Yin Hongbo, Wang Xiaokun, Majumdar Shoumyo, Sohn Jeeyeon, Kim Byung-Jin, Stark Walter, Elisseeff Jennifer H
Department of Ophthalmology, Sichuan University, Chengdu 610041, China.
Wilmer Eye Institute, Department of Ophthalmology, Johns Hopkins School of Medicine, Baltimore, MD 21231, USA.
Bioengineering (Basel). 2019 Sep 27;6(4):90. doi: 10.3390/bioengineering6040090.
To investigate the impact of tissue derived biological particles on enzyme-mediated weakened corneas. Rabbit corneas were treated with enzymes to create an ex vivo ectatic model that simulated representative characteristics of keratoconus (KC). Porcine cornea, cartilage, and lymph node tissues were processed to remove most cellular components and cryomilled into microparticles. The KC corneas were cultured in medium containing the tissue-derived biological particles (TDP) overnight. The mechanical, thermal, ultrastructural changes, and gene expressions of corneal stromal cells were characterized to evaluate the effects of the TDP treatment. The enzyme treatment significantly reduced corneal mechanics and thermal stability, and also disrupted the extracellular matrix ultrastructure. After culturing with TDP medium, the Young's modulus of the modeled KC corneas increased by ~50%, comparable to normal cornea controls. Similarly, the thermal denaturation temperature of the corneas was restored. These findings also corresponded to a significant increase in collagen fibril density after TDP treatment. Furthermore, corneas cultured in TDP medium significantly downregulated expression of the pro-inflammatory gene Tnfα, and restored the expression of the key keratocyte markers , , and . Tissue-derived biological particles reinforce mechanical and thermal properties of corneal tissue in an ex vivo model of KC. Through this study, we demonstrate and characterize the previously unexplored impact of tissue-derived biological scaffolds on corneal biomechanics, thermal stability, and gene expression, presenting a potential new therapy for ocular disease.
为研究组织源性生物颗粒对酶介导的弱化角膜的影响。用酶处理兔角膜以建立一种模拟圆锥角膜（KC）代表性特征的离体扩张模型。对猪角膜、软骨和淋巴结组织进行处理以去除大部分细胞成分，并冷冻研磨成微粒。将KC角膜在含有组织源性生物颗粒（TDP）的培养基中培养过夜。对角膜基质细胞的力学、热学、超微结构变化和基因表达进行表征，以评估TDP处理的效果。酶处理显著降低了角膜的力学性能和热稳定性，还破坏了细胞外基质超微结构。在用TDP培养基培养后，模拟的KC角膜的杨氏模量增加了约50%，与正常角膜对照相当。同样，角膜的热变性温度也恢复了。这些发现还对应于TDP处理后胶原纤维密度的显著增加。此外，在TDP培养基中培养的角膜显著下调了促炎基因Tnfα的表达，并恢复了关键角膜细胞标志物、和的表达。在KC的离体模型中，组织源性生物颗粒增强了角膜组织的力学和热学性能。通过这项研究，我们展示并表征了组织源性生物支架对角膜生物力学、热稳定性和基因表达的先前未探索的影响，为眼部疾病提供了一种潜在的新疗法。
