Rhesus lymphocryptovirus type 1-associated B-cell nasal lymphoma in SIV-infected rhesus macaques

Area of Science:

• Virology
• Oncology
• Immunology

Background:

• Epstein-Barr virus (EBV), a gamma herpesvirus, infects over 90% of the global population and is associated with various malignancies, particularly lymphomas in immunosuppressed individuals.
• Extranodal lymphomas, including those in the sinonasal tract, are rare, accounting for less than 5% of all extranodal lymphomas. Sinonasal non-Hodgkin's lymphomas show increased incidence in human immunodeficiency virus (HIV)-infected patients.
• Rhesus lymphocryptovirus (rhLCV), the macaque homolog of EBV, is known to cause B-cell lymphomas in immunosuppressed macaques.

Observation:

• This report describes two cases of B-cell lymphoma in the nasal cavity of simian immunodeficiency virus (SIV)-infected rhesus macaques with acquired immunodeficiency syndrome (AIDS).

Findings:

• Immunohistochemistry and confocal microscopy confirmed the B-cell phenotype and rhLCV association in the neoplastic lymphocytes.
• Polymerase chain reaction (PCR) verified the presence of RhLCV type 1 sequences within the neoplasms.
• Immunohistochemical analysis revealed that the majority of neoplastic B lymphocyte nuclei were positive for EBNA-2, a key EBV-associated protein.

Implications:

• These findings highlight nasal lymphoma as an unusual presentation of rhLCV-associated B-cell lymphoma in immunosuppressed macaques.
• The study suggests comparable viral pathogenesis between rhLCV-induced nasal lymphomas in macaques and EBV-induced nasal lymphomas in HIV-positive humans.
• This research provides insights into the oncogenic mechanisms of lymphocryptoviruses in different primate species, potentially informing strategies for managing EBV-related malignancies.