Transmissible retrovirus in Epstein-Barr virus-producer B95-8 cells.
Epstein-Barr virus (EBV) released from the B95-8 marmoset cell line has served as a prototype for biologic and biochemical studies of EBV. Here we identify and characterize a retrovirus carried by many cultures of B95-8 cells. The experiments were stimulated by the isolation of a cDNA clone from B95-8 cells in which sequences from the EBV large internal repeat were linked to gag sequences similar to those of squirrel monkey retrovirus, human isolate, SMRV-H. However, among 413 amino acids predicted from the nucleotide sequence of the gag region of the B95-8 SMRV isolate there were 48 amino acid changes that distinguished this virus from SMRV-H originally isolated from a human lymphoid cell line by Oda et al. (1988, Virology 167, 468-476). Nucleic acid and antibody probes were developed for the B95-8 isolate of SMRV. Using such probes, we found that SMRV-B95-8 was readily transmissible, independent of EBV, as an infectious virus to human B and T cell lines. SMRV-B95-8 was highly fusogenic in the presence or absence of EBV. The ultrastructural appearance of the B95-8 retrovirus was characteristic of a type D retrovirus. Cells dually infected with EBV and SMRV-B95-8 did not demonstrate increased levels of lytic EB viral replication. SMRV-B95-8 did not by itself cause lymphocyte immortalization or enhance immortalization by EBV. Thus SMRV-B95-8 does not contribute to the major biologic properties of the B95-8 strain of EBV.
Sun
R
R
Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
Grogan
E
E
Shedd
D
D
Bykovsky
A F
AF
Kushnaryov
V M
VM
Grossberg
S E
SE
Miller
G
G
D000595:Amino Acid Sequence; D000818:Animals; D001402:B-Lymphocytes; D001483:Base Sequence; D030121:Betaretrovirus / Q000302:isolation & purification* / Q000502:physiology / Q000648:ultrastructure; D002144:Callithrix; D002460:Cell Line; D003001:Cloning, Molecular; D017931:DNA Primers; D018076:DNA, Complementary; D015723:Gene Library; D015683:Gene Products, gag / Q000096:biosynthesis / Q000235:genetics; D015750:Genes, gag; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000502:physiology*; D006801:Humans; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012091:Repetitive Sequences, Nucleic Acid; D012453:Saimiri; D013601:T-Lymphocytes; D014779:Virus Replication
D017931:DNA Primers; D018076:DNA, Complementary; D015683:Gene Products, gag