3D Tissue Printing to Cure Retinal Blindness

Camneil Daly

Tim Marschall

Ian Naval

Background - Causes of Blindness

• Retina has very organized and complex structure - difficult to repair
• Retinal cells:
• ganglion: nerve cells
• glial: support cells
• Blindness can be caused by cell degradation

Background - Neurites

• Neurites: projection from a neuron
• (eg. axon or dendrite)
• Microtubule bundles
• Growth stimulated by NGF, MAP1, and MAP2

Biology - How Cells are Prepared

• Glial cells obtained from tissue in adult male rats
• Cultured in growth medium (DMEM)
• Washed with calcium- and magnesium-free phosphate buffered saline, incubated for 5 minutes in Trypsin-EDTA
• To detach cells

Biology - How Cells are Prepared

• Ganglion cells: retinal tissue derived from adult male rats
• Prepared in B27 supplemented Neurobasal-A medium
• Passed through strainer to remove clumps of cells
• Cultured for five additional days at 37°C at 5% CO₂

Background - Inkjet Printers

• Two methods to print:
• Thermal inkjet
• Piezoelectric inkjet
• Problems:
• Requires very specific properties such as viscosity and surface tension (even without cells)

Biology - Experiment Methodology

• Scientists establish a design for the cells.
• The printer is cleaned with an alkaline cleaning solution.
• The group of prepared retinal cells, the bio ink, is added into the printer’s loading dock
• The bio ink is then dispensed from the printer onto separate plates.

Image of the printing apparatus

Biology - Experiment Results

• Printed cells compared with control cells:
• Viability not significantly affected
• Neurite outgrowth not affected
• Number of cells affected
• Importantly: printed glial cells retain their growth-promoting properties

J: control glia

K: printed glia

Biology - Experiment Problems

• Cells adhered to capillary wall near nozzles
• Initially thought neurite growth was affected by printing
• Overcome with future modifications

Commercialization Strategies

• Could make cell printing more efficient
• Less prone to clogging or losing cells
• Allows for inexpensive reconstructive retinal surgery

Prediction: Impact & Importance

• Impact on health: potential cures for retinal blindness, other health problems
• Impact on economy: creates new “cell” market

Ethical Implication

• Bioprinting can lead to man becoming “immortal” via replacing old organs and tissues with new ones.
• This can create a separation between those that can afford to extend their lives and those that cannot.

Sorcerer’s Stone from Harry Potter

Works Cited

• http://iopscience.iop.org/1758-5090/6/1/015001/pdf/1758-5090_6_1_015001.pdf
• http://www.sciencedaily.com/releases/2013/12/131218100227.htm
• More available on request

Questions?