Optic nerve regeneration in the mouse is a complex trait modulated by genetic background

Area of Science:

• Neuroscience
• Genetics
• Regenerative Medicine

Background:

• Optic nerve injury is a significant cause of vision loss.
• Understanding genetic factors influencing optic nerve regeneration is crucial for developing effective therapies.

Purpose of the Study:

• To investigate the role of genetic background in optic nerve regeneration.
• To compare regenerative capacity across different mouse strains.

Main Methods:

• Optic nerve crush (ONC) model in C57BL/6J, DBA/2J, and seven BXD recombinant inbred mouse strains.
• Knockdown of Pten in retinal ganglion cells using adeno-associated virus (AAV) delivery.
• Induction of mild inflammation and assessment of axonal regeneration at 0.5 mm and 1 mm from the crush site.

Main Results:

• Significant differences in axonal regeneration were observed among BXD strains and parental strains.
• BXD29 mice showed the highest regenerative capacity, with 759.8±79.2 axons at 0.5 mm from the crush site.
• Axon travel distance varied significantly, with BXD29 mice exhibiting the longest regeneration distance (2025.5±223.3 µm).

Conclusions:

• Genetic background profoundly influences optic nerve axonal regeneration.
• Differences in genetic makeup can lead to a threefold increase in regenerating axons and a 2.5-fold increase in regeneration distance.