There was an increase in the percentage of TLR9+ cells, particularly CD34+TLR9+ cells, in MDS compared to normal BM (Figure 2E, Supplemental Figure S5), and particularly in the stem (CD34+CD71−CD14−, CD34+CD33−) and progenitor (CD34+CD38−) populations (Figure 2F). Here, TLR9 is linked to myelodysplastic syndrome.