Browsing by Author "Said-Hartley, Qonita"

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    Obstructive pulmonary disease in patients with previous tuberculosis : pathophysiology of a community-based cohort
    (Health & Medical Publishing Group, 2017) Allwood, Brian W.; Gillespie, Rencia; Galperin-Aizenberg, Maya; Bateman, Mary; Olckers, Helena; Taborda-Barata, Luis; Calligaro, Gregory L.; Said-Hartley, Qonita; Van Zyl-Smit, Richard; Cooper, Christopher B.; Van Rikxoort, Eva; Goldin, Jonathan; Beyers, Nulda; Bateman, Eric D.
    Background. An association between chronic airflow limitation (CAL) and a history of pulmonary tuberculosis (PTB) has been confirmed in epidemiological studies, but the mechanisms responsible for this association are unclear. It is debated whether CAL in this context should be viewed as chronic obstructive pulmonary disease (COPD) or a separate phenotype. Objective. To compare lung physiology and high-resolution computed tomography (HRCT) findings in subjects with CAL and evidence of previous (healed) PTB with those in subjects with smoking-related COPD without evidence of previous PTB. Methods. Subjects with CAL identified during a Burden of Obstructive Lung Disease (BOLD) study performed in South Africa were studied. Investigations included questionnaires, lung physiology (spirometry, body plethysmography and diffusing capacity) and quantitative HRCT scans to assess bronchial anatomy and the presence of emphysema (<–950 HU), gas trapping (<–860 HU) and fibrosis (>–200 HU). Findings in subjects with a past history and/or HRCT evidence of PTB were compared with those in subjects without these features. Results. One hundred and seven of 196 eligible subjects (54.6%) were enrolled, 104 performed physiology tests and 94 had an HRCT scan. Based on history and HRCT findings, subjects were categorised as no previous PTB (NPTB, n=31), probable previous PTB (n=33) or definite previous PTB (DPTB, n=39). Subjects with DPTB had a lower diffusing capacity (Δ=–17.7%; p=0.001) and inspiratory capacity (Δ=–21.5%; p=0.001) than NPTB subjects, and higher gas-trapping and fibrosis but not emphysema scores (Δ=+6.2% (p=0.021), +0.36% (p=0.017) and +3.5% (p=0.098), respectively). Conclusions. The mechanisms of CAL associated with previous PTB appear to differ from those in the more common smoking-related COPD and warrant further study.
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    Relationship of SARS-CoV-2–specific CD4 response to COVID-19 severity and impact of HIV-1 and tuberculosis coinfection
    (American Society for Clinical Investigation, 2021-05) Riou, Catherine; Du Bruyn, Elsa; Stek, Cari; Daroowala, Remy; Goliath, Rene T.; Abrahams, Fatima; Said-Hartley, Qonita
    T cells are involved in control of coronavirus disease 2019 (COVID-19), but limited knowledge is available on the relationship between antigen-specific T cell response and disease severity. Here, we used flow cytometry to assess the magnitude, function, and phenotype of SARS coronavirus 2–specific (SARS-CoV-2–specific) CD4+ T cells in 95 hospitalized COVID-19 patients, 38 of them being HIV-1 and/or tuberculosis (TB) coinfected, and 38 non–COVID-19 patients. We showed that SARSCoV- 2–specific CD4+ T cell attributes, rather than magnitude, were associated with disease severity, with severe disease being characterized by poor polyfunctional potential, reduced proliferation capacity, and enhanced HLA-DR expression. Moreover, HIV-1 and TB coinfection skewed the SARS-CoV-2 T cell response. HIV-1–mediated CD4+ T cell depletion associated with suboptimal T cell and humoral immune responses to SARS-CoV-2, and a decrease in the polyfunctional capacity of SARSCoV- 2–specific CD4+ T cells was observed in COVID-19 patients with active TB. Our results also revealed that COVID-19 patients displayed reduced frequency of Mycobacterium tuberculosis–specific CD4+ T cells, with possible implications for TB disease progression. These results corroborate the important role of SARS-CoV-2–specific T cells in COVID-19 pathogenesis and support the concept of altered T cell functions in patients with severe disease.