Persistent symptoms in former UNTAC soldiers are not associated with shifted cytokine balance

Background The pathogenesis of post-combat syndromes, such as Gulf War synd rome, is poorly understood. Recently, it has been postulated that the sympt oms of veterans with such syndromes are due to a disturbed cytokine balance shifted towards a T-helper (Th) 2 profile. We investigated this hypothesis in 21 symptomatic former UNTAC soldiers and compared their results with th ose obtained in 21 healthy former UNTAC soldiers matched forage, sex and mi litary force. Design The numbers of intracellular interleukin 4 (IL-4) and interferon gam ma- (IFN-gamma) producing CD4(+) and CD8(+) T lymphocytes (CD3(+)) were det ermined after in vitro stimulation with phorbol myristate acetate and-calci um ionophore in the presence of brefeldin to block secretion of induced cyt okines. Circulating concentrations and lipopolysaccharide- (LPS) or phytoha emagglutinin- (PKA) stimulated whole-blood production of the proinflammator y cytokines IL-1 beta, IL-1ra, tumour necrosis factor alpha (TNF-alpha) and IL-10 and IFN-gamma were measured. Results The numbers of CD4(+) and CD8(+) T lymphocytes positive for IL-4 or IFN-gamma production were not significantly different in patients and cont rol subjects. After stimulation with LPS or PHA, the in vivo circulating co ncentration and concentration of IL-10 and IFN-gamma were also similar. Conclusions The present study demonstrates that there is no shift in cytoki ne balance towards a Th2 profile in former UNTAC soldiers with symptoms sim ilar to those of the Gulf War syndrome.