A new biodegradable elastin-fibrin material; its use in urological, digestive and cardiovascular surgery

Elastin peptides prepared from piscine and mammalian elastic tissues inhibit collagen-induced platelet aggregation and stimulate migration and proliferation of human skin fibroblasts

We obtained pure elastin peptides from bovine ligamentum nuchae, porcine aorta, and bonito bulbus arteriosus. The inhibitory activity of these elastin peptides on platelet aggregation induced by collagen and the migratory and proliferative responsivenesses of human skin fibroblasts to these elastin peptides were examined. All of bonito, bovine, and porcine elastin peptides found to inhibit platelet aggregation, but bonito elastin peptides showed a higher inhibitory activity than bovine and porcine elastin peptides did. All elastin peptides enhanced the proliferation of fibroblasts 3.5- to 4.5-fold at a concentration of 10 µg/ml. Bovine and porcine elastin peptides stimulated the migration of fibroblasts, with the optimal response occurring at 10(-1) µg/ml, while maximal response was at 10(2) µg/ml for bonito elastin peptides. Furthermore, pretreatment of fibroblasts by lactose depressed their ability to migrate in response to all elastin peptides, suggesting the involvement of elastin receptor in cell response. These results suggest that both mammalian and piscine elastin peptides can be applied as useful biomaterials in which elasticity, antithrombotic property, and the enhancement of cell migration and proliferation are required.

Tissue response of defined collagen–elastin scaffolds in young and adult rats with special attention to calcification

Collagen-elastin scaffolds may be valuable biomaterials for tissue engineering because they combine tensile strength with elasticity. In this study, the tissue response to and the calcification of these scaffolds were evaluated. In particular, the hypothesis was tested that calcification, a common phenomenon in biomaterials, may be due to microfibrils within the elastic fibre, and that these microfibrils might generate a tissue response. Four scaffolds were subcutaneously implanted, viz. collagen, collagen + pure elastin, collagen+microfibril-containing, and collagen + pulverised elastic ligament (the source for elastin). Explants were evaluated at day 3, 7 and 21. In young Sprague Dawley rats, collagen + ligament calcified substantially, whereas collagen + elastin (with and without microfibrils) calcified less, and collagen did not. Calcification started at elastic fibres. In both Sprague Dawley and Wistar adult rats, however, none of the scaffolds calcified. Mononuclear cell infiltration was prominent in young and adult Sprague Dawley rats. In adult Wistar rats, this infiltration was associated with the presence of microfibrils. Degradation of scaffolds and new matrix formation were related with cellular influx and degree of vascularisation. In conclusion, absence of microfibrils from the elastic fibre does not prevent calcification in young Sprague Dawley rats, but does reduce the tissue response in adult Wistar rats. Cellular response and calcification differs with age and strain and therefore the choice of animal model is of key importance in biomaterial evaluation.

Elastin-derived protein coating onto poly(ethylene terephthalate). Technical, microstructural and biological studies

Recently, it has been shown in our laboratory that certain proteins solubilized from elastin (ESP) formed a tight association with certain polymers such as elastin or polyethylene glycol terephthalate (PET) ... . The present paper deals with the description of the optimal chemical conditions of this unexpected association, its microstructure and its biological properties. A microstructural study of the composite ESP-PET material was performed using scanning and transmission electron microscopy. The thickness of the yield composite was evaluated (0.4-2 microm) but its imperviousness was unsatisfactory using ESP alone. So, we tentatively coated PET with the elastin-ESP complex. The microscopic views confirmed that the polymer was better filled by the organic matrix, the thickness of the layer being markedly improved (3 microm). Simultaneously, we attempted to verify whether the yielded composite retains the biological properties previously demonstrated with the 'Biopatches' and probably due to ESP. Thus, the culture of endothelial cells on an ESP-coating (with elastin or not) showed that a 100 microg/cm2 ESP concentration was able to promote endothelial cell growth in perfect conditions, maintaining their phenotypic character. While several physico-chemical determinations are in progress in our laboratory to identify and characterize the protein involved, a prototype of small-calibre vascular prosthesis was elaborated with elastin-ESP-PET composite and will be placed in a dog at the abdominal femoral junction to evaluate the in vivo performance of such an attractive material in artery restoration.

Use of a new elastin patch and glue for repair of a major duodenal injury

Major duodenal injury with significant tissue loss causes high morbidity and mortality. Our new elastin based heterograft combined with small intestinal submucosa (SIS) and biodegradable glue could be used for repair of such defects. Twenty-four domestic pigs were anesthetized and underwent celiotomy. A 2 cm circular defect was created at the second portion of the duodenum with scissors, excising one-half of its circumference. Our elastin patch, combined with SIS, was applied to cover the defect using biodegradable cyanoacrylate glue and a few sutures. It was then covered with omentum. Animals were followed by weight gain, endoscopic evaluation, and upper GI barium studies. After 2-5 months, animals were sacrificed to obtain specimens. One failed in 3 days due to a technical problem, and one failed in 20 days due to an abdominal abscess. The other 22 animals (22/24, 91.7%) did well, gaining weight. Early endoscopic studies (5-14 d) showed an intact patch. Upper GI studies showed varying degrees of stenosis at the repair site at 3-4 months. Sacrifice after 2-5 months showed complete healing of the defect and a dissolved patch. Our new elastin patch material provides a reliable barrier for repair of duodenal injury, and the biodegradable glue provides quick and easy watertight tissue fusion for our patch.

Evaluation of bioabsorbable elastin-fibrin matrix as a barrier in surgical periodontal treatment

The purpose of this investigation was to test clinically the efficiency of a recently described bioabsorbable matrix as a guided tissue regeneration membrane. This matrix was prepared from an original reaction between elastin and fibrin monomers and is now extensively used in several domains of surgery. The study group was composed of 26 patients, with a total of 35 lesions (22 intrabony defects, 8 Class II furcations and 5 Class III furcations) presenting moderate to advanced adult periodontitis. After initial therapy, measurements were made with a calibrated periodontal probe. Probing depth (PD) and gingival margin location (GM) measurements were taken twice: immediately before surgery and after 6 months before re-entry. Clinical attachment level (CAL), vertical osseous level (VOL) and alveolar crest location (AC) measurements were taken during surgery and after 6 months with re-entry procedures for all the patients. Color change of the gingival margin was only observed in 4 defects and device exposure occurred in the proportion of 2 out of the 35 defects. No foreign body reaction was observed in any case. At the intrabony defects mean PD reduction was 5 mm (P < 0.001), and mean gain of CAL was 4 mm (P < 0.001). Mean VOL was 4.3 mm (P < 0.001), mean gingival recession was 0.9 mm (P < 0.05) and mean AC was 0.2 mm (NS). At the Class II furcation defects the mean PD reduction was 4.5 mm (P < 0.001), mean gain CAL vertical was 3.2 mm and CAL horizontal was 4.5 mm (P < 0.001). Gingival recession averaged 1 mm (NS). A complete closure was observed in 2 out of the 8 defects. At the Class III furcation defects the mean PD reduction was 3.6 mm (P < 0.05) and mean CAL-V gain was 1.5 mm (P < 0.02). However the 5 sites showed no horizontal attachment gain and none were unchanged. A very low gingival recession, gingival reaction, crestal bone loss, and device exposure occurred during this study. This preliminary study suggests that the use of a biosynthetic barrier may have beneficial effects in the treatment of intrabony defects and Class II furcation defects. Randomized controlled trials are necessary to evaluate the efficacy and safety of this bioabsorbable membrane in periodontal therapy.

Use of a biodegradable elastin-fibrin material, Neuroplast, as a dural substitute

Since the new Neuroplast biomaterial is now commonly used in several domains of restorative and curative surgery, its preliminary evaluation as a dura mater substitute in the rabbit was performed and is described herein. Whereas the importance of prosthesis thickness was implicated and solved (0.2 rather than 1.0 mm), both macroscopic examination and histological studies revealed for the neotissue an effective patency, a good continuity and especially no or almost no adherence at all. As Neuroplast is now available for use everywhere in humans, this material is being developed in several fields of neurosurgery.

New artificial connective matrix made of fibrin monomers, elastin peptides and type I + III collagens: structural study, biocompatibility and use as tympanic membranes in rabbit

Experiments leading to the conception and development of a new artificial connective matrix based on collagen-elastin-fibrin associations are presented. Preliminary evaluation of this biomaterial as an artificial tympanic membrane is described. Morphological evaluation was performed by histopathological and scanning electron microscopic studies. Biocompatibility was documented by subcutaneous implantation and experimental grafting in rabbits was performed with histopathological studies of the tympanic grafted membranes. The positive results obtained in this experimental study enable future studies in humans to be prepared.