Description: This technology is a new ex-vivo application for sonothrombolysis (SNT), which combines the use of ultrasound (US) probes and microbubbles timely infused through the arterial port of liver allografts being preserved by a machine perfusion (MP) system. The US probe pulses induces microbubble oscillation and bursting in a process called cavitation. This ex-vivo technology is intended to remove red blood cells (RBCs) plugs and cellular debris from the hepatic arterial peri-biliary plexus (PBP) prior to liver allograft implantation from organs obtained from donors after cardiac death (“DCD”) These patients experience extended periods of hypoperfusion under anoxic conditions prior to organ recovery. The use of DCD livers poses a significant risk for the subsequent development of ischemic cholangiopathy (IC) by the recipient in the post-operative period. IC is an irreversible complication stemming from prolonged ischemia to the PBP leading into recurrent biliary sepsis and subsequent liver allograft failure. This lethal condition requires mandatory retransplantation while yielding prolonged hospital stays and excessive post-operative costs. Previous attempts to prevent IC after DCD liver transplantation using different technologies have failed. IC is caused by progressive clotting of the small blood vessels supplying the PBP, which prevents blood and oxygen from reaching the biliary tree effectively once the liver is transplanted. The ex-vivo SNT technology was designed to remove the clots ex-vivo while enhancing the oxygenation of the bile duct system before the liver is transplanted. It can be used with all current MP systems currently being evaluated for liver preservation.
Title: 3D Bioprinted Human Trachea for Pediatric Patients
Description: The overall goal of this project is the development and preclinical testing of a tissue engineered trachea for use in pediatric patients. The natural growth of pediatric patients requires that an engineered tissue or organ vital to life must “grow” with the patient. The present project will design, develop, and test in preclinical models, a bioengineered trachea consisting of naturally occurring extracellular matrix (ECM), as a scaffold, that is custom manufactured by 3D printing (Feinberg Laboratory, Carnegie Mellon University). The combined expertise of the Badylak Laboratory, which will acquire and prepare the matrix materials, with the Feinberg Laboratory that has expertise in 3D printing, will produce engineered tracheas that will be tested in a rapidly growing porcine model at the McGowan Institute for Regenerative Medicine. The project is milestone driven and consists of two years of development followed by three years of testing.
PI: William Federspiel, William Wagner, Peter Wearden
Title: Ambulatory Assist Lung for Children
Description: Acute and chronic lung diseases remain the most life threatening causes of death and hospitalization in the pediatric population. Cystic fibrosis (CF), pulmonary hypertension and pulmonary fibrosis have been observed to be the most frequent causes of lung failure in pediatric patients. Mechanical ventilation (MV) and extracorporeal membrane oxygenation (ECMO) have been used to bridge sick kids to transplant. These procedures can lead to poor post-transplant outcomes by their very restrictive nature on mobility. This project will develop a compact respiratory assist device for pediatric patients, the Pittsburgh Pediatric Ambulatory Lung (P-PAL) to replace ECMO as a bridge to transplant or recovery in kids with acute and chronic lung failure. The P-PAL is a wearable and fully integrated blood pump and gas exchange module that will be designed for implantation of inflow cannula and outflow cannula/grafts in the right atrium and pulmonary artery, respectively. The P-PAL will be designed for longer-term respiratory support (1-3 months before cartridge change-out) at 70-90% of normal metabolic oxygenation requirements, while pumping blood from 1 to 2.5 Liters/min. The specific aims of project are 1) To modify the design and operational parameters of the P-PAL to meet requirements for blood pumping, gas exchange, priming volume, and form factor, 2) To build P-PAL prototypes along the design development pathway for bench characterization studies of pumping performance, gas exchange, and hemolysis, 3) To improve the hemocompatibility of the P-PAL by exploiting novel polymeric zwitterionic coatings that we have already begun to develop for our adult wearable assist lung, and 4) To perform acute and chronic studies in healthy lambs to demonstrate the in-vivo performance and hemocompatibility of the PAAL device and to study its interaction with the cardiopulmonary system.
Title: Enhanced Neural Prosthetics Using Shared-Mode Control
Description: This project builds on the world’s most advanced program in brain-controlled robotic arms and hands for paralyzed individuals. A group of Pittsburgh scientists and engineers will enhance the performance of neural prosthetics, allowing a paralyzed person to manipulate an object. A prosthetic limb will operate under an individual’s brain control, with a boost from an artificial intelligence component designed to predict what the individual intends to do. This shared-mode control will enable people who have quadriplegia to dexterously handle objects with a robotic arm and hand, and thus increase their independence in daily life.
Title: Endotypes of thrombocytopenia in the critically ill
Description: Thrombocytopenia is extremely frequent in critically ill patients. However, the role of acute platelet responses in critically ill patients is not well studied, and the multifactorial etiology of thrombocytopenia in the ICU makes it difficult to understand, or understand whether or not to treat it. In several situations such as traumatic injury or sepsis, very low platelet counts have been to bleeding, thrombosis and end-organ injury. Platelets have been extensively studied as a key component of hemostasis, but a rapidly emerging concept is that platelets are also key effector cells in systemic inflammatory processes as both instigators of local and systemic inflammatory reactions and also participants in the inflammation that contributes to tissue injury. The link between platelets and inflammation is complex and bidirectional, as inflammatory ligands have been shown to regulate platelet function and activated platelets induce inflammatory responses in other cell types. The overarching theme of this proposal is to study platelet dynamics in critically ill patients, construct clinical endotypes of thrombocytopenia in this population, and to relate these endotypes to underlying mesoscale mechanisms through computational modeling. We will use a large electronic health record-based database and a tri-state trauma database as source data to construct these endotypes. We define endotype as clinical patterns defined along four dimensions: (1) baseline information (demographic, chronic disease burden, severity of illness and admitting diagnosis), (2) features of the platelet count time series (rate of decrease, nadir, etc.), (3) concurrent interventions, and (4) outcome. The computational approach will attempt to root clinical endotypes in mechanistic interpretations (or collections of alternative interpretations), contributing to focus basic science investiagtions, and to close key knowledge gaps preventing the design and use of targeted anti-platelet-inflammatory therapies in the critically ill. Computational models will be developed at different levels of complexity, with a specific attention to tie underlying mechanisms to functional assays routinely performed in thrombocytopenic patients, such as prothrombin time, activated coagulation time, and thromboelastogram.
Description: PUMP is a solution aimed at reducing hospital-acquired pressure ulcers, affecting an estimated 3 million patients annually. The monitoring and alert solutions, using wearable devices and hospital bed sensors, will provide real-time documentation of patient repositioning and a process to improve compliance with these preventative measures.
Title: IPA#14 – Development and Evaluation of Xenografts for Soft Tissue Reconstruction; IPA#15 – Development and/or Evaluation of Synthetic Materials, Synthetic/Biologic Material Composites, surgical hemostats/sealants/adhesives and/or Methods for Improving the Host Tissue Response to Such Materials; IPA#16 – Development and/or Refinement of In Vitro Methods which would Characterize and/or Predict the Host Response to a Test Article; and IPA#17 – Development / Refinement of Preclinical Models and Ex-Vivo Test Methods
Title: Outside-In Regenerative Therapy for Abdominal Aortic Aneurysm
Description: Few diseases represent the optimal potential target for regenerative cellular therapy more than the abdominal aortic aneurysm (AAA). A disease that affects a large number of elderly in the United States with a natural history that results in structural failure of the aortic wall and death, AAA continues to represent a critical need for biologic therapy. Regenerative therapy consisting of the delivery of stem cells to the damaged aorta presents a conceptually strong opportunity for the reconstitution of the aortic mural matrix and therefore aortic strength – any test of such a therapy must be done on an established aneurysm to most accurately represent what occurs in the clinic. In this proposal, we have combined the strengths of two laboratories with complementary scientific capability, and with a common interest in the development of effective biologic therapies for AAA disease. The early product of this collaborative pairing is published “proof of concept” evidence that mesenchymal stem cell (MSC) delivery to the wall of a murine AAA can slow progression. The purpose of this R21 Exploratory/Developmental Research Proposal is to develop a clinically- translatable MSC delivery system that would result in aortic matrix repair and regeneration. Our hypothesis is that local stem cell delivery to a murine AAA via an adventitially-applied hydrogel and magnetic assistance will result in intramural cell engraftment, matrix repair, and mechanical stabilization of the aortic wall. To address our hypothesis, we will execute the following specific aims: Specific Aim 1 is to develop and validate a technique to deliver MSCs into the aortic wall periadventitially using a hydrogel vehicle and magnetic guidance. The technique will be optimized by testing a cadre of iron nanoparticle types, fibrin hydrogel formulations, and stem cell concentrations both in vitro and in vitro. Specific Aim 2 is to demonstrate that local MSC delivery halts and reverses the functional and structural degeneration of an AAA in an established rodent model. MSC hydrogels developed in Specific Aim 1 will be applied to the adventitia of an elastase-induced model AAA after allowing for varying degrees of matrix degeneration. Metrics for success of the various therapies versus cell-free hydrogel controls on aortic tissue will involve: i) functional assessment (including aortic diameter and biomechanical parameters) and ii) detailed microstructural and cellular composition assessment. The expected outcome of this work is the development and proof-of-concept of a new technology for stem cell delivery to AAA.
PI: Michael L. Boninger, MD and Thomas A. Rando, MD
Title: Alliance for Regenerative Rehabilitation Research & Training (AR3T)
Description: The advancement of regenerative medicine principles and technologies holds great potential to drive progress in the prevention and treatment of individuals with a host of pathologies resulting from injury, disease or aging. The long-term goal of regenerative medicine is to promote the repair, replacement, or regeneration of tissues. Likewise, rehabilitation seeks to harness the body’s innate regenerative potential in order to maximize function. Both fields hold great potential to drive progress in the treatment of a host of acute and chronic pathologies. We propose that these two fields are inextricably intertwined; an intersection of disciplines known as Regenerative Rehabilitation. To fully realize the tremendous potential of Regenerative Rehabilitation, we must promote the interaction of basic scientists with rehabilitation specialists. We must also train rehabilitation clinicians who can help oversee the quality, safety, and validity of these innovative Regenerative Rehabilitation technologies. The overarching goal of the Alliance for Regenerative Rehabilitation Research & Training (AR3T) is to establish a national network that will expand scientific knowledge, expertise and methodologies across the domains of regenerative medicine and rehabilitation.
Description: Sepsis, a clinical systemic inflammatory response syndrome occurring in patients following infection or injury, remains the leading cause of death in intensive care units worldwide, including the United States. Emerging evidence indicates that immunometabolism may play an important role in the pathogenesis of sepsis through its ability to regulate the expression and release of cytokines. In particular, we recently provided the first direct evidence that PKM2-mediated aerobic glycolysis promotes the release of HMGB1, a late mediator of lethal systemic inflammation with a wider therapeutic time window for clinical intervention. These exciting findings raise several important questions regarding the previously unknown role of PKM2 in the pathogenesis of sepsis, as well as the novel mechanisms underlying the regulation of PKM2 expression and HMGB1 release. We hypothesize that PKM2-mediated immunometabolism is an emerging hallmark of sepsis that contributes to cytokine (e.g., HMGB1) release and the subsequent systemic inflammatory response. We propose the following specific aims:
Title: Extracellular Matrix as a Therapy for Inflammatory Bowel Disease
Description: Clinical Problem: Inflammatory Bowel Disease (IBD) affects nearly 1.5 million Americans with approximately 70,000 new cases diagnosed each year. There are a number of forms of IBD most notably ulcerative colitis (UC) and Crohn’s disease, but the medical device therapy described in this work could also address proctitis, proctosigmoiditis, and rectal mucositis. UC is the initial research target that may or may not include the other forms of inflammatory disease in the colon. UC significantly increases the risk of developing colorectal cancer and negatively impacts quality of life. The etiology of UC is unknown but altered intestinal barrier function and production of cytotoxic effector molecules within the mucosal lining of the colon are known to play central roles in the development of UC. The proposed work would investigate and evaluate the ability of a hydrogel form of extracellular matrix (ECM) to restore structure and function of the mucosal lining of the colon in a preclinical UC model. These findings would represent an important contribution to required regulatory filings prior to human studies.
PI Stephen Badylak
Title Development of Tissue Engineered Arterial Grafts
Description: The purpose of this study is to evaluate the effectiveness of TEAGs (cell coated) and uncoated (un-TEAGs) as peripheral blood conduits in a sheep animal model in relation to the following.
TEAGs revascularization in vivo
Source: CR Bard
Term 06/15/2015 – 12/31/2016
Title Evaluation of ECM Hydrogel as a Treatment for Stroke Injury
Description: Products composed of mammalian Extracellular Matrix (ECM) have been regulated as a “device” by the FDA, and these materials have been used as a bioscaffold for the repair and reconstruction of soft tissues for the past 15 years. Work in the Badylak laboratory has shown that such matrix materials, when properly prepared, can minimize fibrous tissue deposition and induce a constructive and functional tissue remodeling response. This constructive response is due, at least in part, to bioactive cryptic peptides created during the process of scaffold degradation. Bioactive properties of these oligopeptides include chemoattraction for endogenous stem and progenitor cells, angiogenesis, and modulation of the innate immune response toward a regulatory and constructive “M2”phenotype.
Title Injectable Engineered Tissue for Cancer Reconstruction
Description: Breast reconstruction relieves physical discomfort and psychological distress following mastectomy for over 90,000 women in the United States annually. The limitations of the two main methods, autologous flap procedures and implant procedures, have driven a search for new reconstructive techniques. Autologous tissue operations are highly invasive with a prolonged recovery and risk for major donor site morbidity. Implant reconstruction avoids a donor wound, but is fraught with problems of scar contracture (20%), displacement (5%), rupture (5% in 5 years), and an overall reoperation rate of 50%. Additionally, both these therapies are poorly suited for the significant number of women with deformities after lumpectomy.
Title NSF Engineering Research Center for Revolutionizing Metallic Biomaterials
Description: The Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB) will pursue revolutionary advances in metallic biomaterials and the underlying sciences and technologies, leading to engineered systems that will interface with the human body to prolong and improve quality of life. This research effort is coupled with the development of a vibrant, diverse workforce well-prepared for the global challenges and opportunities of the 21st century. The ERC proposes to develop the fundamental knowledge and technology needed to advance biocompatible and biodegradable metal-based, implantable systems with feedback control for reconstruction and regeneration. The research and technology development will be aided by industrial input and clinical assessments. The ERC’s education program is designed to develop innovative and adaptive engineers. Seamlessly integrated undergraduate and graduate bioengi- neering programs will be established at North Carolina A&T State University (NCAT) to support this goal.
Title Mechanisms of Polyploidy and Aneuploidy in the Liver
Description: Nearly 25 million Americans are affected by liver dysfunction, and liver diseases are the 10th leading cause of death in the US. There is a clear and urgent need for developing new alternatives to whole organ replacement. A better understanding of liver biology is required to improve existing approaches and to innovate therapies for the treatment of liver diseases, including viral hepatitis and steatohepatitis. Hepatocytes, the primary functional cell type in the liver, display a range of chromosomal diversity resulting from prevalent physiological polyploidy (>90% in mice and 50% in humans) and aneuploidy (60% in mice and 30-90% in humans). In eukaryotic organisms, cells usually contain a diploid genome comprised of pairs of homologous chromosomes. Polyploidy refers to gains in entire sets of chromosomes, and aneuploidy refers to gains and losses of individual chromosomes. The roles of hepatic polyploidy and aneuploidy represent a major gap in our current understanding of liver biology. We recently found that aneuploidy enhances the regenerative capacity of the mouse liver. In response to Tyrosinemia-induced injury, that is normally toxic to the liver, we identified a subset of aneuploid hepatocytes that was resistant to the disease. The data suggest that aneuploid hepatocytes are endowed with enhanced capacity for adaptation and regeneration. Our central hypothesis is that aneuploidy functions as an adaptive mechanism in response to hepatic injury. The goals of this application are to identify mechanisms regulating hepatic aneuploidy/polyploidy and to unravel how aneuploidy affects liver function. To investigate these questions, we propose in Specific Aim 1 to determine whether polyploid hepatocytes are necessary for development of aneuploid livers. Experiments will characterize hepatic cell divisions, karyotypes and stress response in E2f7/E2f8 knockout mice, which have normal liver function but are depleted of polyploid hepatocytes. In Specific Aim 2, we will dissect the role of a novel regulator of hepatic polyploidy, recently identified in our laboratory, microRNA-122 (miR-122). Experiments will determine how miR-122 alters ploidy and aneuploidy throughout life. We will also identify cellular and molecular mechanisms by which miR-122 regulates hepatic ploidy. Finally, in Specific Aim 3, we will determine how random karyotypes (in aneuploid hepatocytes) affect function in the liver. We will utilize a novel xenotransplantation model to examine clonal nodules of regenerating human hepatocytes. Experiments will measure aneuploidy and determine gene expression profiles in these nodules. Together, these studies will define the extent to which aneuploidy affects liver repair/regeneration as well as the molecular mechanisms that control this process. Understanding how aneuploid hepatocytes arise and function will provide new and crucial insights into liver homeostasis, diseases and treatments.
Title Mini-Livers Derived from Human IPS Cells for Modeling Steatosis and Therapy
Description: Our long-term goal is to develop a natural hepatic scaffold with multi-cellular cues for complete and stable maturation of stem-derived liver cells to engineer functional livers in vitro and use them for modeling liver steatosis and therapeutics. The objectives of the proposed study are to develop an organ culture system for liver engineering with induced pluripotent stem (iPS) cell-derived liver cells, and investigate its employment to understand pathogenesis, natural history and development of early detection tools and treatments for fatty liver diseases. The central hypothesis to be tested here is that the decellularized natural liver scaffold can be extensively repopulated, will provide a stable organ-like environment for the metabolic maturation of iPS derived liver cells, and may be used as an approach to induce formation of functional mini-livers using human wild type iPS cells or iPS cells after genetic engineer for fatty liver disease by knockdown of SIRT1 and/or (key gene implicated with liver steatosis formation). The rationale for the proposed research is that, once human liver tissue with multi-cellular cues can be reproducibly manufactured in vitro with normal and disease phenotypes, development of liver steatosis can be manipulated pharmacologically, resulting in new and innovative approaches to the prevention and treatment of a variety of liver diseases. The work described here is expected to i) generate a metabolic maturation system for human iPS cell-derived liver cells to form tissue, ii) establish human iPS cells carrying shRNA mediated conditional knockdown of SIRT1 and iii) develop a novel approach for modeling an organ-like environment to determine the role of SIRT1 in human liver steatosis or fatty liver disease. The results of this work will also have a positive impact by establishing the basis and platform for future sophisticated organ engineering techniques that incorporates several different cell types and may lead to development of entire organs in vitro, these techniques could be applied to study other liver diseases (e.g. metabolic diseases) and is expected to be a major contribution to the fields of stem cells engineering and liver steatosis.
Title Applying extracellular matrix technology to neuroprotect and to repair injured retina and optic nerve
Description: ECM technology as an early preventative for reducing secondary ocular trauma. After ocular trauma, secondary injury due to inflammation and a default healing response that forms scar tissue, in injured central nervous system (CNS) tissues, are major factors contributing to permanent vision loss. To address this problem, we are developing an injectable, ECM hydrogel and an ECM biohybrid wrap. Both platforms are designed to stabilize trauma to the retina or to the optic nerve and limit inflammation, edema, and scarring. ECM technology uses natural ECM bioscaffolds, derived by decellularizing specific tissues or organs, to promote a positive healing response in tissues the body is unable to repair functionally by default. In both preclinical and clinical models, ECM bioscaffolds can facilitate site-specific, functional repair in various peripheral tissues, including heart, lung, esophagus, muscle, tendon, skin, and peripheral nerves among others. Though the exact mechanisms are unknown, ECM bioscaffolds act, in part, by attracting endogenous stem cells and promoting site-appropriate differentiation, vascularization, neurogenesis, and a pro-repair M2 phenotype in macrophage and microglia. We hypothesize ECM technology will preserve or restore visual function by altering the default healing response to retinal or optic nerve injury in four key areas: 1) Increase RGC survival and axon regeneration. 2) Increase endogenous stem cell recruitment to the wound. 3) Increase M2 polarization in macrophages and microglia at the wound site. 4) Decrease glial scarring.
Title Non-invasive imaging of the in situ restoration of brain tissue
Description: Regenerative medicine is increasingly finding translations from the bench to the bedside. As stem cells are integrated with biomaterials for in situ tissue engineering, the complexity of the procedure is increasing and it is becoming important to monitor how these processes interact over time in vivo. Translation of this non-invasive monitoring into patients requires the development and implementation of appropriate approaches. Our proposal here aims to develop chemical exchange saturation transfer (CEST), a non-invasive MRI technique, as a core platform to visualize multiple cell types, as well as biomaterials, while maintaining our ability to characterize newly forming tissue with other MRI techniques, such as MRS, as well as diffusion and perfusion MRI. Very significant technological, as well as neurobiological challenges, however, need to be addressed before we can integrate this multi-parametric MRI into an efficient non-invasive assessment of in situ tissue engineering. The proposed studies aim to address these challenges and provide a framework within which we can eventually explore the therapeutic potential of this approach. If a newly functional tissue can be generated to replace that which is lost due to the stroke, this approach could indeed dramatically change the long-term outcome after stroke.
Title 3D Video Augmented High-Resolution Ultrasound Imaging for Monitoring Nerve Regeneration and Chronic Rejection after Composite Tissue Allotransplantation
Description: This technology has direct relevance to the FY13 PRMRP topic area of Composite Tissue Transplantation. During the past decade, more than 100 hand and facial transplants have been performed around the world, including over 90 with encouraging outcomes. The University of Pittsburgh is one of the key centers for these exciting new surgical procedures. Key to their success is the timely regrowth of nerves into the new transplanted tissue before muscle has time to degenerate, and the survival of vital arteries that tend to thicken with chronic rejection of the transplant, putting transplanted tissue at risk. Monitoring nerves and arteries is thus essential for appropriate measures to be taken in time and, in the research setting, it is required so that new therapies can be developed. To be safe, monitoring of nerves and arteries in these patients must not involve taking biopsies. Imaging techniques using ultrasound are promising because of their safety and low cost, and recent advances in ultrasound resolution have made subtle changes in nerves and arteries more easily visualized. However, ultrasound still suffers from an inability to accurately record where in a patient a given ultrasound scan has been acquired. The knowledge of scan location is particularly important for comparing ultrasound scans from one month to the next, and from one patient to another.