Detection of lipid nanoparticles phagocytosed by antigen presenting cells using imaging flow cytometry
Year: 2024
Type: conference-abstract
Abstract: mRNA vaccines were critical for the prevention of severe disease during the COVID-19 pandemic and efficacy of their delivery was achieved through nucleic acid-encapsulated lipid nanoparticles (LNPs). Despite the effectivness of mRNA vaccines, the mechanisms by which antigen-presenting cells (APCs) recognize and phagocytose the LNP cargo are not fully understood. Here, we used the BD CellView™ Image Technology on the BD FACSDiscover™ S8 Cell Sorter to visualize LNPs phagocytosed by host cells. LNPs formulated with green fluorescent (DiO)-labeled lipids were injected intramuscularly into mice. With the imaging capabilities of the BD FACSDiscover™ S8 Cell Sorter, we visualized LNPs in different APCs and observed different morphology of LNPs in dendritic cell subsets and monocytes. A time course experiment uncovered the kinetics of antigen recognition upon LNP-mediated cargo delivery. Analysis using the instrument imaging parameters revealed unique cell clusters associated with distinct morphology of LNP phagocytosis. We then sorted the LNP+ cells and evaluated their transcriptomic signature by real-time PCR. This work provides a workflow to visualize LNP phagocytosis followed by image-based cell sorting for downstream characterization enabled by the BD FACSDiscover™ S8 Cell Sorter. With increased adoption of LNP-mediated nucleic acid vaccines, the image-based cell sorter provides a powerful tool to understand the host immune response upon vaccination.
Source: The Journal of Immunology
Institution: University of Pennsylvania
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W4404166514