Molecular markers of clonality and identity in epstein–barr virus‐associated B‐cell lymphoproliferative disease

Abstract

Epstein-Barr virus (EBV)-associated B-cell lymphoproliferative disease may be polyclonal, oligoclonal, or monoclonal. The degree of tumor clonality reflects the disease pathogenesis and may have implications for disease diagnosis, prognosis, and treatment. In this study, specimens of EBV-associated B-cell lymphoproliferative disease obtained from immunocompromised hosts were analyzed for molecular markers of cellular and virologic clonality and virologic identity. Each tumor specimen was assessed for immunoglobulin gene JH region rearrangement, the structure of the EBV genome termini, and the EBV genotype(s) present using a new EBV genotyping assay based upon LMP-1 gene sequence variation. The results of the JH rearrangement and EBV termini assays were generally concordant in their assessment of tumor specimen clonality, and both assays contributed to establishing clonal identity between different tumor specimens. The EBV genotyping assay did not significantly contribute to the assessment of tumor clonality but did established clear virologic identity between different tumor specimens obtained from the same individual. In one individual, these three assays together characterized a multi-focal, monoclonal tumor that may have arisen through clonal selection after sequential infections with two different EBV genotypes. In summary, the JH rearrangement and EBV termini assays each provided different but complementary information on tumor clonality, while the EBV genotyping assay proved most useful for establishing virologic identity among tumors. Utilization of these three assays together may provide new insight into the pathogenesis of EBV-associated B-cell lymphoproliferative disease.

Nasopharyngeal Carcinoma: An Evolving Role for the Epstein–Barr Virus

“…However, the clonality of the viral episome enabled the identification of clonality in carcinomas. Analyses of Ig rearrangement and EBV termini confirmed the relationship between viral and cellular clonality (Katz et al 1989;Walling et al 2004). Multiple subsequent studies have identified clonal EBV in most of malignancies associated with EBV including Hodgkin's lymphoma, salivary gland carcinoma, and gastric cancer, and clonal termini have become one of the criteria indicating a etiologic role for EBV in these cancers (Raab-Traub et al 1991;Weiss et al 1988).…”

“…Thus, in the absence of recognition by cytotoxic lymphocytes, EBV-infected lymphocytes are able to switch to the transforming growth mode of expression resulting in lymphoma. In some cases, multiple clonal tumors are identified in different organs (Walling et al 2004). This detailed understanding of the EBV immune response has led to the first clearly effective viralspecific immunotherapy or prophylaxis where EBV-specific CTLs are expanded ex vivo by exposure to EBV transformed lymphocytes (Heslop et al 1999).…”

Pediatric post-transplant lymphoproliferative disorder after cardiac transplantation

“…Clonality can be assessed using immunoglobulin heavy chain gene rearrangement and EBV termini assays [66]. Flow cytometric analysis can also be used to determine monoclonality of B-cell lesions and T-cell lesions when immunoglobulin light chain (j or k) restriction or loss of surface or cytoplasmic immunoglobulin and abnormal T-cell antigen expression or loss is identified, respectively [67].…”

Effect of Epstein-Barr Virus Sequence Variation on Performance of the Roche Real-Time LightCycler PCR Assay

“…(3). EBV sequence variation is a recognized phenomenon (2-4) and has been used for EBV genotyping (4). Sequencing of the carboxyl-terminal region of the LMP1 gene showed that multiple variants (one to seven clones) may coexist in an individual (3).…”