Plasma-Based Bioinks for Extrusion Bioprinting of Advanced Dressings

Abstract

Extrusion bioprinting based on the development of novel bioinks offers the possibility of manufacturing clinically useful tools for wound management. In this study, we show the rheological properties and printability outcomes of two advanced dressings based on platelet-rich plasma (PRP) and platelet-poor plasma (PPP) blended with alginate and loaded with dermal fibroblasts. Measurements taken at 1 h, 4 days, and 18 days showed that both the PRP- and PPP-based dressings retain plasma and platelet proteins, which led to the upregulation of angiogenic and immunomodulatory proteins by embedded fibroblasts (e.g., an up to 69-fold increase in vascular endothelial growth factor (VEGF), an up to 188-fold increase in monocyte chemotactic protein 1 (MCP-1), and an up to 456-fold increase in hepatocyte growth factor (HGF) 18 days after printing). Conditioned media harvested from both PRP and PPP constructs stimulated the proliferation of human umbilical vein endothelial cells (HUVECs), whereas only those from PRP dressings stimulated HUVEC migration, which correlated with the VEGF/MCP-1 and VEGF/HGF ratios. Similarly, the advanced dressings increased the level of interleukin-8 and led to a four-fold change in the level of extracellular matrix protein 1. These findings suggest that careful selection of plasma formulations to fabricate wound dressings can enable regulation of the molecular composition of the microenvironment, as well as paracrine interactions, thereby improving the clinical potential of dressings and providing the possibility to tailor each composition to specific wound types and healing stages.

Wound-Microenvironment Engineering through Advanced-Dressing Bioprinting

“…We formulated two modalities of smart bioink, which meet the requirements for extrusion bioprinting, by blending pDAM2 with two different formulations of plasma ink (PPP/ALG and PRP/ALG). The latter mimic the pool of soluble factors present in the wound, as previously reported [ 23 ], thereby adding further functionalities to the pDAM2 bioink component and favoring fibroblast functions. As shown, both hydrogel composites showed good cell compatibility with dermal fibroblasts and supported their biological paracrine functions.…”

“…Following the methodology described before [ 23 ], proper 3D-printing resolution and dispensing uniformity were achieved with both pDAM2:PRP/ALG and pDAM2:PPP/ALG bioinks, obtaining advanced wound dressings with high reproducibility. This was due to filament uniformity during extrusion and maintenance of the construct stability with 100% infill.…”

“…Adding to bioink advancements for extrusion bioprinting, we blended two natural hydrogels, sharing a common crosslinking mechanism for the post-printing stability of the construct. We used, firstly, decellularized extracellular matrix from porcine adipose tissue and, secondly, a previously developed plasma bioink with two different platelet concentrations [ 23 ]. Adipose tissue has high potential as an abundant source of ECM to prepare biomaterials designed for the growth, differentiation and preservation of different cell phenotypes [ 29 , 30 ].…”

“…In recent years, two different plasma formulations have been used to functionalize biomaterials for tissue engineering [ 23 , 48 , 49 , 50 ], specifically, PRP and PPP, equivalent to freeze-frozen plasma (FFP) in transfusion medicine. Cubo et al pioneered the use of PPP as a bioink component for skin repair.…”

“…Five-milliliter syringes loaded with the composite bioinks were incubated at 37 °C for 10 min before printing. Regarding the printability of the bioinks, this was previously evaluated independently for each hydrogel-based ink, as well as for the blend, following the protocol described by Del Amo et al (2021) [ 23 ]. The optimization of the extrusion parameters included the nozzle selection and the definition of the layer height (0.4 mm), as well as the total number of layers (2) in the constructs.…”