 In contrast to PBL, the plasmablastic cells in primary effusion lymphomas, whether HHV8-positive or HHV8-negative, usually strongly express CD45 and in HHV8 cases express HHV8 proteins such as the LANA-1 protein.Primary effusion lymphoma, HH8-negative also differs from PBL in that its plasmablastic cells frequently express certain B-cell marker proteins such as CD20 and CD79a.Various factors distinguish plasmablastic plasma cell lymphoma from PBL.