A novel mycobacterial growth inhibition assay employing live-cell imaging of virulent M. tuberculosis and monitoring of host cell viabilityShow others and affiliations
2020 (English)In: Tuberculosis, ISSN 1472-9792, E-ISSN 1873-281X, Vol. 124, article id 101977Article in journal (Refereed) Published
Abstract [en]
Our aim was to develop a Mycobacterium tuberculosis (Mtb) growth inhibition assay (MGIA) as a summary estimate of host immune control of virulent Mtb. Mycobacterial growth inhibition (MGI) using previously frozen human PBMCs infected with H37Rv was assessed by live-cell imaging (Incucyte (c)) complemented by imaging flow cytometry analysis of phagocytosis. MGI measured as relative fluorescence units (RFU) was calibrated to time to positive culture (TTP) in BACTEC 960 MGIT. At a MOI (multiplicity of infection) of 5, there was a wide range of MGI of blood donors (1.1*10(6)-2.7*10(6) RFU, n = 14). Intra- and inter-assay variability were at most 17.5 and 20.7 CV%. Cell viability at day 5 was 57 and 62% monitored by the LDH and Draq7 assays respectively. There was a strong correlation between a readout for Mtb growth using CFU counts or TTP compared to RFU (r2 >= 0.96). Our MGIA enabling live-cell imaging and monitoring of cell viability was able to detect a wide range of Mtb growth inhibition by PBMCs and was calibrated to several readout options for bacterial growth. This MGIA may be valuable as a surrogate marker of host immunity in a personalized medicine approach.
Place, publisher, year, edition, pages
CHURCHILL LIVINGSTONE , 2020. Vol. 124, article id 101977
Keywords [en]
Tuberculosis; MGIA; Immune response; Live-cell imaging; PBMCs
National Category
Microbiology in the medical area
Identifiers
URN: urn:nbn:se:liu:diva-171006DOI: 10.1016/j.tube.2020.101977ISI: 000576462400009PubMedID: 32829078OAI: oai:DiVA.org:liu-171006DiVA, id: diva2:1485114
Note
Funding Agencies|Swedish Research CouncilSwedish Research Council; Swedish Heart-Lung FoundationSwedish Heart-Lung Foundation
2020-11-012020-11-012023-12-28