Project Details
Projekt
Single‐cell level phenotyping of multicellular dynamics in the DRG during pain resolution
Subject Area
Molecular and Cellular Neurology and Neuropathology
Anaesthesiology
Anaesthesiology
Term
since 2025
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 426503586
In this project, we aim to identify molecular and cellular phenotypes and mechanisms of natural pain resolution. In the first funding period, we have used chronic constriction injury (CCI) of the sciatic nerve to model natural pain resolution in rats, in both sexes. The data show injury- and pain resolution-related phenotypes which are multicellular, multifactorial, and sex-specific. Most striking was the identification of a macrophage subtype, which ‘displaces’ satellite glial cells (SGC) from the sensory neuron border after injury, and which exits the neuron/SGC interface during pain resolution. We hypothesize that specific phenotypes of local macrophages and SGC develop during pain resolution. Moreover, we think that there is a biological connection to monocytes/macrophages in the blood of rats and patients. In our working program, we can build on our already existing RNA-Seq data to better define the neuron-near macrophage phenotype with immunofluorescence labelling. Moreover, we will localize the cellular origin of signalling mediators regulated during pain resolution (RNAscope). Next, we will develop a strategy to isolate local SGC and macrophages, from the DRG, during pain resolution, in both sexes. The cells will be categorized with flow cytometry and subsequent mini-bulk and single cell RNA-Seq. Changes in macrophage clusters (or trajectories) will help to focus on monocytes/macrophages in the blood of the CCI rats and in patients suffering from Chronic Regional Pain Syndrome (CRPS) with and without pain resolution. The complex datasets (multi-parametric flow cytometry, bioimages, RNA-Seq) will be analysed and integrated. To investigate the dynamics of macrophages, we will culture neuron/SGC-units in 3D, in biocompatible, printable scaffolds. We aim to investigate how macrophages are attracted into the neuron/SGC interface. If we succeed, we will have the unique option to investigate, on a causal level, how neuron/SGC units attract macrophages and how neuronal excitability and signal mediators (e.g. Ccl2, Csf1) coordinate this biological process. We expect to find specific biological processes and signalling checkpoints involved in pain resolution.
DFG Programme
Clinical Research Units
