Chiara Attanasio

Functional and morphological comparison of three primary liver cell types cultured in the AMC bioartificial liver

The selection of a cell type for bioartificial liver (BAL) systems for the treatment of patients with acute liver failure is in part determined by issues concerning patient safety and cell availability. Consequently, mature porcine hepatocytes (MPHs) have been widely applied in BAL systems. The success of clinical BAL application systems is, however, largely dependent on the functionality and stability of hepatocytes. Therefore, we compared herein the general metabolic and functional activities of MPHs with mature human hepatocytes (MHHs) in the Academic Medical Center (AMC)‐BAL during a 7‐day culture period. We also tested fetal human hepatocytes (FHHs), since their proliferation capacity is higher than MHHs and their function is increased compared to human liver cell lines. The results showed large differences between the 3 cell types. MHHs eliminated 2‐fold more ammonia and produced 3‐fold more urea than MPHs, whereas FHHs produced ammonia. Lidocaine elimination of FHHs was 3.5‐fold higher than MPHs and 6.6‐fold higher than of MHHs. Albumin production was not different between the 3 cell types. MPHs and FHHs became increasingly glycolytic, whereas MHHs remained metabolically stable during the whole culture period. MHHs and MPHs formed tissue‐like structures inside the AMC‐BAL. In conclusion, we propose that FHHs can be considered as a suitable cell type for pharmacological studies inside a bioreactor. However, we conclude that MHHs are the preferred cell source for loading a BAL device for clinical use, because of their high ammonia eliminating capacity and metabolic stability. MPHs should be considered as the best alternative cell source for BAL application, although their phenotypic instability urges application within 1 or 2 days after loading. Liver Transpl 13:589–598, 2007.

Intraoperative administration of inhaled carbon monoxide reduces delayed graft function in kidney allografts in Swine.

Ischemia/reperfusion injury and delayed graft function (DGF) following organ transplantation adversely affect graft function and survival. A large animal model has not been characterized. We developed a pig kidney allograft model of DGF and evaluated the cytoprotective effects of inhaled carbon monoxide (CO). We demonstrate that donor warm ischemia time is a critical determinant of DGF as evidenced by a transient (4–6 days) increase in serum creatinine and blood urea nitrogen following transplantation before returning to baseline. CO administered to recipients intraoperatively for 1 h restored kidney function more rapidly versus air‐treated controls. CO reduced acute tubular necrosis, apoptosis, tissue factor expression and P‐selectin expression and enhanced proliferative repair as measured by phosphorylation of retinol binding protein and histone H3. Gene microarray analyses with confirmatory PCR of biopsy specimens showed that CO blocked proinflammatory gene expression of MCP‐1 and heat shock proteins. In vitro in pig renal epithelial cells, CO blocks anoxia‐reoxygenation‐induced cell death while promoting proliferation. This large animal model of DGF can be utilized for testing therapeutic strategies to reduce or prevent DGF in humans. The efficacy of CO on improving graft function posttransplant validates the model and offers a potentially important therapeutic strategy to improve transplant outcomes.

Induction of protective genes leads to islet survival and function.

Islet transplantation is the most valid approach to the treatment of type 1 diabetes. However, the function of transplanted islets is often compromised since a large number of β cells undergo apoptosis induced by stress and the immune rejection response elicited by the recipient after transplantation. Conventional treatment for islet transplantation is to administer immunosuppressive drugs to the recipient to suppress the immune rejection response mounted against transplanted islets. Induction of protective genes in the recipient (e.g., heme oxygenase-1 (HO-1), A20/tumor necrosis factor alpha inducible protein3 (tnfaip3), biliverdin reductase (BVR), Bcl2, and others) or administration of one or more of the products of HO-1 to the donor, the islets themselves, and/or the recipient offers an alternative or synergistic approach to improve islet graft survival and function. In this perspective, we summarize studies describing the protective effects of these genes on islet survival and function in rodent allogeneic and xenogeneic transplantation models and the prevention of onset of diabetes, with emphasis on HO-1, A20, and BVR. Such approaches are also appealing to islet autotransplantation in patients with chronic pancreatitis after total pancreatectomy, a procedure that currently only leads to 1/3 of transplanted patients being diabetes-free.

A method to tune the shape of protein-encapsulated polymeric microspheres.

Protein encapsulation technologies of polymeric microspheres currently in use have been optimized to effectively protect their “protein cargo” from inactivation occurring in biological environments, preserving its bioactivity during release up to several weeks. The scenario of protein delivery would greatly benefit by strategies enabling the production of non-spherical particles. Herein we report an easy and effective stamp-based method to produce poly-lactic-glycolic-acid (PLGA) microparticles encapsulating Vascular Endothelial Growth Factor (VEGF) of different shapes. We demonstrate that PLGA microspheres can be deformed at room temperature exploiting solvent/non-solvent plasticization in order to preserve the properties of the starting microspheres. This gentle method allows the production of shaped particles that provide a prolonged release of VEGF in active form, as verified by an angiogenic assay. The retention of the biological activity of an extremely labile molecule, i.e. VEGF, lets us hypothesize that a wide variety of drug and protein encapsulated polymeric microspheres can be processed using this method.

Biliverdin Protects against Liver Ischemia Reperfusion Injury in Swine

Ischemia reperfusion injury (IRI) in organ transplantation remains a serious and unsolved problem. Organs that undergo significant damage during IRI, function less well immediately after reperfusion and tend to have more problems at later times when rejection can occur. Biliverdin has emerged as an agent that potently suppress IRI in rodent models. Since the use of biliverdin is being developed as a potential therapeutic modality for humans, we tested the efficacy for its effects on IRI of the liver in swine, an accepted and relevant pre-clinical animal model. Administration of biliverdin resulted in rapid appearance of bilirubin in the serum and significantly suppressed IRI-induced liver dysfunction as measured by multiple parameters including urea and ammonia clearance, neutrophil infiltration and tissue histopathology including hepatocyte cell death. Taken together, our findings, in a large animal model, provide strong support for the continued evaluation of biliverdin as a potential therapeutic in the clinical setting of transplantation of the liver and perhaps other organs.

Update on Renal Replacement Therapy: Implantable Artificial Devices and Bioengineered Organs.

Recent advances in the fields of artificial organs and regenerative medicine are now joining forces in the areas of organ transplantation and bioengineering to solve continued challenges for patients with end-stage renal disease. The waiting lists for those needing a transplant continue to exceed demand. Dialysis, while effective, brings different challenges, including quality of life and susceptibility to infection. Unfortunately, the majority of research outputs are far from delivering satisfactory solutions. Current efforts are focused on providing a self-standing device able to recapitulate kidney function. In this review, we focus on two remarkable innovations that may offer significant clinical impact in the field of renal replacement therapy: the implantable artificial renal assist device (RAD) and the transplantable bioengineered kidney. The artificial RAD strategy utilizes micromachining techniques to fabricate a biohybrid system able to mimic renal morphology and function. The current trend in kidney bioengineering exploits the structure of the native organ to produce a kidney that is ready to be transplanted. Although these two systems stem from different technological approaches, they are both designed to be implantable, long lasting, and free standing to allow patients with kidney failure to be autonomous. However, for both of them, there are relevant issues that must be addressed before translation into clinical use and these are discussed in this review.

Enhanced Drug Delivery into Cell Cytosol via Glycoprotein H-Derived Peptide Conjugated Nanoemulsions

The key role of nanocarriers in improving the pharmacological properties of commonly used drugs is recognized worldwide. It is also known that in the development of new effective nanocarriers the use of targeting moieties integrated on their surface is essential. Herein, we propose a nanocarrier based on an oil in water nanoemulsion coated with a membranotropic peptide derived from the glycoprotein H of Herpes simplex virus 1, known as gH625, in order to reduce endolysosomal accumulation and to enhance cytosolic localization. In addition, we show an enhanced anti-inflammatory activity of curcumin, a bioactive compound isolated from the Curcuma longa plant, when loaded into our engineered nanocarriers. This effect is a consequence of a higher uptake combined with a high curcumin preservation exerted by the active nanocapsules compared to control ones. When loaded into our nanocapsules, indeed, curcumin molecules are directly internalized into the cytosol rather than into lysosomes. Further, in order to extend the in vitro experimental setting with a more complex model and to explore the possibility to use our nanocarriers for further biological applications, we tested their performance in a 3D sprouting angiogenesis model. Finally, we show promising preliminary in vivo results by assessing the anti-inflammatory properties of the proposed nanocarrier.

The impact of innovation for biotech drugs: an Italian analysis of products licensed in Europe between 2004 and 2011

Objective Biotechnology has promoted the discovery and development of new types of therapeutical agents for use in humans: biotech drugs offer innovative, targeted therapies with enormous potential to address unmet medical needs of patients with cancer, AIDS and other serious diseases. However, the therapeutic application of these novel therapies poses serious problems concerning the connection between cost sustainability and innovative value. The aims of the present study are to assess the level of therapeutic innovation of biotech drugs approved by the European Medicines Agency between 2004 and 2011, to make a comparison with the trend of biotech drugs approved between 1995–2003, as previously reported, and to evaluate their economic impact on the Italian healthcare system. Methods The data source used was the European Public Assessment Report (EPAR) of human medicines available on European Medicines Agency (EMA) website. The scores for therapeutic innovation were assigned according to the algorithm created by Motola et al. Drug expenditure data was obtained from Information Management System–Health Italy database. The list of drugs under analysis was downloaded from European Medicines Agency website and information on approved drugs were retrieved from the European Public Assessment Reports as well as from PubMed databank. Results From 2004 to 2011, the European Medicines Agency approved 47 biotech drugs: 43 biopharmaceutical innovators and 4 vaccines. Our analysis involved 33 of the 47 biotech drugs approved: 18 products resulted in important therapeutic innovations, 6 in moderate and 5 in modest therapeutic innovations, 2 in pharmacological innovations and finally, 2 involved only technological innovations. We also evaluated the influence of biotech drugs and their different scores for innovation with regard to expenditure as well as consumption. In 2010 and in 2011, the major part of expenditure and consumption concerned biotech drugs classified as important therapeutic innovations, while moderate, modest, pharmacological and technological innovators revealed very reduced contributions in this regard. Conclusions Our study revealed that 50% of biotech drugs approved between 2004–2011 represented an important or moderate therapeutic innovation. The remaining biotech drugs did not add any extra value in the decision-making process concerning the application of economic strategies in the healthcare field. These considerations suggest decision-makers should optimise application of health technology assessment strategies aimed at evaluating new technologies and sustainable costs in clinical practice.

Bioreactors for Cell Culture Systems and Organ Bioengineering

Abstract Significant advances in the field of bioartificial devices have occurred over the last two decades that have contributed greatly to the field of organ replacement therapeutics. Some of these advances have already entered the clinic while others continue to be developed and perhaps will be suitable to be translated into clinical use soon. The biomimetic, tightly controlled microenvironment provided by bioreactor systems plays a key role in the creation of bioengineered grafts with optimal morphology and function. Additionally the use of bioscaffolds generated through novel perfusion decellularization techniques is a powerful approach towards bioengineering of total parenchymal organs inclusive of highly organized vascular networks. Amidst these exciting advances, challenges remain; including large-scale production, and widespread issues related to the selection of appropriate cell lines for clinical use and protocol standardization that will meet the requirements set forth by regulatory authorities.