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1.
Future Sci OA ; 9(8): FSO882, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37621850

RESUMO

Aim: The ability of a hen egg white bovine colostrum supplement to prevent severe COVID-19 was tested in a double-blind randomized control study. Methods: Adults with mild/moderate COVID-19, risk factors for severe disease, and within 5 days of symptom onset were assigned to the intervention (n = 77) or placebo (n = 79) arms. Symptoms were documented until day 42 post-enrollment and viral clearance was assessed at 11-13 days post-symptom onset. Results: One participant developed severe COVID-19. The severe-type symptom score was lower in the active arm at 11-13 days post-symptom onset (p = 0.049). Chest pain, fever/chills, joint pain/malaise, and sore throat were significantly less frequent in the active arm. No differences in viral clearance were observed. Conclusion: The intervention reduced symptoms of mild/moderate COVID-19. Clinical Trial Registration: DOH-27-062021-9191 (South African National Clinical Trials Register).


Natural proteins found in milk (lactoferrin) and egg white (ovotransferrin and lysozyme) could have therapeutic value in COVID-19 through their effects on the immune system. We identified bovine colostrum and hen egg white powders containing adequate quantities of these proteins. We investigated whether short-term daily consumption of a hen egg white and bovine colostrum mixture (reconstituted with glycerin and water) could reduce the risk of progression to severe disease and assist in the recovery of patients with mild or moderate COVID-19. Adults with mild or moderate COVID-19 who were within 5 days of symptom onset and had risk factors for severe disease were enrolled, and randomly assigned to take a hen egg white and bovine colostrum mixture or placebo mixture twice daily for 5 days, and then followed up telephonically for 6 weeks. The main findings were that consumption of the hen egg white and bovine colostrum mixture was associated with fewer protocol-defined severe-type symptoms overall, and in particular lower frequencies of joint pain/malaise, chest pain, fever/chills, and sore throat. Only one individual developed severe COVID-19 and therefore the effect of the intervention on reducing the risk of progression to severe disease could not be assessed. The results of this study suggest that consumption of the hen egg white bovine colostrum mixture within a few days of symptom onset lessens symptoms in people with mild or moderate COVID-19.

2.
Front Immunol ; 12: 631410, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33897687

RESUMO

Mucosal associated invariant T (MAIT) cells are a class of innate-like T cells that utilize a semi-invariant αß T cell receptor to recognize small molecule ligands produced by bacteria and fungi. Despite growing evidence that immune cells at mucosal surfaces are often phenotypically and functionally distinct from those in the peripheral circulation, knowledge about the characteristics of MAIT cells at the lung mucosal surface, the site of exposure to respiratory pathogens, is limited. HIV infection has been shown to have a profound effect on the number and function of MAIT cells in the peripheral blood, but its effect on lung mucosal MAIT cells is unknown. We examined the phenotypic, functional, and transcriptomic features of major histocompatibility complex (MHC) class I-related (MR1)-restricted MAIT cells from the peripheral blood and bronchoalveolar compartments of otherwise healthy individuals with latent Mycobacterium tuberculosis (Mtb) infection who were either HIV uninfected or HIV infected. Peripheral blood MAIT cells consistently co-expressed typical MAIT cell surface markers CD161 and CD26 in HIV-negative individuals, while paired bronchoalveolar MAIT cells displayed heterogenous expression of these markers. Bronchoalveolar MAIT cells produced lower levels of pro-inflammatory cytokine IFN-γ and expressed higher levels of co-inhibitory markers PD-1 and TIM-3 than peripheral MAIT cells. HIV infection resulted in decreased frequencies and pro-inflammatory function of peripheral blood MAIT cells, while in the bronchoalveolar compartment MAIT cell frequency was decreased but phenotype and function were not significantly altered. Single-cell transcriptomic analysis demonstrated greater heterogeneity among bronchoalveolar compared to peripheral blood MAIT cells and suggested a distinct subset in the bronchoalveolar compartment. The transcriptional features of this bronchoalveolar subset were associated with MAIT cell tissue repair functions. In summary, we found previously undescribed phenotypic and transcriptional heterogeneity of bronchoalveolar MAIT cells in HIV-negative people. In HIV infection, we found numeric depletion of MAIT cells in both anatomical compartments but preservation of the novel phenotypic and transcriptional features of bronchoalveolar MAIT cells.


Assuntos
Perfilação da Expressão Gênica , Infecções por HIV/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Pulmão/citologia , Antígenos de Histocompatibilidade Menor/imunologia , Células T Invariantes Associadas à Mucosa/imunologia , Mucosa Respiratória/citologia , Mucosa Respiratória/imunologia , Adulto , Feminino , Infecções por HIV/microbiologia , Humanos , Imunidade nas Mucosas , Tuberculose Latente/imunologia , Pulmão/imunologia , Pulmão/virologia , Masculino , Pessoa de Meia-Idade , Células T Invariantes Associadas à Mucosa/classificação , Mucosa/citologia , Mucosa/imunologia , Fenótipo , Transcriptoma , Adulto Jovem
3.
Front Immunol ; 11: 864, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508817

RESUMO

The mechanisms by which HIV increases susceptibility to tuberculosis and other respiratory infections are incompletely understood. We used transcriptomics of paired whole bronchoalveolar lavage cells (BLCs) and peripheral blood mononuclear cells to compare the effect of HIV at the lung mucosal surface and in peripheral blood. The majority of HIV-induced differentially expressed genes (DEGs) were specific to either the peripheral or lung mucosa compartments (1,307/1,404, 93%). Type I interferon signaling was the dominant signature of DEGs in HIV-positive blood but not in HIV-positive BLCs. DEGs in the HIV-positive BLCs were significantly enriched for infiltration with cytotoxic CD8+ T cells. Higher expression of type 1 interferon transcripts in peripheral CD8+ T cells and representative transcripts and proteins in BLCs-derived CD8+ T cells during HIV infection, including IFNG (IFN-gamma), GZMB (Granzyme B), and PDCD1 (PD-1), was confirmed by cell-subset specific transcriptional analysis and flow cytometry. Thus, we report that a whole transcriptomic approach revealed qualitatively distinct effects of HIV in blood and bronchoalveolar compartments. Further work exploring the impact of distinct type I interferon programs and functional features of CD8+ T cells infiltrating the lung mucosa during HIV infection may provide novel insights into HIV-induced susceptibility to respiratory pathogens.


Assuntos
Perfilação da Expressão Gênica , Infecções por HIV/imunologia , Inflamação/genética , Leucócitos Mononucleares/imunologia , Alvéolos Pulmonares/imunologia , Adolescente , Adulto , Lavagem Broncoalveolar , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Estudos de Coortes , Feminino , Granzimas/genética , Humanos , Inflamação/virologia , Interferon gama/genética , Leucócitos Mononucleares/virologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Alvéolos Pulmonares/virologia , Adulto Jovem
4.
Microorganisms ; 8(1)2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31963608

RESUMO

Whole-genome sequence (WGS) analyses were employed to investigate the genomic epidemiology of extensively drug-resistant Klebsiella pneumoniae strains, focusing on the carbapenem resistance-encoding determinants, mobile genetic support, clonal and epidemiological relationships. A total of ten isolates were obtained from patients admitted to the intensive care unit (ICU) in a public hospital in South Africa. Five isolates were from rectal swabs of colonized patients and five from blood cultures of patients with invasive carbapenem-resistant infections. Following microbial identification and antibiotic susceptibility tests, the isolates were subjected to WGS on the Illumina MiSeq platform. All the isolates showed genotypic resistance to tested ß-lactams (NDM-1, OXA-1, CTX-M-15, TEM-1B, SHV-1) and other antibiotics. All but one isolate belonged to the ST152 with a novel sequence type, ST3136, differing by a single-locus variant. The isolates had the same plasmid multilocus sequence type (IncF[K12:A-:B36]) and capsular serotype (KL149), supporting the epidemiological linkage between the clones. Resistance to carbapenems in the 10 isolates was conferred by the blaNDM-1 mediated by the acquisition of multi-replicon [ColRNAI, IncFIB(pB171), Col440I, IncFII, IncFIB(K) and IncFII(Yp)] p18-43_01 plasmid. These findings suggest that the acquisition of blaNDM-1-bearing plasmid structure (p18-43_01), horizontal transfer and clonal dissemination facilitate the spread of carbapenemases in South Africa. This emphasizes the importance of targeted infection control measures to prevent dissemination.

5.
Commun Biol ; 2: 203, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31231693

RESUMO

Mucosal-associated invariant T (MAIT) cells typically express a TRAV1-2+ semi-invariant TCRα that enables recognition of bacterial, mycobacterial, and fungal riboflavin metabolites presented by MR1. MAIT cells are associated with immune control of bacterial and mycobacterial infections in murine models. Here, we report that a population of pro-inflammatory TRAV1-2+ CD8+ T cells are present in the airways and lungs of healthy individuals and are enriched in bronchoalveolar fluid of patients with active pulmonary tuberculosis (TB). High-throughput T cell receptor analysis reveals oligoclonal expansions of canonical and donor-unique TRAV1-2+ MAIT-consistent TCRα sequences within this population. Some of these cells demonstrate MR1-restricted mycobacterial reactivity and phenotypes suggestive of MAIT cell identity. These findings demonstrate enrichment of TRAV1-2+ CD8+ T cells with MAIT or MAIT-like features in the airways during active TB and suggest a role for these cells in the human pulmonary immune response to Mycobacterium tuberculosis.


Assuntos
Linfócitos T CD8-Positivos/citologia , Células T Invariantes Associadas à Mucosa/imunologia , Tuberculose Pulmonar/imunologia , Animais , Brônquios/microbiologia , Líquido da Lavagem Broncoalveolar , Broncoscopia , Linfócitos T CD8-Positivos/microbiologia , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Sistema Imunitário , Inflamação , Intestinos/imunologia , Pulmão/imunologia , Pulmão/microbiologia , Camundongos , Antígenos de Histocompatibilidade Menor/imunologia , Células T Invariantes Associadas à Mucosa/microbiologia , Mycobacterium tuberculosis/imunologia , Oregon , Fenótipo , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , África do Sul , Tuberculose Pulmonar/microbiologia
6.
AAS Open Res ; 2: 25, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32382702

RESUMO

Background: Bronchoalveolar lavage (BAL) is indicated for medical evaluation of complex cases of lung disease.  There is limited data on the performance of tuberculosis (TB) microbiologic tests on BAL in such patients, particularly in human immunodeficiency virus (HIV) and TB endemic areas. Methods: We evaluated the performance of Mycobacterium tuberculosis (Mtb) culture and up to two simultaneous Xpert MTB/RIF tests on BAL fluid against a consensus clinical diagnosis in 98 medically complex patients undergoing bronchoscopy over a two-year period in Durban, South Africa. Results: TB was the most frequently diagnosed lung disease, found in 19 of 98 participants (19%) and was microbiologically proven in 14 of these (74%); 9 (47%) were culture positive and 5 were positive on at least one Xpert MTB/RIF assay. Immunosuppression prevalence was high (26% HIV-infected, 29% on immunosuppressive therapy and 4% on chemotherapy). Xpert MTB/RIF had low sensitivity (45%) and high specificity (99%) when assessed against the consensus clinical diagnosis. Compared to TB culture, a single Xpert MTB/RIF increased the diagnostic yield by 11% and a second Xpert MTB/RIF by a further 16%. Conclusion: Although Xpert MTB/RIF had a low sensitivity, sending two tests improved the microbiologically-proven diagnostic yield of bronchoscopy from 47% to 74% compared to culture alone.

7.
World Neurosurg ; 123: e574-e580, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30529520

RESUMO

BACKGROUND: In 2000, we advised against insertion of a ventriculoperitoneal shunt (VPS) in human immunodeficiency virus (HIV)-positive patients with tuberculous meningitis (TBM) complicated by hydrocephalus. However, this was in the era when combination antiretroviral therapy (ART) was not freely available in South Africa. In this subsequent preliminary report, we describe the outcome of ventriculoperitoneal shunting in patients with TBM and hydrocephalus who are HIV positive and receiving ART. METHODS: We compared a group of 15 HIV-positive patients with TBM and hydrocephalus on ART with a retrospective control group of 15 patients (demographically and clinically matched) but not on ART. All patients were otherwise managed similarly and evaluated at 1 month after VPS insertion. RESULTS: In historical controls, 10 patients died (66.7%) and no patient showed any improvement 1 month after shunting. In contrast, in the current group on ART, 4 patients died (26.7%), with 11 patients (73.3%) having a good outcome. Eight of 12 patients with grade 3 TBM had a good outcome, whereas all 3 with grade 1 TBM made a good recovery. CONCLUSIONS: The outcome of VP shunting in HIV-positive patients with TBM and hydrocephalus is markedly improved in patients on ART. Based on limited data from this study, we recommend that better grades of TBM (1 and 2) undergo immediate VPS surgery. Patients with grade 4 TBM should undergo a trial of external ventricular drainage and those who improve should undergo a definitive procedure. Further research is required for patients with grade 3 TBM to identify characteristics associated with better outcomes to allow for effective use of limited resources.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Hidrocefalia/cirurgia , Tuberculose Meníngea/complicações , Derivação Ventriculoperitoneal , Adulto , Criança , Pré-Escolar , Feminino , Infecções por HIV/mortalidade , Humanos , Hidrocefalia/complicações , Hidrocefalia/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Tuberculose Meníngea/mortalidade , Adulto Jovem
9.
Elife ; 62017 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-28130921

RESUMO

A hallmark of pulmonary tuberculosis is the formation of macrophage-rich granulomas. These may restrict Mycobacterium tuberculosis (Mtb) growth, or progress to central necrosis and cavitation, facilitating pathogen growth. To determine factors leading to Mtb proliferation and host cell death, we used live cell imaging to track Mtb infection outcomes in individual primary human macrophages. Internalization of Mtb aggregates caused macrophage death, and phagocytosis of large aggregates was more cytotoxic than multiple small aggregates containing similar numbers of bacilli. Macrophage death did not result in clearance of Mtb. Rather, it led to accelerated intracellular Mtb growth regardless of prior activation or macrophage type. In contrast, bacillary replication was controlled in live phagocytes. Mtb grew as a clump in dead cells, and macrophages which internalized dead infected cells were very likely to die themselves, leading to a cell death cascade. This demonstrates how pathogen virulence can be achieved through numbers and aggregation states.


Assuntos
Morte Celular , Endocitose , Macrófagos/microbiologia , Macrófagos/fisiologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Células Cultivadas , Humanos , Microscopia Intravital
10.
Tumour Biol ; 33(5): 1701-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22684816

RESUMO

Pleural effusion is a commonly encountered problem in clinical practice, and pleural fluid analysis is usually the first step towards identifying the underlying etiology. Numerous studies have been published analyzing the potential utility of measuring biomarkers in pleural fluid as possible indicators of a malignant effusion; however, there are no studies that have examined the presence of human epididymis 4 (HE4) in pleural effusions. The aims of this study were to assess pleural effusion and serum concentrations of HE4 in patients with different types of pleural effusions and to evaluate the diagnostic performance of HE4 in detecting malignant pleural effusion. A prospective cohort study was carried out of 88 consecutive patients presenting with pleural effusions. The patients were divided into three groups: 22 patients with transudative effusions, 32 patients with non-malignant exudative effusions, and 34 patients with malignant pleural effusions. Blood and pleural fluid HE4 levels were measured using immunoassay. Both serum HE4 levels and pleural effusion HE4 levels were significantly higher in patients with malignant effusions than in patients with transudative or non-malignant exudative effusions. A pleural fluid HE4 cutoff value of 1,675 pmol/L was found to predict malignant pleural effusions with a diagnostic sensitivity of 85.3 % and specificity of 90.7 %. The current study reports a novel finding of increased serum and pleural fluid HE4 levels in patients with malignant effusions compared to non-malignant effusions. This finding has the potential to strengthen the diagnostic performance of tumor markers in detecting malignant pleural effusions.


Assuntos
Exsudatos e Transudatos/metabolismo , Derrame Pleural Maligno/diagnóstico , Proteínas/metabolismo , Idoso , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Derrame Pleural Maligno/metabolismo , Curva ROC , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos
11.
Case Rep Pulmonol ; 2011: 323584, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22937424

RESUMO

Malignant rhabdoid tumor (MRT) is one of the most aggressive and lethal malignancies in pediatric oncology. Malignant rhabdoid tumor was initially described in 1978 as a rhabdomyosarcomatoid variant of a Wilms tumor because of its occurrence in the kidney and because of the resemblance of its cells to rhabdomyoblasts. The absence of muscular differentiation led Haas and colleagues to coin the term rhabdoid tumor of the kidney in 1981, Haas et al..

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