In addition, the significantly lower expression of HLA-DR molecules and co-stimulatory molecules, such as CD80/86 and CD40, may indicate that PBDCs (myeloid DCs (BDCA-1+ or CD11c+ CD33+) and pDCs (BDCA-2+ or CD123+)) in MM patients are in an immature state and as a consequence possess impaired Ag presentation capacities [20,21]. Here, CD80 is linked to Miyoshi myopathy.