Protocol to annotate dendritic cell maturation types in vivo making use of lipid nanoparticle-based approaches

The current panels used to annotate mature dendritic cells (DCs) by flow cytometry do not suffice to deconvolute homeostatic from immunogenic mature DCs. Here, we present a protocol to classify DCs along a homeostatic/immunogenic spectrum making use of flow cytometry and/or transcriptional profiling. We describe steps to steer DC maturation in vivo using a lipid nanoparticle (LNP)-based approach. We detail procedures to formulate, characterize, and generate these LNPs and outline their application in mice. For complete details on the use and execution of this protocol, please refer to Rennen et al. 1 • Instructions for the formulation of empty or cargo-loaded lipid nanoparticles (LNPs) • In vivo assays to measure LNP immunogenicity • Flow cytometry panels to evaluate dendritic cell maturation • Transcriptional profiling assays to characterize dendritic cell maturation states Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics. The current panels used to annotate mature dendritic cells (DCs) by flow cytometry do not suffice to deconvolute homeostatic from immunogenic mature DCs. Here, we present a protocol to classify DCs along a homeostatic/immunogenic spectrum making use of flow cytometry and/or transcriptional profiling. We describe steps to steer DC maturation in vivo using a lipid nanoparticle (LNP)-based approach. We detail procedures to formulate, characterize, and generate these LNPs and outline their application in mice.