Marine Collagen-Based Bioink for 3D Bioprinting of a Bilayered Skin Model

Abstract

Marine organisms (i.e., fish, jellyfish, sponges or seaweeds) represent an abundant and eco-friendly source of collagen. Marine collagen, compared to mammalian collagen, can be easily extracted, is water-soluble, avoids transmissible diseases and owns anti-microbial activities. Recent studies have reported marine collagen as a suitable biomaterial for skin tissue regeneration. The aim of this work was to investigate, for the first time, marine collagen from basa fish skin for the development of a bioink for extrusion 3D bioprinting of a bilayered skin model. The bioinks were obtained by mixing semi-crosslinked alginate with 10 and 20 mg/mL of collagen. The bioinks were characterised by evaluating the printability in terms of homogeneity, spreading ratio, shape fidelity and rheological properties. Morphology, degradation rate, swelling properties and antibacterial activity were also evaluated. The alginate-based bioink containing 20 mg/mL of marine collagen was selected for 3D bioprinting of skin-like constructs with human fibroblasts and keratinocytes. The bioprinted constructs showed a homogeneous distribution of viable and proliferating cells at days 1, 7 and 14 of culture evaluated by qualitative (live/dead) and qualitative (XTT) assays, and histological (H&E) and gene expression analysis. In conclusion, marine collagen can be successfully used to formulate a bioink for 3D bioprinting. In particular, the obtained bioink can be printed in 3D structures and is able to support fibroblasts and keratinocytes viability and proliferation.

Fibrinogen-Based Bioink for Application in Skin Equivalent 3D Bioprinting

“…The biomaterial ink was semicrosslinked by mixing the fibrinogen-alginate solution with 100 mM CaCl 2 at volumetric ratios of 25:9 ( v / v ). The sterile formulation was obtained using alginate powder prepared according to a previously described protocol [ 21 ], sterile fibrinogen, and CaCl 2 and by performing all procedures under a laminar hood with sterile tools. The semicrosslinked biomaterial ink was centrifuged at 2500 RPM for 5 min to remove air bubbles.…”

“…The extrusion force, the biomaterial ink filament-like extrusion ability, and therefore the biomaterial ink homogeneity were assessed using a dedicated setup previously reported in [ 21 ]. Briefly, if a constant displacement rate is imposed on the syringe plunger, the uniformity of the loaded material would yield a constant extrusion force.…”

“…The rheological properties of fibrinogen-based biomaterial ink were evaluated through rotational tests (shear rate sweep) and oscillatory tests (amplitude sweep and frequency sweep), which were performed as previously described [ 21 ]. The rheological characterization was performed at 25 and 37 °C, considered as room temperature and physiological temperature, respectively.…”

“…Moreover, alginate is also FDA-approved for many biomedical applications and has been used in a number of clinical trials [ 20 ]. A stand-alone alginate solution can be printed but with poor resolution, while a semicrosslinked alginate solution obtained by adding Ca 2+ ions allows the increase in bioink viscosity and, therefore, the improvement of biofabricated structures’ printability [ 21 ].…”

Hydrogels in Cutaneous Wound Healing: Insights into Characterization, Properties, Formulation and Therapeutic Potential

“…The main source of commercially used collagen isolation is from marine sources [ 42 ], representing an abundant and environmentally friendly reservoir of collagen [ 64 ]. The process of obtaining collagen from the transformation of by-products of fish skin and scale is inexpensive and has minimal environmental impact [ 65 ].…”