ESTABLISHMENT AND CHARACTERIZATION OF EBV-POSITIVE AND EBV-NEGATIVE PRIMARY EFFUSION LYMPHOMA CELL-LINES HARBORING HUMAN-HERPESVIRUS TYPE-8

In this study we report on the establishment and characterization of t wo novel lymphoma cell lines (CRO-AP/3 and CRO-AP/5) which carry infec tion by human herpesvirus type-8 (HHV-8) and have derived from AIDS-re lated primary effusion lymphoma (PEL). These two cell lines are repres entative of different virologic subtypes of PEL, i.e. HHV-8(+)/EBV- PE L in the case of CRO-AP/3 and HHV-8(+)/EBV+ PEL in the case of CRO-AP/ 5. Consistent with the diagnosis of PEL, both CRO-AP/3 and CRO-AP/5 ex pressed indeterminate (i.e. non-B, non-T) phenotypes although immunoge notypic studies documented their B-cell origin, Both cell lines are de void of genetic lesions of c-MYC, BCL-2 and p53 as well as gross rearr angements of BCL-6. Detailed histogenetic characterization of these no vel PEL cell lines suggests that PEL may derive from a post-germinal c entre B cell which has undergone pre-terminal differentiation. The CRO -AP/3 and CRO-AP/5 cell lines may provide a valuable model for clarify ing the pathogenesis of PEL. In particular, these cell lines may help understand the relative contribution of HHV-8 and EBV to PEL growth an d development and may facilitate the identification of recurrent cytog enetic abnormalities highlighting putative novel cancer related loci r elevant to PEL.