CD4 and myeloid sarcoma: This notion is strengthened by our findings that GM-CSF- and IFNγ-producing Th17 cells bear a CCR6−CCR2+ phenotype in humans, other studies demonstrating that IFNγ-producing Th17 cells are preferentially recruited in MS lesions31, the observation that IL-17A/GM-CSF co-expressing CD4+ T cells are enriched in MS brain lesions32 and the well-established dependency on CCR2 for monocyte infiltration of the CNS46.