Dataset Information

Dynamics of HIV-1 recombination in its natural target cells.

ABSTRACT: Genetic recombination is believed to assist HIV-1 diversification and escape from host immunity and antiviral therapies, yet this process remains largely unexamined within the natural target-cell populations. We developed a method for measuring HIV-1 recombination directly that employs reporter viruses bearing functional enhanced yellow fluorescent protein (YFP) and enhanced cyan fluorescent protein (CFP) genes in which recombination produces a modified GFP gene and GFP fluorescence in the infected cells. These reporter viruses allow simultaneous quantification of the dynamics of HIV-1 infection, coinfection, and recombination in cell culture and in animal models by flow-cytometric analysis. Multiround infection assays revealed that productive cellular coinfection was subject to little functional inhibition. As a result, generation of recombinants proceeded according to the square of the infection rate during HIV-1 replication in T lymphocytes and within human thymic grafts in severe combined immunodeficient (SCID)-hu (Thy/Liv) mice. These results suggest that increases in viral load may confer a compounding risk of virus escape by means of recombinational diversification. A single round of replication in T lymphocytes in culture generated an average of nine recombination events per virus, and infection of macrophages led to approximately 30 crossover events, making HIV-1 up to an order of magnitude more recombinogenic than recognized previously and demonstrating that the infected cell exerts a profound influence on the frequency of recombination.

SUBMITTER: Levy DN

PROVIDER: S-EPMC384719 | biostudies-literature | 2004 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Dynamics of HIV-1 recombination in its natural target cells.

Levy David N DN Aldrovandi Grace M GM Kutsch Olaf O Shaw George M GM

Proceedings of the National Academy of Sciences of the United States of America 20040309 12

Genetic recombination is believed to assist HIV-1 diversification and escape from host immunity and antiviral therapies, yet this process remains largely unexamined within the natural target-cell populations. We developed a method for measuring HIV-1 recombination directly that employs reporter viruses bearing functional enhanced yellow fluorescent protein (YFP) and enhanced cyan fluorescent protein (CFP) genes in which recombination produces a modified GFP gene and GFP fluorescence in the infec ...[more]

PMID: 15010526

Similar Datasets

Project description:A series of HIV-1 CRF01_AE/CRF07_BC recombinants were previously found to have emerged gradually in a superinfected patient (patient LNA819). However, the extent to which T-cell responses influenced the development of these recombinants after superinfection is unclear. In this study, we undertook a recombination structure analysis of the gag, pol, and nef genes from longitudinal samples of patient LNA819. A total of 9 pol and 5 nef CRF01_AE/CRF07_BC recombinants were detected. The quasispecies makeup and the composition of the pol and nef gene recombinants changed continuously, suggestive of continuous evolution in vivo. T-cell responses targeting peptides of the primary strain and the recombination regions were screened. The results showed that Pol-LY10, Pol-RY9, and Nef-GL9 were the immunodominant epitopes. Pol-LY10 overlapped with the recombination breakpoints in multiple recombinants. For the LY10 epitope, escape from T-cell responses was mediated by both recombination with a CRF07_BC insertion carrying the T467E/T472V variants and T467N/T472V mutations originating in the CRF01_AE strain. In pol recombinants R8 and R9, the recombination breakpoints were located ~23 amino acids upstream of the RY9 epitope. The appearance of new recombination breakpoints harboring a CRF07_BC insertion carrying a R984K variant was associated with escape from RY9-specific T-cell responses. Although the Nef-GL9 epitope was located either within or 10~11 amino acids downstream of the recombination breakpoints, no variant of this epitope was observed in the nef recombinants. Instead, a F85V mutation originating in the CRF01_AE strain was the main immune escape mechanism. Understanding the cellular immune pressure on recombination is critical for monitoring the new circulating recombinant forms of HIV and designing epitope-based vaccines. Vaccines targeting antigens that are less likely to escape immune pressure by recombination and/or mutation are likely to be of benefit to patients with HIV-1.

Dataset Information

Dynamics of HIV-1 recombination in its natural target cells.

Publications

Dynamics of HIV-1 recombination in its natural target cells.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets