PSMB9 and post-transplant lymphoproliferative disease: PTLD display Latency III infection, and all the eight EBV latent antigens are expressed, including six EBV nuclear antigens EBNA 1, EBNA2, EBNA3A, EBNA3B, EBNA 3C, EBNA 6/LP and two latent membrane proteins LMP1 and LMP2 (41, 42).