Antibodies to human T-cell leukemia virus-membrane antigens in macaques with malignant lymphoma

Animal models for human T-lymphotropic virus type 1 (HTLV-1) infection and transformation

Over the past 25 years, animal models of human T-lymphotropic virus type 1 (HTLV-1) infection and transformation have provided critical knowledge about viral and host factors in adult T-cell leukemia/lymphoma (ATL). The virus consistently infects rabbits, some non-human primates, and to a lesser extent rats. In addition to providing fundamental concepts in viral transmission and immune responses against HTLV-1 infection, these models have provided new information about the role of viral proteins in carcinogenesis. Mice and rats, in particular immunodeficient strains, are useful models to assess immunologic parameters mediating tumor outgrowth and therapeutic invention strategies against lymphoma. Genetically altered mice including both transgenic and knockout mice offer important models to test the role of specific viral and host genes in the development of HTLV-1-associated lymphoma. Novel approaches in genetic manipulation of both HTLV-1 and animal models are available to address the complex questions that remain about viral-mediated mechanisms of cell transformation and disease. Current progress in the understanding of the molecular events of HTLV-1 infection and transformation suggests that answers to these questions are approachable using animal models of HTLV-1-associated lymphoma.

Epstein-Barr virus-related herpesvirus from a rhesus monkey (Macaca mulatta) with malignant lymphoma

A herpesvirus (RhEBV) was isolated from a lymphoblastoid cell line (LCL) that became established from a malignant lymphoma in a rhesus monkey. The predominant cell marker in the LCL was that of B lymphocytes. RhEBV-induced viral capsid (VCA) and nuclear antigens (NA) in the LCL were serologically related to similar antigens known to be induced by human Epstein-Barr virus (EBV). RhEBV was of nonhuman primate origin and was clearly differentiated from EBV in the anti-complement immunofluorescence reaction using human and non-human primate sera with antibodies to the NA induced by the respective viruses. While human sera reacted with NA induced by both EBV and RhEBV, monkey sera failed to recognize the NA induced by EBV. RhEBV-induced NA was present in nearly all the cells of a suspension prepared from the tumor tissue mass, but not in the monolayer fibroblasts derived from the tumor tissue or in the blood and lymph-node lymphocytes of clinically healthy animals. RhEBV induced in vitro transformation and establishment of LCLs from peripheral blood lymphocytes of normal rhesus and cynomolgus monkeys but not from those of 6 other non-human primate species tested. The LCLs, with predominant B-lymphocyte markers, established after treatment with RhEBV, all had evidence of the virus infection since nearly all cells in the culture expressed the virus-induced NA.