Evaluation of 3D PLLA scaffolds coated with nano-thick collagen as carrier for hepatocytes.

Orthotopic liver transplantation is presently the most effectual method for the treatment of end-stage liver diseases. Though, one major issue is the restricted number of donor organs that are accessible. Hence, liver tissue engineering is under investigation with the goal of restoring liver functions. In this study, we investigated 3D porous scaffolds made of PLLA coated with a nano thick collagen layer (matrices). Primary rat dermal fibroblasts were used in a first study phase to check matrices' cytocompatibility. More than 70% of seeded cells could adhere and remain viable 24 and 48 hours after the seeding. To test the suitability of the matrices for human primary hepatocytes, HepaRG cells were seeded and analyzed for viability, adhesion rate, and functionality such as albumin secretion. About 80% of seeded HepaRG adhered to the scaffolds remaining viable up to 72 hours. Cells were homogeneously distributed in the entire scaffold with albumin secretion increasing with time. Our results indicate that PLLA collagen-coated matrices allow hepatocytes attachment and distribution throughout the 3D structure, as well as support cell functionality. Such matrices have been applied in our clinical phase II trial. Functional hepatocytes were successfully implanted in patients suffering from liver-cirrhosis with higher cell numbers and adhesions rate compared to our previous trial with the first matrix type and a general improvement in clinical condition.

Allogeneic islet cells implant on poly-l-lactide matrix to reduce hyperglycaemia in streptozotocin-induced diabetic rat.

OBJECTIVE: To demonstrate the effects of allogeneic islet cell matrix implants for glycaemic control in rats with induced diabetes. METHOD: Sprague-Dawley rats were used as allogeneic donors of islet cells. Cells were seeded on three-dimensional proprietary poly-(l-lactide) matrices. Animals were rendered diabetic and a week later a matrix seeded with islet cells (IMI group) or a control matrix (placebo group) was implanted in the small bowel mesentery. Blood glucose levels were measured weekly for 12 weeks. After sacrifice, implant sections were Gomori stained for beta-cells and immuno-stained for insulin 3, 4, 5, and 6 months post implantation. RESULTS: 82% of seeded islet cells attached to the matrices. In the IMI group blood glucose levels were significantly reduced after implantation compared with before implantation across several time points. In the IMI group beta-cells and insulin-positive cells were identified at the implant site. CONCLUSION: The islet cell matrix implant reduced the blood glucose levels although complete normo-glycaemia was not established. The islet cell matrix implant may serve as an additional option for islet cell transplantation using 3D scaffold platforms for better survival and function of the islet cells.

Humiliation: the lasting effect of torture.

Although the physical effects of torture in surviving persons are well known, psychological wounds are lesser known and investigated. A new aspect of considerable impact is the notion of shame, self-humiliation, and the ensuing problems of degradation. Further research on the evolving concept of post-torture illness should be performed.

The changing face of the Course.

The commander of the International Course on Law of Armed Conflict, which is under the auspices of the International Committee of Military Medicine, summarizes his experiences and the changing subjects of interests during the course in Switzerland.

Extended preservation of rat liver graft by induction of heme oxygenase-1.

Livers can be preserved only for a short period without jeopardizing the transplantation outcome. Heat shock proteins (HSPs) protect against ischemia and reperfusion injury. We studied whether their induction and, in particular, the induction of heme oxygenase 1 (HO-1), improves transplantation survival after an extended time of cold storage. Rats were subjected to heat preconditioning (42 degrees C for 20 minutes). Livers were harvested 24 hours later, preserved in cold University of Wisconsin solution for 44 hours, and transplanted in isogeneic rats (arterialized transplantation). HO-1 was specifically induced and inhibited by cobalt protoporphyrin and tin protoporphyrin, respectively. All animals receiving a graft without preconditioning and subjected to 44 hours of cold preservation died within 3 days, whereas 89% of rats who received a graft exposed to heat survived for 3 weeks (P =.0004). Preconditioning reduced serum aspartate transaminase (AST) and lactate dehydrogenase activities after reperfusion, improved bile flow, and decreased the histologic lesions of reperfusion injury. These significant effects of heat preconditioning were prevented by administration of tin protoporphyrin and could be reproduced by administration of cobalt protoporphyrin. In grafts without preconditioning, only a small fraction (<5%) of hepatocytes were positive with the terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) assay, and even less expressed activated caspase 3. Preconditioning tended to reduce the number of positive cells and to stimulate the expression of antiapoptotic Bcl-X(L). In conclusion, heat preconditioning and, specifically, overexpression of HO-1 improve posttransplantation survival and graft function after prolonged cold ischemia preservation. The mechanism underlying these beneficial effects does not appear to be prevention of apoptosis.