Open AccessDeterminants of Human Immunodeficiency Virus Type 1 Resistance to Membrane-Anchored gp41-Derived Peptides
Author(s) -
Sabine Lohrengel,
Felix Hermann,
Isabel Hagmann,
Heike Oberwinkler,
Laura Scrivano,
Caroline Hoffmann,
Dorotheé von Laer,
Matthias T. Dittmar
Publication year - 2005
Publication title -
journal of virology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.617
H-Index - 292
eISSN - 1070-6321
pISSN - 0022-538X
DOI - 10.1128/jvi.79.16.10237-10246.2005
Subject(s) - gp41 , biology , heptad repeat , point mutation , mutation , virology , peptide sequence , mutagenesis , peptide , virus , amino acid , viral replication , microbiology and biotechnology , v3 loop , genetics , gene , antibody , biochemistry , epitope
The expression of a membrane-anchored gp41-derived peptide (M87) has been shown to confer protection from infection through human immunodeficiency virus type 1 (HIV-1) (Hildinger et al., J. Virol. 75:3038-3042, 2001). In an effort to characterize the mechanism of action of this membrane-anchored peptide in comparison to the soluble peptide T-20, we selected resistant variants of HIV-1(NL4-3) and HIV-1(BaL) by serial virus passage using PM1 cells stably expressing peptide M87. Sequence analysis of the resistant isolates showed different patterns of selected point mutations in heptad repeat regions 1 and 2 (HR1 and HR2, respectively) for the two viruses analyzed. For HIV-1(NL4-3) a single amino acid change at position 33 in HR1 (L33S) was selected, whereas for HIV-1(BaL) the majority of the sequences obtained showed two amino acid changes, one in HR1 and one in HR2 (I48V/N126K). In both selections the most important contiguous 3-amino-acid sequence, GIV, within HR1, associated with resistance to soluble T-20, was not changed. Site-directed mutagenesis studies confirmed the importance of the characterized point mutations to confer resistance to M87 as well as to soluble T-20 and T-649. Replication capacity and dual-color competition assays revealed that the double mutation I48V/N126K in HIV-1(BaL) results in a strong reduction of viral fitness, whereas the L33S mutation in HIV-1(NL4-3) did enhance viral fitness compared to the respective parental viruses. However, the selected point mutations did not confer resistance to the more recently described optimized membrane-anchored fusion inhibitor M87o (Egelhofer et al., J. Virol. 78:568-575, 2004), strengthening the importance of this novel antiviral concept for gene therapy approaches.