Lung-mimicking 3-Dimensional hydrogel culture system recapitulates key tuberculosis phenotypes and demonstrates pyrazinamide efficacy

Abstract

Faithful mimics of tuberculosis (TB) infection are warranted needed to providefor mechanistic insights into the complex host-pathogen interactions and for accelerating drug discovery. The current in vitro models provide a short duration to investigate the biology of this slow-growing pathogen, present divergent transcriptional signatures to human infections, and are unreliable drug discovery platforms. We developed and characterized a 3D collagen culture system mimicking the lung microenvironment (collagen fibres, pore size and stiffness), where we incorporated Mycobacterium tuberculosis (Mtb) infected THP-1 or primary monocytes. Dual RNA-sequencing revealed high similarity with human infections. Phenotypes observed in humans infection, such as foamy macrophages and mycobacterial cords (never seen in any other in vitro culture system), were reproduced in our culture system. The system overcomes many challenges associated with the traditional platforms for studying Mtb infections, including showing remarkable efficacy with clinically relevant concentrations of first-line anti-TB drug pyrazinamide, not seen in any other in vitro model, making it reliable, readily adoptable for tuberculosis studies and drug screening.

A bovine pulmosphere model and multiomics analyses identify a signature of early host response toMycobacterium tuberculosisinfection

“…This finding underlines the intricate and multifaceted nature of the host response to M. tuberculosis infection when compared with the avirulent M. bovis BCG-induced response. Additionally, a comparison with the publicly available transcriptome data from a variety of M. tuberculosis infection models employed by several previous studies revealed that the number of DEGs in our 3D pulmosphere model was notably higher following M. tuberculosis infection ( Fig 4C ) [8, 30–34]. This finding highlights the 3D pulmosphere as a more robust system compared to the single-cell, or PBMC-based models representing an enormous depth of complexity and cellular responses induced during M. tuberculosis infection.…”