Filippo Renò

Since the biobanks’ inception in 1980, millions of human biological samples have been stored worldwide for medical research or treatment purposes. Today the secondary use of biobanks plays an increasingly important role in research projects because it allows large-scale research starting from professional collections of biospecimens and related clinical data. It would be limiting, in the “-omics” era, to not consider the enormous potential value to law enforcement of these biospecimens, where the availability of high-performance techniques makes it possible to obtain a large amount of data, even within a single session. Therefore, the quality of the sample, in addition to the associated clinical information, becomes of crucial importance to derive scientifically valid information, including for forensic research purposes. Proposing the introduction of the concept of “solidarity”, traditionally applied only to medical and research biobanks, led to public commitment to forensic medicine. Granting the forensic researcher this possibility certainly raises some questions regarding regulatory and ethical aspects of consent, privacy, confidentiality, transparency, and participant/donor trust. Since the debate has not stopped since the origin of biobanks, this review aims to explore the state of the art relating to the use of human biological material in medical biobanks for biomedical and forensic research.

Background: Gelatin–xanthan gum (Gel–Xnt) hydrogel has been previously modified to improve its printability; now, to increase its ability for use as cell-laden 3D scaffolds (bioink), polydopamine (PDA), a biocompatible, antibacterial, adhesive, and antioxidant mussel-inspired biopolymer, has been added (1–3% v/v) to hydrogel. Methods: Control (CT) and PDA-blended hydrogels were used to print 1 cm2 grids. The hydrogels’ printability, moisture, swelling, hydrolysis, and porosity were tested after glutaraldehyde (GTA) crosslinking, while biocompatibility was tested using primary human-derived skin fibroblasts and spontaneously immortalized human keratinocytes (HaCaT). Keratinocyte or fibroblast suspension (100 µL, 2.5 × 105 cells) was combined with an uncrosslinked CT and PDA blended hydrogel to fabricate cylinders (0.5 cm high, 1 cm wide). These cylinders were then cross-linked and incubated for 1, 3, 7, 14, and 21 days. The presence of cells within various hydrogels was assessed using optical microscopy. Results and discussion: PDA blending did not modify the hydrogel printability or physiochemical characteristics, suggesting that PDA did not interfere with GTA crosslinking. On the other hand, PDA presence strongly accelerated and increased both fibroblast and keratinocyte growth inside. This effect seemed to be linked to the adhesive abilities of PDA, which improve cell adhesion and, in turn, proliferation. Conclusions: The simple PDA blending method described could help in obtaining a new bioink for the development of innovative 3D-printed wound dressings.

The lymphatic system is of fundamental importance in maintaining a fluid balance in the body and tissue homeostasis; it drains protein-rich lymph from the interstitial space and facilitates the release of cells that mediate the immune response. When one tissue is damaged, more cells and tissues work to repair the damaged site. Blood and lymph vessels are particularly important for tissue regeneration and healing. Angiogenesis is the process of the formation of new blood vessels and is induced by angiogenic factors such as VEGF-A; VEGF-C/D-induced lymphangiogenesis and both occur simultaneously during wound healing. After the inflammatory phase, lymphatic vessels suppress inflammation by aiding in the drainage of inflammatory mediators; thus, disorders of the lymphatic system often result in chronic and disabling conditions. It has recently been clarified that delayed wound healing, as in diabetes, can occur as a consequence of impaired lymphangiogenesis. In this review, we have highlighted recent advances in understanding the biology underlying lymphangiogenesis and its key role in wound healing, and the possibility of its pharmacological modulation as a novel therapeutic strategy for the treatment of chronic wounds.