Microglia nodules in MS had an increased expression of genes implying T- and B-cell homeostasis and proliferation (compared to MS non-nodular NAWM: NCKAP1L, CASP3, JAK3, FADD, TCIRG1, after correction NCKAP1L; compared to microglia nodules in stroke: CORO1A, NCKAP1L, CASP3, APBB1IP, none after correction) and natural killer T (NKT) cell-mediated cytotoxicity (compared to microglia nodules in stroke: GRB2, CASP3, BID, none after correction). The gene discussed is GRB2; the disease is myeloid sarcoma.