Increased level of arginase activity correlates with disease severity in HIV-seropositive patients.
Infection with human immunodeficiency virus (HIV) results in a chronic infection that progressively impairs the immune system. Although depletion of CD4(+) T cells is frequently used to explain immunosuppression, chronicity of infection and progressive loss of CD4(+) T cells are not sufficient to fully account for immune dysregulation. Arginase-induced l-arginine deprivation is emerging as a key mechanism for the down-regulation of immune responses. Here, we hypothesized that the level of arginase activity increases with disease severity in HIV-seropositive patients. We determined the levels of arginase activity in peripheral blood mononuclear cells from HIV-seropositive patients and uninfected control participants. Our results show that peripheral blood mononuclear cells from HIV-seropositive patients with low CD4(+) T cell counts expressed statistically significantly higher levels of arginase activity, compared with patients with high CD4(+) T cell counts or uninfected control participants. Furthermore, we found a statistically significant correlation between high level of arginase activity and high viral load in HIV-seropositive patients.
Cloke
T E
TE
Department of Immunology, Faculty of Medicine, Imperial College London, London, United Kingdom.
Garvey
L
L
Choi
B-S
BS
Abebe
T
T
Hailu
A
A
Hancock
M
M
Kadolsky
U
U
Bangham
C R M
CR
Munder
M
M
Müller
I
I
Taylor
G P
GP
Kropf
P
P
D000328:Adult; D001119:Arginase / Q000378:metabolism*; D018791:CD4 Lymphocyte Count; D002478:Cells, Cultured; D005260:Female; D006678:HIV / Q000302:isolation & purification; D015658:HIV Infections / Q000276:immunology / Q000473:pathology*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000201:enzymology*; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D019562:Viral Load
D001119:Arginase