CD36-specific antibodies block release of HIV-1 from infected primary macrophages and its transmission to T cells.
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ABSTRACT:
SUBMITTER: Berre S
PROVIDER: S-EPMC3832921 | biostudies-literature |
REPOSITORIES: biostudies-literature
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2002-02-11 | E-GEOD-23 | biostudies-arrayexpress
Project description:Macrophages (Mø) and dendritic cells (DCs) are key players in human immunodeficiency virus (HIV) infection and pathogenesis. They are essential for the spread of HIV to CD4+ T lymphocytes (TCD4+) during acute infection. In addition, they constitute a persistently infected reservoir in which viral production is maintained for long periods of time during chronic infection. Defining how HIV interacts with these cells remains a critical area of research to elucidate the pathogenic mechanisms of acute spread and sustained chronic infection and transmission. To address this issue, we analyzed a panel of phenotypically distinct HIV-1 and HIV-2 primary isolates for the efficiency with which they are transferred from infected DCs or Mø to TCD4+. Our results show that infected Mø and DCs spread the virus to TCD4+ via cell-free viral particles in addition to other alternative pathways. We demonstrate that the production of infectious viral particles is induced by the co-culture of different cell populations, indicating that the contribution of cell signaling driven by cell-to-cell contact is a trigger for viral replication. The results obtained do not correlate with the phenotypic characteristics of the HIV isolates, namely their co-receptor usage, nor do we find significant differences between HIV-1 and HIV-2 in terms of cis- or trans-infection. The data presented here may help to further elucidate the cell-to-cell spread of HIV and its importance in HIV pathogenesis. Ultimately, this knowledge is critical for new therapeutic and vaccine approaches.
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Project description:Yeast cells were blocked in telophase using a cdc15-2 temperature senstive mutant at restrictive temperature. The culture was then shifted to permissive temperature (25oC), and released into the cell cycle. Samples were then taken during the course of almost three full cell cycles. This study is described in more detail in Spellman PT et al.(1998) Mol Biol Cell 9:3273-97 Keywords: time-course
2002-02-12 | GSE23 | GEO
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