Assistant Professor University of California Riverside, United States
Introduction: Corneal blindness is increasingly prevalent on a global scale. Donor tissues remain the primary treatment, however, less than 190,000 transplants are performed worldwide due to shortage of transplantable corneas; waiting-list data show that ~12.7 million people are awaiting transplantations.(1) A bioengineered cornea would represent an alternative supply; however, the unique biochemical and structural makeup of the cornea has hindered development. This research develops a bioengineered corneal equivalent (BCE) as a first step to providing a transplantable tissue supply.
Materials and
Methods: Primary human Corneal Keratocytes (hCKs) were cultured for 5 weeks to produce cell derived matrix (CDM). CDM was decellularized, lyophilized, digested and neutralized (~1.8 mg/mL) to enrich an AGC-10 Matrix (Aspect Biosystems). AGC-10 Matrix is a two-part bioink material containing 1.5% w/w alginate in Part A and 3.2 mg/mL collagen in Part B. Approximately ~3.2 million CKs were encapsulated in each printed cornea. The BCE was bio-printed using an RX1 Aspect Biosystems 3D-BioPrinter with a calcium chloride crosslinker solution (Aspect Biosystems) , matured for 3-5 weeks in culture and post processed using plastic compression. Physiologically relevant cellular organization was characterized using custom MATLAB scripts of confocal images. Live dead viability assays were conducted directly after printing and after ex-vivo transplantation.
Results, Conclusions, and Discussions: Results and
Discussion: We demonstrate a physiologically relevant BCE with (1) a highly organized collagen matrix; (2) a viable population of CKs; and (3) the unique mix of collagen and GAGs required for spacing. Print patterns are designed with linear layers orthogonal to each other mimicking the corneal lamellae. Interleaved spiral cell-laden layers exhibit the corkscrew pattern of native cornea.
Conclusions: The primary contribution of this work is a novel demonstration of tissue specific CDH and its application in a tissue engineered cornea. As a general tool for research or translational use, tissue specific CDH will broadly impact many biomedical fields, especially in the development of biomimetic models. These advancements represent early steps to increased accessibility for 3D-BioPrinted Tissue Models.
Acknowledgements (Optional): (1) Gain et al., “Global Survey of Corneal Transplantation and Eye Banking.”
