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1.
Malar J ; 22(1): 32, 2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36707795

RESUMEN

BACKGROUND: When people with human immunodeficiency virus (HIV) infection (PWH) develop malaria, they are at risk of poor anti-malarial treatment efficacy resulting from impairment in the immune response and/or drug-drug interactions that alter anti-malarial metabolism. The therapeutic efficacy of artemether-lumefantrine was evaluated in a cohort of PWH on antiretroviral therapy (ART) and included measurement of day 7 lumefantrine levels in a subset to evaluate for associations between lumefantrine exposure and treatment response. METHODS: Adults living with HIV (≥ 18 years), on ART for ≥ 6 months with undetectable HIV RNA viral load and CD4 count ≥ 250/mm3 were randomized to daily trimethoprim-sulfamethoxazole (TS), weekly chloroquine (CQ) or no prophylaxis. After diagnosis of uncomplicated Plasmodium falciparum malaria, a therapeutic efficacy monitoring was conducted with PCR-correction according to WHO guidelines. The plasma lumefantrine levels on day 7 in 100 episodes of uncomplicated malaria was measured. A frailty proportional hazards model with random effects models to account for clustering examined the relationship between participant characteristics and malaria treatment failure within 28 days. Pearson's Chi-squared test was used to compare lumefantrine concentrations among patients with treatment failure and adequate clinical and parasitological response (ACPR). RESULTS: 411 malaria episodes were observed among 186 participants over 5 years. The unadjusted ACPR rate was 81% (95% CI 77-86). However, after PCR correction to exclude new infections, ACPR rate was 94% (95% CI 92-97). Increasing age and living in Ndirande were associated with decreased hazard of treatment failure. In this population of adults with HIV on ART, 54% (51/94) had levels below a previously defined optimal day 7 lumefantrine level of 200 ng/ml. This occurred more commonly among participants who were receiving an efavirenz-based ART compared to other ART regimens (OR 5.09 [95% CI 1.52-7.9]). Participants who experienced treatment failure had lower day 7 median lumefantrine levels (91 ng/ml [95% CI 48-231]) than participants who experienced ACPR (190 ng/ml [95% CI 101-378], p-value < 0.008). CONCLUSION: Recurrent malaria infections are frequent in this population of PWH on ART. The PCR-adjusted efficacy of AL meets the WHO criteria for acceptable treatment efficacy. Nevertheless, lumefantrine levels tend to be low in this population, particularly in those on efavirenz-based regimens, with lower concentrations associated with more frequent malaria infections following treatment. These results highlight the importance of understanding drug-drug interactions when diseases commonly co-occur.


Asunto(s)
Antimaláricos , Artemisininas , Infecciones por VIH , Malaria Falciparum , Malaria , Humanos , Adulto , Antimaláricos/uso terapéutico , Malaui , Artemisininas/uso terapéutico , Arteméter/uso terapéutico , Combinación de Medicamentos , Combinación Arteméter y Lumefantrina/uso terapéutico , Malaria/tratamiento farmacológico , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/prevención & control , Lumefantrina/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Resultado del Tratamiento , Etanolaminas/uso terapéutico , Fluorenos/uso terapéutico
2.
Clin Infect Dis ; 74(11): 2010-2019, 2022 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-34453519

RESUMEN

BACKGROUND: Organ transplantation from donors with human immunodeficiency virus (HIV) to recipients with HIV (HIV D+/R+) presents risks of donor-derived infections. Understanding clinical, immunologic, and virologic characteristics of HIV-positive donors is critical for safety. METHODS: We performed a prospective study of donors with HIV-positive and HIV false-positive (FP) test results within the HIV Organ Policy Equity (HOPE) Act in Action studies of HIV D+/R+ transplantation (ClinicalTrials.gov NCT02602262, NCT03500315, and NCT03734393). We compared clinical characteristics in HIV-positive versus FP donors. We measured CD4 T cells, HIV viral load (VL), drug resistance mutations (DRMs), coreceptor tropism, and serum antiretroviral therapy (ART) detection, using mass spectrometry in HIV-positive donors. RESULTS: Between March 2016 and March 2020, 92 donors (58 HIV positive, 34 FP), representing 98.9% of all US HOPE donors during this period, donated 177 organs (131 kidneys and 46 livers). Each year the number of donors increased. The prevalence of hepatitis B (16% vs 0%), syphilis (16% vs 0%), and cytomegalovirus (CMV; 91% vs 58%) was higher in HIV-positive versus FP donors; the prevalences of hepatitis C viremia were similar (2% vs 6%). Most HIV-positive donors (71%) had a known HIV diagnosis, of whom 90% were prescribed ART and 68% had a VL <400 copies/mL. The median CD4 T-cell count (interquartile range) was 194/µL (77-331/µL), and the median CD4 T-cell percentage was 27.0% (16.8%-36.1%). Major HIV DRMs were detected in 42%, including nonnucleoside reverse-transcriptase inhibitors (33%), integrase strand transfer inhibitors (4%), and multiclass (13%). Serum ART was detected in 46% and matched ART by history. CONCLUSION: The use of HIV-positive donor organs is increasing. HIV DRMs are common, yet resistance that would compromise integrase strand transfer inhibitor-based regimens is rare, which is reassuring regarding safety.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , Antirretrovirales/uso terapéutico , VIH , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Seropositividad para VIH/tratamiento farmacológico , Humanos , Integrasas , Estudios Prospectivos , Donantes de Tejidos , Estados Unidos/epidemiología , Carga Viral
3.
J Clin Microbiol ; 59(2)2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33139419

RESUMEN

Accurate serological assays to detect antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are needed to characterize the epidemiology of SARS-CoV-2 infection and identify potential candidates for coronavirus disease 2019 (COVID-19) convalescent plasma (CCP) donation. This study compared the performances of commercial enzyme immunoassays (EIAs) with respect to detection of IgG or total antibodies to SARS-CoV-2 and neutralizing antibodies (nAbs). The diagnostic accuracy of five commercially available EIAs (Abbott, Euroimmun, EDI, ImmunoDiagnostics, and Roche) for detection of IgG or total antibodies to SARS-CoV-2 was evaluated using cross-sectional samples from potential CCP donors who had prior molecular confirmation of SARS-CoV-2 infection (n = 214) and samples from prepandemic emergency department patients without SARS-CoV-2 infection (n = 1,099). Of the 214 potential CCP donors, all were sampled >14 days since symptom onset and only a minority (n = 16 [7.5%]) had been hospitalized due to COVID-19; 140 potential CCP donors were tested by all five EIAs and a microneutralization assay. Performed according to the protocols of the manufacturers to detect IgG or total antibodies to SARS-CoV-2, the sensitivity of each EIA ranged from 76.4% to 93.9%, and the specificity of each EIA ranged from 87.0% to 99.6%. Using a nAb titer cutoff value of ≥160 as the reference representing a positive test result (n = 140 CCP donors), the empirical area under the receiver operating curve for each EIA ranged from 0.66 (Roche) to 0.90 (Euroimmun). Commercial EIAs with high diagnostic accuracy to detect SARS-CoV-2 antibodies did not necessarily have high diagnostic accuracy to detect high nAb titers. Some but not all commercial EIAs may be useful in the identification of individuals with high nAb titers among convalescent individuals.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Prueba Serológica para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/aislamiento & purificación , COVID-19/sangre , Estudios Transversales , Humanos , Sueros Inmunes/inmunología , Técnicas para Inmunoenzimas , Inmunoglobulina G/sangre , Pruebas de Neutralización , SARS-CoV-2/inmunología , Sensibilidad y Especificidad
4.
J Clin Microbiol ; 59(2)2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33208477

RESUMEN

Rapid point-of-care tests (POCTs) for detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific antibodies vary in performance. A critical need exists to perform head-to-head comparisons of these assays. The performances of 15 different lateral flow POCTs for the detection of SARS-CoV-2-specific antibodies were compared on a well-characterized set of 100 samples. Of these, 40 samples from known SARS-CoV-2-infected, convalescent individuals (collected an average of 45 days after symptom onset) were used to assess sensitivity. Sixty samples from the prepandemic era (negative control) that were known to represent infections with other respiratory viruses (rhinoviruses A, B, and C and/or coronavirus 229E, HKU1, and NL63 OC43) were used to assess specificity. The timing of seroconversion was assessed using five lateral flow assays (LFAs) and a panel of 272 longitudinal samples from 47 patients for whom the time since symptom onset was known. Among the assays that were evaluated, the sensitivity and specificity for any reactive band ranged from 55% to 97% and from 78% to 100%, respectively. Assessing the performance of the IgM and the IgG bands alone, sensitivity and specificity ranged from 0% to 88% and 80% to 100% for IgM and from 25% to 95% and 90% to 100% for IgG, respectively. Longitudinal testing revealed that the median times after symptom onset to a positive result were 7 days (interquartile range [IQR], 5.4 to 9.8) for IgM and 8.2 days (IQR, 6.3 to 11.3) for IgG. The testing performances differed widely among LFAs, with greatest amount of variation related to the sensitivity of the assays. The IgM band was the band most likely to misclassify prepandemic samples. The appearances of IgM and IgG bands occurred almost simultaneously.


Asunto(s)
Prueba Serológica para COVID-19/métodos , COVID-19/diagnóstico , Pruebas en el Punto de Atención , SARS-CoV-2/aislamiento & purificación , Anticuerpos Antivirales/sangre , COVID-19/sangre , Reacciones Cruzadas , Humanos , Inmunoensayo , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , SARS-CoV-2/inmunología , Sensibilidad y Especificidad , Seroconversión
5.
J Infect Dis ; 222(12): 1974-1984, 2020 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-32910175

RESUMEN

BACKGROUND: Convalescent plasma therapy is a leading treatment for conferring temporary immunity to COVID-19-susceptible individuals or for use as post-exposure prophylaxis. However, not all recovered patients develop adequate antibody titers for donation and the relationship between avidity and neutralizing titers is currently not well understood. METHODS: SARS-CoV-2 anti-spike and anti-nucleocapsid IgG titers and avidity were measured in a longitudinal cohort of COVID-19 hospitalized patients (n = 16 individuals) and a cross-sectional sample of convalescent plasma donors (n = 130). Epidemiologic correlates of avidity were examined in donors by linear regression. The association of avidity and a high neutralizing titer (NT) were also assessed in donors using modified Poisson regression. RESULTS: Antibody avidity increased over duration of infection and remained elevated. In convalescent plasma donors, higher levels of anti-spike avidity were associated with older age, male sex, and hospitalization. Higher NTs had a stronger positive correlation with anti-spike IgG avidity (Spearman ρ = 0.386; P < .001) than with anti-nucleocapsid IgG avidity (Spearman ρ = 0.211; P = .026). Increasing levels of anti-spike IgG avidity were associated with high NT (≥160) (adjusted prevalence ratio = 1.58 [95% confidence interval = 1.19-2.12]), independent of age, sex, and hospitalization. CONCLUSIONS: SARS-CoV-2 antibody avidity correlated with duration of infection and higher neutralizing titers, suggesting a potential alternative screening parameter for identifying optimal convalescent plasma donors.


Asunto(s)
Anticuerpos Neutralizantes/administración & dosificación , Anticuerpos Antivirales/administración & dosificación , Afinidad de Anticuerpos , COVID-19/terapia , Inmunoglobulina G/administración & dosificación , SARS-CoV-2 , Adolescente , Adulto , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Donantes de Sangre , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Inmunización Pasiva , Inmunoglobulina G/sangre , Modelos Lineales , Masculino , Persona de Mediana Edad , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto Joven , Sueroterapia para COVID-19
6.
EBioMedicine ; 102: 105040, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38485563

RESUMEN

BACKGROUND: The principal barrier to an HIV cure is the presence of the latent viral reservoir (LVR), which has been understudied in African populations. From 2018 to 2019, Uganda instituted a nationwide rollout of ART consisting of Dolutegravir (DTG) with two NRTI, which replaced the previous regimen of one NNRTI and the same two NRTI. METHODS: Changes in the inducible replication-competent LVR (RC-LVR) of ART-suppressed Ugandans with HIV (n = 88) from 2015 to 2020 were examined using the quantitative viral outgrowth assay. Outgrowth viruses were examined for viral evolution. Changes in the RC-LVR were analyzed using three versions of a Bayesian model that estimated the decay rate over time as a single, linear rate (model A), or allowing for a change at time of DTG initiation (model B&C). FINDINGS: Model A estimated the slope of RC-LVR change as a non-significant positive increase, which was due to a temporary spike in the RC-LVR that occurred 0-12 months post-DTG initiation (p < 0.005). This was confirmed with models B and C; for instance, model B estimated a significant decay pre-DTG initiation with a half-life of 6.9 years, and an ∼1.7-fold increase in the size of the RC-LVR post-DTG initiation. There was no evidence of viral failure or consistent evolution in the cohort. INTERPRETATION: These data suggest that the change from NNRTI- to DTG-based ART is associated with a significant temporary increase in the circulating RC-LVR. FUNDING: Supported by the NIH (grant 1-UM1AI164565); Gilead HIV Cure Grants Program (90072171); Canadian Institutes of Health Research (PJT-155990); and Ontario Genomics-Canadian Statistical Sciences Institute.


Asunto(s)
Pueblo de África Oriental , Infecciones por VIH , Inhibidores de Integrasa VIH , VIH-1 , Humanos , Antirretrovirales/uso terapéutico , Teorema de Bayes , Linfocitos T CD4-Positivos , Infecciones por VIH/tratamiento farmacológico , Inhibidores de Integrasa VIH/farmacología , Inhibidores de Integrasa VIH/uso terapéutico , Carga Viral , Latencia del Virus
7.
medRxiv ; 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37292785

RESUMEN

The principal barrier to an HIV cure is the presence of a latent viral reservoir (LVR) made up primarily of latently infected resting CD4+ (rCD4) T-cells. Studies in the United States have shown that the LVR decays slowly (half-life=3.8 years), but this rate in African populations has been understudied. This study examined longitudinal changes in the inducible replication competent LVR (RC-LVR) of ART-suppressed Ugandans living with HIV (n=88) from 2015-2020 using the quantitative viral outgrowth assay, which measures infectious units per million (IUPM) rCD4 T-cells. In addition, outgrowth viruses were examined with site-directed next-generation sequencing to assess for possible ongoing viral evolution. During the study period (2018-19), Uganda instituted a nationwide rollout of first-line ART consisting of Dolutegravir (DTG) with two NRTI, which replaced the previous regimen that consisted of one NNRTI and the same two NRTI. Changes in the RC-LVR were analyzed using two versions of a novel Bayesian model that estimated the decay rate over time on ART as a single, linear rate (model A) or allowing for an inflection at time of DTG initiation (model B). Model A estimated the population-level slope of RC-LVR change as a non-significant positive increase. This positive slope was due to a temporary increase in the RC-LVR that occurred 0-12 months post-DTG initiation (p<0.0001). This was confirmed with model B, which estimated a significant decay pre-DTG initiation with a half-life of 7.7 years, but a significant positive slope post-DTG initiation leading to a transient estimated doubling-time of 8.1 years. There was no evidence of viral failure in the cohort, or consistent evolution in the outgrowth sequences associated with DTG initiation. These data suggest that either the initiation of DTG, or cessation of NNRTI use, is associated with a significant temporary increase in the circulating RC-LVR.

8.
medRxiv ; 2020 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-32908987

RESUMEN

Accurate serological assays to detect antibodies to SARS-CoV-2 are needed to characterize the epidemiology of SARS-CoV-2 infection and identify potential candidates for COVID-19 convalescent plasma (CCP) donation. This study compared the performance of commercial enzyme immunoassays (EIAs) to detect IgG or total antibodies to SARS-CoV-2 and neutralizing antibodies (nAb). The diagnostic accuracy of five commercially available EIAs (Abbott, Euroimmun, EDI, ImmunoDiagnostics, and Roche) to detect IgG or total antibodies to SARS-CoV-2 was evaluated from cross-sectional samples of potential CCP donors that had prior molecular confirmation of SARS-CoV-2 infection for sensitivity (n=214) and pre-pandemic emergency department patients for specificity (n=1,102). Of the 214 potential CCP donors, all were sampled >14 days since symptom onset and only a minority had been hospitalized due to COVID-19 (n=16 [7.5%]); 140 potential CCP donors were tested by all five EIAs and a microneutralization assay. When performed according to the manufacturers' protocol to detect IgG or total antibodies to SARS-CoV-2, the sensitivity of each EIA ranged from 76.4% to 93.9%, and the specificity of each EIA ranged from 87.0% to 99.6%. Using a nAb titer cutoff of ≥160 as the reference positive test (n=140 CCP donors), the empirical area under receiver operating curve of each EIA ranged from 0.66 (Roche) to 0.90 (Euroimmun). Commercial EIAs with high diagnostic accuracy to detect SARS-CoV-2 antibodies did not necessarily have high diagnostic accuracy to detect high nAbs. Some but not all commercial EIAs may be useful in the identification of individuals with high nAbs in convalescent individuals.

9.
EClinicalMedicine ; 15: 14-22, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31709410

RESUMEN

BACKGROUND: The Eastern Cape province of South Africa has one of the highest burdens of HIV in the world. Emergency Departments (EDs) can serve as optimal clinical sites for the identification of new HIV infections and entry into care. We sought to determine the current burden of HIV disease among ED patients in the Eastern Cape. METHODS: We conducted a prospective cross-sectional observational study in the EDs of three Hospitals in the Eastern Cape province of South Africa from June 2017 to July 2018. All adult, non-critical patients presenting to the ED were systematically approached and offered a Point-Of-Care (POC) HIV test in accordance with South African guidelines. All HIV-positive individuals had their blood tested for the presence of antiretroviral therapy (ART) and the presence of viral suppression (≤ 1000 copies/ml). HIV incidence was estimated using a multi-assay algorithm, validated for a subtype C epidemic. FINDINGS: Of the 2901 patients for whom HIV status was determined (either known HIV-positive or underwent POC HIV testing), 811 (28.0%) were HIV positive, of which 234 (28.9%) were newly diagnosed. HIV prevalence was higher in Mthatha [34% (388/1134) at Mthatha Regional Hospital and 28% (142/512) at Nelson Mandela Academic Hospital], compared to Port Elizabeth [22% (281/1255) at Livingstone Hospital]. HIV incidence was estimated at 4.5/100 person-years (95% CI: 2.4, 6.50) for women and 1.5 (CI 0.5, 2.5) for men. Of all HIV positive individuals tested for ART (585), 54% (316/585) tested positive for the presence of ARTs, and for all HIV positive participants with viral load data (609), 49% (299/609) were found to be virally suppressed. INTERPRETATION: Our study not only observed a high prevalence and incidence of HIV among ED patients but also highlights significant attrition along the HIV care cascade for HIV positive individuals. Furthermore, despite developing an optimal testing environment, we were only able to enrol a small sub-set of the ED population. Given the high HIV prevalence and high attrition in the ED population, HIV services in the ED should also develop strategies that can accommodate large testing volumes and ART initiation.

10.
Oncotarget ; 8(61): 103415-103427, 2017 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-29262572

RESUMEN

The GATA3 transcription factor is one of the most frequently mutated genes in breast cancer. Heterozygous mutations, mostly frameshifts, are seen in 15% of estrogen receptor positive breast cancers, the subtype in which these mutations are almost exclusively found. Mouse studies have shown that Gata3 is critical for breast development and that GATA3 gene dosage affects breast tumor progression. Human patient data have shown that high Gata3 expression, a feature of luminal subtype breast cancers, is associated with a better prognosis. Although the frequency of GATA3 mutation suggests an important role in breast cancer development or progression, there is little understanding of how mutations in GATA3 affect its function in luminal breast epithelial cells and what gene expression changes result as a consequence of the mutations. Here, using gene editing, we have created two sets of isogenic human luminal breast cancer cell lines with and without a hotspot truncating GATA3 mutation. GATA3 mutation enhanced tumor growth in vivo but did not affect sensitivity to clinically used hormonal therapies or chemotherapeutic agents. We identified genes with upregulated and downregulated expression in GATA3 mutant cells, a subset of which was concordantly differentially expressed in GATA3 mutant primary luminal breast cancers. Addback of mutant GATA3 recapitulated mutation-specific gene expression changes and enhanced soft agar colony formation, suggesting a gain of function for the mutant protein.

11.
FEBS Open Bio ; 4: 121-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24490136

RESUMEN

Stable and soluble proteins are ideal candidates for functional and structural studies. Unfortunately, some proteins or enzymes can be difficult to isolate, being sometimes poorly expressed in heterologous systems, insoluble and/or unstable. Numerous methods have been developed to address these issues, from the screening of various expression systems to the modification of the target protein itself. Here we use a hydrophobic, aggregation-prone, phosphate-binding protein (HPBP) as a case study. We describe a simple and fast method that selectively uses ancestral mutations to generate a soluble, stable and functional variant of the target protein, here named sHPBP. This variant is highly expressed in Escherichia coli, is easily purified and its structure was solved at much higher resolution than its wild-type progenitor (1.3 versus 1.9 Å, respectively).

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