Sensory neurons and osteoblasts: close partners in a microfluidic platform

Area of Science:

• Biomedical Engineering
• Neuroscience
• Cell Biology

Background:

• Nerve innervation is crucial for bone homeostasis and regeneration.
• Nerve fibers release soluble factors that influence bone cell activity.
• Understanding the neuro-osseous interface is vital for therapeutic development.

Purpose of the Study:

• To establish and characterize a coculture system of sensory neurons and osteoblasts.
• To mimic the in vivo bone microenvironment for studying neuro-osseous interactions.
• To investigate the crosstalk between the peripheral nervous system and bone cells.

Main Methods:

• Utilized compartmentalized microfluidic platforms for coculturing dorsal root ganglion (DRG) neurons and MC3T3-E1 osteoblasts.
• Employed morphological and functional tests, including immunocytochemistry and electron microscopy.
• Developed a semi-automated algorithm for reproducible image analysis of axonal outgrowth.

Main Results:

• Aligned microgrooves enhanced DRG adhesion and axonal outgrowth towards osteoblasts.
• Neurites in the osteoblastic compartment showed immunoreactivity for synapsin and calcitonin gene-related peptide.
• Axonal outgrowth was observed on various substrates, with collagen and laminin promoting greater outgrowth.

Conclusions:

• The developed coculture system effectively models in vivo neuro-osseous interactions.
• Specialized neuronal structures were identified at the interface with osteoblasts.
• This platform provides a valuable tool for studying the neuro-osseous system in diverse contexts.