Pericytes require physiological oxygen tension to maintain phenotypic fidelity

Area of Science:

• Cell Biology
• Tissue Engineering
• Physiology

Background:

• Pericytes are crucial for tissue homeostasis and endothelial barrier function.
• Pericyte dysfunction is linked to pathologies and cancer progression.
• Existing model systems do not accurately reflect in vivo pericyte biology, hindering research.

Purpose of the Study:

• To develop a robust protocol for isolating and culturing murine pericytes from lung, brain, bone, and liver.
• To establish culture conditions that maintain pericyte phenotype and function ex vivo.
• To create a model system for studying pericyte roles in both physiological and pathological contexts.

Main Methods:

• Isolation and culture of primary murine pericytes from multiple organs.
• Optimization of culture conditions, including controlled oxygen tension (10% O2 for lung; 5% O2 for brain, bone, liver).
• Assessment of pericyte phenotype via transcriptional and protein markers, functional tube formation assays, and manipulation of Klf4 expression.

Main Results:

• Established a protocol for culturing murine pericytes from lung, brain, bone, and liver, maintaining their phenotypes and functions.
• Demonstrated that controlled oxygen tension culture conditions improve ex vivo pericyte expansion and phenotype stability.
• Identified conditions to limit Klf4 expression, preventing spontaneous phenotypic switching, and successfully induced pathological switching in response to metastatic stimuli.

Conclusions:

• A robust method for studying pericyte biology in both physiological and disease states has been developed.
• The optimized culture conditions support ex vivo expansion while preserving pericyte phenotype and function.
• This model system enables accurate recapitulation of in vivo pericyte behavior, including pathological switching.