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1.
bioRxiv ; 2023 May 08.
Article in English | MEDLINE | ID: mdl-37205594

ABSTRACT

Mechanisms by which HIV causes susceptibility to respiratory pathogens remain incompletely understood. We obtained whole blood and bronchoalveolar lavage (BAL) from people with latent TB infection in the presence or absence of antiretroviral-naïve HIV co-infection. Transcriptomic and flow cytometric analyses demonstrated HIV-associated cell proliferation plus type I interferon activity in blood and effector memory CD8 T-cells in BAL. Both compartments displayed reduced induction of CD8 T-cell-derived IL-17A in people with HIV, associated with elevated T-cell regulatory molecule expression. The data suggest that dysfunctional CD8 T-cell responses in uncontrolled HIV contribute to susceptibility to secondary bacterial infections, including tuberculosis.

2.
PLOS Glob Public Health ; 2(10): e0000800, 2022.
Article in English | MEDLINE | ID: mdl-36962607

ABSTRACT

BACKGROUND: There are limited data on the performance characteristics of ultrasound for the diagnosis of pulmonary tuberculosis in both HIV-positive and HIV-negative persons. The objective of this proof-of-concept study was to determine the sensitivity and specificity of ultrasound for the diagnosis of tuberculosis in adults. METHODS: Comprehensive thoracic and focused abdominal ultrasound examinations were performed by trained radiologists and pulmonologists on adults recruited from a community multimorbidity survey and a primary healthcare clinic in KwaZulu-Natal Province, South Africa. Sputum samples were systematically collected from all participants. Sensitivity and specificity of ultrasound to detect tuberculosis were calculated compared to a reference standard of i) bacteriologically-confirmed tuberculosis, and ii) either bacteriologically-confirmed or radiologic tuberculosis. RESULTS: Among 92 patients (53 [58%] male, mean age 41.9 [standard deviation 13.7] years, 49 [53%] HIV positive), 34 (37%) had bacteriologically-confirmed tuberculosis, 8 (9%) had radiologic tuberculosis with negative bacteriologic studies, and 50 (54%) had no evidence of active tuberculosis. Ultrasound abnormalities on either thoracic or abdominal exams were detected in 31 (91%) participants with bacteriologic tuberculosis and 27 (54%) of those without tuberculosis. Sensitivity and specificity of any ultrasound abnormality for bacteriologically-confirmed tuberculosis were 91% (95% confidence interval [CI] 76%-98%) and 46% (95% CI 32%-61%). Sensitivity and specificity of any ultrasound abnormality for either bacteriologically-confirmed or radiologic tuberculosis were 86% (95% CI 71%-95%) and 46% (95% CI 32%-61%). Overall performance did not appear to differ markedly between participants with and without HIV. CONCLUSION: A comprehensive ultrasound scanning protocol in adults in a high TB burden setting had high sensitivity but low specificity to identify bacteriologically-confirmed tuberculosis.

3.
Front Immunol ; 12: 631410, 2021.
Article in English | MEDLINE | ID: mdl-33897687

ABSTRACT

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.


Subject(s)
Gene Expression Profiling , HIV Infections/immunology , Histocompatibility Antigens Class I/immunology , Lung/cytology , Minor Histocompatibility Antigens/immunology , Mucosal-Associated Invariant T Cells/immunology , Respiratory Mucosa/cytology , Respiratory Mucosa/immunology , Adult , Female , HIV Infections/microbiology , Humans , Immunity, Mucosal , Latent Tuberculosis/immunology , Lung/immunology , Lung/virology , Male , Middle Aged , Mucosal-Associated Invariant T Cells/classification , Mucous Membrane/cytology , Mucous Membrane/immunology , Phenotype , Transcriptome , Young Adult
4.
J Child Adolesc Trauma ; 13(4): 419-427, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33269042

ABSTRACT

Child welfare systems in the Caribbean tend not to take multi-type maltreatment into account when assessing and treating victims of child maltreatment. This study aimed to provide evidence of the prevalence of multi-type maltreatment and patterns of co-occurrence of child abuse and neglect among children and adolescents in community residences across Trinidad. One hundred and two children and adolescents completed the Childhood Trauma Questionnaire which captured five abuse and neglect types: emotional abuse, physical abuse, sexual abuse, physical neglect and emotional neglect. The correlation analyses revealed significant positive relationships among the three types of abuse and a moderate positive correlation between the two types of neglect. T-test results indicated that girls were more likely than boys to experience physical abuse, emotional abuse and sexual abuse, however boys also reported high levels of abuse and neglect. The findings suggest that children are likely to face multiple forms of abuse and neglect that may contribute to its alarming severity and chronicity. Children in community residences are a population of particular interest given that residential care may be considered either a risk or a protective factor depending on the quality of care provided. Recommendations for future research and intervention strategies are proposed.

5.
Front Immunol ; 11: 864, 2020.
Article in English | MEDLINE | ID: mdl-32508817

ABSTRACT

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.


Subject(s)
Gene Expression Profiling , HIV Infections/immunology , Inflammation/genetics , Leukocytes, Mononuclear/immunology , Pulmonary Alveoli/immunology , Adolescent , Adult , Bronchoalveolar Lavage , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cohort Studies , Female , Granzymes/genetics , Humans , Inflammation/virology , Interferon-gamma/genetics , Leukocytes, Mononuclear/virology , Lymphocyte Activation , Male , Middle Aged , Pulmonary Alveoli/virology , Young Adult
6.
Invest Ophthalmol Vis Sci ; 54(5): 3798-805, 2013 May 31.
Article in English | MEDLINE | ID: mdl-23661371

ABSTRACT

PURPOSE: To determine the prevalence of binocular vision (BV) and eye movement disorders in a clinic population of older adults. METHODS: Retrospective clinic data were abstracted from files of 500 older patients seen at the University of Waterloo Optometry Clinic over a 1-year period. Stratified sampling gave equal numbers of patients in the 60 to 69, 70 to 79, and 80+ age groups. Data included age, general and ocular history and symptoms, use of antidepressants, a habit of smoking, refraction, visual acuity, BV and eye movement status for the most recent full oculo-visual assessment, and an assessment 10 years prior. The prevalence of any BV or eye movement abnormal test (AT) result, defined as a test result outside the normal range, was determined. This included strabismus (any) or phoria; incomitancy; poor pursuits; and remote near point of convergence (NPC). The prevalence of significant BV disorders (diagnostic entities, i.e., a clinical condition that may need treatment and may have functional implications) was also determined. RESULTS: The prevalence of any BV or eye movement at was 41%, 44%, and 51% in the 60 to 69, 70 to 79, and 80+ age groups, respectively. These figures were lower for 10 years earlier: 31%, 36%, and 40% for ages 50 to 59, 60 to 69, and 70+, respectively. The prevalence of any BV or eye movement disorder was 27%, 30%, and 38% for the three age groups and 17%, 19%, and 24% for 10 years prior. Age and use of antidepressants most commonly predicted BV or eye movement AT or disorder. CONCLUSIONS: BV disorders are common among older adults.


Subject(s)
Aging/physiology , Eye Movements/physiology , Ocular Motility Disorders/epidemiology , Vision Disorders/epidemiology , Vision, Binocular/physiology , Aged , Aged, 80 and over , Antidepressive Agents/therapeutic use , Canada/epidemiology , Female , Humans , Male , Middle Aged , Ocular Motility Disorders/physiopathology , Prevalence , Refraction, Ocular/physiology , Retrospective Studies , Risk Factors , Smoking/epidemiology , Vision Disorders/physiopathology , Visual Acuity/physiology
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