MUlti-sCale analysis of hUman Sputum: structure, rheology, transport – MUCUS

Chronic respiratory diseases represent a major public health issue in both industrialised and emerging countries. Objective and quantitative markers for their diagnosis and/or monitoring are, however, incomplete which prevents the development of efficient therapies. The LabCom project MUCUS (MUlti-sCale analysis of hUman Sputum), bringing together the Laboratoire Rhéologie et Procédés (LRP, CNRS/Grenoble INP/Univ. Grenoble-Alpes, UMR 5520) and Rheonova, focuses on the development of biophysical tools to fulfil this need.

Rheonova proposed and realised a first and functional device dedicated to the rheological analysis of sputum, clinically validated and commercialised since 2018. However, the correlation between mucus rheology and the clinical condition of patients remains essentially empirical. MUCUS is expected to shed new light on the mechanisms related to the existing biophysical markers, develop new biophysical markers, and improve the future clinical practices that will rely on these markers. The quadruple objective of the programme is (i) to validate the rheological approach, (ii) to define sample manipulation protocols, (iii) to refine and improve the relevant biomarkers, and (iv) to identify third therapeutic approaches to which rheology could be generalised. These objectives will respectively translate into four major research directions:

1. Understand, from in vitro models, the interactions between pathogens, structure, and transport properties of the mucus;

2. Quantify, from microstructural analyses, the impact of sample manipulations on the rheology of mucus and on the associated biomarkers;

3. Explore the rheology of mucus in regimes (large shear, high frequency) and at scales not exploited so far, and develop the associated instruments;

4. Understand the transport of agents (therapeutic vectors) within the mucus, and the transport of mucus within the lower airways.
These investigations should improve the use of devices currently offered by Rheonova and eventually to broaden its innovation portfolio towards new markets (point-of-care, then point-of-need devices) and other pathologies.