The Maturation of Dendritic Cells Results in Postintegration Inhibition of HIV-1 Replication

Abstract

Maturation of dendritic cells (DC) is known to result in decreased capacity to produce HIV due to postentry block of its replicative cycle. In this study, we compared the early phases of this cycle in immature DC (iDC) and mature DC (mDC) generated from monocytes cultured with GM-CSF and IL-4, trimeric CD40 ligand (DCCD40LT), or monocyte-conditioned medium (DCMCM) being added or not from day 5. Culture day 8 cells exposed to X4 HIV-1LAI or R5 HIV-1Ba-L were analyzed by semiquantitative R-U5 PCR, which detects total HIV DNA. CXC chemokine receptor 4low (CXCR4low) CCR5+ iDC harbored similar viral DNA amounts when exposed to either strain. HIV-1LAI entered more efficiently into DCCD40LT or DCMCM with up-regulated CXCR4. CCR5low DCCD40LT still allowed entry of HIV-1Ba-L, whereas CCR5− DCMCM displayed reduced permissivity to this virus. Comparing amounts of late (long terminal repeat (LTR)-gag PCR) and total (R-U5 PCR) viral DNA products showed that HIV-1Ba-L reverse transcription was more efficient than that of HIV-1LAI, but was not affected by DC maturation. Southern blot detection of linear, circular, and integrated HIV DNA showed that maturation affected neither HIV-1 nuclear import nor integration. When assessing virus transcription by exposing iDC to pNL4-3.GFP or pNL4-3.Luc viruses pseudotyped with the G protein of vesicular stomatitis virus (VSV-G), followed by culture with or without CD40LT or MCM, GFP and luciferase activities decreased by 60–75% in mDC vs iDC. Thus, reduced HIV replication in mDC is primarily due to a postintegration block occurring mainly at the transcriptional level. We could not relate this block to altered expression and nuclear localization of NF-κB proteins and SP1 and SP3 transcription factors.

Lentiviral-mediated gene delivery in human monocyte-derived dendritic cells: Optimized design and procedures for highly efficient transduction compatible with clinical constraints

“…39 Poly( I:C ) triggered effective maturation of both control and transduced DCs as demonstrated by the up -regulation of CD83 expression and the secretion of large quantities of bioactive IL -12 p70, indicating that the lentiviral vectormodified monocyte -derived DCs were fully functional. Finally, it is remarkable that the level of transgene expression was conserved in these therapeutically relevant mature DCs, with a slight but reproducible increase in the mean fluorescence intensity, suggesting that in contrast to previous observations, 45 there was neither postintegration promoter silencing nor loss of transduced cells during maturation. Both the IL -12 secretion and the high -level transgene expression associated with mature transduced DCs are critical in generating strong CTL responses.…”

Dendritic cells cross-present HIV antigens from live as well as apoptotic infected CD4 + T lymphocytes

“…HLA-A2), Gag 20 -28 (RLRPGGKKK, HLA-A3), and human T-lymphotrophic virus-1 Tax [11][12][13][14][15][16][17][18][19] (LLFGYPVYV, HLA-A2) were from Neosystem (Strasbourg, France). The following mAbs were used: anti-MHC class I W6͞32 ascitis (1:100), anti-CD11c (pure or phycoerythrin-labeled) and anti-CD3-FITC (Becton Dickinson), and GaMIg-Cy5 (Caltag, South San Francisco, CA).…”

IFN-α Induces APOBEC3G, F, and A in Immature Dendritic Cells and Limits HIV-1 Spread to CD4+ T Cells

“…The coculture with activated apoptotic T cells also led to induction of MDDC maturation as measured by upregulation of costimulatory molecule CD80 and CD86 expression (19,20). Induction of MDDC maturation was previously shown to be accompanied by induction of A3G and A3F expression in MDDCs (7), and maturation suppresses HIV-1 infection through multifaceted mechanisms that involve decreased viral fusion (4), a block of reverse transcription (21), and a postintegration restriction that have been proposed to exist at the transcriptional level (22). In this study, we set out to investigate whether inducers of MDDC maturation such as TNF-a and IFN-a result in similar induction of expression of A3G, A3F, and A3A with subsequent inhibition of HIV-1 replication.…”