PROJECT SUMMARY
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), causes 1.6 million deaths per
mated to be infected with Mtb. There is an urgent need
to develop new treatment approaches. In this project, we aim to investigate the role of the host non-coding
RNA (ncRNA) landscape in driving susceptibility to tuberculosis (TB) across two study sites in Africa (Cape
Town, South Africa and Kampala, Uganda). Focusing on human primary macrophages, we plan to integrate,
using systems biology approaches, genetic architecture with the coding and non-coding gene expression
landscape of response to Mtb infection. We will identify response expression quantitative trait loci (ReQTLs)
for coding genes, long non-coding RNAs (lncRNAs), and microRNAs (miRNAs) which will be integrated with
coding/non-coding gene expression, co-expression, and deregulation networks to prioritize key variants and
regulators orchestrating macrophage response to Mtb infection. The most promising miRNAs and lncRNAs
will be validated with orthogonal techniques and considered for functionalization in human macrophages.
Here, we will employ loss-of function approaches using antisense oligonucleotides in ex vivo Mtb-infected
human monocyte-derived macrophages to evaluate the outcome on intracellular mycobacterial growth and
investigation of mechanistic macrophage-specific anti-mycobacterial effector functions. Targeting these
identified host miRNAs and lncRNAs could become promising candidates for adjunctive host-directed drug
therapy for TB.
Our central hypothesis is that a) Mtb hijacks host miRNAs and lncRNAs to establish successful
persistence and survival in macrophages, b) that human variation can affect key players and their roles, and
c) that an understanding of this can be leveraged to identify, design, implement, and test a novel RNA-based
anti-microbial treatment strategy. This hypothesis builds upon our previous unpublished and published data
[1] showing that Mtb targets miR-143, miR-365 and lincRNA-MIR99AHG in macrophages to promote
mycobacterial growth by fine-tuning expression levels of host genes and is supported by a growing number
of other studies [2-16]. Our long-term goal is to develop a host-directed drug system for antisense therapy,
specifically inhibiting miRNAs and lncRNAs that are crucially involved in TB pathogenesis. The rationale for
this approach would be to create a novel, targeted host-directed RNA-based drug therapy for TB. To achieve
this goal, we have assembled a team of experts in ncRNA biology, infectious disease, systems biology, and
bioinformatics from multiple sites in Southern Africa, Uganda and the USA.