Be trans infected in vivo. Indeed, a recent reportTERT-2 6 Figure cells
Be trans infected in vivo. Indeed, a recent reportTERT-2 6 Figure cells trans infect VLPs to MOLT-4/CCR5 cells TERT-2 cells trans infect VLPs to MOLT-4/CCR5 cells. TERT-2 cell monolayers were incubated for 6 h at 37 with replication-incompetent HIV-NL4-3 particles pseudotyped to express VSV-G envelope (VLPs) at a MOI 100. Cells were washed, then co-cultured with MOLT-4/ CCR5 PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/27597769 (2 ?105) cells, and EGFP expression in MOLT-4/ CCR5 cells was analyzed at 48 h using flow cytometry. The percentage of infected MOLT-4/CCR5 cells was quantified. Some TERT-2 monolayers were either treated with trypsin, colchicine (500 M for 30 min), pre-cooled to 4 , trypsin and pre-cooled to 4 , or trypsin and colchicine as described in the Materials and Methods. Data shown are the mean ?standard deviation from three independent experiments. specific RNA product PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/26100631 U5-U3 RNA. HIV-1 specific mRNAs appeared at levels that could not be clearly distinguished from contamination (data not shown). After low-level integration, therefore, HIV-1 replication aborts. Many steps in the HIV life cycle may be restricted by intrinsic cellular factors targeting viral entry, viral uncoating, viral DNA synthesis, MK-886 site intracellular trafficking of viral nucleic acids, integration, viral gene expression or viral packaging [41]. TERT-2 cells clearly restrict HIV replication after integration when infected with HIV-1. We sought to determine whether the internalization pathway used by HIV-1 in TERT-2 cells contributed to the restriction. Therefore we inoculated TERT-2 cells with VSV-G pseudotyped HIV-NL4-3env-EGFP particles, which internalizes promiscuously into an endosomal pathway [42]. When integrated, HIV LTR from the pseudotyped particles regulates green fluorescence expression in TERT2 cells (Fig. 3A and 3B). When the conventional, gp120-Page 9 of(page number not for citation purposes)Retrovirology 2008, 5:http://www.retrovirology.com/content/5/1/suggests that Langerin-positive dendritic cells degrade internalized HIV-1, reducing transfer to CD4+ T cells in the mucosa [57], while others show that activated CD34positive Langerhans cells increase trans infection of permissive target cells [58]. Unlike the female genital epithelium [17], oral Langerhans cells (dendritic cells) are not known to sample antigens or capture HIV-1 at the mucosal surface. Oral mucosal keratinocytes, therefore, could contribute to HIV transmission in vivo, however, by activating and trans infecting Langerhans cells, which can dock and transfer virus to CD4+ cells, or by transferring infectious harbored HIV-1 particles to proximal permissive cells. For the first time, we show that oral keratinocytes become infected by HIV-1, initiating a defined, truncated viral life cycle. While infection is non-productive, an intracellular pool of infectious HIV-1 is harbored for up to 48 h and fully capable of trans infecting CD4+ permissive cells. Hence, the oral epithelium may actively disseminate HIV1 infection and is more than an inert barrier. Since R5tropic HIV-1 is most frequently associated with primary infections, oral epithelium could function as a selective “gatekeeper” and exclude X4-tropic virus. When compared, oral keratinocytes from different sources selectively harbor and transfer HIV-1 in either an X4- or R5-tropic HIV-1-specific manner (data not shown). TERT-2 cells consistently harbor all HIV-1 strains tested, while primary tonsil epithelial cells from some donors did not support trans infection (Fig. 1A). Since.