CD83 and myalgic encephalomeyelitis/chronic fatigue syndrome: Lactobacilli are one of the most studied probiotics which modulate immune responses in vivo and in vitro .6,20–22 The exposure of mo-DCs to L. reuteri-CFS has previously been shown to induce IL-6, IL-23 and IL-10 secretion in vitro .19 In agreement, when we differentiated monocytes to conventional mo-DCs and then exposed them to L. reuteri-CFS for in short-term cultures, cells were clearly activated as the expression of genes encoding pro-inflammatory cytokines and maturation marker CD83 were upregulated.