Blue Light-Induced, Dosed Protein Expression of Active BDNF in Human Cells Using the Optogenetic CRY2/CIB System

Area of Science:

• Biotechnology
• Neuroscience
• Cell Therapy

Background:

• Optogenetic tools offer precise spatial and temporal control over gene and protein expression.
• This technology is promising for cell therapeutics, particularly in confined spaces like the inner ear.
• Enhancing neuronal survival and function is crucial for conditions like cochlear implantation.

Purpose of the Study:

• To utilize the CRY2/CIB optogenetic system to induce brain-derived neurotrophic factor (BDNF) transcription in human cells.
• To optimize transfection and illumination protocols for maximal protein expression.
• To establish the first optogenetic neurotrophic therapy for the inner ear.

Main Methods:

• Employed the blue light-activatable CRY2/CIB system for optogenetic control.
• Optimized transfection and illumination (LED/laser) protocols using luciferase reporter in HEK293 cells.
• Applied optimized protocols to induce BDNF production and tested its biological activity on spiral ganglion neurons.

Main Results:

• Achieved a 64.7-fold increase in BDNF expression upon light induction compared to basal levels.
• Demonstrated that light-induced BDNF is biologically active, promoting spiral ganglion neuron survival and neurite growth.
• Successfully transferred the optogenetic approach to autologous cell systems, including mesenchymal stem cells.

Conclusions:

• Optogenetic control of BDNF expression is a viable strategy for enhancing neuronal survival and function.
• This approach represents a novel optogenetic neurotrophic therapy for inner ear applications.
• The technology's adaptability to autologous cells broadens its therapeutic potential.