scholarly journals A Simian Immunodeficiency Virus-Infected Macaque Model To Study Viral Reservoirs That Persist during Highly Active Antiretroviral Therapy

2009 ◽  
Vol 83 (18) ◽  
pp. 9247-9257 ◽  
Author(s):  
Jason B. Dinoso ◽  
S. Alireza Rabi ◽  
Joel N. Blankson ◽  
Lucio Gama ◽  
Joseph L. Mankowski ◽  
...  

ABSTRACT The treatment of human immunodeficiency virus type 1 (HIV-1) infection with highly active antiretroviral therapy (HAART), a combination of three or more antiretroviral drugs, suppresses viremia below the clinical limit of detection (50 HIV-1 RNA copies/ml), but latently infected resting CD4+ T cells serve as lifelong reservoirs, and low-level viremia can be detected with special assays. Recent studies have provided evidence for additional reservoirs that contribute to residual viremia but are not present in circulating cells. Identification of all the sources of residual viremia in humans may be difficult. These discoveries highlight the need for a tractable model system to identify additional viral reservoirs that could represent barriers to eradication. In this study, simian immunodeficiency virus (SIV)-infected pig-tailed macaques (Macaca nemestrina) were treated with four antiretroviral drugs to develop an animal model for viral suppression during effective HAART. Treatment led to a biphasic decay in viremia and a significant rise in levels of circulating CD4+ T cells. At terminal infection time points, the frequency of circulating resting CD4+ T cells harboring replication-competent virus was reduced to a low steady-state level similar to that observed for HIV-infected patients on HAART. The frequencies of resting CD4+ T cells harboring replication-competent virus in the pooled head lymph nodes, gut lymph nodes, spleen, and peripheral blood were reduced relative to those for untreated SIV-infected animals. These observations closely parallel findings for HIV-infected humans on suppressive HAART and demonstrate the value of this animal model to identify and characterize viral reservoirs persisting in the setting of suppressive antiretroviral drugs.

2004 ◽  
Vol 78 (17) ◽  
pp. 9105-9114 ◽  
Author(s):  
Kara G. Lassen ◽  
Justin R. Bailey ◽  
Robert F. Siliciano

ABSTRACT A stable latent reservoir for human immunodeficiency virus type 1 (HIV-1) in resting memory CD4+ T cells presents a barrier to eradication of the infection even in patients on highly active antiretroviral therapy. Potential mechanisms for latency include inaccessibility of the integrated viral genome, absence of key host transcription factors, premature termination of HIV-1 RNAs, and abnormal splicing patterns. To differentiate among these mechanisms, we isolated extremely pure populations of resting CD4+ T cells from patients on highly active antiretroviral therapy. These cells did not produce virus but retained the capacity to do so if appropriately stimulated. Products of HIV-1 transcription were examined in purified resting CD4+ T cells. Although short, prematurely terminated HIV-1 transcripts have been suggested as a marker for latently infected cells, the production of short transcripts had not been previously demonstrated in purified populations of resting CD4+ T cells. By separating RNA into polyadenylated and nonpolyadenylated fractions, we showed that resting CD4+ T cells from patients on highly active antiretroviral therapy produce abortive transcripts that lack a poly(A) tail and that terminate prior to nucleotide 181. Short transcripts dominated the pool of total HIV-1 transcripts in resting CD4+ T cells. Processive, polyadenylated HIV-1 mRNAs were also present at a low level. Both unspliced and multiply spliced forms were found. Taken together, these results show that the nonproductive nature of the infection in resting CD4+ T cells from patients on highly active antiretroviral therapy is not due to absolute blocks at the level of either transcriptional initiation or elongation but rather relative inefficiencies at multiple steps.


2006 ◽  
Vol 80 (20) ◽  
pp. 10229-10236 ◽  
Author(s):  
Pierre Delobel ◽  
Marie-Thérèse Nugeyre ◽  
Michelle Cazabat ◽  
Karine Sandres-Sauné ◽  
Christophe Pasquier ◽  
...  

ABSTRACT The reasons for poor CD4+ T-cell recovery in some human immunodeficiency virus (HIV)-infected subjects despite effective highly active antiretroviral therapy (HAART) remain unclear. We recently reported that CXCR4-using (X4) HIV-1 could be gradually selected in cellular reservoirs during sustained HAART. Because of the differential expression of HIV-1 coreceptors CCR5 and CXCR4 on distinct T-cell subsets, the residual replication of R5 and X4 viruses could have different impacts on T-cell homeostasis during immune reconstitution on HAART. We examined this hypothesis and the mechanisms of CD4+ T-cell restoration by comparing the virological and immunological features of 15 poor and 15 good immunological responders to HAART. We found a high frequency of X4 viruses in the poor immunological responders. But the levels of intrathymic proliferation of the two groups were similar regardless of whether they were infected by R5 or X4 virus. The frequency of recent thymic emigrants in the poor immunological responders was also similar to that found in the good immunological responders, despite their reduced numbers of naïve CD4+ T cells. Our data, rather, suggest that the naïve T-cell compartment is drained by a high rate of mature naïve cell loss in the periphery due to bystander apoptosis or activation-induced differentiation. X4 viruses could play a role in the depletion of naïve T cells in poor immunological responders to HAART by triggering persistent T-cell activation and bystander apoptosis via gp120-CXCR4 interactions.


2002 ◽  
Vol 76 (2) ◽  
pp. 707-716 ◽  
Author(s):  
Tuofu Zhu ◽  
David Muthui ◽  
Sarah Holte ◽  
David Nickle ◽  
Feng Feng ◽  
...  

ABSTRACT In vitro studies show that human immunodeficiency virus type 1 (HIV-1) does not replicate in freshly isolated monocytes unless monocytes differentiate to monocyte-derived macrophages. Similarly, HIV-1 may replicate in macrophages in vivo, whereas it is unclear whether blood monocytes are permissive to productive infection with HIV-1. We investigated HIV-1 replication in CD14+ monocytes and resting and activated CD4+ T cells by measuring the levels of cell-associated viral DNA and mRNA and the genetic evolution of HIV-1 in seven acutely infected patients whose plasma viremia had been <100 copies/ml for 803 to 1,544 days during highly active antiretroviral therapy (HAART). HIV-1 DNA was detected in CD14+ monocytes as well as in activated and resting CD4+ T cells throughout the course of study. While significant variation in the decay slopes of HIV-1 DNA was seen among individual patients, viral decay in CD14+ monocytes was on average slower than that in activated and resting CD4+ T cells. Measurements of HIV-1 sequence evolution and the concentrations of unspliced and multiply spliced mRNA provided evidence of ongoing HIV-1 replication, more pronounced in CD14+ monocytes than in resting CD4+ T cells. Phylogenetic analyses of HIV-1 sequences indicated that after prolonged HAART, viral populations related or identical to those found only in CD14+ monocytes were seen in plasma from three of the seven patients. In the other four patients, HIV-1 sequences in plasma and the three cell populations were identical. CD14+ monocytes appear to be one of the potential in vivo sources of HIV-1 in patients receiving HAART.


2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Vitus Sambo Badii ◽  
Kwame Ohene Buabeng ◽  
Thomas Agyarko Poku ◽  
Arnold Donkor Forkuo ◽  
Bright Boafo Boamah ◽  
...  

Tenofovir-based highly active antiretroviral therapy (HAART) is one of the preferred first-line therapies in the management of HIV 1 infection. Ghana has since 2014 adopted this recommendation; however there is paucity of scientific data that reflects the safety and efficacy of the tenofovir-based therapy compared to zidovudine in the Ghanaian health system. This study sought to assess the comparative immune reconstitution potential between tenofovir and zidovudine-based HAART regimens, which includes lamivudine and efavirenz in combination therapy. It also aimed to investigate the adverse drug reactions/events (ADREs) associated with pharmacotherapy with these agents in a total of 106 HAART naïve HIV patients. The study included 80 patients in the tenofovir cohort while 26 patients were on the zidovudine regimen. The occurrence of HIV comorbidities profile was assessed at diagnosis and throughout the study period. The baseline CD4 T cells count of the participants was also assessed at diagnosis and repeated at a median period of five months (range 4–6 months), after commencing treatment with either tenofovir- or zidovudine-based HAART. After five months of the HAART, the tenofovir cohort recorded higher CD4 T cell count change from baseline compared to the zidovudine cohort (p<0.0001). The patients on the tenofovir-based HAART and female sex however appeared to be associated with more multiple ADREs.


2004 ◽  
Vol 11 (5) ◽  
pp. 957-962 ◽  
Author(s):  
Thomas W. McCloskey ◽  
Viraga Haridas ◽  
Lucy Pontrelli ◽  
Savita Pahwa

ABSTRACT Our understanding of the pathogenesis of perinatal human immunodeficiency virus (HIV) infection is still evolving. We sought to characterize the response to the bacterial superantigen Staphylococcus enterotoxin B (SEB) of lymphocytes from HIV-infected children receiving treatment with highly active antiretroviral therapy (HAART). Using the flow cytometric methodology, we quantified apoptosis, proliferation, cytokine production, and activation antigen upregulation in CD4 and CD8 T lymphocytes following in vitro stimulation of peripheral blood mononuclear cells (PBMCs) with SEB. The levels of proliferation, CD4 interleukin-2 (IL-2) production, CD8 gamma interferon (IFN-γ) production, and upregulation of CD69 expression by cells from HIV-infected children were indistinguishable from those by cells from controls. However, stimulation with SEB dramatically decreased the ratio of resting apoptotic cells to cycling apoptotic cells in the controls but not in the patients. In addition, unstimulated spontaneous apoptosis of CD4 T cells remained greater in the patients than in the controls. The percentages of IL-2-positive CD8 T cells and IFN-γ-positive CD4 T cells following SEB stimulation were significantly lower in the patients than in the controls. Our multiparameter approach was able to demonstrate differences in lymphocyte superantigen responsiveness in HIV-infected children receiving HAART in comparison to that in uninfected controls, notably, an apoptotic versus a proliferative response to stimulation.


2001 ◽  
Vol 27 (2) ◽  
pp. 105-115 ◽  
Author(s):  
Janet K. A. Nicholson ◽  
Sandra W. Browning ◽  
Richard L. Hengel ◽  
Edward Lew ◽  
Laura E. Gallagher ◽  
...  

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