Single-Cell Transcriptomic Analysis Links Nonmyelinating Schwann Cells to Proinflammatory Response in the Lung

Area of Science:

• Immunology
• Cell Biology
• Pulmonary Medicine

Background:

• The lung's barrier function necessitates robust innate immunity against inhaled environmental factors.
• Schwann cells (SCs), including nonmyelinating Schwann cells (NMSCs), are present in the lung, but their role in lung physiology is largely unexplored.
• NMSCs are the predominant SC population within the lung.

Purpose of the Study:

• To identify and characterize Schwann cells within the lung.
• To investigate the potential role of pulmonary NMSCs in innate immunity and inflammation.
• To define the molecular profiles of lung SC subtypes.

Main Methods:

• Utilized a transgenic mouse model with tdTomato expression under the human glial fibrillary acidic protein promoter to visualize SCs.
• Performed single-cell transcriptomic analysis to identify distinct NMSC populations.
• Conducted in vitro LPS stimulation assays to assess chemokine and cytokine production by pulmonary SCs.
• Challenged mouse lungs with LPS to evaluate in vivo inflammatory responses.

Main Results:

• Identified two distinct NMSC populations in the lung: NMSC1 and NMSC2.
• Pulmonary SCs demonstrated the capacity to produce chemokines and cytokines following LPS stimulation in vitro.
• NMSC1 populations exhibited a significantly enriched proinflammatory response compared to other SC subtypes upon LPS challenge in vivo.
• Defined the molecular signatures of lung SCs, highlighting NMSC1's inflammatory potential.

Conclusions:

• Pulmonary NMSCs possess distinct molecular profiles and functional capacities.
• NMSC1 subtypes play a significant role in mediating inflammatory responses in the lung.
• These findings suggest a novel role for NMSCs in lung innate immunity and inflammation.