IL10 and myalgic encephalomeyelitis/chronic fatigue syndrome: In 2007, ter Wolbeek et al found higher levels of anti-inflammatory cytokines (IL-10 and IFN-γ/IL-10 ratios) and lower levels of proinflammatory cytokines (IL-6 and TNF-α) in adolescents with CFS compared to healthy controls.32 Reduced phytohemagglutinin-stimulated IFN-γ production by CD4+ T cells has been shown in CFS.33 This may support the idea that anti-inflammatory or regulatory pathways play some role in mediating persistent fatigue, after initial inflammatory insults.