Capture and visualization of live Mycobacterium tuberculosis bacilli from tuberculosis bioaerosols

Dinkele, R.; Gessner, S.; Koch, A. S.; Morrow, C.; Gqada, M.; Kamariza, M.; Bertozzi, C.; Smith, B.; McLoud, C.; Kamholz, A.; Bryden, W.; Call, C.; Mizrahi, V.; Wood, R.; Warner, D. F.

doi:10.1101/2019.12.23.887729

bioRxiv · 10.1101/2019.12.23.887729

Capture and visualization of live Mycobacterium tuberculosis bacilli from tuberculosis bioaerosols

Dinkele, R.·Gessner, S.·Koch, A. S.·Morrow, C.·Gqada, M.·Kamariza, M.·Bertozzi, C.·Smith, B.·McLoud, C.·Kamholz, A.·Bryden, W.·Call, C.·Mizrahi, V.·Wood, R.·Warner, D. F.

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Abstract

The tuberculosis (TB) pandemic demands urgent interventions such as those designed to interrupt Mycobacterium tuberculosis (Mtb) transmission, a challenge exacerbated by our poor understanding of the events enabling successful transfer of infectious bacilli between hosts. To address this problem, we developed the Respiratory Aerosol Sampling Chamber (RASC), a personal clean-room equipped with high-efficiency filtration and sampling technologies that allow biosafe capture and isolation of particulate matter - including Mtb bacilli - released by patients during natural breathing and (non-induced) cough. Here, we demonstrate the use of DMN-trehalose labelling to detect and quantify live Mtb bacilli among complex bioaerosol samples arrayed in a bespoke nanowell device following capture in the RASC. A pilot study identified Mtb in more than 85 % of known TB patients, improving significantly on previous work which has relied on animal infection and cough sampling to estimate transmission events. Moreover, intra-patient comparisons of bioaerosol and sputum samples indicated that Mtb aerosols likely derive from a compartment other than sputum. These results support the utility of the RASC platform for research aimed at interrupting Mtb transmission, including the non-invasive detection of Mtb-infected individuals who are predicted to contribute to bacillary spread despite the absence of clinical symptoms.

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Dinkele, R., Gessner, S., Koch, A. S., Morrow, C., Gqada, M., Kamariza, M., Bertozzi, C., Smith, B., McLoud, C., Kamholz, A., Bryden, W., Call, C., Mizrahi, V., Wood, R., Warner, D. F.. 2019-12-27. Capture and visualization of live Mycobacterium tuberculosis bacilli from tuberculosis bioaerosols. https://doi.org/10.1101/2019.12.23.887729

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