In summary, our results reveal an expansion of effector TLR2+ and, mainly, TLR4+ T cells able to produce pro-inflammatory cytokines related to Th17 and Tc-17 phenotypes in symptomatic CCM patients, in association with a decrease in the frequency of IL-10-secreting TLR4+ T cells. This evidence concerns the gene TLR4 and cerebral cavernous malformation.