We collected peripheral blood CD4+ T cells from MS patients and healthy controls and found MS patients had a more significantly upregulated expression of TLR4 (> 5 folds) in CD45RO+ memory CD4+ T cells than CD45RA+ naïve T cells compared with that in healthy controls (< 2 folds) (Fig. 1a). Here, CD4 is linked to myeloid sarcoma.