Oncogenicity of gibbon type‐C myelogenous leukemia virus

Abstract

Young gibbons that were experimentally inoculated with cell-free gibbon ape leukemia virus (GaLV) and developed peristent viremia subsequently developed chronic granulocytic leukemia (CGL) with associated multifocal bone lesions and metastases. An 8-month-old gibbon inoculated with 10(5) tissue culture infectious virus (TCIV) developed acute myeloproliferative disease with associated bone lesions after a latency of 5 months, while a 9-month-old gibbon inoculated with 10(3) TCIV developed CGL after and 11-month latency. The clinical symptoms associated with the onset of leukemia were an increased number of leukocytes which were predominantly mature granulocytes, development of anemia, and multifocal bone lesions. Terminally, the animals had elevated immature granulocytes in the blood, cellular bone marrow with a predominant number of immature granulocytes, and hepatosplenomegaly. The gibbon with CGL had metastatic growth in the spleen and lung. Two 14-month-old gibbons that were inoculated with 10(3) TCIV and developed persistent neutralizing antibody to the virus infection remained free of hematopoietic disease, as did uninoculated animals. The fact that only animals with persistent viremia developed leukemia supports the oncogenicity of GaLV in gibbons.

Extended Analysis of the In Vitro Tropism of Porcine Endogenous Retrovirus

“…However, in vitro infection may not always correlate to in vivo infectivity. For example, gibbon ape leukemia virus can infect rat cell lines in vitro (16,19), but rats are not susceptible to infection in vivo (3). Alternatively, a species may be susceptible to infection in vivo, but a derivative cell line(s) may not be sensitive to infection by a given virus.…”

Endogenous Gibbon Ape Leukemia Virus Identified in a Rodent (Melomys burtoni subsp.) from Wallacea (Indonesia)

“…Gibbons in particular are surprising hosts: the fact that GALVs have been isolated only from captive and not wild gibbons suggests that they may be accidental hosts and that they have had infrequent but regular contact with a GALV reservoir or host species but only in captive facilities. This is particularly relevant for the gibbon colony housed at the SEATO Laboratory in Bangkok, Thailand (12), from which the other non-Asian gibbon colonies originated. GALV infects cells using a ubiquitous transmembrane protein that functions as sodium-dependent phosphate transporter called PiT1 or SLC20A1 (52).…”

“…KoRV is a potentially infectious endoge-nous retrovirus (ERV) of wild koalas (Phascolarctos cinereus) in Australia and captive koalas worldwide (9)(10)(11). Both viruses are associated with lymphoid neoplasms in their hosts (12,13). KoRV and GALV share high nucleotide sequence similarity (80%) and form a monophyletic clade within gammaretroviruses (2).…”

No Evidence for Infection of Human Embryonic Stem Cells by Feeder Cell–Derived Murine Leukemia Viruses

“…For coculture with hESCs, approximately 2.5 × 10 5 MLV-X cells were mixed with 2.5 × 10 5 MEFs and treated with mitomycin C as described above. A total of 7 × 10 5 hESCs was cultured for 5 days on these cells and was analyzed after an additional seven to eight passages on human feeder cells.…”

“…Some endogenous retroviruses are able to infect foreign species, and some cause diseases, including leukemias, neuropathological effects, and immunodeficiencies, in mice and immunosuppressed primates [5][6][7][8][9][10][11]. Murine endogenous retroviruses, especially mouse mammary tumor virus-related Btype retroviruses and C-type retroviruses of the murine leukemia virus (MuLV) group, are the most extensively investigated endogenous viruses.…”