Sigryn —A safe and flexible cartridge for pathogen imaging

PI(s)/Head responsible for the resource:

Johan Elf

Host organisation(s):

Uppsala University

Resource description:

Direct imaging of individual bacteria responding to antibiotic exposure enables phenotypic antibiotic susceptibility testing (pAST) in less than one bacterial generation time. The microfluidic systems we have developed for this analysis have so far relied on external pressure control, which is not safe to operate with risk group 3 (RG3) bacteria. The systems are also highly instrument-dependent, which makes them expensive and inflexible.

To enable direct single-cell pAST for unknown pathogens up to and including RG3, we have invented a method for driving liquid in the microfluidics independently of the analyser instrument. This design enables complete containment of the bacterial sample, as the cartridge requires no external ports for operation. Consequently, the cartridge can be taken away from the instrument and incubated separately, such that the same imaging instrument can be used to analyse many samples in parallel. In this project, we will develop and build cartridges based on the new concept and begin evaluating AST performance in a BSL3 setting.

The cartridge will radically simplify advanced imaging of RG3 pathogens, since the additional glowbox needed to work with pneumatic systems in BSL3 can be avoided. In the case of a pandemic or war, the cartridge can be used to prioritise the use of scarce antibiotics and find effective antibiotics for weaponised pathogens. Under normal circumstances, the technology can be used for rapid pAST of high-risk pathogens such as Mycobacterium tuberculosis (M. tb) and nontuberculous mycobacteria.

Contact information:

Johan Elf
Cell and Molecular Biology, Uppsala University
Email: johan.elf@icm.uu.se