Acellular Fish Skin Grafts and Pig Urinary Bladder Matrix Assessed in the Collagen-Induced Arthritis Mouse Model.

It is vital that cellular- and tissue-based products (CTPs) used for wound treatment do not provoke autoimmunity. In this study, the immunogenic response to extracts of 2 CTPs of piscine and porcine origin was assessed in the collagen-induced arthritis model. Male DBA/1J mice were divided into 4 groups, each composed of 7 to 9 animals. Each animal was injected with one of following to assess their immune responses: (1) bovine type II collagen (100 µg) in Freund's adjuvant, (2) extract of piscine skin (100 µg) in Freund's adjuvant, (3) extract of porcine urinary bladder matrix (100 µg) in Freund's adjuvant, or (4) Freund's adjuvant alone (control) at the beginning of the experiment and 3 weeks later. Clinical signs of arthritis were assessed from week 5 onwards, and anti-type II and anti-type I collagen antibody immunoglobulin G (IgG) serum levels were measured before injections and 8 weeks after exposure using enzyme-linked immunosorbent assays. Only the mice exposed to bovine type II collagen developed clinical arthritis accompanied by very high anti-type II collagen IgG serum levels. Anti-type II collagen IgG serum levels were also detected in the porcine group but were undetectable in the piscine skin and control groups after 8 weeks. There were no significant differences in anti-type I collagen IgG serum levels among the groups. The results showed that piscine skin did not provoke systemic autoimmunity against type II collagens in DBA/1J mice.

Regenerative and Antibacterial Properties of Acellular Fish Skin Grafts and Human Amnion/Chorion Membrane: Implications for Tissue Preservation in Combat Casualty Care.

BACKGROUND: Improvised explosive devices and new directed energy weapons are changing warfare injuries from penetrating wounds to large surface area thermal and blast injuries. Acellular fish skin is used for tissue repair and during manufacturing subjected to gentle processing compared to biologic materials derived from mammals. This is due to the absence of viral and prion disease transmission risk, preserving natural structure and composition of the fish skin graft. OBJECTIVES: The aim of this study was to assess properties of acellular fish skin relevant for severe battlefield injuries and to compare those properties with those of dehydrated human amnion/chorion membrane. METHODS: We evaluated cell ingrowth capabilities of the biological materials with microscopy techniques. Bacterial barrier properties were tested with a 2-chamber model. RESULTS: The microstructure of the acellular fish skin is highly porous, whereas the microstructure of dehydrated human amnion/chorion membrane is mostly nonporous. The fish skin grafts show superior ability to support 3-dimensional ingrowth of cells compared to dehydrated human amnion/chorion membrane (p < 0.0001) and the fish skin is a bacterial barrier for 24 to 48 hours. CONCLUSION: The unique biomechanical properties of the acellular fish skin graft make it ideal to be used as a conformal cover for severe trauma and burn wounds in the battlefield.

[Decellularized fish skin: characteristics that support tissue repair]. / Affrumað roð: eðliseiginleikar sem styðja vefjaviðgerð.

INTRODUCTION: Acellular fish skin of the Atlantic cod (Gadus morhua) is being used to treat chronic wounds. The prevalence of diabetes and the comorbidity of chronic wounds is increasing globally. The aim of the study was to assess the biocompatibility and biological characteristics of acellular fish skin, important for tissue repair. MATERIALS AND METHODS: The structure of the acellular fish skin was examined with microscopy. Biocompatibility of the graft was conducted by a specialized certified laboratory. Protein extracts from the material were analyzed using gel electrophoresis. Cytokine levels were measured with an enzyme linked immunosorbent assay (ELISA). Angiogenic properties were assessed with a chick chorioallantoic membrane (chick CAM) assay. RESULTS: The structure of acellular fish skin is porous and the material is biocompatible. Electrophoresis revealed proteins around the size 115-130 kDa, indicative of collagens. The material did not have significant effect on IL-10, IL-12p40, IL-6 or TNF-α secretion from monocytes or macrophages. Acellular fish skin has significant effect on angiogenesis in the chick CAM assay. CONCLUSION: The acellular fish skin is not toxic and is not likely to promote inflammatory responses. The graft contains collagen I, promotes angiogenesis and supports cellular ingrowth. Compared to similar products made from mammalian sources, acellular fish skin does not confer a disease risk and contains more bioactive compounds, due to less severe processing.