Differential impact of L-arginine deprivation on the activation and effector functions of T cells and macrophages.
The metabolism of the amino acid L-arginine is emerging as a crucial mechanism for the regulation of immune responses. Here, we characterized the impact of L-arginine deprivation on T cell and macrophage (MPhi) effector functions: We show that whereas L-arginine is required unconditionally for T cell activation, MPhi can up-regulate activation markers and produce cytokines and chemokines in the absence of L-arginine. Furthermore, we show that L-arginine deprivation does not affect the capacity of activated MPhi to up-regulate L-arginine-metabolizing enzymes such as inducible NO synthase and arginase 1. Thus, our results show that to exert their effector functions, T cells and MPhi have different requirements for L-arginine.
Choi
B-S
BS
Department of Immunology, Faculty of Medicine, Imperial College London, UK.
Martinez-Falero
I Clara
IC
Corset
C
C
Munder
M
M
Modolell
M
M
Müller
I
I
Kropf
P
P
D000818:Animals; D001119:Arginase / Q000378:metabolism; D001120:Arginine / Q000172:deficiency* / Q000494:pharmacology; D015415:Biomarkers / Q000378:metabolism; D049109:Cell Proliferation; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D008213:Lymphocyte Activation / Q000276:immunology*; D008262:Macrophage Activation / Q000276:immunology*; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009569:Nitric Oxide / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000201:enzymology / Q000276:immunology*
D015415:Biomarkers; D016207:Cytokines; D009569:Nitric Oxide; D001120:Arginine; D001119:Arginase