Such effects might explain some of the amelioration in relapse activity during 3rd trimester of pregnancy, however our study clearly ruled out that PDL1 and IL10 were increased due to changes in type 1 interferons, since the type 1 interferon-induced genes, MX1 and USP18, were not differentially expressed in pregnant and non-pregnant women with MS. The gene discussed is USP18; the disease is myeloid sarcoma.