Wk. Chang et al., Effect of glutamine on Th1 and Th2 cytokine responses of human peripheral blood mononuclear cells, CLIN IMMUNO, 93(3), 1999, pp. 294-301
Decreased glutamine concentrations are found in patients with catabolic str
ess and are related to susceptibility to infections. In this study, we eval
uated the role of glutamine in Th1/Th2 cytokine responses. Peripheral blood
mononuclear cells were stimulated with phytohemagglutinin (PHA), live atte
nuated bacillus Calmette-Guerin (BCG), or measles virus in the presence of
different glutamine concentrations. We found that glutamine at an optimal c
oncentration (0.6 mM) significantly enhanced PHA-stimulated lymphocyte prol
iferation as well as Th1 [interferon-gamma (IFN-gamma) and interleukin-2 (I
L-2)] and Th2 cytokine (IL-4 and IL-10) production. In the absence of gluta
mine, BCG and measles virus elicited minimal lymphocyte proliferation, wher
eas BCG enhanced Th1 cytokine response and measles virus promoted Th2 cytok
ine response. Interestingly, addition of glutamine promoted the BCG-elicite
d Th1 cytokine response (IFN-gamma), but suppressed the measles-induced Th2
cytokine response (IL-10). These results suggest that appropriate glutamin
e levels may influence host responses to different antigens and microorgani
sms. Furthermore, predominately Th1, but not Th2, cytokine responses requir
ed the presence of optimal concentrations of glutamine. (C) 1999 Academic P
ress.