Insertion of SMRV‐H viral DNA at the c‐myc gene locus of a BL cell line and presence in established cell lines

Abstract

Mutation of the c-myc gene locus has occurred during in vitro culture of the Burkitt lymphoma cell line Namalwa. Gene cloning and sequencing of this c-myc gene locus has revealed the insertion of incomplete copies of the Squirrel Monkey Retrovirus-Human (SMRV-H) proviral genome. Insertions of the SMRV-H genome were seen in all Namalwa cell lines tested, with multiple insertions being seen in some sublines. Viral particles with the morphology of type-D retrovirus, budding from these cells, were seen by transmission EM. New insertions of the genome were produced spontaneously in these cells. The origins of the type-D retrovirus and its implications for workers in the field are discussed.

Production of Genetically Modified Epstein-Barr Virus-Specific Cytotoxic T Cells for Adoptive Transfer to Patients at High Risk of EBV-Associated Lymphoproliferative Disease

“…B95-8 master cell bank B95-8 virus producer cells were tested for the presence of mycoplasma using a commercially available detection kit (Gen-Probe, San Diego, CA) for the presence of squirrel monkey retrovirus by Southern and western blotting (11) and for the presence of viruses other than EBV by electron microscopy. The cell line proved negative in all these tests and was cryopreserved to generate a master stock.…”

High-throughput detection and multiplex identification of cell contaminations

“…This type D retrovirus is classified in biological risk group 2 (9,10). Infection of other species is not described, but since contaminations of numerous vertebrate cell lines have been reported (11,12), the potential for in vivo infection cannot be excluded. Therefore, the German Central Commission for Biological Safety (ZKBS) recommended the testing of all used cell lines for SMRV.…”

Identification of Gammaretroviruses Constitutively Released from Cell Lines Used for Human Immunodeficiency Virus Research

“…3B), and the infectivity of the LacZ pseudotypes was specifically inhibited in cells Contamination of animal cell lines with retroviruses has been described several times in the literature (3,7,13,14,18,24,27,34,41,46), and the most frequent contaminants are reported to be gammaretroviruses (7,13,14,18,27,34,35,46). A likely cause of contamination with MLV is their passage through animals as xenoimplants (18,23).…”