In patients with inflammatory demyelinating disease such as multiple sclerosis (MS), relapsing–remitting MS (RRMS), and anti-myelin oligodendrocyte glycoprotein disorder, the major cell types in CSF with pleocytosis were CD4+ and CD8+ T cells, with other cell types such as γδ T cells, natural killer (NK) cells, monocytes (MOs), macrophages (MФs), myeloid dendritic cells (mDCs), plasmacytoid dendritic cells (pDCs), neutrophils (NEUs), and B cells also identified at relatively low proportions. This evidence concerns the gene CD4 and myeloid sarcoma.