An in vitro assessment of the responses of human dermal fibroblast seeded on 3D printed thermoplastic polyurethane scaffold

Abstract

Tissue engineering is a multidisciplinary field is an interdisciplinary field for the design of biological substitutes that can improve, restore, and maintain tissue functions. Thermoplastic polyurethanes (TPUs) are linear polymers which are widely used for tissue engineering due to its flexibility in processing methods, biocompatibility and excellent mechanical properties. They are suitable materials for use in three-dimensional (3D) printing. Dermal fibroblasts are mesenchymal cells which play crucial roles in physiological tissue repair. The present study aimed to investigate the viability, proliferation, adhesion, and type IV collagen expression of human dermal fibroblasts (HDFs) seeded on 3D printed TPU scaffolds in vitro. HDFs were seeded on 3D TPU scaffolds or tissue culture polystyrene plates as control and cultured for 1, 3, 7, and 14 days. 3D TPU scaffolds were prepared using a custom made fused deposition modelling printer. The viability and proliferation of cells was analyzed by WST-1 assay on days 1 and 3. The cell adhesion was evaluated by scanning electron microscopy (SEM) on days 1 and 3. The cell morphology was examined by hematoxylin and eosin (H&E) staining. Expression of type IV collagen was analyzed by immunohistochemical (IHC) staining. The viability of HDFs on 3D TPU scaffolds was lower than their control groups on days 1 and 3, slightly higher on day 3. SEM images showed HDF attachment to the 3D TPU scaffold surface with spindle-shaped morphology. H&E staining demonstrated that HDFs on 3D TPU scaffolds showed smaller morphologies on days 7 and 14 compared to days 1 and 3. Type IV collagen staining was more intense in HDFs on 3D TPU scaffolds on day 1, 3, and 7 compared to day 14. In conclusion, our study shows the biocompatibility and the potential applications of 3D printed TPU scaffolds for skin tissue engineering using fibroblasts.

Keywords

• TPU
• human dermal fibroblast
• scaffold

Öz

Doku mühendisliği, doku fonksiyonlarını iyileştirebilen, restore edebilen ve sürdürebilen biyolojik ikamelerin tasarımı çalışmalarını içeren multidisipliner bir alandır. Termoplastik poliüretanlar (TPU'lar), üretim yöntemlerindeki esneklikleri, biyouyumlulukları ve mükemmel mekanik özellikleri nedeniyle doku mühendisliğinde yaygın olarak kullanılan lineer polimerlerdir. Bu özellikleri ile üç boyutlu (3B) baskıda kullanıma uygun malzemelerdir. Dermal fibroblastlar (HDF), fizyolojik doku onarımında önemli rol oynayan mezenkimal hücrelerdir. Çalışmamızda, in vitro olarak 3B baskılı TPU doku iskelelerine ekilen insan HDF'lerin canlılığı, proliferasyonu, adezyonu ve tip IV kollajen ekspresyonunu araştırmayı amaçladık. HDF'ler, 3B TPU doku iskeleleri ve kontrol olarak doku kültürü polistiren plakaları üzerine ekildi ve 1, 3, 7 ve 14 gün boyunca kültüre edildi. 3B TPU doku iskeleleri, özel yapılmış bir eriyik yığma modelleme (FDM) yazıcısı kullanılarak hazırlandı. Hücrelerin canlılığı ve proliferasyonu, 1. ve 3. günlerde WST-1 testi ile analiz edildi. Hücre adezyonu, 1. ve 3. günlerde taramalı elektron mikroskobu (SEM) ile değerlendirildi. Hücre morfolojisi, hematoksilen ve eozin (H&E) boyaması ile incelendi. Tip IV kollajen ekspresyonu, immünohistokimyasal (IHC) boyama ile analiz edildi. HDF'lerin 3B TPU doku iskeleleri üzerindeki canlılığı, 1. ve 3. günlerde kontrol gruplarından daha düşük, 3. günde biraz daha yüksekti. H&E boyaması ile, 3B TPU doku iskelelerindeki HDF'lerin 1. ve 3. günlere kıyasla 7. ve 14. günlerde daha küçük morfolojiler gösterdiği tespit edildi. Tip IV kollajen boyaması, 3B TPU doku iskelelerindeki HDF'lerde 14. güne kıyasla 1., 3. ve 7. günlerde daha yoğundu. Sonuç olarak, çalışmamız, cilt dokusu mühendisliği için 3B baskılı TPU doku iskelelerinin fibroblastlar ile biyouyumluluğunu ve potansiyel uygulamalarını göstermektedir.

Anahtar Kelimeler

• TPU
• insan dermal fibroblast
• doku iskelesi

Kaynakça

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