POSTTRANSPLANTATION LYMPHOPROLIFERATIVE DISORDERS FREQUENTLY CONTAIN TYPE-A AND NOT TYPE-B EPSTEIN-BARR-VIRUS

Two families of Epstein-Barr virus (EBV), type A and type B, have been defined on the basis of sequence divergence in the EBNA-2 gene. Type A EBV immortalizes B cells more efficiently in vitro and infects immun ocompetent individuals more commonly than type B EBV. However, increas ed rates of infection by type B EBV are seen in immunocompromised host s and in many lymphoid neoplasms associated with immunocompromise. The posttransplantation lymphoproliferative disorders (PT-LPDs) are a het erogeneous group of B-cell neoplasms that arise in the setting of immu nosuppressive therapy, and are associated with EBV infection. Whether type A and/or type B EBV are associated with PT-LPDs is unknown. There fore, we investigated 27 PT-LPD lesions from 22 solid-organ transplant recipients by polymerase chain reaction (PCR) at the EBNA-2 and EBNA- 3c loci to detect sequence deletions that distinguish the two EBV fami lies. Another locus, EBER, was examined by single-strand conformation polymorphism analysis (SSCP), in conjunction with direct sequencing in selected cases. Type A EBV was found in 24 of 27 cases (89%) as seen by amplification of the EBNA-2 and EBNA-3c regions. Four different EBE R polymorphisms were detected, confirming the presence of different ty pe A EBV isolates among these cases. Three cases were negative for inf ection by EBV. Surprisingly, despite the immunocompromised state of th e hosts, none of the 27 PT-LPD lesions harbored type B EBV. Thus, alth ough type B EBV may commonly infect peripheral blood lymphocytes in im munocompromised individuals, they do not appear to induce readily PT-L PD formation. (C) 1995 by The American Society of Hematology.