HIV-negative Volunteers Research Articles

Inflammasome activation in patients with Kaposi sarcoma herpesvirus–associated diseases

AbstractKaposi sarcoma herpesvirus (KSHV)–associated diseases include Kaposi sarcoma (KS), primary effusion lymphoma (PEL), KSHV-associated multicentric Castleman disease (MCD), and KS inflammatory cytokine syndrome (KICS). PEL, MCD, and KICS are associated with elevated circulating inflammatory cytokines. However, activation of the inflammasome, which generates interleukin-1β (IL-1β) and IL-18 via active caspase-1/4/5, has not been evaluated in patients with KSHV-associated diseases (KADs). Herein we report that patients with HIV and ≥1 KAD present with higher plasma levels of IL-18 and increased caspase-1/4/5 activity in circulating monocytes compared with HIV-negative healthy volunteers (HVs) or people with HIV (PWH) without KAD. Within KAD subtypes, KICS and MCD shared enhanced caspase-1/4/5 activity and IL-18 production compared with HVs and PWH, whereas patients with PEL showed remarkably high levels of inflammasome complex formation (known as apoptosis–associated speck-like protein containing a caspase recruitment domain). Moreover, caspase-1/4/5 activity and IL-18 plasma levels correlated with KSHV viral load, indicating KSHV-driven inflammasome activation in KAD. Accordingly, factors released by cells latently infected with KSHV triggered inflammasome activation and cytokine production in bystander monocytes in vitro. Finally, both supervised and unsupervised analyses with inflammasome measurements and other inflammatory biomarkers demonstrate a unique inflammatory profile in patients with PEL, MCD, and KICS as compared with KS. Our data indicate that detrimental inflammation in patients with KAD is at least partially driven by KSHV-induced inflammasome activation in monocytes, thus offering novel approaches to diagnose and treat these complex disorders. These trials were registered at www.ClinicalTrials.gov as #NCT01419561, NCT00092222, NCT00006518, and NCT02147405.

The frequency of class G immunoglobulins` formation to the SARS-CoV-2 coronavirus in immunization of HIV-infected patients with Gam-COVID-Vac vaccine and the reactogenicity of the vaccine

The research aimed to study the frequency of class G antibodies` formation to SARS-CoV-2 in HIV-infected patients in response to immunization with the Gam-COVID-Vac vaccine and the reactogenicity of the vaccine.Materials and methods. 36 HIV-infected and 38 HIV-negative volunteers were vaccinated. The inclusion criteria for patients were: age 18 years and older; absence of earlier disease COVID-19; negative test of the presence of RNA in a smear from the nasopharyngeal and oropharyngeal mucosa and IgG in blood serum to SARS-CoV-2, absence of contraindications, undetectable viral load. The number of CD4+ lymphocytes in the blood of HIV-infected people before vaccination was 520,0±9,6. It was used the two-dose vaccine Gam-COVID-Vac, developed by National Research Center named after N.F. Gamaliel. The interval between the administration of the vaccine was 24,2±0,5 days. The presence of IgG before vaccination and 44–54±0,6 days after the start of vaccination to SARS-CoV-2 coronavirus was determined by enzyme immunoassay using the SARS-CoV-2-RBD-ELISA-Gamaleya test system. The positivity index (PI) was calculated for each test sample. The sample was considered positive at IP>1.Results. The presence of antibodies in HIV-infected patients was detected in 75,0% cases, in HIV-negative — in 92,1% cases, the arithmetic average of the positivity index was 10,3±1,9 in the observation group, 15,3±1,9 in the comparison group (c2=3,9; p=0,04). There are no postvaccinal complications registered in patients of both groups. The frequency of general reactions to the introduction of the first and (or) second components of the vaccine in the group of HIV-infected and HIV-negative did not differ and amounted to 8,3 and 13,2%, respectively. Local reactions among HIV-infected (in 19,4% of cases) were less common than among HIV-negative (in 47,4% of cases) (c2=6,4; p=0,01).Conclusion. Humoral immunity in response to immunization of Gam-COVID-Vac against SARS-CoV-2 in HIV-infected with minor immunosuppression is less pronounced than in HIV-negative. However, the production of postvaccinal class G immunoglobulins in HIV-infected patients in 75,0% of cases and the weak reactogenicity of the vaccine it is recommended for using in people living with HIV on the back of effective antiretroviral therapy.

Analysis of HPV Vaccination Willingness amongst HIV-Negative Men Who Have Sex with Men in China.

Objective: Men who have sex with men (MSM) are high-risk groups of human papillomavirus (HPV) infection, the best measure to prevent this is the HPV vaccine. However, few studies have investigated HPV vaccination willingness in the MSM population in China. We aimed to explore the willingness of human immunodeficiency virus (HIV)-negative MSM for HPV vaccination and the factors affecting their willingness to vaccinate. Methods: We adopted a non-probability sampling method to recruit HIV-negative MSM volunteers. Participants completed a questionnaire, including sociodemographic characteristics, sexual behavior characteristics, HPV infection and vaccine-related knowledge, risk perception, and HPV vaccination willingness and promotion attitudes. Results: Of the 406 HIV-negative MSM surveyed, 86.21% were willing to receive HPV vaccine. HPV infection and vaccine-related knowledge (odds ratio [OR] = 2.167, 95% confidence interval [CI] = 1.049–4.474), HPV infection risk perception (OR = 5.905, 95% CI = 1.312–26.580), and HPV vaccine promotion attitude (OR = 6.784, 95% CI = 3.164–14.546) were all related to HPV vaccination willingness. Conclusion: MSM have a high willingness for HPV vaccination. Strengthening health education for MSM, raising their awareness of HPV infection and vaccines, and promoting their risk perception of HPV infection will help increase their willingness for HPV vaccination.

MOSQUITO-BORNE PARASITES IN PATIENTS NEWLY INFECTED WITH HIV IN RELATIONSHIP WITH CD4 COUNT AND TNF ΑLPHA

Background: Mosquito-borne parasites include the pathogenic protozoa and helminths that are transmitted by the insect vector which may co-infect with other organisms to elicit an immune response. Purpose: To determine the frequency of mosquito-borne parasites in patients newly infected with HIV in relationship with CD4 count and TNFα. Method: Thirty-one (31; aged 15-32 years; male-12; female-19) newly diagnosed HIV positive patients and fifty (50) age-matched HIV negative volunteers were recruited as a control subject for this study. All subjects were negative to anti-HCV/HBsAg ELISA, Plasmodium, Acid-Fast Bacilli (AFB) tests and the control subjects were also negative to HIVP24 Ag-Ab ELISA, Plasmodium spp. and Wuchereria bancrofti microscopy. Venous blood including Night blood samples and sputum samples were obtained from the participants for CD4 count by cyflowmetry, TNFα, HIVP24Ag-Ab, anti-HCV, HBsAg by ELISA and microscopic identification by Giemsa staining while Sputum sample was used for Ziehl Neelsen staining to demonstrate Acid Fast Bacilli (AFB). Result: A lower frequency of 25.8% (Rajan, 2008) Plasmodium spp. and 6.5% (James et al., 2015) W. bancrofti was obtained in newly infected HIV patients compared with 32% (Zeitlmann et al., 2001) Plasmodium spp. and 8% (WHO, 2019) W. bancrofti obtained in the non-HIV infected control subjects. Showed a significant decrease in CD4 count and increase in plasma TNFα in both HIV mono-infection and coinfection with Plasmodium spp. and W. bancrofti compared with the results obtained in the non-HIV infected control subjects (p<0.05) and the results obtained in the newly infected HIV patients without Plasmodium spp. and W. coinfection (p<0.05). Conclusion: There was a significant increase in plasma TNFα and a decrease in CD4 count in both HIV mono-infection and coinfection with Plasmodium spp. and W. bancrofti while a lower frequency of Plasmodium spp. and W. bancrofti was obtained in newly infected HIV patients compared with the results obtained in the non-HIV infected control subjects.

Antimalarial drug resistance markers in human immunodeficiency virus (HIV)-positive and HIV-negative adults with asymptomatic malaria infections in Port Harcourt, Nigeria.

In Nigeria, indiscriminate use of antimalarial drugs may contribute to the threat of drug resistance, but this has not been evaluated among people living with human immunodeficiency virus (HIV). HIV-positive adults attending a university hospital HIV clinic and HIV-negative adult volunteers from the university hospital community with a positive blood film were treated with artemether-lumefantrine. Parasite DNA from before and after treatment was polymerase chain reaction amplified to identify molecular markers of drug susceptibility. The pfcrt76T genotype was prevalent among both HIV-positive and HIV-negative participants (78.6% and 68.2%, respectively). Three new mutations in the pfmdr1 gene-F73S, S97L and G165R-and the uncommon pfdhps S436F variant were detected, whereas pfdhps K540E and pfdhfr I164L were absent. The A437G allele of pfdhps predominated (62/66 [94%]). The I431 V mutation was found in 19 of 66 pretreatment pfdhps sequences (28.8%). The pfmdr1 86N allele was significantly more common at day 3 post-treatment than at baseline (odds ratio 8.77 [95% confidence interval 1.21 to 380]). We found evidence of continued chloroquine use among HIV-positive individuals. Selection for the pfmdr1 86N after artemether-lumefantrine treatment was observed, indicating a possible threat to antimalarial efficacy in the study area. The complexity of pfdhps haplotypes emphasises the need for careful monitoring of anti-folate susceptibility in Nigeria.

Persistent TCell Repertoire Perturbation and TCell Activation in HIV After Long Term Treatment.

ObjectiveIn people living with HIV (PLHIV), we sought to test the hypothesis that long term anti-retroviral therapy restores the normal T cell repertoire, and investigate the functional relationship of residual repertoire abnormalities to persistent immune system dysregulation.MethodsWe conducted a case-control study in PLHIV and HIV-negative volunteers, of circulating T cell receptor repertoires and whole blood transcriptomes by RNA sequencing, complemented by metadata from routinely collected health care records.ResultsT cell receptor sequencing revealed persistent abnormalities in the clonal T cell repertoire of PLHIV, characterized by reduced repertoire diversity and oligoclonal T cell expansion correlated with elevated CD8 T cell counts. We found no evidence that these expansions were driven by cytomegalovirus or another common antigen. Increased frequency of long CDR3 sequences and reduced frequency of public sequences among the expanded clones implicated abnormal thymic selection as a contributing factor. These abnormalities in the repertoire correlated with systems level evidence of persistent T cell activation in genome-wide blood transcriptomes.ConclusionsThe diversity of T cell receptor repertoires in PLHIV on long term anti-retroviral therapy remains significantly depleted, and skewed by idiosyncratic clones, partly attributable to altered thymic output and associated with T cell mediated chronic immune activation. Further investigation of thymic function and the antigenic drivers of T cell clonal selection in PLHIV are critical to efforts to fully re-establish normal immune function.

Feasibility of establishing an HIV vaccine preparedness cohort in a population of the Uganda Police Force: Lessons learnt from a prospective study.

BackgroundMembers of uniformed armed forces are considered to be at high risk for HIV infection and have been proposed as suitable candidates for participation in HIV intervention studies. We report on the feasibility of recruitment and follow up of individuals from the community of the Uganda Police Force (UPF) for an HIV vaccine preparedness study.MethodsHIV-negative volunteers aged 18–49 years, were identified from UPF facilities situated in Kampala and Wakiso districts through community HIV counselling and testing. Potential volunteers were referred to the study clinic for screening, enrolment and quarterly visits for one year. HIV incidence, retention rates were estimated and expressed as cases per 100 person years of observation (PYO). Rate ratios were used to determine factors associated with retention using Poisson regression models.ResultsWe screened 560 to enroll 500 volunteers between November 2015 and May 2016. One HIV seroconversion occurred among 431 PYO, for an incidence rate of 0.23/100 PYO (95% confidence interval [CI]: 0.03–1.64). Overall, retention rate was 87% at one year, and this was independently associated with residence duration (compared to <1 year, 1 to 5 years adjusted rate ratio (aRR) = 1.19, 95%CI: 1.00–1.44); and >5 years aRR = 1.34, 95%CI: 0.95–1.37); absence of genital discharge in the last 3 months (aRR = 1.97, 95% CI: 1.38–2.83, absence of genital ulcers (aRR = 1.90, 95%CI: 1.26–2.87, reporting of new sexual partner in the last month (aRR = 0.57, 95%CI: 0.45–0.71, being away from home for more than two nights (aRR = 1.27, 95%CI: 1.04–1.56, compared to those who had not travelled) and absence of knowledge on HIV prevention (aRR = 2.67, 95%CI: 1.62–4.39).ConclusionsWhile our study demonstrates the feasibility of recruiting and retaining individuals from the UPF for HIV research, we did observe lower than anticipated HIV incidence, perhaps because individuals at lower risk of HIV infection may have been the first to come forward to participate or participants followed HIV risk reduction measures. Our findings suggest lessons for recruitment of populations at high risk of HIV infection.

Comparison of Safety and Vector-Specific Immune Responses in Healthy and HIV-Infected Populations Vaccinated with MVA-B.

There are few studies comparing the safety and immunogenicity of the same HIV immunogen in healthy volunteers and HIV-infected individuals. We analyzed demographics, adverse events (AEs), and immunogenicity against vaccinia virus in preventive (RISVAC02, n = 24 low-risk HIV-negative volunteers) and therapeutic (RISVAC03, n = 20 successfully treated chronically HIV-1-infected individuals) vaccine phase-I clinical trials that were performed with the same design and the same immunogen (modified vaccinia virus Ankara-B: MVA-B). Total AEs were significantly higher in HIV-infected patients (mean AEs/patient 6.6 vs. 12.8 (p < 0.01)). Conversely, the number of AEs related to vaccination (AEsRV) was similar between both groups. No grade III or IV AEsRV were observed in either clinical trial. Regarding the immunogenicity, the proportion of anti-vaccinia virus antibody responders was similar in both studies. Conversely, the magnitude of response was significantly higher in HIV-infected patients (median binding antibodies at w8 267 vs. 1600 U/mL (p = 0.002) and at w18 666 vs. 3200 U/mL (p = 0.003)). There was also a trend towards higher anti-vaccinia virus neutralizing activity in HIV-infected individuals (proportion of responders 37% vs. 63% (p = 0.09); median IC50 32 vs. 64 (p = 0.054)). This study confirms the safety of MVA-B independent of HIV serostatus. HIV-infected patients showed higher immune responses against vaccinia virus.

Assessing pharmacokinetic marker correlates of outcome, with application to antibody prevention efficacy trials.

The Antibody Mediated Prevention efficacy trials are the first studies to evaluate whether passive administration of a broadly neutralizing monoclonal antibody can prevent human immunodeficiency virus (HIV) acquisition. The trials randomize 4600 HIV-negative volunteers to receive 10 infusions of the monoclonal antibody VRC01 or placebo. The primary objective compares the incidence of HIV infection between the study groups. The secondary objective assesses whether and how a marker defined as the serum concentration of VRC01 over time associates with the instantaneous rate of HIV infection, using a two-phase sampling design, a pharmacokinetic model for the time-concentration curve, and an estimator of HIV infection times. While a Cox model with a time-dependent covariate constitutes an important approach to this problem, the low interindividual versus intraindividual marker variability limits its power, motivating us to develop two alternative methods that condition on outcome status: (1) an indirect method that checks whether HIV-infected cases have unexpectedly long times from the most recent infusion to the estimated infection date and (2) a direct method that checks whether the marker itself is unexpectedly low at estimated infection dates. In simulations and a pseudo Antibody Mediated Prevention application, we find that method (2) (but not (1)) has greater power than the Cox model. We also find that the quality of the infection time estimator majorly impacts method performance, and thus, incorporating details of an optimized estimator is critical. The methods apply more generally for assessing a time-dependent longitudinal marker as a correlate of risk when the marker trajectory is modeled pharmacokinetically.

The in vitro Mycobacterium bovis\xa0BCG Moreau infection of human monocytes that induces Caspase-1 expression, release and dependent cell death is mostly reliant upon cell integrity

BackgroundCaused by Mycobacterium tuberculosis, tuberculosis (TB) is an extremely contagious disease predominantly affecting the lungs. TB is found worldwide and has a major impact on public health safety primarily due to its high mortality rate. Applied for over a hundred years as a preventive measure, Mycobacterium bovis BCG remains the only available TB vaccine. Only one seminal study about the apoptotic pathways induced by this vaccine in the monocytic lineage of the host cell has found the effects of BCG on regulation of apoptosis. The aim of this study was to explore beyond that pioneer study the pathway related to the in vitro cell-death pattern and the inflammatory response to the BCG vaccine in human monocytes.MethodsCohorts of HIV-negative volunteers were enrolled: adult Healthy Donors (HD) and neonates’ Umbilical Cord Blood (UCB) individuals. Host mononuclear cells were infected with the M. bovis Moreau strain of BCG vaccine at 16, 24, 48, and 72 h. The Real-Time RT-PCR for TRADD, Bcl-2, and Caspases-1 and -3 were performed, and supernatants were assayed in parallel for Caspase-1, NLRP3, HO-1, and IL-1β levels whereas caspases were assessed intracellularly. The effect of a BCG infection in monocytes was characterized via a metabolic activity assay by LDH release profiles.ResultsOverall, the BCG vaccine induced significantly higher Caspase-1 and Bcl-2 mRNA levels in both the HD and UCB groups (p-value ≤0.05). In addition, a significant increase solely in Caspase-1 protein levels was also noted in both HD and UCB (p-value ≤0.05) notwithstanding the absence of any damaged cell membranes.ConclusionsOur data directly corroborate other findings showing that BCG Moreau led to an increased secretion of IL-1β but not IL-18, two Caspase-1-activated cytokines, and are also in support of the model that the BCG Moreau infection of human mononuclear cells may induce a cell-death pattern involving Caspase-1 activation.

OC 8491 PREPVACC: A PHASE III, MAMS ADAPTIVE PROPHYLACTIC HIV VACCINE TRIAL WITH A SECOND RANDOMISATION TO COMPARE F/TAF WITH TDF/FTC PREP

BackgroundThere remains an urgent need for a prophylactic HIV vaccine to control generalised epidemics. PrEP has demonstrated effectiveness of 86% and is recommended by WHO; uptake is generally high, but retention is disappointing in some settings. The EDCTP2 project PrEPVacc will assess the efficacy of two combination prophylactic vaccine regimens (DNA, MVA and Env protein/adjuvant) each compared to placebo and the proportion of infections averted by F/TAF in comparison to TDF/FTC. A Registration Cohort, recruiting HIV negative volunteers at risk of HIV will precede the trial.MethodsThe PrEPVacc partnership agreed that 70% vaccine efficacy had public health relevance. The trial usesnstagesoftware for multi-arm, multi-stage designs (MAMS) and the averted infections ratio (AIR) methodology with participants randomised (i) 1:1:1 to active product or placebo (ii) 1:1 to TDF/FTC : F/TAF until week 26 (presumed peak immunogenicity). Access to PrEP in the Registration Cohort and after week 26 will be standard of care. HIV seroconversions occurring between weeks 0–26 will inform the PrEP analysis, incorporating HIV incidence amongst those who do not take up PrEP locally in the Registration Cohort. Seroconversions after week 26 will inform vaccine analyses.ResultsUp to 556 participants per group affords 92% power to detect vaccine efficacy of 70% at the final analysis, assuming incidence of 4/100-person years and 10% loss with 81% and 97% power to conclude that F/TAF can avert half or more of the infections prevented by TDF/FTC if effectiveness of TDF/FTC is 70% and 80%, respectively.ConclusionPrEPVacc adopts a pragmatic approach to uncertainties around HIV incidence in settings where PrEP is increasingly available. This innovative adaptive trial design uses validated software to determine vaccine efficacy and a novel methodology to evaluate a new PrEP agent, overcoming the challenge of demonstrating non-inferiority when adherence to TDF/FTC is high and the number of outcome events very low.

As the HIV-positive population ages, new dangers loom: Researchers are exploring human immunodeficiency virus-mediated inflammation and immune dysregulation to better understand the higher risks of cancer, cardiovascular disease, and other conditions among individuals who carry the virus.

As the HIV-positive population ages, new dangers loom: Researchers are exploring human immunodeficiency virus-mediated inflammation and immune dysregulation to better understand the higher risks of cancer, cardiovascular disease, and other conditions among individuals who carry the virus.

Executive Functions Rating Scale and Neurobiochemical Profile in HIV-Positive Individuals.

The set of complex cognitive processes, that are necessary for the cognitive control of behavior, known as executive functions (EF), are traditionally associated with the prefrontal cortex and commonly assessed with laboratory based tests and conventional neuroimaging. In an effort to produce a more complete and ecologically valid understanding of executive functioning, the rating scales have been developed in order to assess the behavioral aspects of EF within an everyday real-world context. The main objective of this study was to examine the relationship between behavioral aspects of EF measured by rating scale and neurometabolic profile in neurologically asymptomatic HIV-positive individuals under cART, measured using multi-voxel magnetic resonance spectroscopy (mvMRS). The sample comprised 39 HIV-positive adult male participants, stable on cART and 39 healthy HIV-negative volunteers. Both groups completed the Behavior Rating Inventory of Executive Function-Adult Version (BRIEF-A). HIV-positive group additionally underwent long-echo three-dimensional mvMRS to determine neurobiochemical profile in the anterior cingulate gyrus (ACG) of both hemispheres. Three dominant neurometabolites were detected: N-acetyl aspartate (NAA), the neuronal marker; choline (Cho), the marker of membrane metabolism and gliosis and creatine (Cr), the reference marker. Ratios of NAA/Cr and Cho/Cr were analyzed. The initially detected significant correlations between age, current CD4, BRIEF-A subscales Inhibit, Shift, Emotional Control, Plan/Organize, Self Monitoring and ratios of NAA/Cr and Cho/Cr in the dorsal and ventral part of the ACG, were lost after the introduction of Bonferroni corrections. Also, there were no significant differences between HIV–positive and HIV–negative group on any of BRIEF-A subscales. Such results possibly imply that stable cART regimen contributes to preservation of behavioral aspects of EF in asymptomatic HIV-positive individuals. Even though a subtle deficit in some aspects of EF might exist, it would not be manifest if behavioral aspect was assessed using EF rating scale. Further explanation might be that expected HIV-related changes in neurometabolic profile of the ACG under cART are not reflected in those behavioral aspects that are measurable by EF rating scale.

EFFECTS OF COMBRETUM HEREROENSE AND CANTHIUMMUNDIANUM water EXTRACTS ON PRODUCTION AND EXPRESSION OF INTERLEUKIN-4.

Background:Combretum hereroense and Canthium mundianum are two plants commonly used by traditional healers in the Northern region of Limpopo, South Africa for the treatment of diarrhea and inflammation. In the present study, the effects of their water extracts on the production and expression of interleukin-4 by peripheral blood mononuclear cells (PBMC’S) from HIV positive and negative individuals was evaluated.Materials and methods:Blood samples were collected from both HIV positive and HIV negative volunteers and were used for the purification of Peripheral blood mononuclear cells (PBMC). The PBMCs were cultured together with the water extracts after activation with phytohemagglutinin (PHA) for three days. Solid-phase sandwich ELISA (MABTECH) kit was used to detect IL-4 on un-stimulated and stimulated PBMC’S with phytohemaglutinin (PHA) and plant extracts, followed by the isolation of RNA using RNAesy Qiagen mini kit from the cells. Reverse transcriptase real time PCR was used to evaluate IL-4 gene expression by the cells.Results:Combretum hereroense showed higher production of IL-4 at three different concentrations and a significant expression of mRNA with 4-fold amplification increase at 300μg/ml and 2-fold amplification increase at 20μg/ml. Canthium mundianum also showed increased production of IL-4 at 300μg/ml, but inhibited its production at 20μg/ml. Both extracts showed no expression at 50μg/ml. The response of the PBMCs from HIV negative individuals was more pronounced than that of HIV positive individuals who mostly increased production of IL4 at smaller concentrations unlike their HIV negative counterparts. Although in vitro studies do not necessarily predict in vivo outcomes, the plant extracts modulated the immune system by enhancing the production and expression of IL-4 in both HIV- and HIV+ individuals at different concentrations.Conclusions:For the first time we have shown that the immunomodulatory effect of medicinal plants may depend on the clinical status of the individual. The present study revealed that the effect of the water extracts from the two plants on IL-4 expression and production is dependent on the microbiological state of the individual and is dose dependent. Further studies are needed to identify the active components in the extracts and also characterize the patients further for a better understanding of the mechanisms of action of these extracts.

Allele and Genotype Frequencies of Cytochrome P450 2B6 516G>T Single Nucleotide Polymorphism in HIV-Negative and HIV-Infected Adult Nigerian Populations.

Polymorphisms in genes have been found in most enzymes involved in drug metabolism, especially in the cytochrome P450 (CYP) family with considerable ethnic differences in their frequencies. Single nucleotide polymorphisms (SNPs) are the major source of these genetic variations. CYP2B6 516G>T SNP found in both CYP2B6*6 and CYP2B6*9 alleles significantly reduces CYP2B6 protein expression and enzyme activity with important implications on the pharmacokinetics and pharmacodynamic outcomes of some clinically relevant drug substrates. This study determined the frequencies of CYP2B6 516G>T SNP in HIV-negative and HIV-infected adult Nigerian populations. Three hundred unrelated subjects (150 each of HIV-negative volunteers and HIV-infected patients) of different Nigerian ethnic groups residing in Ilorin and Ile-Ife and its environs, respectively, were recruited and genotyped for their CYP2B6 516G>T genetic status using real-time polymerase chain reaction. Differences in allele and genotype frequencies between both populations were tested using Pearson χ test. Minor allele frequency of 36.4% and genotype frequencies of 38.7% GG, 50.0% GT, 11.3% TT and a minor allele frequency of 37.0% and genotype frequencies of 42.0% GG, 42.0% GT, 16.0% TT were obtained for the HIV-negative volunteers and HIV-infected patients, respectively. χ test indicated a significant relationship between genotype frequencies in both populations (P < 0.001). The minor allele and genotype frequencies obtained in the 2 populations significantly differ and corroborate previous studies, which have reported CYP2B6 516G>T SNP in various other African populations.

HIV-1 Alters Intestinal Expression of Drug Transporters and Metabolic Enzymes: Implications for Antiretroviral Drug Disposition

This study investigated the effects of HIV-1 infection and antiretroviral therapy (ART) on the expression of intestinal drug efflux transporters, i.e., P-glycoprotein (Pgp), multidrug resistance-associated proteins (MRPs), and breast cancer resistance protein (BCRP), and metabolic enzymes, such as cytochrome P450s (CYPs), in the human upper intestinal tract. Intestinal biopsy specimens were obtained from HIV-negative healthy volunteers, ART-naive HIV-positive (HIV(+)) subjects, and HIV(+) subjects receiving ART (10 in each group). Intestinal tissue expression of drug transporters and metabolic enzymes was examined by microarray, real-time quantitative reverse transcription-PCR (qPCR), and immunohistochemistry analyses. Microarray analysis demonstrated significantly lower expression of CYP3A4 and ABCC2/MRP2 in the HIV(+) ART-naive group than in uninfected subjects. qPCR analysis confirmed significantly lower expression of ABCC2/MRP2 in ART-naive subjects than in the control group, while CYP3A4 and ABCG2/BCRP showed a trend toward decreased expression. Protein expression of MRP2 and BCRP was also significantly lower in the HIV(+) naive group than in the control group and was partially restored to baseline levels in HIV(+) subjects receiving ART. In contrast, gene and protein expression of ABCB1/Pgp was significantly increased in HIV(+) subjects on ART relative to HIV(+) ART-naive subjects. These data demonstrate that the expression of drug-metabolizing enzymes and efflux transporters is significantly altered in therapy-naive HIV(+) subjects and in those receiving ART. Since CYP3A4, Pgp, MRPs, and BCRP metabolize or transport many antiretroviral drugs, their altered expression with HIV infection may negatively impact drug pharmacokinetics in HIV(+) subjects. This has clinical implications when using data from healthy volunteers to guide ART.

Factors associated with iohexol-based glomerular filtration rate slope over 36 months in HIV-negative and HIV-positive individuals.

Monitoring kidney function is important in HIV-positive persons, but creatinine-based estimates of glomerular filtration rate (GFR) have limitations. There are little to no data available assessing GFR trends in HIV-positive persons using a gold-standard measure of GFR. We measured GFR based on iohexol plasma disappearance (iGFR) annually for 3 years in nondiabetic, HIV-negative and HIV-positive volunteers with normal estimated kidney function. We used mixed linear models to evaluate factors associated with baseline iGFR and iGFR slope. One hundred HIV-negative and 191 HIV-positive, predominantly black individuals (median age 49 years) participated in the study and completed a total of 960 iGFR assessments over a median of 36 months. Despite similar estimated GFR at baseline, average iGFR values were lower in HIV-positive compared with HIV-negative participants (103.2 vs. 110.8, ml/min/1.73 m, P = 0.004). However, subsequent iGFR slope was not significantly different in HIV-positive and HIV-negative participants. In the HIV-positive group, the presence of carotid plaque and hepatitis C virus coinfection were associated with significantly lower iGFR values at baseline. A nonsuppressed HIV RNA level at baseline was associated with a significantly more rapid iGFR decline compared with individuals with HIV RNA less than 400 copies/ml (-4.69 vs. -1.31 ml/min per 1.73 m per year, P = 0.005). Other factors significantly associated with iGFR slope included albuminuria and glycosylated hemoglobin. Compared with HIV-negative persons, HIV-positive participants had significantly lower baseline iGFR, despite similar estimated GFR in the two groups. Nonsuppressed HIV RNA at baseline was associated with a more rapid iGFR decline over 3 years.

Dolutegravir and elvitegravir plasma concentrations following cessation of drug intake.

To evaluate dolutegravir and elvitegravir/cobicistat pharmacokinetics in HIV-negative volunteers up to 10 days after drug cessation. Healthy volunteers received 50 mg of dolutegravir once-daily for 10 days, then underwent a 9 day wash-out period, and then received elvitegravir/cobicistat as part of Stribild(®) (245 mg of tenofovir, 200 mg of emtricitabine, 150 mg of elvitegravir and 150 mg of cobicistat) for 10 days. Serial pharmacokinetic (PK) sampling occurred prior to the final dose of each course and at regular intervals for up to 216 h (10 days) after drug cessation. Concentrations were determined by LC-MS/MS, and PK parameters were illustrated as geometric mean and 90% CI. Seventeen volunteers completed the study. For dolutegravir, plasma terminal elimination t1/2 to the last measurable concentration (within 216 h) was longer than its t1/2 within the dosing interval (0-24 h): 14.3 h (12.9-15.7 h) versus 23.1 h (19.7-26.6 h); conversely, the terminal elimination t1/2 for elvitegravir was lower than its t1/2 within the dosing interval (0-24 h): 10.8 h (9.7-13.0 h) versus 5.2 h (4.7-6.1 h). Dolutegravir concentrations were above the protein-adjusted (PA) IC90 (64 ng/mL) in 100% of subjects after 36 and 48 h and in 94% after 60 and 72 h. All subjects had detectable dolutegravir concentrations at 96 h, a mean of 23.5% above the IC90. Elvitegravir concentrations were above the PA IC95 (45 ng/mL) in 100% of subjects at 24 h, 65% at 36 h but 0% after 48 h. Our data show marked differences in the elimination rates of dolutegravir and elvitegravir following treatment interruption, which is likely to impact the extent to which drug doses can be delayed or missed. They suggest that clinical differences may emerge in patients who have suboptimal adherence.

Plasma lipidomic profiling of treated HIV-positive individuals and the implications for cardiovascular risk prediction.

BackgroundThe increased risk of coronary artery disease in human immunodeficiency virus (HIV) positive patients is collectively contributed to by the human immunodeficiency virus and antiretroviral-associated dyslipidaemia. In this study, we investigate the characterisation of the plasma lipid profiles of treated HIV patients and the relationship of 316 plasma lipid species across multiple lipid classes with the risk of future cardiovascular events in HIV- positive patients.MethodsIn a retrospective case-control study, we analysed plasma lipid profiles of 113 subjects. Cases (n = 23) were HIV-positive individuals with a stored blood sample available 12 months prior to their diagnosis of coronary artery disease (CAD). They were age and sex matched to HIV-positive individuals without a diagnosis of CAD (n = 45) and with healthy HIV-negative volunteers (n = 45).ResultsAssociation of plasma lipid species and classes with HIV infection and cardiovascular risk in HIV were determined. In multiple logistic regression, we identified 83 lipids species and 7 lipid classes significantly associated with HIV infection and a further identified 74 lipid species and 8 lipid classes significantly associated with future cardiovascular events in HIV-positive subjects. Risk prediction models incorporating lipid species attained an area under the receiver operator characteristic curve (AUC) of 0.78 (0.775, 0.785)) and outperformed all other tested markers and risk scores in the identification of HIV-positive subjects with increased risk of cardiovascular events.ConclusionsOur results demonstrate that HIV-positive patients have significant differences in their plasma lipid profiles compared with healthy HIV-negative controls and that numerous lipid species were significantly associated with elevated cardiovascular risk. This suggests a potential novel application for plasma lipids in cardiovascular risk screening of HIV-positive patients.

Vitamin D levels among HIV-infected patients – peculiar features

Methods We performed a descriptive, cross-sectional study on a group of 68 HIV-infected patients monitored in the Regional HIV/AIDS Centre Mures, during December 2012-February 2013. We determined plasma levels of 25[OH]D. We estimated the proportion of patients with 25[OH]D deficiency/insufficiency and correlated 25[OH] D levels to HIV-RNA plasma viral load, CD4+ T-cells count and associated pathology. Data were compared to those obtained from a group of healthy, HIV-negative volunteers. Statistical analysis was performed using the GraphPad program.