RNA Plasma Viral Load Research Articles

Factors associated with the failure of first and second-line antiretroviral therapies therapy, a case control study in Cambodian HIV-1 infected children.

BackgroundLittle is known about the efficacy of first and and second-line antiretroviral therapies (ART) for HIV-1 infected children in resource limited Southeast Asian settings. Previous studies have shown that orphans are at a higher risk for virological failure (VF) in Cambodia. Consequently most of them required transfer to second-line ART. We assessed the factors associated with VF among HIV-1 infected children who were either under first-line (mostly 3TC + D4T + NVP) or under second-line (mostly ABC + DDI + LPV) therapies at a referral hospital in Cambodia.MethodsA case-control study was conducted from February to July 2013 at the National Pediatric Hospital among HIV-1 infected children (aged 1–15 years) under second-line ART (cases) or first-line (matched controls at a ratio of 1:3) regimens. Children were included if a HIV-1 RNA plasma viral load (VL) result was available for the preceding 12 months. A standardized questionnaire explored family sociodemographics, HIV history, and adherence to ART. Associations between VF (HIV-1 RNA levels ≥1000 copies/ml) and the children’s characteristics were assessed using bivariate and multivariate analyses.ResultsA total of 232 children, 175 (75.4 %) under first-line and 57 (24.6 %) under second-line ART, for a median of 72.0 (IQR: 68.0–76.0) months, were enrolled. Of them, 94 (40.5 %) were double orphans and 51 (22.0 %) single orphans, and 77 (33.2 %) were living in orphanages. A total of 222 children (95.6 %) were deemed adherent to ART. Overall, 18 (7.7 %; 95 % CI 4.6–11.9) showed a VF, 14 (8.6 %; 95 % CI 4.8–14.0) under first-line and 4 (7.0 %; 95 % CI 1.9–17.0) under second-line ART (p = 0.5). Their median CD4 percentage was 8 % (IQR 2.9–12.9) at ART initiation. Children under second-line ART were older; more often double orphans, and had lower CD4 cell counts at the last control.In the multivariate analysis, having the last CD4 percentage below 15 % was the only factor associated with VF for ART regimen separately or when combined (OR 40.4; 95 % CI 11–134).ConclusionsThe pattern of risk factors for VF in children is changing in Cambodia. Improved adherence evaluation and intensified monitoring of children with low CD4 counts is needed to decrease the risk of VF.Electronic supplementary materialThe online version of this article (doi:10.1186/s13104-016-1884-y) contains supplementary material, which is available to authorized users.

Persistent replication of a hepatitis C virus genotype 1b-based chimeric clone carrying E1, E2 and p6 regions from GB virus B in a New World monkey.

The development of effective hepatitis C virus (HCV) vaccines is essential for the prevention of further HCV dissemination, especially in developing countries. Therefore the aim of this study is to establish a feasible and immunocompetent surrogate animal model of HCV infection that will help in evaluation of the protective efficacy of newly developing HCV vaccine candidates. To circumvent the narrow host range of HCV, an HCV genotype 1b-based chimeric clone carrying E1, E2 and p6 regions from GB virus B (GBV-B), which is closely related to HCV, was generated. The chimera between HCV and GBV-B, named HCV/G, replicated more efficiently as compared with the HCV clone in primary marmoset hepatocytes. Furthermore, it was found that the chimera persistently replicated in a tamarin for more than 2 years after intrahepatic inoculation of the chimeric RNA. Although relatively low (<200 copies/mL), the viral RNA loads in plasma were detectable intermittently during the observation period. Of note, the chimeric RNA was found in the pellet fraction obtained by ultracentrifugation of the plasma at 73 weeks, indicating production of the chimeric virus. Our results will help establish a novel non-human primate model for HCV infection on the basis of the HCV/G chimera in the major framework of the HCV genome.

Exposure to SIV in utero results in reduced viral loads and altered responsiveness to postnatal challenge.

HIV disease progression appears to be driven by increased immune activation. Given observations that fetal exposure to infectious pathogens in utero can result in reduced immune responses, or tolerance, to those pathogens postnatally, we hypothesized that fetal exposure to HIV may render the fetus tolerant to the virus, thus reducing damage caused by immune activation during infection later in life. To test this hypothesis, fetal rhesus macaques (Macaca mulatta) were injected with the attenuated virus SIVmac1A11 in utero and challenged with pathogenic SIVmac239 1 year after birth. SIVmac1A11-injected animals had significantly reduced plasma RNA viral loads (P < 0.02) up to 35 weeks after infection. Generalized estimating equations analysis was performed to identify immunologic and clinical measurements associated with plasma RNA viral load. A positive association with plasma RNA viral load was observed with the proportion of CD8(+) T cells expressing the transcription factor, FoxP3, and the proportion of CD4(+) T cells producing the lymphoproliferative cytokine, IL-2. In contrast, an inverse relationship was found with the frequencies of circulating CD4(+) and CD8(+) T cells displaying intermediate expression of the proliferation marker, Ki-67. Animals exposed to simian immunodeficiency virus (SIV) in utero appeared to have enhanced SIV-specific immune responses, a lower proportion of CD8(+) T cells expressing the exhaustion marker PD-1, and more circulating TH17 cells than controls. Although the development of tolerance was not demonstrated, these data suggest that rhesus monkeys exposed to SIVmac1A11 in utero had distinct immune responses associated with the control of viral replication after postnatal challenge.

A TYPICAL EXTENSIVE GENITAL ULCER IN FULL BLOWN AIDS WITH SLIM DISEASE

Background : Atypical and exceptional clinical presentation of full blown AIDS may be observed in sub-Saharan Africa. We report herein the case of a Central African 37-year-old male patient presented with full blown AIDS, a typical picture of slim disease with marked cachexia and wasting faces. In addition, the patient was suffering from very extensive genital ulcer with complete loss of substance of the genitalia. Methods : Extensive histological and microbiological analysis of the genital lesion was carried out. Results : HIV-1 serology was positive, the HIV-1 RNA plasma viral load was 5.3 log copies/ml and CD4 T cell count was 1 per μL. Search for Mycobacterium tuberculosis in sputum and urine was negative by direct microscopic examination with Ziehl-Neelsen staining. Testing for syphilis serology was negative. Direct immunofluorescence detection on genital ulcer scraping was negative for Chlamydia trachomatis and Treponema pallidum . Furthermore, the infections with Haemophilus ducreyi and Chlamydia trachomatis were excluded by PCR on genital swabs.Genital PCR was positive for herpes simplex virus (HSV) type 2. Marked improvement was observed within 6 weeks after starting empirical therapy including first-line antiretroviral therapy, cotrimoxazole, doxycycline and valacyclovir, with progressive healing of genital ulcer and negativity of HSV PCR. Conclusion : Taken together, the extensive genital ulcer in this patient is likely the result of a multifactorial process, involving both profound cellular immune depression and complex genital infectious process in which herpetic infection may have participated as a chronic worsening co-factor. Key words : Slim disease, HIV, Extensive genital ulcer, Herpes simplex virus type 2.

Correlation of central memory CD4+ T-Cell decrease in the peripheral blood with disease progression in SIVmac251-infected Chinese rhesus macaques.

Correlation of CD4(+) Tcm cells in the peripheral blood to disease progression in SIVmac251 infection was examined in Chinese rhesus macaques. Plasma viral RNA loads were measured by a quantitative real-time reverse transcription-PCR (qRT-PCR) assay for SIV gag. Disease progression was determined based on time of survival. Phenotyping of CD4(+) T-cell subsets in the peripheral blood was longitudinally performed by flow cytometry. Although CD4(+) T-cell decrease and low CD4(+)/CD8(+) T-cell ratio in the peripheral blood after SIVmac251 infection did not correlate with disease progression, CD4(+) Tcm cell decrease was observed to be correlated to disease progression in the SIVmac251-infected Chinese rhesus macaques. Our findings suggest that CD4(+) Tcm cell decrease could be used as a predictive marker for defining the pathogenesis of the SIV disease and consequently HIV/SIV vaccine efficacy in Chinese rhesus macaques.

No benefit of therapeutic vaccination in clinically healthy cats persistently infected with feline leukemia virus

Therapeutic vaccinations have a potential application in infections where no curative treatment is available. In contrast to HIV, efficacious vaccines for a cat retrovirus, feline leukemia virus (FeLV), are commercially available. However, the infection is still prevalent, and no effective treatment of the infection is known. By vaccinating persistently FeLV-infected cats and presenting FeLV antigens to the immune system of the host, e.g., in the form of recombinant and/or adjuvanted antigens, we intended to shift the balance toward an advantage of the host so that persistent infection could be overcome by the infected cat. Two commercially available FeLV vaccines efficacious in protecting naïve cats from FeLV infection were tested in six experimentally and persistently FeLV-infected cats: first, a canarypox-vectored vaccine, and second, an adjuvanted, recombinant envelope vaccine was repeatedly administered with the aim to stimulate the immune system. No beneficial effects on p27 antigen and plasma viral RNA loads, anti-FeLV antibodies, or life expectancy of the cats were detected. The cats were unable to overcome or decrease viremia. Some cats developed antibodies to FeLV antigens although not protective. Thus, we cannot recommend vaccinating persistently FeLV-infected cats as a means of improving their FeLV status, quality of life or life expectancy. We suggest testing of all cats for FeLV infection prior to FeLV vaccination.

Evaluation of the effect of short-term treatment with the integrase inhibitor raltegravir (Isentress™) on the course of progressive feline leukemia virus infection

Cats persistently infected with the gammaretrovirus feline leukemia virus (FeLV) are at risk to die within months to years from FeLV-associated disease, such as immunosuppression, anemia or lymphoma/leukemia. The integrase inhibitor raltegravir has been demonstrated to reduce FeLV replication in vitro. The aim of the present study was to investigate raltegravir in vivo for its safety and efficacy to suppress FeLV replication. The safety was tested in three naïve specified pathogen-free (SPF) cats during a 15 weeks treatment period (initially 20mg then 40mg orally b.i.d.). No adverse effects were noted. The efficacy was tested in seven persistently FeLV-infected SPF cats attained from 18 cats experimentally exposed to FeLV-A/Glasgow-1. The seven cats were treated during nine weeks (40mg then 80mg b.i.d.). Raltegravir was well tolerated even at the higher dose. A significant decrease in plasma viral RNA loads (∼5×) was found; however, after treatment termination a rebound effect was observed. Only one cat developed anti-FeLV antibodies and viral RNA loads remained decreased after treatment termination. Of note, one of the untreated FeLV-A infected cats developed fatal FeLV-C associated anemia within 5 weeks of FeLV-A infection. Moreover, progressive FeLV infection was associated with significantly lower enFeLV loads prior to infection supporting that FeLV susceptibility may be related to the genetic background of the cat. Overall, our data demonstrate the ability of raltegravir to reduce viral replication also in vivo. However, no complete control of viremia was achieved. Further investigations are needed to find an optimized treatment against FeLV. (250 words)

Association between feline immunodeficiency virus (FIV) plasma viral RNA load, concentration of acute phase proteins and disease severity

Veterinarians have few tools to predict the rate of disease progression in FIV-infected cats. In contrast, in HIV infection, plasma viral RNA load and acute phase protein concentrations are commonly used as predictors of disease progression. This study evaluated these predictors in cats naturally infected with FIV. In older cats (>5 years), log10 FIV RNA load was higher in the terminal stages of disease compared to the asymptomatic stage. There was a significant association between log10 FIV RNA load and both log10 serum amyloid A concentration and age in unwell FIV-infected cats. This study suggests that viral RNA load and serum amyloid A warrant further investigation as predictors of disease status and prognosis in FIV-infected cats.

Effect of semen and seminal amyloid on vaginal transmission of simian immunodeficiency virus

BackgroundSemen and semen-derived amyloid fibrils boost HIV infection in vitro but their impact on sexual virus transmission in vivo is unknown. Here, we examined the effect of seminal plasma (SP) and semen-derived enhancer of virus infection (SEVI) on vaginal virus transmission in the SIV/rhesus macaque (Macacca mulatta) model.ResultsA total of 18 non-synchronized female rhesus macaques (six per group) were exposed intra-vaginally to increasing doses of the pathogenic SIVmac239 molecular clone in the presence or absence of SEVI and SP. Establishment of productive virus infection was assessed by measuring plasma viral RNA loads at weekly intervals. We found that the first infections occurred at lower viral doses in the presence of SP and SEVI compared to the control group. Furthermore, the average peak viral loads during acute infection were about 6-fold higher after exposure to SP- and SEVI-treated virus. Overall infection rates after a total of 27 intra-vaginal exposures to increasing doses of SIV, however, were similar in the absence (4 of 6 animals) and presence of SP (5 of 6), or SEVI (4 of 6). Furthermore, the infectious viral doses required for infection varied considerably and did not differ significantly between these three groups.ConclusionsSemen and SEVI did not have drastic effects on vaginal SIV transmission in the present experimental setting but may facilitate spreading of virus infection after exposure to low viral doses that most closely approximate the in vivo situation.

Understanding HIV epidemics

Powers et al. [1] provide valuable, thoughtful and thought provoking comments on our study [2]. In their first comment, they urge movement toward consistent, standardized definitions for specific aggregate viral load measures. We agree with this call. Furthermore, we believe this is timely with the increasing availability of HIV-1 plasma RNA viral load data for large subpopulations, and the growing role of viral load for clinical monitoring. We also acknowledge that our definition for community viral load in terms of all antiretroviral therapy (ART)-naive people with available viral load is different from the definition of the Centers for Disease Control and Prevention (CDC) that includes both untreated and treated HIV-infected people [3]. This operational definition, however, reflects our interest in examining the potential role of other factors such as coinfections in the HIV epidemic potential of populations in different regions around the world. Different viral load measures (including those articulated in the CDC guidance – population viral load, community viral load, in-care viral load, and monitored viral load) are useful to assess different questions and have different levels of feasibility [3]. For example, although population viral load is probably the optimal measure of ongoing epidemic potential, it is not possible to measure it in most settings because it includes undiagnosed HIV infection. At the other end of the continuum in the CDC guidance, monitored viral load is relatively easy to assess, and is informative with respect to quality of care, but may covey little about transmission potential at the population level. We appreciate Powers et al.[1] suggestion of including explicitly specific assumptions in such analyses of viral load data. We implicitly assumed in our study that, biologically, HIV natural history, for ART-naive persons, has not changed throughout the epidemic. As noted in our study, we also agree that there could be factors, known or unknown, that could affect viral load measurements throughout the epidemic, and for which we were unable to control. Nevertheless, we did attempt to control for the differences in the distribution of HIV-infected persons across the different HIV stages by controlling for CD4 categories. We also concur with Powers’ et al.[1] concern about the use of the term ‘driving force.’ Causal attribution of factors within epidemics is an issue of intense discussion. We wish to clarify here that we used a stringent and conservative definition for attribution, based on the number of infections directly caused by heightened viral load, rather than those based on an estimate of the direct and indirect effects of heightened viral load. Including indirect effects, such as those due to onward transmission, would have even resulted in a considerably larger attributable role for heightened viral load. Powers and colleagues, both here and elsewhere [4,5] have highlighted critical issues that must be dealt with to assess the role of viral load in HIV transmission. These issues are particularly timely given recent progress in HIV research, and the availability of a growing array of efficacious interventions to prevent HIV transmission by suppressing the viral load [5]. Our study reinforces the importance of these issues by suggesting that differences in viral load in ART-naive populations may have played a key role in shaping the different epidemic trajectories that we see across regions around the globe today. Acknowledgements Conflicts of interest There are no conflicts of interest.

Cellular HIV Type 1 DNA Levels Are Equivalent Among Drug-Sensitive and Drug-Resistant Strains in Newly Diagnosed and Antiretroviral Naive Patients

The emergence of resistance against current antiretroviral drugs to human immunodeficiency virus type 1 (HIV-1) is an increasingly important concern to the continuous success of antiretroviral therapy to HIV-1-infected patients. In the past decade, a number of studies reported that the prevalence of transmitted drug resistance among newly diagnosed patients has reached an overall 9% prevalence worldwide. Also, a number of studies using longitudinal HIV-1 patient study cohorts demonstrated that the cellular HIV-1 DNA level in peripheral blood mononuclear cells (PBMCs) has a prognostic value for the progression of HIV-1 disease independently of plasma HIV-1 RNA load and CD4 count. Using a previously established molecular-beacon-based real-time PCR methodology, cellular HIV-1 DNA levels were quantified in newly diagnosed and antiretroviral-naive patients in Northern Greece recruited between 2009 and 2010 using a predefined enrolling strategy, in an effort to investigate whether there is any relationship between cellular HIV-1 DNA levels and HIV-1 transmitted drug resistance. As part of the same study, DNA sequences encoding the env (C2-C5 region of gp120) were also amplified from PBMC-extracted DNA in order to determine the genotypic coreceptor tropism and genetic subtype. Cellular HIV-1 DNA levels had a median of 3.309 log10 HIV-1 copies per 10(6) PBMCs and demonstrated no correlation between cellular HIV-1 DNA levels and HIV-1 transmitted drug resistance. An absence of association between cellular HIV-1 DNA levels with plasma viral HIV-1 RNA load and CD4 levels was also found reconfirming the previously published study. Genotypic analysis of coreceptor tropism indicated that 96% of samples, independently of the presence or not of genotypic drug resistance, were CCR5-tropic. Overall, the findings reconfirmed the previously proposed proposition that transmitted drug resistance does not have an impact on disease progression in HIV-1-infected individuals. Also, CCR5 coreceptor tropism dominance suggests that both drug-resistant and drug-sensitive strains behave similarly in early infection in newly diagnosed patients.

Efficacité et tolérance d’une trithérapie antirétrovirale à base de ténofovir disoproxil-emtricitabine-éfavirenz chez les patients naïfs infectés par le VIH-1 à Bobo Dioulasso (Burkina Faso, 2009–2011)

The objective of this study was to evaluate the effectiveness and the clinical tolerance of a combination containing TDF/FTC/EFV in the treatment of HIV infection. This was a retrospective and descriptive study which included 196 adults infected by HIV-1 and treated by a combination containing TDF/FTC/EFV during 29 months in the daily hospital of Bobo Dioulasso. The median duration of follow-up was 7 months IQR [5-14 month]. The median age was 37 years IQR [31-45].With the initiation of treatment ARV, the median of the index of body mass was of 19 IQR [17-22]. The median of the lymphocytes TCD4 was 201/μl IQR [74-298/μl]. During the follow-up, we reported 25 deaths (12.8%). HIV-1 RNA plasma viral load was undetectable in 91.9% of the patients (124/135) at six months of treatment. The majority of the adverse effects of the treatment were of a neurosensory nature (40.5%). The TDF/FTC/EFV combination showed a good effectiveness in the treatment of the infection with HIV-1 in the first intention just as a good clinical tolerance.

HIV-1 outcompetes HIV-2 in dually infected Senegalese individuals with low CD4⁺ cell counts.

Dual infection with HIV-1 and HIV-2, which is not uncommon in West Africa, has implications for transmission, progression, and antiretroviral therapy (ART). Few studies have examined viral dynamics in this setting. Our objective was to directly compare HIV-1 and HIV-2 viral loads and to examine whether this relationship is associated with CD4⁺ cell count. This is a retrospective analysis of data from observational cohort studies. We compared HIV-1 and HIV-2 viral loads from 65 dually infected, ART-naive Senegalese individuals. Participants provided blood, oral fluid, and cervicovaginal lavage (CVL) or semen samples for virologic and immunologic testing. We assessed relationships between HIV-1 and HIV-2 levels using linear regression with generalized estimating equations to account for multiple study visits. After adjusting for CD4⁺ cell count, age, sex, and commercial sex work, HIV-1 RNA levels were significantly higher than HIV-2 levels in semen, CVL, and oral fluids. Despite similar peripheral blood mononuclear cell DNA levels among individuals with CD4⁺ cell counts above 500 cells/μl, individuals with CD4⁺ cell counts below 500 cells/μl had higher HIV-1 and lower HIV-2 DNA levels. Individuals with high CD4⁺ cell counts had higher mean HIV-1 plasma RNA viral loads than HIV-2, with HIV-1 levels significantly higher and HIV-2 levels trending toward lower mean viral loads among individuals with low CD4⁺ cell counts. Our data are consistent with the hypothesis that with disease progression, HIV-1 outcompetes HIV-2 in dually infected individuals. This finding helps explain differences in prevalence and outcomes between HIV-1, HIV-2, and HIV-dual infection.

Have the explosive HIV epidemics in sub-Saharan Africa been driven by higher community viral load?

The HIV epidemic has carved contrasting trajectories around the world with sub-Saharan Africa (SSA) being most affected. We hypothesized that mean HIV-1 plasma RNA viral loads are higher in SSA than other areas, and that these elevated levels may contribute to the scale of epidemics in this region.To evaluate this hypothesis, we constructed a database of means of 71,668 viral load measurements from 44 cohorts in seven regions of the world. We used linear regression statistical models to estimate differences in viral load between regions. We also constructed and analyzed a mathematical model to describe the impact of the regional viral load differences on HIV epidemic trajectory.We found substantial regional viral load heterogeneity. The mean viral load in SSA was 0.58 log(10) copies/ml higher than in North America (95% confidence interval 0.45-0.71); this represents about a four-fold increase. The highest mean viral loads were found in Southern and East Africa, whereas in Asia, Europe, North America, and South America, mean viral loads were comparable. Mathematical modeling indicated that conservatively 14% of HIV infections in a representative population in Kenya could be attributed to the enhanced infectiousness of patients with heightened viral load.We conclude that community viral load appears to be higher in SSA than in other regions and this may be a central driver of the massive HIV epidemics in this region. The elevated viral loads in SSA may reflect, among other factors, the high burden of co-infections or the preponderance of HIV-1 subtype C infection.

HIV-DNA in the Genital Tract of Women on Long-Term Effective Therapy Is Associated to Residual Viremia and Previous AIDS-Defining Illnesses

ObjectivesTo assess the impact of long-term combined antiretroviral therapy (cART) on HIV-RNA and HIV-DNA levels in cervicovaginal secretions of HIV-1-infected women with sustained undetectable plasma RNA viral load (PVL); to explore factors predictive of residual viral shedding; and to evaluate the risk of heterosexual transmission.MethodsWomen with undetectable PVL (<50 copies/mL) for >6 months were included in this cross-sectional study. HIV-RNA and HIV-DNA were measured in blood and cervicovaginal lavage fluid (CVL). Women were systematically tested for genital infections. The risk of transmission to male partners during unprotected intercourse was estimated.ResultsEighty-one women composed the study population: all had HIV-RNA <40 copies/mL in CVL. HIV-DNA was detectable in CVL of 29/78 patients (37%). There was a weak positive correlation between HIV-DNA levels in PBMCs and CVL (r = 0.20; p = 0.08). In multivariate analysis, two factors were associated with HIV-DNA detection in CVL: previous AIDS-defining illnesses (OR = 11; 95%CI = 2–61) and current residual viremia (20<PVL<50 cp/mL) (OR = 3.4; 95%CI = 1.1–10.9). Neither the classes of cART regimen nor the presence of genital bacterial or fungal colonization were associated with HIV-DNA detection in CVL. Twenty-eight percent of the women had unprotected intercourse with their regular HIV-seronegative male partner, for between 8 and 158 months. None of their male partners became infected, after a total of 14 000 exposures.ConclusionIn our experience, HIV-RNA was undetectable in the genital tract of women with sustained control of PVL on cART. HIV-DNA shedding persisted in about one third of cases, with no substantial evidence of residual infectiousness.

Short Communication: HIV Blips While on Antiretroviral Therapy Can Indicate Consistently Detectable Viral Levels Due to Assay Underreporting

Viral blips, where HIV RNA plasma viral load (pVL) intermittently increases above the lower limit of assay detection, are a cause for concern. We investigated a number of hypotheses for their cause. We assessed HIV RNA, and total and episomal HIV DNA from 16 individuals commencing antiretroviral therapy (ART) consisting of raltegravir and tenofovir/emtricitabine for 3 years, using two assays: a single-copy assay [SCA; lower limit of quantification (LLOQ), <1 copy/ml] and the Amplicor assay (LLOQ of 50 copies/ml). Two individuals exhibited viral blips. From week 20 onward, the period where ART had achieved its final suppressive levels, pVL ranged from <1 to 330 copies/ml, except for one individual at the final time. Both assays were 98% consistent (108/110) in assessing pVL <50 copies/ml, but the Amplicor assay registered 56% of samples (19/34) as below the LLOQ that were in the 50 to 1000 copy/ml range as quantified by SCA. pVL changes between successive time points did not correlate with changes in cellular infection as measured through either total or episomal HIV DNA. Changes in pVL were correlated (negatively) with changes in total CD4(+) T cell numbers (p=0.003), naive (CD45RO(-)CD62L(+)CD4(+)), natural regulatory (CD45RO(-)CD25(+)CD127(-)CD4(+)), activated effector (CD45RO(+)CD38(++)CCR5(+)CD8(+)), but not activated (CD38(+)HLA-DR(+)) CD4(+) T cells. Patients receiving stable, seemingly suppressive ART can have pVL near the 50 copy LLOQ at multiple time points. The high Amplicor assay error rate around this level implies that viral blips underrepresent pVL being more consistently above the LLOQ. Activation of latently infected cells is less likely to contribute to this phenomenon.

Have the explosive HIV epidemics in sub-Saharan Africa been driven by higher community viral load?

The HIV epidemic has carved contrasting trajectories around the world with sub-Saharan Africa (SSA) being most affected. We hypothesized that mean HIV-1 plasma RNA viral loads are higher in SSA than other areas, and that these elevated levels may contribute to the scale of epidemics in this region. To evaluate this hypothesis, we constructed a database of means of 71,668 viral load measurements from 44 cohorts in seven regions of the world. We used linear regression statistical models to estimate differences in viral load between regions. We also constructed and analyzed a mathematical model to describe the impact of the regional viral load differences on HIV epidemic trajectory. We found substantial regional viral load heterogeneity. The mean viral load in SSA was 0.58 log(10) copies/ml higher than in North America (95% confidence interval 0.45-0.71); this represents about a four-fold increase. The highest mean viral loads were found in Southern and East Africa, whereas in Asia, Europe, North America, and South America, mean viral loads were comparable. Mathematical modeling indicated that conservatively 14% of HIV infections in a representative population in Kenya could be attributed to the enhanced infectiousness of patients with heightened viral load. We conclude that community viral load appears to be higher in SSA than in other regions and this may be a central driver of the massive HIV epidemics in this region. The elevated viral loads in SSA may reflect, among other factors, the high burden of co-infections or the preponderance of HIV-1 subtype C infection.

Predictive Factors of Plasma HIV Suppression during Pregnancy: A Prospective Cohort Study in Benin

ObjectiveTo investigate the factors associated with HIV1 RNA plasma viral load (pVL) below 40 copies/mL at the third trimester of pregnancy, as part of prevention of mother-to-child transmission (PMTCT) in Benin.DesignSub study of the PACOME clinical trial of malaria prophylaxis in HIV-infected pregnant women, conducted before and after the implementation of the WHO 2009 revised guidelines for PMTCT.MethodsHIV-infected women were enrolled in the second trimester of pregnancy. Socio-economic characteristics, HIV history, clinical and biological characteristics were recorded. Malaria prevention and PMTCT involving antiretroviral therapy (ART) for mothers and infants were provided. Logistic regression helped identifying factors associated with virologic suppression at the end of pregnancy.ResultsOverall 217 third trimester pVLs were available, and 71% showed undetectability. Virologic suppression was more frequent in women enrolled after the change in PMTCT recommendations, advising to start ART at 14 weeks instead of 28 weeks of pregnancy. In multivariate analysis, Fon ethnic group (the predominant ethnic group in the study area), regular job, first and second pregnancy, higher baseline pVL and impaired adherence to ART were negative factors whereas higher weight, higher antenatal care attendance and longer ART duration were favorable factors to achieve virologic suppression.ConclusionsThis study provides more evidence that ART has to be initiated before the last trimester of pregnancy to achieve an undetectable pVL before delivery. In Benin, new recommendations supporting early initiation were well implemented and, together with a high antenatal care attendance, led to high rate of virologic control.

Impact of Use of Alcohol and Illicit Drugs by AIDS Patients on Adherence to Antiretroviral Therapy in Bahia, Brazil

Use of alcohol and illicit drugs is a common finding among HIV-infected individuals, but there are many open questions about its impact on adherence to antiretroviral therapy and virological outcomes. Our study aimed to evaluate the impact of the use of alcohol and illicit drugs on the adherence to antiretroviral therapy (ART) among patients starting ART in Salvador, Brazil. We followed up 144 AIDS patients initiating ART for a 6-month period. At baseline, they were interviewed about demographics, behavior, and use of illicit drugs and alcohol. All of them had HIV-1 RNA plasma viral load and CD4(+)/CD8(+) cells count measured before starting therapy. After 60 days of treatment they were asked to answer a new questionnaire on adherence to ART. All patients were monitored during the following months, and new CD4(+) cell count/HIV-1 RNA plasma viral load determinations were performed after 6 months of therapy. Optimal adherence to therapy was defined by self-reported questionnaire, by 95% use of prescribed drug doses, and by using plasma HIV-1 RNA viral load as a biological marker. A total of 61 (42.4%) patients reported alcohol use, 7 (4.9%) used illicit drugs, and 17 (11.8%) used both alcohol and illicit drugs. Being in a steady relationship was protective to nonadherence (95% CI: 0.18-0.84). Missing more than two medical visits was also associated with a 68% higher likelihood of nonadherence (95% CI: 0.10-1.02). After logistic regression we detected a higher risk of nonadherence for patients declaring use of alcohol plus illicit drugs (odds ratio=6.0; 95% CI: 1.78-20.28) or high-intensity use of alcohol (odds ratio=3.29; 95% CI: 1.83-5.92). AIDS patients using alcohol and/or illicit drugs are socially vulnerable, and need specific and flexible programs, combining mental health care, harm reduction strategies, and assisted drug therapy to maximize the chances of successful use of ART.

Site-specific Genome Editing in PBMCs With PLGA Nanoparticle-delivered PNAs Confers HIV-1 Resistance in Humanized Mice

Biodegradable poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) encapsulating triplex-forming peptide nucleic acids (PNAs) and donor DNAs for recombination-mediated editing of the CCR5 gene were synthesized for delivery into human peripheral blood mononuclear cells (PBMCs). NPs containing the CCR5-targeting molecules efficiently entered PBMCs with low cytotoxicity. Deep sequencing revealed that a single treatment with the formulation resulted in a targeting frequency of 0.97% in the CCR5 gene and a low off-target frequency of 0.004% in the CCR2 gene, a 216-fold difference. NP-treated PBMCs efficiently engrafted immunodeficient NOD-scid IL-2rγ-/- mice, and the targeted CCR5 modification was detected in splenic lymphocytes 4 weeks posttransplantation. After infection with an R5-tropic strain of HIV-1, humanized mice with CCR5-NP–treated PBMCs displayed significantly higher levels of CD4+ T cells and significantly reduced plasma viral RNA loads compared with control mice engrafted with mock-treated PBMCs. This work demonstrates the feasibility of PLGA-NP–encapsulated PNA-based gene-editing molecules for the targeted modification of CCR5 in human PBMCs as a platform for conferring HIV-1 resistance.