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38 result(s) for "Sneller, Michael C"
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Effect of analytical treatment interruption and reinitiation of antiretroviral therapy on HIV reservoirs and immunologic parameters in infected individuals
Therapeutic strategies aimed at achieving antiretroviral therapy (ART)-free HIV remission in infected individuals are under active investigation. Considering the vast majority of HIV-infected individuals experience plasma viral rebound upon cessation of therapy, clinical trials evaluating the efficacy of curative strategies would likely require inclusion of ART interruption. However, it is unclear what impact short-term analytical treatment interruption (ATI) and subsequent reinitiation of ART have on immunologic and virologic parameters of HIV-infected individuals. Here, we show a significant increase of HIV burden in the CD4+ T cells of infected individuals during ATI that was correlated with the level of plasma viral rebound. However, the size of the HIV reservoirs as well as immune parameters, including markers of exhaustion and activation, returned to pre-ATI levels 6-12 months after the study participants resumed ART. Of note, the proportions of near full-length, genome-intact and structurally defective HIV proviral DNA sequences were similar prior to ATI and following reinitiation of ART. In addition, there was no evidence of emergence of antiretroviral drug resistance mutations within intact HIV proviral DNA sequences following reinitiation of ART. These data demonstrate that short-term ATI does not necessarily lead to expansion of the persistent HIV reservoir nor irreparable damages to the immune system in the peripheral blood, warranting the inclusion of ATI in future clinical trials evaluating curative strategies.
Ebola virus disease-related stigma among survivors declined in Liberia over an 18-month, post-outbreak period: An observational cohort study
While qualitative assessments of Ebola virus disease (EVD)-related stigma have been undertaken among survivors and the general public, quantitative tools and assessment targeting survivors have been lacking. Beginning in June 2015, EVD survivors from seven Liberian counties, where most of the country's EVD cases occurred, were eligible to enroll in a longitudinal cohort. Seven stigma questions were adapted from the People Living with HIV Stigma Index and asked to EVD survivors over the age of 12 at initial visit (median 358 days post-EVD) and 18 months later. Primary outcome was a 7-item EVD-related stigma index. Explanatory variables included age, gender, educational level, pregnancy status, post-EVD hospitalization, referred to medical care and EVD source. Proportional odds logistic regression models and generalized linear mixed-effects models were used to assess stigma at initial visit and over time. The stigma questions were administered to 859 EVD survivors at initial visit and 741 (86%) survivors at follow-up. While 63% of survivors reported any stigma at initial visit, only 5% reported any stigma at follow-up. Over the 18-month period, there was a significant decrease in stigma among EVD survivors (Adjusted Odds Ratio [AOR], 0.02; 95% Confidence Interval [CI], 0.01-0.04). At initial visit, having primary, junior high or vocational education, and being referred to medical care was associated with higher odds of stigma (educational level: AOR, 1.82; 95%CI, 1.27-2.62; referred: AOR, 1.50; 95%CI, 1.16-1.94). Compared to ages of 20-29, those who had ages of 12-19 or 50+ experienced lower odds of stigma (12-19: AOR, 0.32; 95%CI, 0.21-0.48; 50+: AOR, 0.58 95%CI, 0.37-0.91). Our data suggest that EVD-related stigma was much lower more than a year after active Ebola transmission ended in Liberia. Among survivors who screened negative for stigma, additional probing may be considered based on age, education, and referral to care.
The impact of the 2014 Ebola epidemic on HIV disease burden and outcomes in Liberia West Africa
Detailed longitudinal studies of HIV-positive individuals in West Africa are lacking. Here the HIV prevalence, incidence, all-cause mortality, and the proportion of individuals receiving treatment with cART in two cohorts of participants in Ebola-related studies are described. Individuals of all ages were enrolled and followed at four sites in the area of Monrovia, Liberia. Two cohorts identified in response to the Ebola epidemic are described to provide insights into the current state of the HIV epidemic. HIV testing was performed at baseline for participants in both cohorts and during follow-up in one cohort. Prevalence and incidence of HIV (prevalence of 3.1% for women and 1.4% for men and incidence of 3.3 per 1,000) were higher in these cohorts compared to 2018 national estimates (prevalence of 1.3% and incidence of 0.39 per 1,000). Most participants testing positive did not know their status prior to testing. Of those who knew they were HIV positive, 7.9% reported being on antiretroviral treatment. The death rate among those with HIV was 12.3% compared to 1.9% in HIV-negative individuals (adjusted odds ratio of 6.87). While higher levels of d-dimer were associated with increased mortality, this was not specific to those with HIV, however lower hemoglobin levels were associated with increased mortality among those with HIV. These findings point to a need to perform further research studies aimed at fulfilling these knowledge gaps and address current shortcomings in the provision of care for those living with HIV in Liberia.
Impact of Treatment Interruption on HIV Reservoirs and Lymphocyte Subsets in Individuals Who Initiated Antiretroviral Therapy During the Early Phase of Infection
Therapeutic strategies for achieving sustained virologic remission are being explored in human immunodeficiency virus (HIV)–infected individuals who began antiretroviral therapy (ART) during the early phase of infection. In the evaluation of such therapies, clinical protocols should include analytical treatment interruption (ATI); however, the immunologic and virologic impact of ATI in individuals who initiated ART early has not been fully delineated. We demonstrate that ATI causes neither expansion of HIV reservoirs nor immunologic abnormalities following reinitiation of ART. Our findings support the use of ATI to determine whether sustained virologic remission has been achieved in clinical trials of individuals who initiated ART early during HIV infection.
Scalable, semi-automated fluorescence reduction neutralization assay for qualitative assessment of Ebola virus-neutralizing antibodies in human clinical samples
Antibody titers against a viral pathogen are typically measured using an antigen binding assay, such as an enzyme-linked immunosorbent assay (ELISA), which only measures the ability of antibodies to identify a viral antigen of interest. Neutralization assays measure the presence of virus-neutralizing antibodies in a sample. Traditional neutralization assays, such as the plaque reduction neutralization test (PRNT), are often difficult to use on a large scale due to being both labor and resource intensive. Here we describe an Ebola virus fluorescence reduction neutralization assay (FRNA), which tests for neutralizing antibodies, that requires only a small volume of sample in a 96-well format and is easy to automate. The readout of the FRNA is the percentage of Ebola virus-infected cells measured with an optical reader or overall chemiluminescence that can be generated by multiple reading platforms. Using blinded human clinical samples (EVD survivors or contacts) obtained in Liberia during the 2013-2016 Ebola virus disease outbreak, we demonstrate there was a high degree of agreement between the FRNA-measured antibody titers and the Filovirus Animal Non-clinical Group (FANG) ELISA titers with the FRNA providing information on the neutralizing capabilities of the antibodies.
Increased Likelihood of Detecting Ebola Virus RNA in Semen by Using Sample Pelleting
Ebola virus RNA can reside for months or years in semen of survivors of Ebola virus disease and is probably associated with increased risk for cryptic sexual transmission of the virus. A modified protocol resulted in increased detection of Ebola virus RNA in semen and improved disease surveillance.
Combination anti-HIV antibodies provide sustained virological suppression
Antiretroviral therapy is highly effective in suppressing human immunodeficiency virus (HIV) 1 . However, eradication of the virus in individuals with HIV has not been possible to date 2 . Given that HIV suppression requires life-long antiretroviral therapy, predominantly on a daily basis, there is a need to develop clinically effective alternatives that use long-acting antiviral agents to inhibit viral replication 3 . Here we report the results of a two-component clinical trial involving the passive transfer of two HIV-specific broadly neutralizing monoclonal antibodies, 3BNC117 and 10-1074. The first component was a randomized, double-blind, placebo-controlled trial that enrolled participants who initiated antiretroviral therapy during the acute/early phase of HIV infection. The second component was an open-label single-arm trial that enrolled individuals with viraemic control who were naive to antiretroviral therapy. Up to 8 infusions of 3BNC117 and 10-1074, administered over a period of 24 weeks, were well tolerated without any serious adverse events related to the infusions. Compared with the placebo, the combination broadly neutralizing monoclonal antibodies maintained complete suppression of plasma viraemia (for up to 43 weeks) after analytical treatment interruption, provided that no antibody-resistant HIV was detected at the baseline in the study participants. Similarly, potent HIV suppression was seen in the antiretroviral-therapy-naive study participants with viraemia carrying sensitive virus at the baseline. Our data demonstrate that combination therapy with broadly neutralizing monoclonal antibodies can provide long-term virological suppression without antiretroviral therapy in individuals with HIV, and our experience offers guidance for future clinical trials involving next-generation antibodies with long half-lives. Combination therapy of broadly neutralizing monoclonal antibodies can provide long-term virological suppression in individuals infected with HIV without antiretroviral therapy.
Prolonged viral suppression with anti-HIV-1 antibody therapy
HIV-1 infection remains a public health problem with no cure. Anti-retroviral therapy (ART) is effective but requires lifelong drug administration owing to a stable reservoir of latent proviruses integrated into the genome of CD4 + T cells 1 . Immunotherapy with anti-HIV-1 antibodies has the potential to suppress infection and increase the rate of clearance of infected cells 2 , 3 . Here we report on a clinical study in which people living with HIV received seven doses of a combination of two broadly neutralizing antibodies over 20 weeks in the presence or absence of ART. Without pre-screening for antibody sensitivity, 76% (13 out of 17) of the volunteers maintained virologic suppression for at least 20 weeks off ART. Post hoc sensitivity analyses were not predictive of the time to viral rebound. Individuals in whom virus remained suppressed for more than 20 weeks showed rebound viraemia after one of the antibodies reached serum concentrations below 10 µg ml −1 . Two of the individuals who received all seven antibody doses maintained suppression after one year. Reservoir analysis performed after six months of antibody therapy revealed changes in the size and composition of the intact proviral reservoir. By contrast, there was no measurable decrease in the defective reservoir in the same individuals. These data suggest that antibody administration affects the HIV-1 reservoir, but additional larger and longer studies will be required to define the precise effect of antibody immunotherapy on the reservoir. A clinical study shows that immunotherapy with anti-HIV-1 antibodies maintains prolonged viral suppression after anti-retroviral treatment is discontinued and affects the size and composition of the intact but not the defective proviral reservoir.
Rapid Emergence of T Follicular Helper and Germinal Center B Cells Following Antiretroviral Therapy in Advanced HIV Disease
Low nadir CD4 T-cell counts in HIV + patients are associated with high morbidity and mortality and lasting immune dysfunction, even after antiretroviral therapy (ART). The early events of immune recovery of T cells and B cells in severely lymphopenic HIV + patients have not been fully characterized. In a cohort of lymphopenic (CD4 T-cell count < 100/µL) HIV + patients, we studied mononuclear cells isolated from peripheral blood (PB) and lymph nodes (LN) pre-ART (n = 40) and 6-8 weeks post-ART (n = 30) with evaluation of cellular immunophenotypes; histology on LN sections; functionality of circulating T follicular helper (cTfh) cells; transcriptional and B-cell receptor profile on unfractionated LN and PB samples; and plasma biomarker measurements. A group of 19 healthy controls (HC, n = 19) was used as a comparator. T-cell and B-cell lymphopenia was present in PB pre-ART in HIV + patients. CD4:CD8 and CD4 T- and B-cell PB subsets partly normalized compared to HC post-ART as viral load decreased. Strikingly in LN, ART led to a rapid decrease in interferon signaling pathways and an increase in Tfh, germinal center and IgD - CD27 - B cells, consistent with histological findings of post-ART follicular hyperplasia. However, there was evidence of cTfh cells with decreased helper capacity and of limited B-cell receptor diversification post-ART. In conclusion, we found early signs of immune reconstitution, evidenced by a surge in LN germinal center cells, albeit limited in functionality, in HIV + patients who initiate ART late in disease.