In comparison with the role of ILCs, whether mounting a response to intra or extracellular pathogens, anti-helminthic, lymphoid tissue organogenesis, tissue repair or metabolic homeostasis, the role of ILC4s is not yet quite clear, as they were generated after IL-2 activation of NK cells from peripheral blood of healthy people or MS patients, besides their existence in CSF of MS patients without any prior activation (reviewed in [111]). This evidence concerns the gene IL2 and myeloid sarcoma.