5-Laser Spectral Flow Cytometer

• Subject Area: Microbiology, Virology and Immunology
• Term: Funded in 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 525502515

We apply for a spectral flow cytometer to perform high-parametric analysis of immune cells and extracellular vesicles. The spectral flow cytometer applied for here is intended to complement already existing flow cytometers at the Institute of Molecular Immunology and to meet the need of the scientists to perform experiments with a spectral flow cytometer. Spectral flow cytometry in our experiments over the last years was indispensable for analysis of immune cell populations isolated from peripheral organs such as the liver where they acquire a very high autofluorescence, which can be best compensated for by using spectral flow cytometry. Furthermore, studying rare immune cell populations such as antigen-specific CD8 T cells in the context of chronic viral infection of the liver or in cancer tissue requires high parametric analysis to achieve in depth phenotypic and functional characterization of the few cells available for analysis. Over the last years, we have used spectral flow cytometry to identify (1) a novel inhibitory metabolite produced by myeloid-derived suppressor cells that leads to complete metabolic shut-off of T cells within tumor tissue (Baumann et al. Nature Immunology 2020), (2) a novel form of metabolite-induced T cell activation through purinergic receptors that determines liver pathology in fatty liver disease, (3) a role of dendritic cells in the gut to mediate inflammation and cause inflammatory bowel disease, (4) a so far unknown dendritic cell subpopulation that activates T cells within tumor stroma to elicit protective anti-cancer immunity, (5) a liver tissue rheostat that shuts off T cells from activation and (6) to develop a technique based on spectral flow cytometry how to analyse single exosomes, which allows to trace exosomes from individual cells such as cancer cells and SARS-Cov-2 infected cells in patients. It is planned to use the spectral flow cytometer applied for here for the expansion of our capacity to use spectral flow cytometry to perform high-parametric phenotypic and functional characterization of rare immune cell populations from peripheral tissues. A second spectral flow cytometer is urgently needed because the existing spectral flow cytometer at the Institute of Molecular Immunology, that has been obtained more than 6 years ago, does not meet any more the demands from scientists at the institute working in third-party funded projects, although this instrument is used every day from 8 am to 10 pm. Furthermore, the increased capacity of the spectral flow cytometer applied for here to characterize small-sized vesicles will be key to characterize single exosomes and their surface phenotype in preclinical disease models and patient blood.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: 5-Laser Spektrales Durchflusszytometer
• Instrumentation Group: 3500 Zellzähl- und Klassiergeräte (außer Blutanalyse), Koloniezähler
• Applicant Institution: Technische Universität München (TUM)
• Leader: Professor Dr. Percy Alexander Knolle