Cotransfection of HIV-1 molecular clones with restricted cell tropism may yield progeny virus with altered phenotype.
Seven infectious molecular clones were obtained from a human immunodeficiency virus type 1 isolate with rapid/high replicative capacity. Biological characterization of progeny viruses obtained after transfection of clones into peripheral blood mononuclear cells showed that six clones yielded virus with restricted cell tropism, whereas one clone yielded virus able to replicate in cell lines. Although transfection of each of the clones 12, 13, and 82 individually gave rise to viruses with restricted tropism, viruses recovered from cotransfection of the mixtures of these clones exhibited altered phenotype, inasmuch as they were able to replicate in cell lines. To test whether recombination and/or complementation has taken place in the mixture of clones 12 + 13 + 82, the progeny virus was diluted to end point in 15 parallel series. Viruses with diverse biological phenotypes were recovered. With the help of distinctive restriction enzyme markers in regions comprising the vpu/env junction and variable regions 4 and 5 (V4/V5) of the env gene, recombinant genotypes could be identified with high frequency. No particular biological phenotype could be linked to a certain genotype in this study. The results show that different coexisting variants may interact and thereby influence the biological phenotype of a viral population.
Department of Virology, School of Medicine, Karolinska Institute, Stockholm, Sweden.
W
W
Tan
R
R
Fredriksson
A
A
Björndal
P
P
Balfe
E M
EM
Fenyö
D001483:Base Sequence; D002460:Cell Line; D002478:Cells, Cultured; D003001:Cloning, Molecular; D004279:DNA, Viral; D015497:HIV-1 / Q000235:genetics* / Q000502:physiology; D006801:Humans; D007201:Indicator Dilution Techniques; D008969:Molecular Sequence Data; D009000:Monocytes / Q000382:microbiology; D010641:Phenotype; D011995:Recombination, Genetic; D014162:Transfection; D014407:Tumor Cells, Cultured; D014779:Virus Replication / Q000235:genetics
D004279:DNA, Viral