CD33 and acute myeloid leukemia: The pDCs in pDC-AML express similar levels of CD4, CD38, CD45, CD123, CD303 (in most cases), and HLA-DR as normal pDCs, but they frequently exhibit aberrant expression of CD5, CD7, CD13, CD22, CD25, CD34, CD56, CD117, and TdT, and loss of the normal pDC markers CD2 and CD33 in a proportion of cases [94,95,96] (Figure 6).