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1.
Open Forum Infect Dis ; 11(3): ofae021, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38510916

ABSTRACT

Background: Tuberculous pericarditis (TBP) is a paucibacillary disease, where host biomarkers such as unstimulated interferon γ (IRISA-TB) have high diagnostic accuracy. However, DNA-based diagnostic tests (GeneXpert Ultra), more sensitive than an earlier versions, have recently become available. Given that the diagnosis of TBP is challenging, we performed a comparative diagnostic accuracy study comparing both assays. Methods: We recruited 99 consecutive patients with suspected TBP in Cape Town, South Africa. Definite TBP was defined by microbiological confirmation of tuberculosis (TB) on pericardial fluid culture or an alternative polymerase chain reaction-based test (GeneXpert MTB/RIF) or by use of sputum (polymerase chain reaction or culture). Probable TBP was defined as a high clinical suspicion of TB accompanied by anti-TB treatment, while non-TBP was defined as negative microbiological test results for TB without initiation of TB treatment and/or the presence of an alternative diagnosis. Results: There were 39 patients with definite TBP, 35 with probable TBP, and 23 with non-TBP. Approximately 70% of participants who received TB treatment were HIV coinfected. Overall, IRISA-TB was more sensitive than Xpert Ultra (88.6% [95% CI, 74.1%-95.5%] vs 71.5% [55.0%-83.7%], n = 53) and significantly more sensitive in participants who were HIV uninfected (100% [95% CI, 72.3%-100.0%] vs 60% [31.3%-83.2%], P = .03). In patients with definite and probable TBP combined (n = 84), sensitivity was significantly higher with IRISA-TB (77.3% [95% CI, 65.9%-85.8%] vs 37.9 [27.2%-50.0%], P < .0001). A similar pattern was seen in persons who were HIV uninfected (88.3% vs 35.3%, P = .002). Specificity was high for both assays (>95%). Conclusions: Unstimulated interferon γ (IRISA-TB) was significantly more sensitive than Xpert Ultra for the diagnosis of TB pericarditis in a TB-endemic resource-poor setting.

2.
Am J Respir Crit Care Med ; 209(7): 840-851, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38226855

ABSTRACT

Rationale: In the upper respiratory tract, replicating (culturable) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is recoverable for ∼4-8 days after symptom onset, but there is a paucity of data about the frequency and duration of replicating virus in the lower respiratory tract (i.e., the human lung).Objectives: We undertook lung tissue sampling (needle biopsy) shortly after death in 42 mechanically ventilated decedents during the Beta and Delta waves. An independent group of 18 ambulatory patients served as a control group.Methods: Lung biopsy cores from decedents underwent viral culture, histopathological analysis, electron microscopy, transcriptomic profiling, and immunohistochemistry.Measurements and Main Results: Thirty-eight percent (16 of 42) of mechanically ventilated decedents had culturable virus in the lung for a median of 15 days (persisting for up to 4 wk) after symptom onset. Lung viral culture positivity was not associated with comorbidities or steroid use. Delta but not Beta variant lung culture positivity was associated with accelerated death and secondary bacterial infection (P < 0.05). Nasopharyngeal culture was negative in 23.1% (6 of 26) of decedents despite lung culture positivity. This hitherto undescribed biophenotype of lung-specific persisting viral replication was associated with an enhanced transcriptomic pulmonary proinflammatory response but with concurrent viral culture positivity.Conclusions: Concurrent rather than sequential active viral replication continues to drive a heightened proinflammatory response in the human lung beyond the second week of illness and was associated with variant-specific increased mortality and morbidity. These findings have potential implications for the design of interventional strategies and clinical management of patients with severe coronavirus disease (COVID-19).


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Lung , COVID-19 Testing , Virus Replication
3.
Infect Drug Resist ; 16: 5427-5432, 2023.
Article in English | MEDLINE | ID: mdl-37638062

ABSTRACT

Purpose: Carbapenem-resistant bacteria (CRB) pose a major health risk to patients in intensive care units (ICU) across African hospitals. There are hardly any data about the role of hospital sinks as reservoirs of CRB in resource-poor African settings. Furthermore, the specific within-sink location of the highest concentration of pathogens and the role of splash back as a transmission mechanism remains poorly clarified. Methods: We swabbed ICU sluice room sinks in a tertiary hospital in Cape Town, South Africa. Swabs were taken from four different parts of the sluice room sinks (tap-opening, trap, below the trap, and u-bend). Dilutions were prepared and plated on carbapenem-infused agar. Colonies were identified and drug resistance profiles were determined using a biochemical analyser. To evaluate the potential transmission from the sink, similar plates were placed at fixed distances from the sink when the tap was turned on and off. Results: CRB were isolated from the trap, water interface below the trap, and the u-bend (the latter harboured the highest density of CRB species). Five CRB, resistant to at least 7 antibiotic classes, were isolated including Pseudomonas, Klebsiella, Citrobacter, Serratia, and Providencia. CRB could be cultured from droplets that fell on agar-containing plates placed at a varying distance from the trap. Conclusion: There is a higher density of CRB in the u-bend of ICU sluice room sinks which can act as a potential source of transmission. The data inform targeted CRB transmission-interruption strategies in resource-poor settings.

4.
Nat Med ; 29(4): 1009-1016, 2023 04.
Article in English | MEDLINE | ID: mdl-36894651

ABSTRACT

Two in every five patients with active tuberculosis (TB) remain undiagnosed or unreported. Therefore community-based, active case-finding strategies require urgent implementation. However, whether point-of-care (POC), portable battery-operated, molecular diagnostic tools deployed at a community level, compared with conventionally used POC smear microscopy, can shorten time-to-treatment initiation, thus potentially curtailing transmission, remains unclear. To clarify this issue, we performed an open-label, randomized controlled trial in periurban informal settlements of Cape Town, South Africa, where we TB symptom screened 5,274 individuals using a community-based scalable mobile clinic. Some 584 individuals with HIV infection or symptoms of TB underwent targeted diagnostic screening and were randomized (1:1) to same-day smear microscopy (n = 296) or on-site DNA-based molecular diagnosis (n = 288; GeneXpert). The primary aim was to compare time to TB treatment initiation between the arms. Secondary aims included feasibility and detection of probably infectious people. Of participants who underwent targeted screening, 9.9% (58 of 584) had culture-confirmed TB. Time-to-treatment initiation occurred significantly earlier in the Xpert versus the smear-microscopy arm (8 versus 41 d, P = 0.002). However, overall, Xpert detected only 52% of individuals with culture-positive TB. Notably, Xpert detected almost all of the probably infectious patients compared with smear microscopy (94.1% versus 23.5%, P = <0.001). Xpert was associated with a shorter median time to treatment of probably infectious patients (7 versus 24 d, P = 0.02) and a greater proportion of infectious patients were on treatment at 60 d compared with the probably noninfectious patients (76.5% versus 38.2%, P < 0.01). Overall, a greater proportion of POC Xpert-positive participants were on treatment at 60 d compared with all culture-positive participants (100% versus 46.5%, P < 0.01). These findings challenge the traditional paradigm of a passive case-finding, public health strategy and argues for the implementation of portable DNA-based diagnosis with linkage to care as a community-oriented, transmission-interruption strategy. The study was registered with the South African National Clinical Trials Registry (application ID 4367; DOH-27-0317-5367) and ClinicalTrials.gov (NCT03168945).


Subject(s)
HIV Infections , Mycobacterium tuberculosis , Tuberculosis , Humans , HIV Infections/diagnosis , HIV Infections/complications , Mycobacterium tuberculosis/genetics , South Africa/epidemiology , Sputum , Tuberculosis/diagnosis , Tuberculosis/drug therapy
5.
Am J Reprod Immunol ; 88(6): e13643, 2022 12.
Article in English | MEDLINE | ID: mdl-36302121

ABSTRACT

PROBLEM: Both luteal phase progesterone (P4) levels and use of the intramuscular (IM) injectable progestin-only contraceptive depo-medroxyprogesterone acetate (DMPA-IM) have been linked to increased S/HIV acquisition in animal, clinical and in vitro models. Several plausible mechanisms could explain MPA-induced HIV-1 acquisition while those for the luteal phase are underexplored. METHOD OF STUDY: Peripheral blood mononuclear cells (PBMCs) were treated with P4 and estrogen at concentrations mimicking the luteal phase, follicular phase or with levels of MPA mimicking peak serum levels in DMPA-IM users. Cells were infected with an R5-tropic infectious molecular clone and HIV-1 infection was measured. A role for the glucocorticoid receptor (GR) was investigated using the GR/PR antagonist RU486. CCR5 protein levels and activation status, assessed by levels of the activation marker CD69, were measured by flow cytometry after treatment in vitro and in PBMCs from naturally-cycling women or DMPA-IM users. RESULTS: Both MPA and luteal phase hormones significantly increased HIV-1 infection in vitro. However, MPA but not luteal phase hormones increased the CD4+/CD8+ T cell ratio, CCR5 protein expression on CD4+ T cells and increased expression of the activation marker CD69. The GR is involved in MPA-induced, but not luteal phase hormone-induced increased HIV-1 infection. In DMPA-IM users, the frequency of CCR5-expressing CD3+ and CD8+ cells was higher than for women in the luteal phase. CONCLUSIONS: MPA increases HIV-1 infection in a manner different from that of luteal phase hormones, most likely involving the GR and at least in part changes in the frequency and/or expression of CCR5 and CD69.


Subject(s)
Contraceptive Agents, Female , HIV Infections , HIV-1 , Female , Humans , Contraceptive Agents, Female/pharmacology , HIV Infections/drug therapy , HIV-1/physiology , Leukocytes, Mononuclear/metabolism , Medroxyprogesterone Acetate/pharmacology , Menstrual Cycle , Progesterone , Receptors, Glucocorticoid/metabolism
6.
J Immunol ; 209(9): 1746-1759, 2022 11 01.
Article in English | MEDLINE | ID: mdl-36162872

ABSTRACT

α1-Antitrypsin (AAT), a serine protease inhibitor, is the third most abundant protein in plasma. Although the best-known function of AAT is irreversible inhibition of elastase, AAT is an acute-phase reactant and is increasingly recognized to have a panoply of other functions, including as an anti-inflammatory mediator and a host-protective molecule against various pathogens. Although a canonical receptor for AAT has not been identified, AAT can be internalized into the cytoplasm and is known to affect gene regulation. Because AAT has anti-inflammatory properties, we examined whether AAT binds the cytoplasmic glucocorticoid receptor (GR) in human macrophages. We report the finding that AAT binds to GR using several approaches, including coimmunoprecipitation, mass spectrometry, and microscale thermophoresis. We also performed in silico molecular modeling and found that binding between AAT and GR has a plausible stereochemical basis. The significance of this interaction in macrophages is evinced by AAT inhibition of LPS-induced NF-κB activation and IL-8 production as well as AAT induction of angiopoietin-like 4 protein, which are, in part, dependent on GR. Furthermore, this AAT-GR interaction contributes to a host-protective role against mycobacteria in macrophages. In summary, this study identifies a new mechanism for the gene regulation, anti-inflammatory, and host-defense properties of AAT.


Subject(s)
Receptors, Glucocorticoid , alpha 1-Antitrypsin , Humans , alpha 1-Antitrypsin/metabolism , alpha 1-Antitrypsin Deficiency , Angiopoietins/metabolism , Angiopoietins/therapeutic use , Anti-Inflammatory Agents/therapeutic use , Interleukin-8/metabolism , Lipopolysaccharides/pharmacology , Macrophages/metabolism , NF-kappa B/metabolism , Pancreatic Elastase/metabolism , Receptors, Glucocorticoid/metabolism , Serine Proteinase Inhibitors
7.
Am J Respir Crit Care Med ; 205(10): 1214-1227, 2022 05 15.
Article in English | MEDLINE | ID: mdl-35175905

ABSTRACT

Rationale: Improving treatment outcomes while reducing drug toxicity and shortening the treatment duration to ∼6 months remains an aspirational goal for the treatment of multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB). Objectives: To conduct a multicenter randomized controlled trial in adults with MDR/RR-TB (i.e., without resistance to fluoroquinolones or aminoglycosides). Methods: Participants were randomly assigned (1:1 ratio) to a ∼6-month all-oral regimen that included levofloxacin, bedaquiline, and linezolid, or the standard-of-care (SOC) ⩾9-month World Health Organization (WHO)-approved injectable-based regimen. The primary endpoint was a favorable WHO-defined treatment outcome (which mandates that prespecified drug substitution is counted as an unfavorable outcome) 24 months after treatment initiation. The trial was stopped prematurely when bedaquiline-based therapy became the standard of care in South Africa. Measurements and Main Results: In total, 93 of 111 randomized participants (44 in the comparator arm and 49 in the interventional arm) were included in the modified intention-to-treat analysis; 51 (55%) were HIV coinfected (median CD4 count, 158 cells/ml). Participants in the intervention arm were 2.2 times more likely to experience a favorable 24-month outcome than participants in the SOC arm (51% [25 of 49] vs. 22.7% [10 of 44]; risk ratio, 2.2 [1.2-4.1]; P = 0.006). Toxicity-related drug substitution occurred more frequently in the SOC arm (65.9% [29 of 44] vs. 34.7% [17 of 49]; P = 0.001)], 82.8% (24 of 29) owing to kanamycin (mainly hearing loss; replaced by bedaquiline) in the SOC arm, and 64.7% (11 of 17) owing to linezolid (mainly anemia) in the interventional arm. Adverse event-related treatment discontinuation in the safety population was more common in the SOC arm (56.4% [31 of 55] vs. 32.1% [17 of 56]; P = 0.007). However, grade 3 adverse events were more common in the interventional arm (55.4% [31 of 56] vs. 32.7 [18 of 55]; P = 0.022). Culture conversion was significantly better in the intervention arm (hazard ratio, 2.6 [1.4-4.9]; P = 0.003) after censoring those with bedaquiline replacement in the SOC arm (and this pattern remained consistent after censoring for drug replacement in both arms; P = 0.01). Conclusions: Compared with traditional injectable-containing regimens, an all-oral 6-month levofloxacin, bedaquiline, and linezolid-containing MDR/RR-TB regimen was associated with a significantly improved 24-month WHO-defined treatment outcome (predominantly owing to toxicity-related drug substitution). However, drug toxicity occurred frequently in both arms. These findings inform strategies to develop future regimens for MDR/RR-TB.Clinical trial registered with www.clinicaltrials.gov (NCT02454205).


Subject(s)
Drug-Related Side Effects and Adverse Reactions , Tuberculosis, Multidrug-Resistant , Adult , Antitubercular Agents/adverse effects , Diarylquinolines/therapeutic use , Drug-Related Side Effects and Adverse Reactions/drug therapy , Humans , Levofloxacin/therapeutic use , Linezolid/therapeutic use , Rifampin/therapeutic use , Tuberculosis, Multidrug-Resistant/drug therapy
8.
Front Immunol ; 12: 676679, 2021.
Article in English | MEDLINE | ID: mdl-34149712

ABSTRACT

Introduction: Protective host responses in those exposed to or infected with tuberculosis (TB) is thought to require a delicate balance between pro-inflammatory and regulatory immune responses. Myeloid-derived suppressor cells (MDSCs), regulatory cells that dampen T-cell function, have been described in cancer and other infectious diseases but there are limited data on their role in TB. Methods: Peripheral blood was obtained from patients with active pulmonary TB and participants with presumed latent TB infection (LTBI) from Cape Town, South Africa. MDSC frequency was ascertained by flow cytometry. Purified MDSCs were used to assess (i) their suppressive effect on T-cell proliferation using a Ki67 flow cytometric assay and (ii) their effect on mycobacterial containment by co-culturing with H37Rv-infected monocyte-derived macrophages and autologous pre-primed effector T-cells with or without MDSCs. Mycobacterial containment was measured by plating colony forming units (CFU). Results: MDSCs (CD15+HLA-DR-CD33+) had significantly higher median frequencies (IQR) in patients with active TB (n=10) versus LTBI (n= 10) [8.2% (6.8-10.7) versus 42.2% (27-56) respectively; p=0.001]. Compared to MDSC-depleted peripheral blood mononuclear and effector T cell populations, dilutions of purified MDSCs isolated from active TB patients suppressed T-cell proliferation by up to 72% (n=6; p=0.03) and significantly subverted effector T-cell-mediated containment of H37Rv in monocyte-derived macrophages (n=7; 0.6% versus 8.5%; p=0.02). Conclusion: Collectively, these data suggest that circulating MDSCs are induced during active TB disease and can functionally suppress T-cell proliferation and subvert mycobacterial containment. These data may inform the design of vaccines and immunotherapeutic interventions against TB but further studies are required to understand the mechanisms underpinning the effects of MDSCs.


Subject(s)
Granulocytes/immunology , Latent Tuberculosis/immunology , Microbial Viability/immunology , Mycobacterium tuberculosis/genetics , Myeloid-Derived Suppressor Cells/immunology , Tuberculosis, Pulmonary/immunology , Adult , Cell Proliferation , Coculture Techniques , Female , HLA-DR Antigens/metabolism , Humans , Hydrolases/immunology , Latent Tuberculosis/blood , Latent Tuberculosis/epidemiology , Latent Tuberculosis/microbiology , Lewis X Antigen/metabolism , Macrophages/immunology , Male , Middle Aged , Mycobacterium tuberculosis/isolation & purification , Preliminary Data , Sialic Acid Binding Ig-like Lectin 3/metabolism , South Africa/epidemiology , T-Lymphocytes/immunology , Tuberculosis, Pulmonary/blood , Tuberculosis, Pulmonary/epidemiology , Tuberculosis, Pulmonary/microbiology
9.
J Clin Microbiol ; 58(10)2020 09 22.
Article in English | MEDLINE | ID: mdl-32727831

ABSTRACT

The diagnosis of tuberculosis (TB) in HIV-infected patients is challenging. Both a urinary lipoarabinomannan (LAM) test (Alere TB LAM) and GeneXpert-MTB/RIF (Xpert) are useful for the diagnosis of TB. However, how to optimally integrate Xpert and LAM tests into clinical practice algorithms remain unclear. We performed a post hoc analysis of 561 HIV-infected sputum-expectorating patients (median CD4 count of 130 cells/ml) from a previously published randomized controlled trial evaluating the LAM test in hospitalized HIV-infected patients with suspected TB. We evaluated 5 different diagnostic strategies using sputum culture as a reference standard (Xpert alone, LAM alone, sequential Xpert followed by LAM and vice versa [LAM in Xpert-negative patients and Xpert in LAM-negative patients], and both tests concurrently [LAM + Xpert]). A cost-consequence analysis was performed. Strategy-specific sensitivity and specificity, using culture as a reference, were similar with the Xpert-only and sequential and concurrent strategies. However, when any positive TB-specific test was used as a reference, the incremental yield of LAM over Xpert was 29.6% (45/152) and that of Xpert over LAM was 75% (84/11). The incremental yield of LAM increased with decreasing CD4 count. The costs per TB case diagnosed were similar for the sequential and concurrent strategies ($1,617 to $1,626). In sputum-expectorating hospitalized patients with advanced HIV and access to both tests, concurrent testing with Xpert and LAM may be the best strategy for diagnosing TB. These data inform clinical practice in settings where TB and HIV are endemic.


Subject(s)
HIV Infections , Mycobacterium tuberculosis , Tuberculosis , HIV Infections/complications , Humans , Lipopolysaccharides , Mycobacterium tuberculosis/genetics , Sensitivity and Specificity , Silver , Sputum , Tuberculosis/complications , Tuberculosis/diagnosis
10.
Int J Infect Dis ; 96: 240-243, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32339714

ABSTRACT

OBJECTIVES: Between-person variability in T-cell-specific interferon-gamma release assay (IGRA) responses and discordance between IGRA test formats are poorly understood. METHODS: We evaluated the IFN-γ responses (QuantiFERON-TB Gold-In-Tube [QFT-GIT] and TSPOT-TB) stratified according to the Mycobacterium tuberculosis spoligotype of the culture isolate obtained from the same patients with confirmed active tuberculosis (n = 91). We further analysed differences within the RD-1-encoding ESX-1 region between the different strain types using whole genome sequencing. RESULTS: In HIV-uninfected patients, TSPOT.TB and QFT-GIT IFN-γ responses were 5-fold (p < 0.01) and 2-fold higher (p < 0.05) for those infected with family 33 compared to the LAM strain (additionally, TSPOT.TB responses were 5.6-fold [p < 0.05] and 2.6-fold higher [p < 0.05] for the patients infected with the family 33 versus the X strain and Beijing versus the LAM strain, respectively). Multivariate analysis revealed that strain type (determined by spoligotyping) was independently associated with the magnitude of the IGRA response (varied by IGRA test type) and this is likely explained by variability in the ESX-1 region of Mycobacteriumtuberculosis (determined by next-generation sequencing). CONCLUSIONS: These data have implications for the understanding of between-person heterogeneity in IGRA responses, Mycobateriumtuberculosis-specific host immunity, and the discordance between different IGRA test formats.


Subject(s)
Antigens, Bacterial/immunology , Bacterial Proteins/immunology , Interferon-gamma/metabolism , Mycobacterium tuberculosis/immunology , Tuberculosis, Pulmonary/immunology , Adult , Antigens, Bacterial/genetics , Bacterial Proteins/genetics , Beijing , Female , Genotype , Humans , Interferon-gamma Release Tests , Male , Middle Aged , Mycobacterium tuberculosis/isolation & purification , T-Lymphocytes/immunology
11.
Int J Infect Dis ; 95: 246-252, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32247825

ABSTRACT

BACKGROUND: There are limited data about Xpert-Ultra performance in different settings, in HIV-infected persons, in those with a history of previous TB, and with trace readouts. METHODS: We evaluated the relative accuracy of Xpert-MTB/RIF and Xpert-Ultra in 272 selected but well-characterized archived sputum samples. Of these, 168 were culture-positive (64/168 smear-positive and 104/168 smear-negative), and 104 were culture-negative (102/104 from patients with previous TB and 2/104 from patients without a TB history). Assay-specific limit-of-detection (LOD) experiments were conducted using serial dilutions of Mycobacterium tuberculosis H37Rv. RESULTS: Overall sensitivity (95%CI) in smear-negative culture-positive samples for Xpert-MTB/RIF and Xpert-Ultra were 71.2% (62.5-79.9) and 77% (68.9-85.1), respectively (and in HIV-infected persons: 63.5% (50-76.1) and 73.1% (61.1-85.2), respectively). The LOD for Xpert-Ultra was lower (9 versus 184 CFU/ml). There were a total of 9/272 (3.3%) Xpert Ultra trace readouts (6/104 [5.8%]) in smear-negative culture-positive persons, and 3/102 (3%) in culture-negative non-TB persons with a history of previous TB). CONCLUSIONS: Xpert-Ultra had a lower LOD compared to Xpert-MTB/RIF. A small proportion of samples (<5%) from culture-negative patients but with a history of previous TB had a likely false-positive trace readout. These data inform the management of patients with suspected TB in endemic settings.


Subject(s)
Expert Systems , Real-Time Polymerase Chain Reaction/methods , Tuberculosis, Pulmonary/diagnosis , Adult , Aged , Female , HIV Infections/complications , HIV Infections/epidemiology , Humans , Limit of Detection , Male , Middle Aged , Mycobacterium tuberculosis , Sensitivity and Specificity , Sputum/microbiology , Tuberculosis, Pulmonary/complications , Young Adult
12.
Am J Respir Crit Care Med ; 201(10): 1277-1291, 2020 05 15.
Article in English | MEDLINE | ID: mdl-31860339

ABSTRACT

Rationale: A human model to better understand tuberculosis immunopathogenesis and facilitate vaccine development is urgently needed.Objectives: We evaluated the feasibility, safety, and immunogenicity of live bacillus Calmette-Guérin (BCG) in a lung-oriented controlled human infection model.Methods: We recruited 106 healthy South African participants with varying degrees of tuberculosis susceptibility. Live BCG, sterile PPD, and saline were bronchoscopically instilled into separate lung segments (n = 65). A control group (n = 34) underwent a single bronchoscopy without challenge. The primary outcome was safety. Cellular and antibody immune signatures were identified in BAL before and 3 days after challenge using flow cytometry, ELISA, RNA sequencing, and mass spectrometry.Measurements and Main Results: The frequency of adverse events was low (9.4%; n = 10), similar in the challenge versus control groups (P = 0.8), and all adverse events were mild and managed conservatively in an outpatient setting. The optimal PPD and BCG dose was 0.5 TU and 104 cfu, respectively, based on changes in BAL cellular profiles (P = 0.02) and antibody responses (P = 0.01) at incremental doses before versus after challenge. At 104 versus 103 cfu BCG, there was a significant increase in number of differentially expressed genes (367 vs. 3; P < 0.001) and dysregulated proteins (64 vs. 0; P < 0.001). Immune responses were highly setting specific (in vitro vs. in vivo) and compartment specific (BAL vs. blood) and localized to the challenged lung segments.Conclusions: A lung-oriented mycobacterial controlled human infection model using live BCG and PPD is feasible and safe. These data inform the study of tuberculosis immunopathogenesis and strategies for evaluation and development of tuberculosis vaccine candidates.


Subject(s)
Adjuvants, Immunologic/administration & dosage , BCG Vaccine/administration & dosage , Bronchoscopy , Immunogenicity, Vaccine , Tuberculin/administration & dosage , Tuberculosis/prevention & control , Administration, Topical , Adult , Feasibility Studies , Female , Humans , Immunity, Mucosal , Male , Young Adult
13.
Sci Rep ; 9(1): 4334, 2019 03 13.
Article in English | MEDLINE | ID: mdl-30867477

ABSTRACT

The intramuscular progestin-only injectable contraceptive, depo-medroxyprogesterone acetate (DMPA-IM), is more widely used in Sub-Saharan Africa than another injectable contraceptive, norethisterone enanthate (NET-EN). Epidemiological data show a significant 1.4-fold increased risk of HIV-1 acquisition for DMPA-IM usage, while no such association is shown from limited data for NET-EN. We show that MPA, unlike NET, significantly increases R5-tropic but not X4-tropic HIV-1 replication ex vivo in human endocervical and ectocervical explant tissue from pre-menopausal donors, at physiologically relevant doses. Results support a mechanism whereby MPA, unlike NET, acts via the glucocorticoid receptor (GR) to increase HIV-1 replication in cervical tissue by increasing the relative frequency of CD4+ T cells and activated monocytes. We show that MPA, unlike NET, increases mRNA expression of the CD4 HIV-1 receptor and CCR5 but not CXCR4 chemokine receptors, via the GR. However, increased density of CD4 on CD3+ cells was not observed with MPA by flow cytometry of digested tissue. Results suggest that DMPA-IM may increase HIV-1 acquisition in vivo at least in part via direct effects on cervical tissue to increase founder R5-tropic HIV-1 replication. Our findings support differential biological mechanisms and disaggregation of DMPA-IM and NET-EN regarding HIV-1 acquisition risk category for use in high risk areas.


Subject(s)
Cervix Uteri/virology , Contraceptive Agents, Hormonal/pharmacology , HIV-1/pathogenicity , Medroxyprogesterone Acetate/pharmacology , Norethindrone/pharmacology , Contraceptive Agents, Hormonal/administration & dosage , Dose-Response Relationship, Drug , Female , HEK293 Cells , HIV Infections/transmission , HIV-1/physiology , Humans , In Vitro Techniques , Medroxyprogesterone Acetate/administration & dosage , RNA, Messenger/genetics , Receptors, CCR5/genetics , Risk Factors , Virus Replication/drug effects
14.
J Infect Dis ; 219(8): 1329-1337, 2019 04 08.
Article in English | MEDLINE | ID: mdl-30452655

ABSTRACT

BACKGROUND: The effects of the widely used progestin-only injectable contraceptives, medroxyprogesterone acetate (MPA) and norethisterone acetate (NET-A), on host susceptibility to Mycobacterium tuberculosis (Mtb) are unknown. METHODS: We recruited human immunodeficiency virus-uninfected females, not taking any contraceptives, from Cape Town, South Africa, to evaluate the effect of MPA, NET-A, and dexamethasone on Mtb containment in monocyte-derived macrophages co-incubated with purified protein derivative (PPD)-driven peripheral blood-derived effector cells. RESULTS: MPA (P < .005) and dexamethasone (P < .01), but not NET-A, significantly attenuated Mtb containment in Mtb-infected macrophages co-cultured with PPD-driven effector cells at physiologically relevant concentrations and in a dose-dependent manner. Antagonizing the glucocorticoid receptor with mifepristone (RU486) abrogated the reduction in Mtb containment. In PPD-stimulated peripheral blood mononuclear cells, MPA and dexamethasone, but not NET-A, upregulated (median [interquartile range]) regulatory T cells (5.3% [3.1%-18.2%]; P < .05), reduced CD4+ T-cell interferon-γ (21% [0.5%-28%]; P < .05) and granzyme B production (12.6% [7%-13.5%]; P < .05), and reduced CD8+ perforin activity (2.2% [0.1%-7%]; P < .05). RU486 reversed regulatory T-cell up-regulation and the inhibitory effect on Th1 and granzyme/perforin-related pathways. CONCLUSIONS: MPA, but not NET-A, subverts mycobacterial containment in vitro and downregulates pathways associated with protective CD8+- and CD4+-related host immunity via the glucocorticoid receptor. These data potentially inform the selection and use of injectable contraceptives in tuberculosis-endemic countries.


Subject(s)
Contraceptive Agents, Female/adverse effects , Immunity/drug effects , Medroxyprogesterone Acetate/adverse effects , Mycobacterium tuberculosis/immunology , Receptors, Glucocorticoid/drug effects , Tuberculosis, Pulmonary/immunology , Contraceptive Agents, Female/administration & dosage , Dexamethasone/administration & dosage , Dexamethasone/adverse effects , Disease Susceptibility/immunology , Dose-Response Relationship, Drug , Female , Flow Cytometry , Humans , Immunity, Cellular/drug effects , Medroxyprogesterone Acetate/administration & dosage , Norethindrone Acetate/administration & dosage , Norethindrone Acetate/adverse effects , T-Lymphocytes, Regulatory/drug effects
15.
Cancer Immunol Immunother ; 68(1): 71-83, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30283982

ABSTRACT

Breast cancer remains one of the leading causes of cancer-associated death worldwide. Conventional treatment is associated with substantial toxicity and suboptimal efficacy. We, therefore, developed and evaluated the in vitro efficacy of an autologous dendritic cell (DC) vaccine to treat breast cancer. We recruited 12 female patients with stage 1, 2, or 3 breast cancer and matured their DCs with autologous tumour-specific lysate, a toll-like receptor (TLR)-3 and 7/8 agonist, and an interferon-containing cocktail. The efficacy of the vaccine was evaluated by its ability to elicit a cytotoxic T-lymphocyte response to autologous breast cancer cells in vitro. Matured DCs (≥ 60% upregulation of CD80, CD86, CD83, and CCR7) produced high levels of the Th1 effector cytokine, IL12-p70 (1.2 ng/ml; p < 0.0001), compared to DCs pulsed with tumour lysate, or matured with an interferon-containing cocktail alone. We further showed that matured DCs enhance antigen-specific CD8 + T-cell responses to HER-2 (4.5%; p < 0.005) and MUC-1 (19%; p < 0.05) tetramers. The mature DCs could elicit a robust and dose-dependent antigen-specific cytotoxic T-lymphocyte response (65%) which was tumoricidal to autologous breast cancer cells in vitro compared to T-lymphocytes that were primed with autologous lysate loaded-DCs (p < 0.005). Lastly, we showed that the mature DCs post-cryopreservation maintained high viability, maintained their mature phenotype, and remained free of endotoxins or mycoplasma. We have developed a DC vaccine that is cytotoxic to autologous breast cancer cells in vitro. The tools and technology generated here will now be applied to a phase I/IIa clinical trial.


Subject(s)
Breast Neoplasms/therapy , Cancer Vaccines/immunology , Dendritic Cells/immunology , Immunotherapy, Adoptive/methods , Adult , Aged , Breast Neoplasms/immunology , Breast Neoplasms/pathology , Coculture Techniques , Cytokines/immunology , Cytokines/metabolism , Female , Humans , Lymphocyte Activation/immunology , Middle Aged , T-Lymphocytes, Cytotoxic/immunology , Th1 Cells/immunology , Th1 Cells/metabolism , Tumor Cells, Cultured
16.
PLoS One ; 13(4): e0196043, 2018.
Article in English | MEDLINE | ID: mdl-29698514

ABSTRACT

High usage of progestin-only injectable contraceptives, which include the intramuscular injectables depo-medroxyprogesterone acetate (DMPA-IM, Depo-Provera) and norethisterone (NET) enanthate (NET-EN or Nur-Isterate), correlates worldwide with areas of high HIV-1 prevalence. Epidemiological data show a significant association between usage of DMPA-IM and increased HIV-1 acquisition but no such association from limited data for NET-EN. Whether MPA and NET have similar effects on HIV-1 acquisition and pathogenesis, and the relationship between these effects and the dose of MPA, are critical issues for women's health and access to suitable and safe contraceptives. We show for the first time that MPA, unlike NET, significantly increases HIV-1 replication in peripheral blood mononuclear cells (PBMCs) and a cervical cell line model. The results provide novel evidence for a biological mechanism whereby MPA, acting via the glucocorticoid receptor (GR), increases HIV-1 replication by at least in part increasing expression of the CCR5 HIV-1 coreceptor on target T-lymphocytes. MPA, unlike NET, also increases activation of T-cells and increases the CD4/CD8 ratio, suggesting that multiple mechanisms are involved in the MPA response. Our data offer strong support for different biological mechanisms for MPA versus NET, due to their differential GR activity. The dose-dependence of the MPA response suggests that significant effects are observed within the range of peak serum levels of progestins in DMPA-IM but not NET-EN users. Dose-response results further suggest that effects of contraceptives containing MPA on HIV-1 acquisition and disease progression may be critically dependent on dose, time after injection and intrinsic factors that affect serum concentrations in women.


Subject(s)
HIV-1/physiology , Medroxyprogesterone Acetate/pharmacology , Receptors, CCR5/metabolism , Receptors, Glucocorticoid/metabolism , Virus Replication/drug effects , CD4 Antigens/genetics , CD4 Antigens/metabolism , CD4-CD8 Ratio , Cell Line , Female , HEK293 Cells , HIV-1/drug effects , Humans , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/virology , Mifepristone/pharmacology , Norethindrone/pharmacology , RNA Interference , RNA, Small Interfering/metabolism , Receptors, CCR5/genetics , Receptors, Glucocorticoid/antagonists & inhibitors , Receptors, Glucocorticoid/genetics , T-Lymphocytes/cytology , T-Lymphocytes/drug effects , T-Lymphocytes/metabolism , Up-Regulation/drug effects
17.
Lancet Infect Dis ; 17(4): 441-450, 2017 04.
Article in English | MEDLINE | ID: mdl-28063795

ABSTRACT

BACKGROUND: Inadequate case detection results in high levels of undiagnosed tuberculosis in sub-Saharan Africa. Data for the effect of new diagnostic tools when used for community-based intensified case finding are not available, so we investigated whether the use of sputum Xpert-MTB/RIF and the Determine TB LAM urine test in two African communities could be effective. METHODS: In a pragmatic, randomised, parallel-group trial with individual randomisation stratified by country, we compared sputum Xpert-MTB/RIF, and if HIV-infected, the Determine TB LAM urine test (novel diagnostic group), with laboratory-based sputum smear microscopy (routine diagnostic group) for intensified case finding in communities with high tuberculosis and HIV prevalence in Cape Town, South Africa, and Harare, Zimbabwe. Participants were randomly assigned (1:1) to these groups with computer-generated allocation lists, using culture as the reference standard. In Cape Town, participants were randomised and tested at an Xpert-equipped mobile van, while in Harare, participants were driven to a local clinic where the same diagnostic tests were done. The primary endpoint was the proportion of culture-positive tuberculosis cases initiating tuberculosis treatment in each study group at 60 days. This trial is registered at ClinicalTrials.gov, number NCT01990274. FINDINGS: Between Oct 18, 2013, and March 31, 2015, 2261 individuals were screened and 875 (39%) of these met the criteria for diagnostic testing. 439 participants were randomly assigned to the novel group and 436 to the routine group. 74 (9%) of 875 participants had confirmed tuberculosis. If late culture-based treatment initiation was excluded, more patients with culture-positive tuberculosis were initiated on treatment in the novel group at 60 days (36 [86%] of 42 in the novel group vs 18 [56%] of 32 in the routine group). Thus the difference in the proportion initiating treatment between groups was 29% (95% CI 9-50, p=0·0047) and 53% more patients initiated therapy in the novel diagnostic group than in the routine diagnostic group. One culture-positive patient was treated based only on a positive LAM test. INTERPRETATION: Compared with traditional tools, Xpert-MTB/RIF for community-based intensified case finding in HIV and tuberculosis-endemic settings increased the proportion of patients initiating treatment. By contrast, urine LAM testing was not found to be useful for intensive case finding in this setting. FUNDING: European and Developing Countries Clinical Trials Partnership and South African Medical Research Council.


Subject(s)
Ambulatory Care Facilities , Diagnostic Tests, Routine/statistics & numerical data , Sensitivity and Specificity , Tuberculosis/diagnosis , Adult , Africa South of the Sahara , Developing Countries , Female , Humans , Male , Mycobacterium tuberculosis/isolation & purification , Prevalence , Sputum , Time Factors , Tuberculosis/therapy , Tuberculosis/transmission
18.
Sci Rep ; 6: 17850, 2016 Feb 10.
Article in English | MEDLINE | ID: mdl-26860462

ABSTRACT

Although molecular tests for drug-resistant TB perform well on culture isolates, their accuracy using clinical samples, particularly from TB and HIV-endemic settings, requires clarification. The MTBDRplus and MTBDRsl line probe assays were evaluated in 181 sputum samples and 270 isolates from patients with culture-confirmed drug-sensitive-TB, MDR-TB, or XDR-TB. Phenotypic culture-based testing was the reference standard. Using sputum, the sensitivities for resistance was 97.7%, 95.4%, 58.9%, 61.6% for rifampicin, isoniazid, ofloxacin, and amikacin, respectively, whereas the specificities were 91.8%, 89%, 100%, and 100%, respectively. MTBDRsl sensitivity differed in smear-positive vs. smear-negative samples (79.2% vs. 20%, p < 0.0001 for ofloxacin; 72.9% vs. 37%, p = 0.0023 for amikacin) but not by HIV status. If used sequentially, MTBDRplus and MTBDRsl could rule-in XDR-TB in 78.5% (22/28) and 10.5% (2/19) of smear-positive and smear-negative samples, respectively. On culture isolates, the sensitivity for resistance to rifampicin, isoniazid, ofloxacin, and amikacin was 95.1%, 96.1%, 72.3% and 76.6%, respectively, whereas the specificities exceeded 96%. Using a sequential testing approach, rapid sputum-based diagnosis of fluoroquinolone or aminoglycoside-resistant TB is feasible only in smear-positive samples, where rule-in value is good. Further investigation is required in samples that test susceptible in order to rule-out second-line drug resistance.


Subject(s)
Biological Assay/methods , Drug Resistance, Multiple, Bacterial , Extensively Drug-Resistant Tuberculosis/diagnosis , Mycobacterium tuberculosis/isolation & purification , Sputum/microbiology , Adolescent , Adult , Aged , Aged, 80 and over , Antitubercular Agents/therapeutic use , Extensively Drug-Resistant Tuberculosis/microbiology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prognosis , Rifampin/therapeutic use , Young Adult
19.
Am J Reprod Immunol ; 71(6): 505-12, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24547700

ABSTRACT

Whether hormonal contraceptives increase HIV-1 acquisition, transmission and disease progression are critical questions. Clinical research has been hampered by a lack of understanding that different progestins used in contraception exhibit differential off-target effects via steroid receptors other than the progesterone receptor. Of particular, relevance is the relative effects of medroxyprogesterone acetate (MPA) and norethisterone enanthate (NET-EN), widely used as injectable contraceptives in sub-Saharan Africa. While most high-quality clinical studies find no increased risk for HIV-1 acquisition with oral contraception or injectable NET-EN, most do find an increase with MPA, particularly in young women. Furthermore, mounting evidence from animal, ex vivo and biochemical studies are consistent with MPA acting to increase HIV-1 acquisition and pathogenesis, via mechanisms involving glucocorticoid-like effects on gene expression, in particular genes involved in immune function. We report that MPA, unlike NET and progesterone, represses inflammatory genes in human PBMCs in a dose-dependent manner, via the glucocorticoid receptor (GR), at concentrations within the physiologically relevant range. These and published results collectively suggest that the differential GR activity of MPA versus NET may be a mechanism whereby MPA, unlike NET or progesterone, differentially modulates HIV-1 acquisition and pathogenesis in target cells where the GR is the predominant steroid receptor expressed.


Subject(s)
HIV Infections/pathology , Immunosuppression Therapy , Medroxyprogesterone Acetate/pharmacology , Norethindrone/analogs & derivatives , Receptors, Glucocorticoid/immunology , Africa South of the Sahara , Contraceptive Agents/pharmacology , Contraceptive Agents, Female/pharmacology , Contraceptives, Oral, Synthetic/pharmacology , Female , HIV Infections/transmission , HIV-1/pathogenicity , Humans , Norethindrone/pharmacology , Progesterone Congeners/pharmacology
20.
PLoS One ; 8(5): e62895, 2013.
Article in English | MEDLINE | ID: mdl-23658782

ABSTRACT

The glucocorticoid receptor (GR) regulates several physiological functions, including immune function and apoptosis. The HIV-1 virus accessory protein, viral protein R (Vpr), can modulate the transcriptional response of the GR. Glucocorticoids (GCs) and Vpr have been reported to induce apoptosis in various cells, including T-cells. We have previously shown that the injectable contraceptive, medroxyprogesterone acetate (MPA) is a partial to full agonist for the GR, unlike norethisterone acetate (NET-A). We investigated the functional cross talk between the GR and Vpr in inducing apoptosis in CD4(+) T-cells, in the absence and presence of GCs and these progestins, as well as progesterone. By using flow cytometry, we show that, in contrast to NET-A and progesterone, the synthetic GR ligand dexamethasone (Dex), cortisol and MPA induce apoptosis in primary CD4(+) T-cells. Furthermore, the C-terminal part of the Vpr peptide, or HIV-1 pseudovirus, together with Dex or MPA further increased the apoptotic phenotype, unlike NET-A and progesterone. By a combination of Western blotting, PCR and the use of receptor- selective agonists, we provide evidence that the GR and the estrogen receptor are the only steroid receptors expressed in peripheral blood mononuclear cells. These results, together with the findings that RU486, a GR antagonist, prevents Dex-, MPA- and Vpr-mediated apoptosis, provide evidence for the first time that GR agonists or partial agonists increase apoptosis in primary CD4(+) T-cells via the GR. We show that apoptotic induction involves differential expression of key apoptotic genes by both Vpr and GCs/MPA. This work suggests that contraceptive doses of MPA but not NET-A or physiological doses of progesterone could potentially accelerate depletion of CD4(+) T-cells in a GR-dependent fashion in HIV-1 positive women, thereby contributing to immunodeficiency. The results imply that choice of progestin used in contraception may be critical to susceptibility and progression of diseases such as HIV-1.


Subject(s)
CD4-Positive T-Lymphocytes/drug effects , Contraceptive Agents, Female/pharmacology , Gene Products, vpr/pharmacology , HIV-1/chemistry , Medroxyprogesterone Acetate/pharmacology , Norethindrone/analogs & derivatives , Receptors, Glucocorticoid/genetics , Amino Acid Sequence , Apoptosis , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/metabolism , Cells, Cultured , Dexamethasone/pharmacology , Gene Expression Regulation , Humans , Hydrocortisone/pharmacology , Mifepristone/pharmacology , Molecular Sequence Data , Norethindrone/pharmacology , Norethindrone Acetate , Progesterone/pharmacology , Receptors, Estrogen/genetics , Receptors, Estrogen/metabolism , Receptors, Glucocorticoid/antagonists & inhibitors , Receptors, Glucocorticoid/metabolism , Signal Transduction
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