Interestingly, we observed coexpression of CD80 and CD206 in a small fraction of Mf, in line with previous findings in circulating Mn from the systemic form of JIA (82), suggesting the presence of a subset of Mf with a mixed M1/M2 phenotype, probably representing M2-to-M1 switching cells. This evidence concerns the gene CD80 and juvenile idiopathic arthritis.