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1.
Global Health ; 18(1): 5, 2022 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-35065670

RESUMO

Diagnostic testing for the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection remains a challenge around the world, especially in low-middle-income countries (LMICs) with poor socio-economic backgrounds. From the beginning of the pandemic in December 2019 to August 2021, a total of approximately 3.4 billion tests were performed globally. The majority of these tests were restricted to high income countries. Reagents for diagnostic testing became a premium, LMICs either cannot afford or find manufacturers unwilling to supply them with expensive analytical reagents and equipment. From March to December 2020 obtaining testing kits for SARS-CoV-2 testing was a challenge. As the number of SARS-CoV-2 infection cases increases globally, large-scale testing still remains a challenge in LMICs. The aim of this review paper is to compare the total number and frequencies of SARS-CoV-2 testing in LMICs and high-income countries (HICs) using publicly available data from Worldometer COVID-19, as well as discussing possible interventions and cost-effective measures to increase testing capability in LMICs. In summary, HICs conducted more SARS-CoV-2 testing (USA: 192%, Australia: 146%, Switzerland: 124% and Canada: 113%) compared to middle-income countries (MICs) (Vietnam: 43%, South Africa: 29%, Brazil: 27% and Venezuela: 12%) and low-income countries (LICs) (Bangladesh: 6%, Uganda: 4% and Nigeria: 1%). Some of the cost-effective solutions to counteract the aforementioned problems includes using saliva instead of oropharyngeal or nasopharyngeal swabs, sample pooling, and testing high-priority groups to increase the number of mass testing in LMICs.


Assuntos
COVID-19 , SARS-CoV-2 , Teste para COVID-19 , Análise Custo-Benefício , Países em Desenvolvimento , Humanos
2.
Parasitol Res ; 121(8): 2421-2432, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35657426

RESUMO

Trichomonas vaginalis (T. vaginalis) is the most prevalent sexually transmitted infection (STI) globally. Metronidazole is the drug of choice for treating T. vaginalis infections although metronidazole-resistant T. vaginalis has been reported in clinical isolates. The purpose of this study was to determine the presence of mutations in nitroreductase genes associated with metronidazole resistance in vaginal swabs testing positive for T. vaginalis. This study included 385 human immunodeficiency virus (HIV)-positive pregnant women. Vaginal swabs were collected from consenting pregnant women and used for the detection of T. vaginalis using the TaqMan assay. From the vaginal swabs, nitroreductase genes ntr4 and ntr6 containing mutations associated with metronidazole resistance were amplified using a quantitative polymerase chain reaction (PCR) assay. To validate the PCR assay, T. vaginalis cultured isolates with known metronidazole resistance profiles were used as controls in the mutation detection assays. The prevalence of T. vaginalis in the study population was 12.2% (47/385). Mutations associated with resistance to metronidazole were detected in more than 40% of the samples tested, i.e. 21/47 (45%) and 24/47 (51%) for ntr4 and ntr6, respectively. A total of 19 samples (40%) carried mutations for both ntr4 and ntr6 genes associated with metronidazole resistance. The validation assays showed a positive correlation between phenotypic and genotypic resistance profiles. This study found a high prevalence of mutations associated with metronidazole resistance. This is concerning since metronidazole is currently used in the syndromic management of STIs in South Africa. Molecular-based assays for monitoring metronidazole resistance profiles using nitroreductase genes may serve as a feasible method for antimicrobial surveillance studies for T. vaginalis.


Assuntos
Tricomoníase , Vaginite por Trichomonas , Trichomonas vaginalis , Resistência a Medicamentos , Feminino , Humanos , Metronidazol/farmacologia , Metronidazol/uso terapêutico , Reação em Cadeia da Polimerase , Gravidez , Tricomoníase/tratamento farmacológico , Vaginite por Trichomonas/diagnóstico
3.
Antimicrob Agents Chemother ; 65(10): e0075921, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34280016

RESUMO

Antimicrobial resistance (AMR) is a major challenge to managing infectious diseases. Africa has the highest incidence of gonorrhoea, but there is a lack of comprehensive data from sparse surveillance programs. This study investigated the molecular epidemiology and AMR profiles of Neisseria gonorrhoeae isolates in KwaZulu-Natal province (KZN), South Africa. Repository isolates from patients attending public health care clinics for sexually transmitted infection (STI) care were used for phenotypic and genotypic analysis. An Etest was performed to determine antimicrobial susceptibility. Whole-genome sequencing (WGS) was used to determine epidemiology and to predict susceptibility by detecting resistance-associated genes and mutations. Among the 61 isolates, multiple sequence types were identified. Six isolates were novel, as determined by multilocus sequence typing. N. gonorrhoeae sequence typing for antimicrobial resistance (NG-STAR) determined 48 sequence types, of which 35 isolates had novel antimicrobial profiles. Two novel penA alleles and eight novel mtrR alleles were identified. Point mutations were detected in gyrA, parC, mtrR, penA, ponA, and porB1. This study revealed a high prevalence of AMR (penicillin 67%, tetracycline 89%, and ciprofloxacin 52%). However, spectinomycin, cefixime, ceftriaxone, and azithromycin remained 100% effective. This study is one of the first to comprehensively describe the epidemiology and AMR of N. gonorrhoeae in KZN, South Africa and Africa, using WGS. KZN has a wide strain diversity and most of these sequence types have been detected in multiple countries; however, more than half of our isolates have novel antimicrobial profiles. Continued surveillance is crucial to monitor the emergence of resistance to cefixime, ceftriaxone, and azithromycin.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ceftriaxona , Farmacorresistência Bacteriana/genética , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Neisseria gonorrhoeae/genética , África do Sul/epidemiologia
4.
Sex Transm Infect ; 97(1): 33-37, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32848051

RESUMO

OBJECTIVES: Genital herpes simplex virus (HSV) infections are common in South Africa and worldwide. While HSV-2 is known to cause genital lesions, HSV-1 is better known to cause oral infections. Due to the global rise in genital HSV-1 infections, we aimed to compare the genital cytokine environment associated with HSV-1 and HSV-2 infections and their relation to the proinflammatory genital immune environment associated with HIV risk in African women. METHODS: HSV-1 and HSV-2 DNA were detected by quantitative real-time PCR in menstrual cup specimens collected from 251 HIV-negative women participating in the CAPRISA 083 study in Durban, South Africa. HSV shedding was defined as detection at >150 copies/mL. Forty-eight cytokines were measured in genital fluid by multiplexed ELISA, and multivariable regression models determined associations between genital cytokines and HSV DNA detection. RESULTS: HSV-1 DNA detection (24/251 (9.6%)) and shedding (13/24 (54.2%)) was more common than HSV-2 (detection in 14/251 (5.6%), shedding in 0/14). None of the women with detectable HSV had evidence of genital lesions. HSV-2 DNA detection was associated with increased interleukin (IL)-18 and decreased cutaneous T-cell attracting chemokine concentrations, but only in univariable analysis. By contrast, in both univariable and multivariable analyses, the detection of HSV-1 DNA was associated with reduced concentrations of granulocyte-colony stimulating factor, IL-7, IL-4, platelet-derived growth factor-ßß and five proinflammatory cytokines associated with HIV risk: IL-6, IL-1ß, macrophage inflammatory protein (MIP)-1α, MIP-1ß and tumour necrosis factor-α. CONCLUSIONS: That HSV-1 DNA was more commonly detected and shed than HSV-2 emphasises the need for clinical screening of both viruses, not just HSV-2 in young women. Efforts to reduce genital inflammation may need to consider implementing additional strategies to mitigate a rise in HSV replication.


Assuntos
Colo do Útero/virologia , Citocinas , DNA Viral/análise , Herpes Genital/virologia , Herpesvirus Humano 1/genética , Herpesvirus Humano 2/genética , Eliminação de Partículas Virais , Adulto , Estudos Transversais , Feminino , Humanos , Estudo de Prova de Conceito , Reação em Cadeia da Polimerase em Tempo Real , África do Sul/epidemiologia , Adulto Jovem
5.
Sex Transm Infect ; 97(8): 555-565, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33608480

RESUMO

OBJECTIVES: STIs cause inflammation that is detrimental for both HIV risk and reproductive health. We assessed the impact of point-of-care (POC) STI testing, immediate treatment and expedited partner therapy (EPT) on genital tract cytokines among a cohort of young South African women. METHODS: HIV-negative women underwent POC testing for Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) by Xpert CT/NG and OSOM TV, and for bacterial vaginosis (BV) by microscopy. Women with STIs and/or BV received immediate treatment, EPT for STIs and retested after 6 and 12 weeks. Concentrations of 48 cytokines were measured in cervicovaginal fluid at each visit using multiplex ELISA technology. The impact of STI treatment on cytokine concentrations was assessed by multivariable linear mixed models and principal component analysis. RESULTS: The study enrolled 251 women with median age of 23 years (IQR 21-27). The prevalence of CT, NG and TV were 14.3%, 4.4% and 4.0%, and 34.3% had BV. Women with STIs or BV at baseline (n=94) had significantly higher concentrations of pro-inflammatory cytokines (interleukin (IL)-1α, IL-1ß, IL-6, tumour necrosis factor (TNF)-α, TNF-ß, IL-18 and macrophage inflammatory factor (MIF)) and chemokines (IL-8, IL-16, macrophage inflammatory protein (MIP)-1α, IFN-α2, monokine induced by gamma interferon (MIG), monocyte chemoattractant protein (MCP)-3, regulated on activation normal T cell expressed and secreted and eotaxin) compared with women without (n=157). STI treatment was strongly associated with reduced concentrations of pro-inflammatory cytokines IL-6 (p=0.004), IL-1ß (p=0.013), TNF-α (p=0.018) and chemokines MIG (p=0.008) and growth-related oncogene (GRO)-α (p=0.025). A lower Nugent score was associated with a reduction in pro-inflammatory cytokines IL-1α (p=0.003), TNF-related apoptosis-inducing ligand (p=0.004), MIF (p=0.010) and IL-18 (p<0.001), but an increase in chemokines MIG (p=0.020), GRO-α (p<0.001), IP-10 (p<0.001), MIP-1ß (p=0.008) and MCP-1 (p=0.005). Principal component analysis showed differences in STI and BV-related inflammatory profiles, but that resolution restored a profile consistent with vaginal health. CONCLUSIONS: A comprehensive STI intervention effectively reduced genital inflammation among young women, thereby improving vaginal health and potentially reducing HIV risk.


Assuntos
Citocinas/imunologia , Inflamação/imunologia , Testes Imediatos/normas , Infecções do Sistema Genital/imunologia , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/tratamento farmacológico , Vaginose Bacteriana/diagnóstico , Vaginose Bacteriana/tratamento farmacológico , Adolescente , Adulto , Antibacterianos/uso terapêutico , Estudos de Coortes , Citocinas/análise , Feminino , Humanos , Inflamação/tratamento farmacológico , Estudos Prospectivos , Infecções do Sistema Genital/tratamento farmacológico , Infecções do Sistema Genital/microbiologia , Infecções Sexualmente Transmissíveis/microbiologia , Vagina/efeitos dos fármacos , Vagina/microbiologia , Adulto Jovem
6.
Eur J Clin Microbiol Infect Dis ; 39(8): 1481-1485, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32193689

RESUMO

Diagnosis of bacterial vaginosis (BV) in resource-poor settings relies on semiquantitative microscopy algorithm such as the Nugent score (NS). We evaluated a quantitative real-time PCR (qPCR) assay to detect and quantify individual BV-associated bacterial communities. Vaginal swabs from 247 South African women attending an STI clinic were evaluated for BV using NS. We used qPCR to analyze DNA from vaginal swabs for eight BV-associated bacteria, Gardnerella vaginalis (GV), Prevotella bivia (PB), BV-associated bacteria 2 (BVAB2), Megasphaera-1 (M-1), Atopobium vaginae (AV), Lactobacillus crispatus (LC), Lactobacillus jensenii (LJ), and Lactobacillus iners (LI). Sensitivities and specificities were generated for each qPCR assay. Using a ROC analysis, cutoffs were calculated for each bacterial species. A logistic regression model was used to determine the strongest predictors of BV status. Nugent scores indicated 35.6% of patients harbor BV-associated flora (NS 7-10). AV, GV, GAMB (GV + AV + M-1 + BVAB2), and LC + LJ showed the highest AUC, sensitivities, and specificities (listed respectively): AV (0.96; 96%; 93%), GV (0.88; 78%; 79%), GAMB (0.9; 87%; 82%), and LC + LJ (0.84; 82%; 72%) (all p < 0.05). Increased GAMB copies (effect = 0.15, p = 0.01) and decreased LC + LJ copies (effect = - 0.26, p < 0.0001) demonstrated the strongest association with higher BV scoring. Scoring of BV did not differ across our qPCR assay when compared to the commercial BD MAX® and the gold standard Nugent scores. We developed an accurate assay, which has the potential to be used as a BV diagnosis tool that is cost-effective and has the potential to be utilized in a resource limited setting.


Assuntos
Vaginose Bacteriana/diagnóstico , Actinobacteria/isolamento & purificação , Adulto , Área Sob a Curva , DNA Bacteriano/análise , Feminino , Gardnerella vaginalis/isolamento & purificação , Humanos , Lactobacillus/isolamento & purificação , Valor Preditivo dos Testes , Prevotella/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Manejo de Espécimes , Vaginose Bacteriana/microbiologia , Adulto Jovem
7.
BMC Infect Dis ; 20(1): 491, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32650729

RESUMO

BACKGROUND: Bacterial vaginosis (BV) increases HIV risk and adverse reproductive outcomes. Standard-of-care (SOC) for BV are antibiotics; however, cure rates are low. Probiotics for vaginal health may be useful in improving cure and recurrence although the regulatory framework governing probiotics and the conduct of randomized clinical trials to evaluate these has not been established in South Africa. We performed an exploratory single-blind trial evaluating a commercial oral-vaginal-combination probiotic as adjunct to SOC for BV treatment. METHODS: Women with symptomatic vaginal discharge were screened for BV and common sexually transmitted infections (STIs). BV+ (Nugent 7-10) but STI- women were randomized to vaginal metronidazole alone (n = 12) or to metronidazole followed by a commercial oral/vaginal probiotic (n = 18). The primary qualitative outcome was to test the regulatory landscape for conducting randomized probiotic trials in South Africa; and acceptability of vaginal application by women. BV cure at 1 month (Nugent≤3) was the primary quantitative endpoint. Secondary quantitative endpoints were BV recurrence, symptoms, vaginal microbiota and genital cytokine changes over 5 months post-treatment. RESULTS: The  South African Health Products Regulatory Authority (SAHPRA) reviewed and approved this trial. As probiotics continue to be regulated as health supplements in South Africa, SAHPRA required a notification application for this trial. Acceptability and adherence to the oral and vaginal application of the probiotic were high, although women reported a preference for oral capsules. 44.8% of women cleared BV one-month post-treatment, and no significant differences in BV cure (RR = 0.52, 95% CI = 0.24-1.16), recurrence, vaginal pH, symptoms, microbiota or vaginal IL-1α concentrations were found between SOC and intervention groups in this pilot study with an over-the-counter product. CONCLUSION: Navigation of the SAHPRA registration process for evaluating a commercial probiotic in a randomised trial laid the foundation for planned larger trials of improved probiotic products for vaginal health in South Africa. Although adherence to the vaginally delivered probiotic was high, women preferred oral application and we recommend that improvements in the content and method of application for future probiotics for vaginal health should be considered. TRIAL REGISTRATION: This trial was registered on 17 October 2017 with the South African National Clinical Trial Register ( http://www.sanctr.gov.za/ ; BV-trial1; DOH-27-1117-5579 ).


Assuntos
Probióticos/uso terapêutico , Vaginose Bacteriana/microbiologia , Vaginose Bacteriana/terapia , Administração Intravaginal , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Suplementos Nutricionais , Aprovação de Drogas , Feminino , Humanos , Interleucina-1alfa/metabolismo , Adesão à Medicação , Metronidazol/administração & dosagem , Metronidazol/uso terapêutico , Microbiota , Projetos Piloto , Recidiva , Método Simples-Cego , África do Sul , Resultado do Tratamento , Adulto Jovem
8.
BMC Infect Dis ; 18(1): 54, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29370775

RESUMO

BACKGROUND: The majority of people living with HIV require antiretroviral therapy (ART) for controlling viral replication, however there are rare HIV controllers who spontaneously and durably control HIV in the absence of treatment. Understanding what mediates viral control in these individuals has provided us with insights into the immune mechanisms that may be important to induce for a vaccine or functional cure for HIV. To date, few African elite controllers from high incidence settings have been described. We identified virological controllers from the CAPRISA 002 cohort of HIV-1 subtype C infected women in KwaZulu Natal, South Africa, two (1%) of whom were elite controllers. We examined the genetic, clinical, immunological and virological characteristics of these two elite HIV controllers in detail, to determine whether they exhibit features of putative viral control similar to those described for elite controllers reported in the literature. CASE PRESENTATION: In this case report, we present clinical features, CD4+ T cell and viral load trajectories for two African women over 7 years of HIV infection. Viral load became undetectable 10 months after HIV infection in Elite Controller 1 (EC1), and after 6 weeks in Elite Controller 2 (EC2), and remained undetectable for the duration of follow-up, in the absence of ART. Both elite controllers expressed multiple HLA Class I and II haplotypes previously associated with slower disease progression (HLA-A*74:01, HLA-B*44:03, HLA-B*81:01, HLA-B*57:03, HLA-DRB1*13). Fitness assays revealed that both women were infected with replication competent viruses, and both expressed higher mRNA levels of p21, a host restriction factor associated with viral control. HIV-specific T cell responses were examined using flow cytometry. EC1 mounted high frequency HIV-specific CD8+ T cell responses, including a B*81:01-restricted Gag TL9 response. Unusually, EC2 had evidence of pre-infection HIV-specific CD4+ T cell responses. CONCLUSION: We identified some features typical of elite controllers, including high magnitude HIV-specific responses and beneficial HLA. In addition, we made the atypical finding of pre-infection HIV-specific immunity in one elite controller, that may have contributed to very early viral control. This report highlights the importance of studying HIV controllers in high incidence settings.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/etiologia , HIV-1/fisiologia , Adulto , Feminino , Infecções por HIV/virologia , HIV-1/genética , Antígenos HLA-B/genética , Cadeias HLA-DRB1/genética , Humanos , África do Sul , Carga Viral , Replicação Viral
9.
J Obstet Gynaecol ; 37(1): 48-52, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27690695

RESUMO

Leptin, primarily produced by adipocytes, is implicated in the development of pre-eclampsia. This study examines placental leptin production and serum leptin levels in HIV infected and uninfected normotensive and pre-eclamptic pregnancies. Placental leptin production was analysed by RT-PCR and serum leptin levels by ELISA in normotensive (n = 90) and pre-eclamptic (n = 90) pregnancies which were further stratified by HIV status. Placental leptin production was higher in pre-eclampsia compared to normotensive pregnancies irrespective of HIV status (p = .04). Serum leptin was non-significantly raised in HIV uninfected (p = .42) but lower in HIV-infected (p = .03) pre-eclampsia. The latter had lower BMI (p = .007) and triceps skin-fold thickness (p < .001) than the HIV uninfected groups with a significant correlation between serum leptin and triceps skin-fold thickness (p < .001), indicative of less adipose tissue in HIV-infected women with consequently lower serum leptin. Thus, serum leptin levels are not indicative of increased placental production when pre-eclampsia is associated with HIV infection.


Assuntos
Infecções por HIV/metabolismo , Leptina/sangue , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Complicações Infecciosas na Gravidez/metabolismo , RNA Mensageiro/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Infecções por HIV/sangue , Infecções por HIV/complicações , Humanos , Leptina/genética , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/virologia , Gravidez , Complicações Infecciosas na Gravidez/sangue , Complicações Infecciosas na Gravidez/virologia
10.
J Infect Dis ; 212(11): 1827-34, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26014799

RESUMO

Improved biomarkers are needed for tuberculosis. To develop tests based on products secreted by tubercle bacilli that are strictly associated with viability, we evaluated 3 bacterial-derived, species-specific, small molecules as biomarkers: 2 mycobactin siderophores and tuberculosinyladenosine. Using liquid chromatography-tandem mass spectrometry, we demonstrated the presence of 1 or both mycobactins and/or tuberculosinyladenosine in serum and whole lung tissues from infected mice and sputum, cerebrospinal fluid (CSF), or lymph nodes from infected patients but not uninfected controls. Detection of the target molecules distinguished host infection status in 100% of mice with both serum and lung as the target sample. In human subjects, we evaluated detection of the bacterial small molecules (BSMs) in multiple body compartments in 3 patient cohorts corresponding to different forms of tuberculosis. We detected at least 1 of the 3 molecules in 90%, 71%, and 40% of tuberculosis patients' sputum, CSF, and lymph node samples, respectively. In paucibacillary forms of human tuberculosis, which are difficult to diagnose even with culture, detection of 1 or more BSM was rapid and compared favorably to polymerase chain reaction-based detection. Secreted BSMs, detectable in serum, warrant further investigation as a means for diagnosis and therapeutic monitoring in patients with tuberculosis.


Assuntos
Biomarcadores/análise , Mycobacterium tuberculosis/química , Oxazóis/análise , Tuberculose/diagnóstico , Adenosina/análogos & derivados , Adenosina/análise , Animais , Técnicas de Tipagem Bacteriana , Cromatografia Líquida , Humanos , Pulmão/microbiologia , Camundongos , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Espectrometria de Massas em Tandem
11.
J Virol ; 88(8): 4291-303, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24478420

RESUMO

UNLABELLED: The antiviral role of TRIM E3 ligases in vivo is not fully understood. To test the hypothesis that TRIM5α and TRIM22 have differential transcriptional regulation and distinct anti-HIV roles according to infection phase and compartment, we measured TRIM5α, TRIM22, and type I interferon (IFN-I)-inducible myxovirus resistance protein A (MxA) levels in peripheral blood mononuclear cells (PBMCs) during primary and chronic HIV-1 infection, with chronic infection samples being matched PBMCs and central nervous system (CNS)-derived cells. Associations with biomarkers of disease progression were explored. The impact of IFN-I, select proinflammatory cytokines, and HIV on TRIM E3 ligase-specific expression was investigated. PBMCs from individuals with primary and chronic HIV-1 infection had significantly higher levels of MxA and TRIM22 than did PBMCs from HIV-1-negative individuals (P < 0.05 for all comparisons). PBMCs from chronic infection had lower levels of TRIM5α than did PBMCs from primary infection or HIV-1-uninfected PBMCs (P = 0.0001 for both). In matched CNS-derived samples and PBMCs, higher levels of MxA (P = 0.001) and TRIM5α (P = 0.0001) in the CNS were noted. There was a negative correlation between TRIM22 levels in PBMCs and plasma viral load (r = -0.40; P = 0.04). In vitro, IFN-I and, rarely, proinflammatory cytokines induced TRIM5α and TRIM22 in a cell type-dependent manner, and the knockdown of either protein in CD4(+) lymphocytes resulted in increased HIV-1 infection. These data suggest that there are infection-phase-specific and anatomically compartmentalized differences in TRIM5α and TRIM22 regulation involving primarily IFN-I and specific cell types and indicate subtle differences in the antiviral roles and transcriptional regulation of TRIM E3 ligases in vivo. IMPORTANCE: Type I interferon-inducible TRIM E3 ligases are a family of intracellular proteins with potent antiviral activities mediated through diverse mechanisms. However, little is known about the contribution of these proteins to antiviral immunity in vivo and how their expression is regulated. We show here that TRIM5α and TRIM22, two prominent members of the family, have different expression patterns in vivo and that the expression pattern depends on HIV-1 infection status and phase. Furthermore, expression differs in peripheral blood versus central nervous system anatomical sites of infection. Only TRIM22 expression correlated negatively with HIV-1 viral load, but gene silencing of both proteins enhances HIV-1 infection of target cells. We report subtle differences in TRIM5α and TRIM22 gene induction by IFN-I and proinflammatory cytokines in CD4(+) lymphocytes, monocytes, and neuronal cells. This study enhances our understanding of antiviral immunity by intrinsic antiviral factors and how their expression is determined.


Assuntos
Proteínas de Transporte/metabolismo , Infecções por HIV/metabolismo , HIV-1/fisiologia , Proteínas Repressoras/metabolismo , Adolescente , Adulto , Fatores de Restrição Antivirais , Proteínas de Transporte/genética , Criança , Estudos de Coortes , Feminino , Regulação da Expressão Gênica , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/genética , Humanos , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Antígenos de Histocompatibilidade Menor , Proteínas de Resistência a Myxovirus/genética , Proteínas de Resistência a Myxovirus/metabolismo , Proteínas Repressoras/genética , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases , Replicação Viral , Adulto Jovem
12.
J Clin Microbiol ; 52(10): 3777-80, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25056328

RESUMO

There are no data about the comparative accuracy of commercially available nucleic acid amplification tests (GeneXpert MTB/RIF and Roche Amplicor) for the diagnosis of tuberculous meningitis (TBM). A total of 148 patients with suspected TBM were evaluated, and cultures served as the reference standard. The sensitivities and specificities (95% confidence interval [CI]) for the Amplicor and Xpert MTB/RIF tests were similar: 46 (31-60) versus 50 (33-67) and 99 (93-100) and 94 (84-99), respectively.


Assuntos
Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Tuberculose Meníngea/diagnóstico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
13.
J Infect Dev Ctries ; 18(2): 258-265, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38484352

RESUMO

INTRODUCTION: Mycoplasma hominis and Ureaplasma parvum have been recently linked to sexually transmitted diseases and other conditions. There are a limited number of studies conducted on South African pregnant women that have assessed the prevalence and risk factors for genital mycoplasmas. METHODOLOGY: This study included 264 HIV infected pregnant women attending the King Edward VIII antenatal clinic in eThekwini, South Africa. DNA was extracted using the PureLink Microbiome kit and pathogens were detected using the TaqMan Real-time PCR assays. The statistical data analysis was conducted in a freely available Statistical Computing Environment, R software, version 3.6.3 using the RStudio platform. RESULTS: The prevalence of M. hominis and U. parvum, was 215/264 (81.4%), and 203/264 (76.9%), respectively. In the M. hominis positive group, a significantly (p = 0.004) higher proportion, 80.5% tested positive for U. parvum infection when compared to 61.2% among the M. hominis negative. Of the U. parvum positive women, a significantly (p = 0.004) higher proportion of women (85.2%) tested positive for M. hominis when compared to 68.9% among the U. parvum negative. In the unadjusted and adjusted analysis, being M. hominis positive increased the risk for U. parvum by approximately 3 times more (p = 0.014) and 4-fold (p = 0.008), respectively. CONCLUSIONS: This study showed a significant link between M. hominis and U. parvum infection. To date, there are a limited number of studies that have investigated M. hominisbeing a risk factor for U. parvum infection. Therefore, the data presented in the current study now fills in this gap in the literature.


Assuntos
Infecções por Mycoplasma , Infecções por Ureaplasma , Humanos , Feminino , Gravidez , Mycoplasma hominis , Gestantes , HIV , Infecções por Mycoplasma/epidemiologia , Ureaplasma/genética , Infecções por Ureaplasma/epidemiologia , Ureaplasma urealyticum/genética
14.
PLoS Med ; 10(10): e1001536, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24167451

RESUMO

BACKGROUND: Tuberculous meningitis (TBM) is difficult to diagnose promptly. The utility of the Xpert MTB/RIF test for the diagnosis of TBM remains unclear, and the effect of host- and sample-related factors on test performance is unknown. This study sought to evaluate the sensitivity and specificity of Xpert MTB/RIF for the diagnosis of TBM. METHODS AND FINDINGS: 235 South-African patients with a meningeal-like illness were categorised as having definite (culture or Amplicor PCR positive), probable (anti-TBM treatment initiated but microbiological confirmation lacking), or non-TBM. Xpert MTB/RIF accuracy was evaluated using 1 ml of uncentrifuged and, when available, 3 ml of centrifuged cerebrospinal fluid (CSF). To evaluate the incremental value of MTB/RIF over a clinically based diagnosis, test accuracy was compared to a clinical score (CS) derived using basic clinical and laboratory information. Of 204 evaluable patients (of whom 87% were HIV-infected), 59 had definite TBM, 64 probable TBM, and 81 non-TBM. Overall sensitivity and specificity (95% CI) were 62% (48%-75%) and 95% (87%-99%), respectively. The sensitivity of Xpert MTB/RIF was significantly better than that of smear microscopy (62% versus 12%; p = 0.001) and significantly better than that of the CS (62% versus 30%; p = 0.001; C statistic 85% [79%-92%]). Xpert MTB/RIF sensitivity was higher when centrifuged versus uncentrifuged samples were used (82% [62%-94%] versus 47% [31%-61%]; p = 0.004). The combination of CS and Xpert MTB/RIF (Xpert MTB/RIF performed if CS<8) performed as well as Xpert MTB/RIF alone but with a ∼10% reduction in test usage. This overall pattern of results remained unchanged when the definite and probable TBM groups were combined. Xpert MTB/RIF was not useful in identifying TBM among HIV-uninfected individuals, although the sample was small. There was no evidence of PCR inhibition, and the limit of detection was ∼80 colony forming units per millilitre. Study limitations included a predominantly HIV-infected cohort and the limited number of culture-positive CSF samples. CONCLUSIONS: Xpert MTB/RIF may be a good rule-in test for the diagnosis of TBM in HIV-infected individuals from a tuberculosis-endemic setting, particularly when a centrifuged CSF pellet is used. Further studies are required to confirm these findings in different settings. Please see later in the article for the Editors' Summary.


Assuntos
Reação em Cadeia da Polimerase/métodos , Tuberculose Meníngea/diagnóstico , Adulto , Feminino , Humanos , Masculino , Estudos Prospectivos , Tuberculose Meníngea/genética , Adulto Jovem
15.
S Afr J Infect Dis ; 38(1): 466, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36756244

RESUMO

Background: Helminth and HIV infections are endemic among poor populations. Studies investigating the socio-demographic and economic risk factors associated with dual HIV and helminth coinfection are scarce. Objectives: This study aimed to describe risk factors associated with HIV and helminth coinfections among peri-urban South African adults residing in poorly developed areas with high poverty levels, lack of sanitation and a clean water supply. Method: Adult participants (n = 414) were recruited from clinics in the south of Durban, KwaZulu-Natal, South Africa. Participants' demographic, socio-economic, sanitation and household information, anthropometric measurements and HIV status were collected. Stool samples were donated for coproscopy to detect helminths using the Kato-Katz and Mini Parasep techniques. Blood was collected to confirm participants' HIV status and to determine Ascaris lumbricoides-specific immunoglobulin E (IgE) and immunoglobulin G4 (IgG4) levels to improve microscopy sensitivity. Results: Overall coinfection was 15%, and single helminth and HIV prevalence were 33% and 52%, respectively. Ascaris lumbricoides was predominant (18%). Univariate analysis of variance (ANOVA) showed that coinfection was 11.9% and 19.8%, respectively, among the 18-34 years and 35-59 years age groups (p = 0.0006), 16.4% and 19.9%, respectively, for the no income and < R1000.00 groups (p = 0.0358) and 22.8% and 17.1%, respectively, for the pit or public toilets and toilets not connected to sewage groups (p = 0.0007). Conclusion: Findings suggest that the dual infection with HIV and helminth infections among adults residing in under-resourced areas with poor sanitary conditions is frequent. Older age, poor toilet use and low income are associated with coinfection. More attention is required to break the cycle of coinfections and possible disease interactions. Contribution: The study highlights the importance of determining and treating helminth infections among adult population during HIV and helminth coinfection and the influence of poor sanitation and socioeconomic status on disease transmission.

16.
Afr J Lab Med ; 12(1): 1975, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36873290

RESUMO

Background: Rifampicin resistance missed by commercial rapid molecular assays but detected by phenotypic assays may lead to discordant susceptibility results and affect patient management. Objective: This study was conducted to evaluate the causes of rifampicin resistance missed by the GenoType MTBDRplus and its impact on the programmatic management of tuberculosis in KwaZulu-Natal, South Africa. Methods: We analysed routine tuberculosis programme data from January 2014 to December 2014 on isolates showing rifampicin susceptibility on the GenoType MTBDRplus assay but resistance on the phenotypic agar proportion method. Whole-genome sequencing was performed on a subset of these isolates. Results: Out of 505 patients with isoniazid mono-resistant tuberculosis on the MTBDRplus, 145 (28.7%) isolates showed both isoniazid and rifampicin resistance on the phenotypic assay. The mean time from MTBDRplus results to initiation of drug-resistant tuberculosis therapy was 93.7 days. 65.7% of the patients had received previous tuberculosis treatment. The most common mutations detected in the 36 sequenced isolates were I491F (16; 44.4%) and L452P (12; 33.3%). Among the 36 isolates, resistance to other anti-tuberculosis drugs was 69.4% for pyrazinamide, 83.3% for ethambutol, 69.4% for streptomycin, and 50% for ethionamide. Conclusion: Missed rifampicin resistance was mostly due to the I491F mutation located outside the MTBDRplus detection area and the L452P mutation, which was not included in the initial version 2 of the MTBDRplus. This led to substantial delays in the initiation of appropriate therapy. The previous tuberculosis treatment history and the high level of resistance to other anti-tuberculosis drugs suggest an accumulation of resistance.

17.
Microorganisms ; 11(7)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37513018

RESUMO

BACKGROUND: Helminth infections are widespread in tuberculosis-endemic areas and are associated with an increased risk of active tuberculosis. In contrast to the pro-inflammatory Th1 responses elicited by Mycobacterium tuberculosis (Mtb) infection, helminth infections induce anti-inflammatory Th2/Treg responses. A robust Th2 response has been linked to reduced tuberculosis protection. Several studies show the effect of helminth infection on BCG vaccination and TB, but the mechanisms remain unclear. AIM: To determine the cytokine response profiles during tuberculosis and intestinal helminth coinfection. METHODS: For the in vitro study, lymphocytic Jurkat and monocytic THP-1 cell lines were stimulated with Mtb H37Rv and Ascaris lumbricoides (A. lumbricoides) excretory-secretory protein extracts for 24 and 48 h. The pilot human ex vivo study consisted of participants infected with Mtb, helminths, or coinfected with both Mtb and helminths. Thereafter, the gene transcription levels of IFN-γ, TNF-α, granzyme B, perforin, IL-2, IL-17, NFATC2, Eomesodermin, IL-4, IL-5, IL-10, TGF-ß and FoxP3 in the unstimulated/uninfected controls, singly stimulated/infected and costimulated/coinfected groups were determined using RT-qPCR. RESULTS: TB-stimulated Jurkat cells had significantly higher levels of IFN-γ, TNF-α, granzyme B, and perforin compared to unstimulated controls, LPS- and A. lumbricoides-stimulated cells, and A. lumbricoides plus TB-costimulated cells (p < 0.0001). IL-2, IL-17, Eomes, and NFATC2 levels were also higher in TB-stimulated Jurkat cells (p < 0.0001). Jurkat and THP-1 cells singly stimulated with TB had lower IL-5 and IL-4 levels compared to those singly stimulated with A. lumbricoides and those costimulated with TB plus A. lumbricoides (p < 0.0001). A. lumbricoides-singly stimulated cells had higher IL-4 levels compared to TB plus A. lumbricoides-costimulated Jurkat and THP-1 cells (p < 0.0001). TGF-ß levels were also lower in TB-singly stimulated cells compared to TB plus A. lumbricoides-costimulated cells (p < 0.0001). IL-10 levels were lower in TB-stimulated Jurkat and THP-1 cells compared to TB plus A. lumbricoides-costimulated cells (p < 0.0001). Similar results were noted for the human ex vivo study, albeit with a smaller sample size. CONCLUSIONS: Data suggest that helminths induce a predominant Th2/Treg response which may downregulate critical Th1 responses that are crucial for tuberculosis protection.

18.
Diagnostics (Basel) ; 13(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37568838

RESUMO

BACKGROUND: Intestinal helminth parasites are potent stimulators of T helper type 2 (Th2) and regulatory Th3 anti-inflammatory immune responses, while human immunodeficiency virus (HIV) infections are activators of predominantly T helper type 1(Th1) pro-inflammatory responses. Studies investigating the immune profiles of individuals coinfected with helminths and HIV are scarce. Although it is well known that helminths cause a type 2 immune response during the chronic stage of infection that is characterised by Th2 cell differentiation, eosinophil recruitment, and alternative macrophage activation, the immune mechanisms that regulate tissue damage at the time of parasite invasion are poorly understood. AIM: The aim of the study was to determine the cytokine gene expression profiles during HIV and helminth coinfection in underprivileged South African adults living in a peri-urban area with poor sanitary conditions and a lack of clean water supply. METHOD: Study participants (n = 164) were subdivided into uninfected controls, HIV-infected, helminth-infected, and HIV and helminth-coinfected groups. The Kato-Katz and Mini Parasep techniques and Ascaris lumbricoides-specific Immunoglobulin E (IgE) and Immunoglobulin G4 (IgG4) levels were used to detect helminth infections. Participants' HIV status was determined using two HIV1/2 antibody test kits. RNA was isolated from white blood cells for cytokine (Th1-, Th2-, and Th17-related) and transcription factor gene expression profiling using real-time PCR. RESULTS: Multivariate regression data were adjusted for age, gender, BMI, antiretroviral treatment (ART), and nutritional supplement intake. The HIV and helminth-coinfected group had significantly higher tumour necrosis factor alpha (TNF-α) (adjusted ß = 0.53, p = 0.036), interleukin 2 (IL-2) (adjusted ß = 6.48, p = 0.008), and interleukin 17 (IL-17) (adjusted ß = 1.16, p = 0.001) levels and lower GATA binding protein 3 (GATA3) levels (adjusted ß = -0.77, p = 0.018) compared to the uninfected controls. No statistical significance was noted for Th2-related cytokines. CONCLUSION: The coinfected group had higher proinflammatory Th1- and Th17-related cytokine gene expression profiles compared to the uninfected controls. The findings suggest that pro-inflammatory responses are elevated during coinfection, which supports the hypothesis that helminths have a deleterious effect on HIV immune responses.

19.
J Med Microbiol ; 72(11)2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37929930

RESUMO

Introduction. Intestinal helminths and microbiota share the same anatomical niche during infection and are likely to interact either directly or indirectly. Whether intestinal helminths employ bactericidal strategies that influence their microbial environment is not completely understood.Hypothesis. In the present study, the hypothesis that the adult hookworm Nippostrongylus brasiliensis produces molecules that impair bacterial growth in vitro, is tested.Aim. To investigate the in vitro bactericidal activity of Nippostrongylus brasiliensis against commensal and pathogenic bacteria.Methodology. The bactericidal effect of somatic extract and excretory-secretory products of adult Nippostrongylus brasiliensis on Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli, Salmonella enterica serovar Typhimurium, and Klebsiella pneumoniae) bacteria was assessed using growth assays. Minimum inhibitory concentration and minimum bactericidal concentration assays were performed using excretory-secretory products released from the pathogen.Results. Broad-spectrum in vitro bactericidal activity in excretory-secretory products, but not somatic extract of adult Nippostrongylus brasiliensis was detected. The bactericidal activity of excretory-secretory products was concentration-dependent, maintained after heat treatment, and preserved after repeated freezing and thawing.Conclusion. The results of this study demonstrate that helminths such as Nippostrongylus brasiliensis release molecules via their excretory-secretory pathway that have broad-spectrum bactericidal activity. The mechanisms responsible for this bactericidal activity remain to be determined and further studies aimed at isolating and identifying active bactericidal molecules are needed.


Assuntos
Enteropatias Parasitárias , Nippostrongylus , Animais
20.
J Virol ; 85(1): 208-16, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20980524

RESUMO

Type 1 interferons (IFNs) induce the expression of the tripartite interaction motif (TRIM) family of E3 ligases, but the contribution of these antiviral factors to HIV pathogenesis is not completely understood. We hypothesized that the increased expression of select type 1 IFN and TRIM isoforms is associated with a significantly lower likelihood of HIV-1 acquisition and viral control during primary HIV-1 infection. We measured IFN-α, IFN-ß, myxovirus resistance protein A (MxA), human TRIM5α (huTRIM5α), and TRIM22 mRNA levels in peripheral blood mononuclear cells (PBMCs) of high-risk, HIV-1-uninfected participants and HIV-1-positive study participants. Samples were available for 32 uninfected subjects and 28 infected persons, all within 1 year of infection. HIV-1-positive participants had higher levels of IFN-ß (P = 0.0005), MxA (P = 0.007), and TRIM22 (P = 0.01) and lower levels of huTRIM5α (P < 0.001) than did HIV-1-negative participants. TRIM22 but not huTRIM5α correlated positively with type 1 IFN (IFN-α, IFN-ß, and MxA) (all P < 0.0001). In a multivariate model, increased MxA expression showed a significant positive association with viral load (P = 0.0418). Furthermore, TRIM22 but not huTRIM5α, IFN-α, IFN-ß, or MxA showed a negative correlation with plasma viral load (P = 0.0307) and a positive correlation with CD4(+) T-cell counts (P = 0.0281). In vitro studies revealed that HIV infection induced TRIM22 expression in PBMCs obtained from HIV-negative donors. Stable TRIM22 knockdown resulted in increased HIV-1 particle release and replication in Jurkat reporter cells. Collectively, these data suggest concordance between type 1 IFN and TRIM22 but not huTRIM5α expression in PBMCs and that TRIM22 likely acts as an antiviral effector in vivo.


Assuntos
Antivirais/farmacologia , Infecções por HIV/imunologia , HIV-1/efeitos dos fármacos , Interferon-alfa/farmacologia , Interferon beta/farmacologia , Proteínas Repressoras/farmacologia , Antivirais/metabolismo , Linhagem Celular , Estudos de Coortes , Feminino , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/farmacologia , Infecções por HIV/virologia , HIV-1/imunologia , Humanos , Interferon-alfa/genética , Interferon-alfa/metabolismo , Interferon beta/genética , Interferon beta/metabolismo , Células Jurkat , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Ativação Linfocitária , Antígenos de Histocompatibilidade Menor , Proteínas de Resistência a Myxovirus , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteínas com Motivo Tripartido
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