Antiretroviral therapy alone versus antiretroviral therapy with a kick and kill approach, on measures of the HIV reservoir in participants with recent HIV infection (the RIVER trial): a phase 2, randomised trial.

BACKGROUND: Antiretroviral therapy (ART) cannot cure HIV infection because of a persistent reservoir of latently infected cells. Approaches that force HIV transcription from these cells, making them susceptible to killing-termed kick and kill regimens-have been explored as a strategy towards an HIV cure. RIVER is the first randomised trial to determine the effect of ART-only versus ART plus kick and kill on markers of the HIV reservoir. METHODS: This phase 2, open-label, multicentre, randomised, controlled trial was undertaken at six clinical sites in the UK. Patients aged 18-60 years who were confirmed as HIV-positive within a maximum of the past 6 months and started ART within 1 month from confirmed diagnosis were randomly assigned by a computer generated randomisation list to receive ART-only (control) or ART plus the histone deacetylase inhibitor vorinostat (the kick) and replication-deficient viral vector T-cell inducing vaccines encoding conserved HIV sequences ChAdV63. HIVconsv-prime and MVA.HIVconsv-boost (the kill; ART + V + V; intervention). The primary endpoint was total HIV DNA isolated from peripheral blood CD4+ T-cells at weeks 16 and 18 after randomisation. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, NCT02336074. FINDINGS: Between June 14, 2015 and Jul 11, 2017, 60 men with HIV were randomly assigned to receive either an ART-only (n=30) or an ART + V + V (n=30) regimen; all 60 participants completed the study, with no loss-to-follow-up. Mean total HIV DNA at weeks 16 and 18 after randomisation was 3·02 log10 copies HIV DNA per 106 CD4+ T-cells in the ART-only group versus 3·06 log10 copies HIV DNA per 106 CD4+ T-cells in ART + V + V group, with no statistically significant difference between the two groups (mean difference of 0·04 log10 copies HIV DNA per 106 CD4+ T-cells [95% CI -0·03 to 0·11; p=0·26]). There were no intervention-related serious adverse events. INTERPRETATION: This kick and kill approach conferred no significant benefit compared with ART alone on measures of the HIV reservoir. Although this does not disprove the efficacy kick and kill strategy, for future trials enhancement of both kick and kill agents will be required. FUNDING: Medical Research Council (MR/L00528X/1).

Kinetics of Early Innate Immune Activation during HIV-1 Infection of Humanized Mice.

Human immunodeficiency virus type 1 (HIV-1) infection is associated with aberrant immune activation; however, most model systems for HIV-1 have been used during established infection. Here, we utilize ultrasensitive HIV-1 quantification to delineate early events during the eclipse, burst, and chronic phases of HIV-1 infection in humanized mice. We show that very early in infection, HIV-1 suppresses peripheral type I interferon (IFN) and interferon-stimulated gene (ISG) responses, including the HIV-1 restriction factor IFI44. At the peak of innate immune activation, prior to CD4 T cell loss, HIV-1 infection differentially affects peripheral and lymphoid Toll-like receptor (TLR) expression profiles in T cells and macrophages. This results in a trend toward an altered activation of nuclear factor κB (NF-κB), TANK-binding kinase 1 (TBK1), and interferon regulatory factor 3 (IRF3). The subsequent type I and III IFN responses result in preferential induction of peripheral ISG responses. Following this initial innate immune activation, peripheral expression of the HIV-1 restriction factor SAM domain- and HD domain-containing protein 1 (SAMHD1) returns to levels below those observed in uninfected mice, suggesting that HIV-1 interferes with their basal expression. However, peripheral cells still retain their responsiveness to exogenous type I IFN, whereas splenic cells show a reduction in select ISGs in response to IFN. This demonstrates the highly dynamic nature of very early HIV-1 infection and suggests that blocks to the induction of HIV-1 restriction factors contribute to the establishment of viral persistence.IMPORTANCE Human immunodeficiency virus type 1 (HIV-1) infection is restricted to humans and some nonhuman primates (e.g., chimpanzee and gorilla). Alternative model systems based on simian immunodeficiency virus (SIV) infection of macaques are available but do not recapitulate all aspects of HIV-1 infection and disease. Humanized mice, which contain a human immune system, can be used to study HIV-1, but only limited information on early events and immune responses is available to date. Here, we describe very early immune responses to HIV-1 and demonstrate a suppression of cell-intrinsic innate immunity. Furthermore, we show that HIV-1 infection interacts differently with innate immune responses in blood and lymphoid organs.

Short-course antiretroviral therapy in primary HIV infection.

BACKGROUND: Short-course antiretroviral therapy (ART) in primary human immunodeficiency virus (HIV) infection may delay disease progression but has not been adequately evaluated. METHODS: We randomly assigned adults with primary HIV infection to ART for 48 weeks, ART for 12 weeks, or no ART (standard of care), with treatment initiated within 6 months after seroconversion. The primary end point was a CD4+ count of less than 350 cells per cubic millimeter or long-term ART initiation. RESULTS: A total of 366 participants (60% men) underwent randomization to 48-week ART (123 participants), 12-week ART (120), or standard care (123), with an average follow-up of 4.2 years. The primary end point was reached in 50% of the 48-week ART group, as compared with 61% in each of the 12-week ART and standard-care groups. The average hazard ratio was 0.63 (95% confidence interval [CI], 0.45 to 0.90; P=0.01) for 48-week ART as compared with standard care and was 0.93 (95% CI, 0.67 to 1.29; P=0.67) for 12-week ART as compared with standard care. The proportion of participants who had a CD4+ count of less than 350 cells per cubic millimeter was 28% in the 48-week ART group, 40% in the 12-week group, and 40% in the standard-care group. Corresponding values for long-term ART initiation were 22%, 21%, and 22%. The median time to the primary end point was 65 weeks (95% CI, 17 to 114) longer with 48-week ART than with standard care. Post hoc analysis identified a trend toward a greater interval between ART initiation and the primary end point the closer that ART was initiated to estimated seroconversion (P=0.09), and 48-week ART conferred a reduction in the HIV RNA level of 0.44 log(10) copies per milliliter (95% CI, 0.25 to 0.64) 36 weeks after the completion of short-course therapy. There were no significant between-group differences in the incidence of the acquired immunodeficiency syndrome, death, or serious adverse events. CONCLUSIONS: A 48-week course of ART in patients with primary HIV infection delayed disease progression, although not significantly longer than the duration of the treatment. There was no evidence of adverse effects of ART interruption on the clinical outcome. (Funded by the Wellcome Trust; SPARTAC Controlled-Trials.com number, ISRCTN76742797, and EudraCT number, 2004-000446-20.).

Rilpivirine exposure in plasma and sanctuary site compartments after switching from nevirapine-containing combined antiretroviral therapy.

OBJECTIVES: Pharmacokinetic parameters following modifications to antiretroviral therapy and sanctuary site exposure are often unknown for recently licensed antiretrovirals. We assessed plasma, CSF and seminal plasma (SP) exposure of rilpivirine after switching from nevirapine. METHODS: HIV-infected male subjects receiving tenofovir/emtricitabine/nevirapine (245/200/400 mg) once daily switched to tenofovir/emtricitabine/rilpivirine (245/200/25 mg) once daily for 60 days when CSF and semen samples were collected. Mean and individual plasma concentrations of nevirapine and rilpivirine were compared with the proposed plasma target concentration for nevirapine (3000 ng/mL) and the protein binding-adjusted EC90 for rilpivirine (12.1 ng/mL). Mean rilpivirine CSF and SP concentrations were calculated and individual values compared with the EC50 and EC90 for wild-type virus (0.27 and 0.66 ng/mL, respectively). RESULTS: Of 13 subjects completing study procedures including CSF examination, 8 provided seminal samples. By day 3, the mean plasma rilpivirine trough concentration was 29.7 ng/mL (95% CI: 23.8-37). No patient presented rilpivirine plasma concentrations under the proposed threshold. The mean rilpivirine concentration in CSF was 0.8 ng/mL (95% CI: 0.7-1.0), representing a CSF : plasma ratio of 1.4%, with concentrations above the EC90 in 85% (11/13) of patients. In SP, the mean rilpivirine concentration was 4.9 ng/mL (95% CI: 3.3-7.2), representing an SP : plasma ratio of 9.5%, with all concentrations above the EC90. CONCLUSIONS: Switching from nevirapine- to rilpivirine-containing antiretroviral therapy was safe and well tolerated, with plasma rilpivirine concentrations above the protein binding-adjusted EC90 in all subjects. Rilpivirine concentrations were always above the EC50 in the CSF and the EC90 in SP.

Restriction of V3 region sequence divergence in the HIV-1 envelope gene during antiretroviral treatment in a cohort of recent seroconverters.

BACKGROUND: Dynamic changes in Human Immunodeficiency Virus 1 (HIV-1) sequence diversity and divergence are associated with immune control during primary infection and progression to AIDS. Consensus sequencing or single genome amplification sequencing of the HIV-1 envelope (env) gene, in particular the variable (V) regions, is used as a marker for HIV-1 genome diversity, but population diversity is only minimally, or semi-quantitatively sampled using these methods. RESULTS: Here we use second generation deep sequencing to determine inter-and intra-patient sequence heterogeneity and to quantify minor variants in a cohort of individuals either receiving or not receiving antiretroviral treatment following seroconversion; the SPARTAC trial. We show, through a cross-sectional study of sequence diversity of the env V3 in 30 antiretroviral-naive patients during primary infection that considerable population structure diversity exists, with some individuals exhibiting highly constrained plasma virus diversity. Diversity was independent of clinical markers (viral load, time from seroconversion, CD4 cell count) of infection. Serial sampling over 60 weeks of non-treated individuals that define three initially different diversity profiles showed that complex patterns of continuing HIV-1 sequence diversification and divergence could be readily detected. Evidence for minor sequence turnover, emergence of new variants and re-emergence of archived variants could be inferred from this analysis. Analysis of viral divergence over the same time period in patients who received short (12 weeks, ART12) or long course antiretroviral therapy (48 weeks, ART48) and a non-treated control group revealed that ART48 successfully suppressed viral divergence while ART12 did not have a significant effect. CONCLUSIONS: Deep sequencing is a sensitive and reliable method for investigating the diversity of the env V3 as an important component of HIV-1 genome diversity. Detailed insights into the complex early intra-patient dynamics of env V3 diversity and divergence were explored in antiretroviral-naïve recent seroconverters. Long course antiretroviral therapy, initiated soon after seroconversion and administered for 48 weeks, restricts HIV-1 divergence significantly. The effect of ART12 and ART48 on clinical markers of HIV infection and progression is currently investigated in the SPARTAC trial.

Results of external quality assessment for proviral DNA testing of HIV tropism in the Maraviroc Switch collaborative study.

The Maraviroc Switch collaborative study (MARCH) is a study in aviremic patients on stable antiretroviral therapy and utilizes population-based sequencing of proviral DNA to determine HIV tropism and susceptibility to maraviroc. An external quality assessment (EQA) program was implemented to ensure competency in assessing the tropism of clinical samples conducted by MARCH laboratories (n = 14). The MARCH EQA has three prestudy phases assessing V3 loop sequencing and tropism determination using the bioinformatic algorithm geno2pheno, which generates a false-positive rate (FPR). DNA sequences with low FPRs are more likely to be from CXCR4-using (X4) viruses. Phase 1 of the EQA involved chromatogram interpretation. Phases 2, 2/3, and 3 involved patient and clonal samples. Clinical samples used in these phases were from treatment-experienced HIV-infected volunteers; 18/20 had viral loads of <50 copies/ml, and 10/15 were CXCR4-tropic on prior phenotyping. All samples were tested in triplicate, and any replicate with a geno2pheno FPR of <10% was designated X4. Performance was deemed adequate if ≤2 R5 and ≤1 X4 specimens were miscalled. For several clinical samples in the EQA, triplicate testing revealed marked DNA variability (FPR range, 0 to 96.7%). Therefore, a consensus-based approach was employed for each sample, i.e., a median FPR across laboratories was used to define sample tropism. Further sequencing analysis showed mixed viral populations in the clinical samples, explaining the differences in tropism predictions. All laboratories passed the EQA after achieving predefined competence thresholds in either of the phase 2 rounds. The use of clinical samples from patients resembling those who were likely to be screened in the MARCH, coupled with triplicate testing, revealed inherent DNA variability that might have been missed if single or duplicate testing and/or clonal samples alone were used. These data highlight the importance of intensive EQA of tropism laboratories before embarking on clinical studies. (This study has been registered at ClinicalTrials.gov under registration no. NCT01384682 [http://www.clinicaltrials.gov/ct2/show/study/NCT01384682?term=NCT01384682&rank=1].).

Characterization of Rare Spontaneous Human Immunodeficiency Virus Viral Controllers Attending a National United Kingdom Clinical Service Using a Combination of Serology and Molecular Diagnostic Assays.

Background: We report outcomes and novel characterization of a unique cohort of 42 individuals with persistently indeterminate human immunodeficiency virus (HIV) status, the majority of whom are HIV viral controllers. Methods: Eligible individuals had indeterminate or positive HIV serology, but persistently undetectable HIV ribonucleic acid (RNA) by commercial assays and were not taking antiretroviral therapy (ART). Routine investigations included HIV Western blot, HIV viral load, qualitative HIV-1 deoxyribonucleic acid (DNA), coinfection screen, and T-cell quantification. Research assays included T-cell activation, ART measurement, single-copy assays detecting HIV-1 RNA and DNA, and plasma cytokine quantification. Human immunodeficiency virus seropositivity was defined as ≥3 bands on Western blot; molecular positivity was defined as detection of HIV RNA or DNA. Results: Human immunodeficiency virus infection was excluded in 10 of 42 referrals, remained unconfirmed in 2 of 42, and was confirmed in 30 of 42, who were identified as HIV elite controllers (ECs), normal CD4 T-cell counts (median 820/mL, range 805-1336), and normal CD4/CD8 ratio (median 1.8, range 1.2-1.9). Elite controllers had a median duration of elite control of 6 years (interquartile range = 4-14). Antiretroviral therapy was undetected in all 23 subjects tested. Two distinct categories of ECs were identified: molecular positive (n = 20) and molecular negative (n = 10). Conclusions: Human immunodeficiency virus status was resolved for 95% of referrals with the majority diagnosed as EC. The clinical significance of the 2 molecular categories among ECs requires further investigation.

CNS effects of a CCR5 inhibitor in HIV-infected subjects: a pharmacokinetic and cerebral metabolite study.

BACKGROUND: We conducted a pharmacokinetic and in vivo cerebral (1)H magnetic resonance spectroscopy ((1)H-MRS) study to assess CSF exposure and cerebral metabolite ratios (CMRs) following maraviroc intensification. METHODS: HIV-infected neurologically asymptomatic adults receiving tenofovir, emtricitabine and lopinavir/ritonavir with plasma HIV RNA <50 copies/mL were eligible and received intensified therapy with 150 mg of maraviroc twice daily. (1)H-MRS was performed in several cerebral locations, including the right basal ganglia (RBG), to assess CMRs, including N-acetyl aspartate/creatine (NAA/Cr), at baseline and after 14 days. Subsequently, on day 15, blood samples were obtained to determine plasma concentrations of maraviroc pre-dose (C(trough)) and then paired blood and CSF samples were collected at 4 or 6 h post-dose. Associations between maraviroc exposure, clinical parameters and changes to CMRs were evaluated. TRIAL REGISTRY: ClinicalTrials.gov (http://clinicaltrials.gov/ct2/show/NCT00982878). RESULTS: Twelve subjects (75% male) participated with a mean (SD) CD4+ cell count of 503 (199) cells/µL. Mean (SD) maraviroc plasma concentrations at pre-dose, 4 h post-dose and 6 h post-dose were 337 (74), 842 (174) and 485 (100) ng/mL and CSF concentrations at 4 h post-dose and 6 h post-dose were 7.5 (1.3) and 5.1 (1.2) ng/mL. The mean maraviroc CSF : plasma ratio (range) was 1.01% (0.57%-1.61%). An increase of 14.8% was observed for the RBG NAA/Cr ratio, which was significantly associated with higher maraviroc plasma C(trough) (P = 0.05, r = 0.61), but not CSF concentration (P = 0.16, r = 0.46). CONCLUSIONS: After 14 days of maraviroc intensification, small increases in cerebral metabolite markers of neuronal integrity (NAA/Cr ratios) were observed and are associated with maraviroc plasma C(trough).

Alterations in cerebrospinal fluid chemokines are associated with maraviroc exposure and in vivo metabolites measurable by magnetic resonance spectroscopy.

BACKGROUND: Cerebrospinal (CSF) fluid biomarkers may be a useful tool for assessing the cerebral effects of antiretroviral therapy. OBJECTIVE: The aim of the study was to investigate the relationship between 4 CSF chemokines with maraviroc exposure and cerebral metabolite ratios (CMR) measured by magnetic resonance spectroscopy (1H-MRS) in HIV-infected individuals following maraviroc intensification. METHODS: CSF concentration of maraviroc and 4 chemokines (MCP-1, IP-10, MCP-4, and MIP-1ß), plasma concentration of maraviroc pre-CSF assessment, and right basal ganglia CMR were assessed in 12 male HIV-infected, neuro-asymptomatic adults after 14 days of antiretroviral therapy intensification with maraviroc 150 mg twice daily. The relationship between CSF analytes with both CMRs and plasma and CSF maraviroc concentrations were examined using Spearman correlation coefficient. RESULTS: Twelve subjects completed study procedures with baseline values as follows: mean (SD) age 42 (8) years, CD4+ cell count 503 (199) cells/µL, and plasma HIV RNA<50 copies/mL in most subjects. Mean (range, pg/mL) chemokine concentrations were IP-10, 1242 (190-8073); MCP-4, 6.52 (1-18); MCP-1, 702 (201-1618); and MIP-1ß, 42 (5-153). IP-10, MCP-4, and MIP-1ß were significantly associated with CMRs in the right basal ganglia with (1) lower concentrations of IP-10 correlating with higher N-acetyl aspartate to creatine ratios (NAA/Cr) and (2) higher concentrations of MCP-4 and MIP-1ß correlating with higher myoinositol to creatine (mI/Cr) ratios. There were no significant associations with MCP-1. Finally lower concentrations of IP-10 were significantly associated with higher maraviroc plasma trough concentration (r=-0.629, P=.028) but not CSF concentration (r=-0.308, P=.331). CONCLUSION: We hypothesize that the relationship between IP-10, MCP-4, and MIP-1ß with maraviroc exposure and CMRs may be associated with a direct cerebral effect of maraviroc.

Development of a sensitive, quantitative assay with broad subtype specificity for detection of total HIV-1 nucleic acids in plasma and PBMC.

An LTR-based quantitative PCR (qPCR) assay was modified and optimized for the quantification of total HIV-1 nucleic acids in plasma and PBMC. TaqMan qPCR primers and probes were designed against the NCBI/LANL HIV-1 compendium database by analyzing sequences used in assays for sensitive cross-clade detection of HIV-1 as reported in the literature and elucidating regions of improved cross-subtype specificity. Inosine and mixed nucleotide bases were included at polymorphic sites. Real-time RT-qPCR and qPCR were performed on plasma viral RNA and cellular lysates. A step-up amplification approach to allow binding of primers across polymorphic regions showed improved sensitivity compared to universal cycling. Unlike a lead competing laboratory-developed assay, all major HIV-1 subtypes, and a wide range of recombinants from a 127-member diversity panel were detected and accurately quantified in spiked plasmas. Semi-nested PCR increased detection sensitivity even further. The assay was able to detect down to 88 copies/mL of HIV-1 in plasma with 95% efficiency or the equivalent of a single infected cell. The PCR assay will be valuable in studies that monitor very low viral levels including residual or break through HIV-1 in patients receiving antiretroviral therapy, in HIV-1 cure, and in other research studies.

Antiretroviral drug resistance in HIV-1-infected patients with low-level viremia.

This study characterized the prevalence and patterns of antiretroviral-drug-resistance mutations according to plasma human immunodeficiency virus type 1 (HIV-1) RNA load in a large population of patients with HIV-1 infection who underwent testing for resistance mutations in routine clinical practice. HIV-1 genotypic resistance test results with linked clinical data were obtained from national resistance and clinical databases in the United Kingdom. Among 7861 tests, detection of > or =1 resistance mutation was most frequent at viral loads of 300-10,000 copies/mL and decreased statistically significantly at viral loads of >10,000 copies/mL. Major resistance mutations were commonly detected in the subset of tests that were performed among patients with viral loads of <1000 copies/mL (1001 [12.7%] of 7861 tests). We conclude that HIV-1 genotypic resistance testing is informative for patients with low viral loads.

Mouse DNA contamination in human tissue tested for XMRV.

BACKGROUND: We used a PCR-based approach to study the prevalence of genetic sequences related to a gammaretrovirus, xenotropic murine leukemia virus-related virus, XMRV, in human prostate cancer. This virus has been identified in the US in prostate cancer patients and in those with chronic fatigue syndrome. However, with the exception of two patients in Germany, XMRV has not been identified in prostate cancer tissue in Europe. Most putative associations of new or old human retroviruses with diseases have turned out to be due to contamination. We have looked for XMRV sequences in DNA extracted from formalin-fixed paraffin- embedded prostate tissues. To control for contamination, PCR assays to detect either mouse mitochondrial DNA (mtDNA) or intracisternal A particle (IAP) long terminal repeat DNA were run on all samples, owing to their very high copy number in mouse cells. RESULTS: In general agreement with the US prevalence, XMRV-like sequences were found in 4.8% of prostate cancers. However, these were also positive, as were 21.5% of XMRV-negative cases, for IAP sequences, and many, but not all were positive for mtDNA sequences. CONCLUSIONS: These results show that contamination with mouse DNA is widespread and detectable by the highly sensitive IAP assay, but not always with less sensitive assays, such as murine mtDNA PCR. This study highlights the ubiquitous presence of mouse DNA in laboratory specimens and offers a means of rigorous validation for future studies of murine retroviruses in human disease.

Undetectable plasma viral load predicts normal survival in HIV-2-infected people in a West African village.

BACKGROUND: There have been no previous studies of the long-term survival and temporal changes in plasma viral load among HIV-2 infected subjects. METHODS: 133 HIV-2 infected and 158 HIV-uninfected subjects from a rural area in North-west Guinea-Bissau, West Africa were enrolled into a prospective cohort study in 1991 and followed-up to mid-2009. Data were collected on four occasions during that period on HIV antibodies, CD4% and HIV-2 plasma viral load. RESULTS: Median age (interquartile range [IQR]) of HIV-2 infected subjects at time of enrollment was 47 (36, 60) years, similar to that of HIV-uninfected control subjects, 49 (38, 62) (p = 0.4). Median (IQR) plasma viral load and CD4 percentage were 347 (50, 4,300) copies/ml and 29 (22, 35) respectively.Overall loss to follow-up to assess vital status was small, at 6.7% and 6.3% for HIV-2 infected and uninfected subjects respectively. An additional 17 (12.8%) and 16 (10.1%) of HIV-2 infected and uninfected subjects respectively were censored during follow-up due to infection with HIV-1. The mortality rate per 100 person-years (95% CI) was 4.5 (3.6, 5.8) among HIV-2 infected subjects compared to 2.1 (1.6, 2.9) among HIV-uninfected (age-sex adjusted rate ratio 1.9 (1.3, 2.8, p < 0.001) representing a 2-fold excess mortality rate associated with HIV-2 infection.Viral load measurements were available for 98%, 78%, 77% and 61% HIV-2 infected subjects who were alive and had not become super-infected with HIV-1, in 1991, 1996, 2003 and 2006 respectively. Median plasma viral load (RNA copies per ml) (IQR) did not change significantly over time, being 150 (50, 1,554; n = 77) in 1996, 203 (50, 2,837; n = 47) in 2003 and 171 (50, 497; n = 31) in 2006. Thirty seven percent of HIV-2 subjects had undetectable viraemia (<100 copies/ml) at baseline: strikingly, mortality in this group was similar to that of the general population. CONCLUSIONS: A substantial proportion of HIV-2 infected subjects in this cohort have stable plasma viral load, and those with an undetectable viral load (37%) at study entry had a normal survival rate. However, the sequential laboratory findings need to be interpreted with caution given the number of individuals who could not be re-examined.

Characterization of low level viraemia in HIV-infected patients receiving boosted protease inhibitor-based antiretroviral regimens.

To understand the pathogenesis of low level viraemia (LLV) in HIV-infected patients on boosted protease inhibitors (PI/b), we enrolled 34 subjects with a median HIV-RNA 79 copies/mL and followed them for 15 months. Samples for next generation sequencing were collected at three time-points. Two showed resistance-associated mutations (RAMs) in the protease gene, while 95-100% had RAMs in the gag gene, which evolved in approximately a quarter of subjects, suggesting a potential clinical role of these kind of mutations.

Genotypic analysis of two hypervariable human cytomegalovirus genes.

Most human cytomegalovirus (HCMV) genes are highly conserved in sequence among strains, but some exhibit a substantial degree of variation. Two of these genes are UL146, which encodes a CXC chemokine, and UL139, which is predicted to encode a membrane glycoprotein. The sequences of these genes were determined from a collection of 184 HCMV samples obtained from Africa, Australia, Asia, Europe, and North America. UL146 is hypervariable throughout, whereas variation in UL139 is concentrated in a sequence encoding a potentially highly glycosylated region. The UL146 sequences fell into 14 genotypes, as did all previously reported sequences. The UL139 sequences grouped into 8 genotypes, and all previously reported sequences fell into a subset of these. There were minor differences among continents in genotypic frequencies for UL146 and UL139, but no clear geographical separation, and identical nucleotide sequences were represented among communities distant from each other. The frequent detection of multiple genotypes indicated that mixed infections are common. For both genes, the degree of divergence was sufficient to preclude reliable sequence alignments between genotypes in the most variable regions, and the mode of evolution involved in generating the genotypes could not be discerned. Within genotypes, constraint appears to have been the predominant mode, and positive selection was detected marginally at best. No evidence was found for linkage disequilibrium. The emerging scenario is that the HCMV genotypes developed in early human populations (or even earlier), becoming established via founder or bottleneck effects, and have spread, recombined and mixed worldwide in more recent times.

Changes in viral load and HBsAg and HBeAg status with age in HBV chronic carriers in The Gambia.

BACKGROUND: Little is known about changes in hepatitis B viral load (HBV DNA) in relation to age in Africa. The aim of this study is to determine the natural course of HBV chronic infection, particularly in relation to sequential changes in serum HBV DNA levels and hepatitis B surface (HBsAg) antigen/hepatitis e antigen (HBeAg) status by age. METHODS: The study was conducted on 190 HBV chronic carriers, aged 1-19 years who were followed for 19 years. 160, 99 and 123 were traced at 5, 9 and 19 years later. All available samples were tested for HBsAg and HBeAg, whilst 170, 61, 63 and 81 were tested for HBV DNA at the baseline, and at 5, 9 and 19 years following recruitment. RESULTS: In general HBeAg which correlated with high levels of HBV DNA was lost at a much faster rate than HBsAg. 86% of the carriers who were recruited at the age of 1-4 yrs lost HBeAg by the age of 19 years compared to 30% who lost HBsAg. HBeAg negative carriers had serum HBV DNA levels of < 105 copies per mL, HBV DNA positivity declined from 100% in 1-4 yrs old carriers at recruitment to 62.5%,60% and 88% at 5, 9 and 19 years respectively following recruitment. CONCLUSION: After 19 years of follow up, the majority of HBV surface antigen carriers had lost HBeAg positivity and had low levels of viral replication. However small proportions (10-20%) retained HBeAg and continue to have high levels of viral replication.

Use of next-generation sequencing in the CHAT study (acute HCV in HIV): effect of baseline resistance-associated NS3 variants on treatment failure.

Background The epidemic of acute HCV infection among HIV-infected men who have sex with men (MSM) is ongoing. Transmission of drug-resistant variants (DRVs) after HCV treatment failure could pose a major threat to the effectiveness of future therapies. We determined the baseline prevalence of pre-existing DRVs in the HCV NS3 protease gene and their effects on the addition of telaprevir (TVR) to standard pegylated interferon and ribavirin (PEG-IFN/RBV) for acute HCV infection in individuals enrolled in a multicentre randomized controlled trial (2013 and 2014). Methods The HCV NS3 viral protease was analyzed using Sanger and next-generation sequencing (NGS) for DRVs at baseline (n = 31), and at viral breakthrough following TVR-based treatment (n = 3) or PEG-IFN/RBV alone (n = 2). Results Sequence analysis indicated that all individuals were infected with HCV genotype 1a. Complete (100%) concordance was seen between Sanger and NGS for high levels of mutant viral populations. The simeprevir-associated Q80K variant was present at high frequency in the German samples (7/11-64%) and infrequently in the UK samples (1/20-5%). In the three TVR-based treatment failures, V36M/l and R155K/T emerged, but not R155G which was detectable at low levels in two individuals at baseline. Failure rate at week 24 was 26.7% (with baseline DRVs) vs. 6.3% (without baseline DRVs), p = 0.17). Comparison of sequences pre- and post-therapy in 5 who failed therapy revealed the emergence of not previously described variants V193G, E176K, P189S (on TVR), and V181S in one instance each. Conclusion The presence of baseline DRVs for the NS3 protease gene of HCV genotype 1a did not appear to predict treatment failure in our patient cohort. Where detected, Q80K was present at high levels (>98%), but had no effect on outcomes and remained high after failure.

Prevalence of primary genotypic resistance in a UK centre: Comparison of primary HIV-1 and newly diagnosed treatment-naive individuals.

The worrying finding that up to 19% of newly diagnosed HIV-1 cases in the UK have genotypic evidence of transmitted drug-resistant HIV-1 (TrDR-HIV-1) does not concur with levels observed in one London centre. A study of the prevalence of resistance in primary HIV infection and newly diagnosed antiretroviral-naive individuals demonstrated significantly lower levels of TrDR-HIV-1 than previously reported. Variations in the prevalence of TrDR-HIV-1 may reflect the heterogeneity of methodologies and definitions used for resistance.