Insight into the Role of the Microbiome in Pulmonary tuberculosis in Kampala, Uganda
TMA2018CDF-2357
EDCTP2
Career Development Fellowship (CDF)
1. a) To examine the relationship between sputum and gut microbiome diversity and disease. b) To investigate the relationship between sputum and gut microbiome composition and treatment response in patients on first-line TB therapy, and whether dysbiosis resolves in patients who get cured from TB after successfully completing anti-TB therapy. 2. To investigate the relationship between sputum and gut microbiome composition and inflammatory cytokine production capacity.
Longitudinal study
The microbiota/microbiome, complex communities of microbes in mammals, play a significant role in health and disease including induction/function of the immune system. However, baseline information on their composition and potential role(s) in pulmonary tuberculosis (TB) in sub-Saharan Africa, is lacking. The overall purpose of this proposal is to determine the microbiome composition in pulmonary TB in Kampala Uganda, and examine its relationship with treatment- and immune-response in TB patients relative to their household healthy contacts without TB-infection and HIV-infection. In context of treatment naïve adult TB patients in Kampala Uganda, two specific aims are contingent to this goal; Specific Aims 1. a) To examine the relationship between sputum and gut microbiome diversity and disease. b) To investigate the relationship between sputum and gut microbiome composition and treatment response among patients on first-line TB therapy, and whether dysbiosis resolves in patients who get cured from TB after successfully completing anti-TB therapy. 2. To investigate the relationship between sputum and gut microbiome composition and inflammatory cytokine production capacity. Study design and approach This will be a longitudinal study nested in a concurrent MTI-project at Mulago National Referral Hospital in Kampala Uganda, which maintains a cohort of 320 Xpert-positive, treatment-naïve adult TB patients with followup at months 2, 5, 12, 18 and 24. We will investigate sputum, stool and blood samples from 160 participants (purposive sampling) at baseline (day 0) and months 2, 5, 12, 18 & 24 for microbial and cytokine profiles. Of the 160 participants, 100 will be pulmonary TB cases randomly selected from the parent MTI-cohort of whom 50 will be HIV-positive (TB+/HIV+) and 50 HIV-negative (TB+/HIV). Also, we will similarly investigate 60 household contacts as the comparator group (controls). Household contacts will be TB-negative family members of the 100 TB cases, of whom one half (30) will be HIV-positive without respiratory/pulmonary symptoms based on interferon-γ release assay (i.e. HIV+/TB- sub-group) while the other half (30) will be both HIV-negative and TBnegative i.e. the healthy contacts (HIV-/TB-). On achieving our aims, we will provide human microbiota profiles from a TB-endemic/HIV-burden setting, which profiles could be used as a reference for other settings in sub-Saharan Africa. Also, our data might reveal potential markers of TB-treatment response or failure. Such information is vital in devising novel region- or country-specific interventions.
Department | Institution | Country |
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Makerere University | UG |
Makerere University
Lecturer
A Thesis Submitted to the Directorate of Research and Graduate Training Makerere University, for the Award of the Degree of Doctor of Philosophy (Medical Molecular Microbiology) of Makerere University
http://dx.doi.org/10.1080/03079459994830
Information on microbiota dynamics in pulmonary tuberculosis (TB) in Africa is scarce. Here, we sequenced sputa from 120 treatment-naïve TB patients in Uganda, and investigated changes in microbiota of 30 patients with treatment-response follow-up samples. Overall, HIV-status and anti-TB treatment were associated with microbial structural and abundance changes. The predominant phyla were Bacteroidetes, Firmicutes, Proteobacteria, Fusobacteria and Actinobacteria, accounting for nearly 95% of the sputum microbiota composition; the predominant genera across time were Prevotella, Streptococcus, Veillonella, Haemophilus, Neisseria, Alloprevotella, Porphyromonas, Fusobacterium, Gemella, and Rothia. Treatment-response follow-up at month 2 was characterized by a reduction in abundance of Mycobacterium and Fretibacterium, and an increase in Ruminococcus and Peptococcus; month 5 was characterized by a reduction in Tannerella and Fusobacterium, and an increase in members of the family Neisseriaceae. The microbiota core comprised of 44 genera that were stable during treatment. Hierarchical clustering of this core’s abundance distinctly separated baseline (month 0) samples from treatment follow-up samples (months 2/5). We also observed a reduction in microbial diversity with 9.1% (CI 6–14%) of the structural variation attributed to HIV-status and anti-TB treatment. Our findings show discernible microbiota signals associated with treatment with potential to inform anti-TB treatment response monitoring.
PMID: 23109963 PMCID: PMC3469173
A dissertation submitted to the Directorate of Research and Graduate Training (Makerere University) for the award of the Degree of Master of Science in Molecular Biology of Makerere University