Vels of viral particles, we speculate that average levels of host-viral chimeric transcripts in these cells exceed those in the two J-Lat cell lines. These results thus suggest that TI plays a key role in primary CD4+ T cells. In J-Lat 9.2 and 15.4 cells, the host-viral chimeric transcripts terminated at the pA site in the 5'LTR, but transcripts initiating at the host promoter and terminating at t
Lation than the 5'LTR, suggesting that the latter LTR is much stronger subjected to TI. Even if there is transcription from host gene `reading through' both LTRs in some latent cells, this does not diminish the impact of TI on the 5'LTR.NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author ManuscriptCell Host Microbe. Author manuscript; available in PMC 2014 November 03.Lenasi et al.Page
Ed cells. Furthermore, TNF- stimulation led to the appearance of Sp1 and initiating RNAPII on the 5'LTR and additional enrichments of initiating and elongating RNAPII on the 3'LTR. These effects are most likely achieved through the activation of NF-B, which stimulates several steps of viral transcription including the PIC formation, transcription initiation and transcription elongation. Thus, our
S we failed to detect any Sp1 at the PP5*/ 5'LTR junction or in the coding region of the HIV genome (Figure 5B, bars 1, 2, 5 and 6). Thus, the absence of Sp1 at the 5'LTR in untreated cells is a result of TI due to the actively transcribed PP5* gene. The finding that TNF- stimulation increased the levels of Sp1 not only at the 3' but also at the 5'LTR indicates that stimulating PIC assembly on the
Ns dormant. In contrast, we demonstrated that TI could be counteracted by specific inhibition of the upstream transcription or by cooperative activation of transcription initiation and elongation from the 5'LTR by the viral and host TFs. In the latter scenario, we envision that RNAPII initiating from the viral promoter competes successfully with the RNAPII that is elongating through the 5'LTR. Bec
Effect of Tat on transcription of the provirus. In agreement with the results in Figure 4, expression of Tat alone exerted minimal stimulatory effect on the 5'LTR (Figures 7A-7C, Tat). However, in combination with TNF-, Tat expression activated viral transcription greatly (70-80 of GFP-expressing cells) in all three cell lines (Figures 7A-7C, Tat + TNF-). We further investigated the ability of PM
Effect of Tat on transcription of the provirus. In agreement with the results in Figure 4, expression of Tat alone exerted minimal stimulatory effect on the 5'LTR (Figures 7A-7C, Tat). However, in combination with TNF-, Tat expression activated viral transcription greatly (70-80 of GFP-expressing cells) in all three cell lines (Figures 7A-7C, Tat + TNF-). We further investigated the ability of PM
Intrarectal (IR) route with 10 TCID50 of SHIVAD8-EO, in the absence of antibody treatment. As shown in Fig. 1a, plasma viremia became detectable following 2 to 6 challenges, with a median of 3.0 weekly virus exposures needed to infect all nine animals. Based on these results, the inoculum size administered to each monkey per challenge was estimated to be 0.27 AID50. The regimen used to assess the