Rapid 3D Bioprinting of Multicellular Model Recapitulating Pterygium Microenvironment

Pterygium is an ocular surface disorder with high prevalence that can lead to vision impairment. As a pathological outgrowth of conjunctiva, pterygium involves neovascularization and chronic inflammation, but its pathogenesis remains largely unknown. Over the last decade, various types of disease models have been built to study pterygium. Here, we developed a 3D multicellular in vitro pterygium model using the digital light processing (DLP)-based 3D bioprinting of human conjunctival stem cells (hCjSCs). A novel feeder-free culture system was adopted and efficiently expanded the primary hCjSCs with homogeneity, stemness and differentiation potency. The DLP-based 3D bioprinting was able to fabricate hydrogel scaffolds that support the viability and biological integrity of the encapsulated hCjSCs. The bioprinted 3D pterygium model was fabricated with hCjSCs, immune cells and vascular cells to recapitulate the disease microenvironment. Transcriptomic analysis using RNA sequencing (RNA-seq) identified a distinct profile correlated to inflammation response, angiogenesis, and epithelial mesenchymal transition in the bioprinted 3D pterygium model. In addition, the pterygium signatures and disease relevance of the bioprinted model were validated with the public RNA-seq data from patient-derived pterygium tissues. By integrating the stem cell technology and 3D bioprinting, this is the first reported 3D in vitro disease model for pterygium that can be utilized by future studies towards the personalized medicine and the drug screening. Overall design: RNA seq was carried out on the 3D Bioprinting of Multicellular Model and 2D culture as control