral leishmaniasis in Ethiopia
Author(s)
Type
Journal Article
Abstract
The underlying mechanisms resulting in the profound immune suppression characteristic of human visceral leishmaniasis (VL) are not fully understood.
Here, we tested the hypothesis that arginase, an enzyme associated with immunosuppression, is higher in patients with VL and contributes to impaired T cell responses. We recruited patients with VL before and after treatment and healthy controls and measured the arginase metabolism in the blood of these individuals. Our results show that arginase activity is significantly higher in the blood of patients with active VL as compared to controls. These high levels of arginase decline considerably once the patients are successfully treated. We identified the phenotype of arginase-expressing cells among PBMCs as neutrophils and show that their frequency was increased in PBMCs of patients before treatment; this coincides with reduced levels of L-arginine in the plasma and decreased expression levels of CD3ζ in T cells.
Here, we tested the hypothesis that arginase, an enzyme associated with immunosuppression, is higher in patients with VL and contributes to impaired T cell responses. We recruited patients with VL before and after treatment and healthy controls and measured the arginase metabolism in the blood of these individuals. Our results show that arginase activity is significantly higher in the blood of patients with active VL as compared to controls. These high levels of arginase decline considerably once the patients are successfully treated. We identified the phenotype of arginase-expressing cells among PBMCs as neutrophils and show that their frequency was increased in PBMCs of patients before treatment; this coincides with reduced levels of L-arginine in the plasma and decreased expression levels of CD3ζ in T cells.
Date Issued
2013-03-28
Date Acceptance
2013-02-09
Citation
PLOS Neglected Tropical Diseases, 2013, 7 (3)
ISSN
1935-2735
Publisher
Public Library of Science
Journal / Book Title
PLOS Neglected Tropical Diseases
Volume
7
Issue
3
Copyright Statement
© 2013 Abebe et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
License URL
Subjects
Science & Technology
Life Sciences & Biomedicine
Infectious Diseases
Parasitology
Tropical Medicine
PARASITOLOGY
TROPICAL MEDICINE
PLASMA AMINO-ACIDS
CYTOKINE PROFILES
SUPPRESSOR-CELLS
CUTANEOUS LEISHMANIASIS
ACTIVATED GRANULOCYTES
L-ARGININE
MECHANISMS
EXPRESSION
INFECTION
CANCER
Adolescent
Adult
Antigens, CD3
Arginase
Arginine
Biomarkers
Ethiopia
Humans
Immune Tolerance
Leishmaniasis, Visceral
Male
Neutrophils
T-Lymphocytes
Young Adult
Biological Markers
06 Biological Sciences
11 Medical And Health Sciences
Publication Status
Published
Article Number
e2134