Isolation of primary odontoblasts: Expectations and limitations

Area of Science:

• Dental research
• Cell biology
• Tissue engineering

Background:

• Odontoblasts are crucial for dentin formation and regeneration.
• Efficient isolation of mature odontoblasts is essential for studying their biology and therapeutic potential.
• Current isolation protocols require optimization for cell yield and process integrity.

Purpose of the Study:

• To evaluate enzymatic treatment protocols for isolating mature odontoblasts.
• To assess the viability and process integrity of isolated odontoblasts.
• To identify specific genes for distinguishing odontoblasts from dental pulp fibroblasts.

Main Methods:

• Human molars were used to obtain primary odontoblasts.
• Enzymatic digestion with collagenase combined with protease, trypsin, or hyaluronidase.
• Histology and scanning electron microscopy for morphological assessment.
• Trypan blue staining for cell viability assessment.
• Gene expression analysis using real-time semi-quantitative PCR.

Main Results:

• Collagenase with protease yielded the highest cell numbers and best odontoblast process integrity.
• Combinations with hyaluronidase or trypsin resulted in truncated processes and cell detachment.
• Isolated odontoblasts showed poor viability after 24 hours in culture.
• Gene expression analysis ex vivo identified increased collagen, nestin, bone sialoprotein, and dentin matrix acidic phosphoprotein 1 in the odontoblast layer.

Conclusions:

• Collagenase and protease combination is optimal for isolating mature odontoblasts with intact processes.
• Primary odontoblasts isolated using this method are not suitable for extended in vitro culture.
• Identified genes can serve as markers to differentiate odontoblasts from pulp fibroblasts, aiding future research.