PI William Federspiel, PhD, William R. Wagner, PhD , Christian A. Bermudez, MD, James Antaki, PhD
Co-PI Greg Burgreen, PhD
Title Paracorporeal Ambulatory Assist Lung (PAAL)
Summary: Acute and chronic diseases of the lung remain major healthcare problems. Each year nearly 350,000 Americans die of some form of lung disease. Mechanical ventilation provides short-term support for these patients, but longer term support can lead to barotrauma, volutrauma, and other iatrogenic injuries, further exacerbating the respiratory insufficiency. Extracorporeal membrane oxygenation (ECMO) can provide longer term respiratory support but is complex and significantly limits a patient’s mobility. This project will develop a compact respiratory assist device, the Paracorporeal Ambulatory Assist Lung (PAAL), to replace ECMO as a bridge to transplant or recovery in patients with acute and chronic lung failure. The PAAL is a fully integrated blood pump and gas exchange module and is designed for peripheral cannulation (e.g. jugular to femoral) or central cannulation (e.g. right atrium to pulmonary artery and worn on a holster or vest. The PAAL will be designed for longer-term respiratory support (1-3 months before change-out) at 70-100% of normal metabolic requirements, while pumping blood from 2 to 3.5 Liters/min. The specific aims of project are 1) To optimize the design and operational parameters of the PAAL to meet requirements for blood pumping, gas exchange, priming volume, and form factor; 2) To build PAAL prototypes along the design development pathway for bench characterization studies; 3) To improve hemocompatibility of the PAAL by exploring novel molecular Zwitterionic coatings; and 4) To perform acute and chronic animal studies in healthy sheep to demonstrate the in-vivo performance and hemocompatibility of the PAAL device and its interaction with the cardiopulmonary system.
Title Blood Filtration System for the Treatment of Severe Malaria Patients
Description The overall goal of the proposed project is to develop a novel blood filtration system, mPharesis™, for the treatment of severe malaria patients. The World Health Organization estimates that each year approximately 300 million malaria episodes occur globally resulting in nearly one million deaths, 85% of which are children. The majority of deaths are caused by severe malaria. Severe malaria is a leading cause of pediatric morbidity, hospitalization, and mortality in Sub-Saharan Africa. It is responsible for more than 200,000 cases of fetal loss and more than 10,000 maternal deaths annually. Severe malaria also occurs in 5% of the nearly 30,000 imported malaria cases by travelers from endemic areas. Even when managed aggressively with intravenous antimalarial drugs (artesunate or quinine) mortality rates range between 10%-22%, and as high as 40% for the most complicated cases. Blood exchange transfusion (ET) and erythropheresis (EP) have been effectively used to significantly accelerate the clearance of malaria infected red blood cells from circulation. A large body of medical studies has shown that these treatments if available are beneficial. However, the current systems used to perform these therapies are not engineered to selectively separate the infected cells from the non infected. Thus, to remove these toxic infected cells the entire patient’s blood is disposed – wasting in most cases between to 70%-95% of the healthy blood. This inefficacy results in larger than needed consumption of donor blood. Consequently, ET and EP therapies remain a prerogative of industrialized nations. This is precisely the motivation for developing the proposed mPharesis™ system – a system that will allow the removal of toxic infected red blood cells from the patient’s blood circulation with minimal or no use of donor blood. The mPharesis™ filter operates by targeting these cells’ unique (and well-known) magnetic properties. This system represents the first medical device of its kind to employ magnetic separation technology to clear these toxic cells from circulation. In this SBIR Phase 1 effort, we will complete the design verification of a first-generation mPharesis™. This objective will be accomplished by entailing experimentation and numerical simulation, to achieve a prototype optimized for high-throughput, high separation efficiency, and low residual parasitic load. In specific, the successful completion of this Phase 1, will yield a working prototype, suitable for animal testing (in Phase 2), capable of reducing the parasitic load (40%) to less than 1.0% within a time period of 3-4 hours, and demonstrating satisfactory hemocompatibility. mPharesis™ is intended for those millions of children and adults who have already reached the severe malaria stage, and will provide a life-saving measure for cases that do not respond well to conventional treatments — as too often occurs in the advanced severe stages of this deadly disease.
Title Experiential Learning for Veterans in Assistive Technology and Engineering
Description This engineering education research project will investigate the effectiveness of several different interventions designed to retain disabled veterans in engineering degree programs. A comparative study that looks at a range of characteristics related to retention in engineering will be done, and the results analyzed using the theoretical frameworks of social cognitive career theory and self-efficacy.
Title 3-D Osteochondral Micro-tissue to Model Pathogenesis of Osteoarthritis
Description Osteoarthritis (OA), the most prevalent form of arthritis, affects up to 15% of the adult population and is principally characterized by degeneration of the articular cartilage component of the joint, often with accompanying subchondral bone lesions. Understanding the mechanisms underlying the pathogenesis of OA is important for the rational development of disease modifying OA drugs (DMOADs). While most studies on OA have focused on the investigation of either the cartilage or the bone components of the articular joint, the osteochondral complex represents a more physiologically relevant target as the disease ultimately is a disorder of osteochondral integrity and function. In this application, we propose to construct an in vitro 3-dimensional microsystem that models the structure and biology of the osteochondral complex of the articular joint. Osteogenic and chondrogenic tissue components will be produced using adult human mesenchymal stem cells (MSCs) derived from bone marrow and adipose seeded within biomaterial scaffolds photostereolithographically fabricated with defined internal architecture. A 3D-printed, perfusion-ready container platform with dimensions to fit into a 96-well culture plate format is designed to house and maintain the osteochondral microsystem that has the following features: (1) an anatomic cartilage/bone biphasic structure with a functional interface; (2) all tissue components derived from a single adult mesenchymal stem cell source to eliminate possible age/tissue type incompatibility; (3) individual compartments to constitute separate microenvironment for the “synovial” and “osseous” components; (4) cell-seeded envelopes to represent “synovium” and “endothelium”; (5) accessible individual compartments that may be controlled and regulated via the introduction of bioactive agents or candidate effector cells, and tissue/medium sampling and compositional assays; (6) compatibility with the application of mechanical load and perturbation; and (7) imaging capability to allow for non-invasive functional monitoring. The robustness and physiological relevance of the osteochondral microsystem will be tested on the basis of: (1) structural integrity and potential connectivity of the separate “synovial” and “osseous” compartments; (2) maintenance of distinct cartilage and bone phenotypes and the development of a histologically distinct osteochondral junction or tidemark; (3) applicability and tissue responsiveness to mechanical loading; and (4) imaging and analytical capabilities. The consequences of mechanical injury, exposure to inflammatory cytokines, and compromised bone quality on degenerative changes in the cartilage component will be examined in the osteochondral microsystem as a first step towards its eventual application as an improved and high-throughput invitro model for prediction of efficacy, safety, bioavailability, and toxicology outcomes for candidate DMOADs. This grant is held in the Department of Orthopaedic Surgery, University of Pittsburgh.
Source National Institutes of Health – National Center for Advancing Translational Sciences
Title A Regenerative Medicine Approach for TMJ Meniscus Restoration
Description This proposal seeks support to investigate the use of a biologic scaffold composed of extracellular matrix (ECM) as an inductive scaffold for the in vivo generation of a temporomandibular joint (TMJ) meniscus. Strong pilot studies indicate that this inductive template can stimulate the endogenous formation of a fibrocartilaginous disc that closely mimics the composition, structure, and mechanical properties of native disc material. Approximately 3% to 4% of the population seeks treatment for TMJ disorders; 90% of which are women. Approximately 70% of patients with TMJ disorders suffer from disc displacement; a fact that identifies the TMJ disc as a critical component in the cascade of events that lead to TMJ pathology. Spontaneous TMJ disc regeneration in vivo does not occur, and subsequent articulate surface degeneration can lead to the need for total joint replacement with marked negative consequences upon the quality of life. Development of a replacement disc would protect articulate joint surfaces, mitigate morbidity, and obviate the need for subsequent joint replacement.
Description This project involves a combination of in vitro and preclinical in vivo methods to develop and evaluate biologic surgical mesh materials. The work involves a combination of well described benchtop assays and animal models which can evaluate in vivo biocompatibility for novel surgical mesh materials.
Title Generation of an Artificial Intestine for the Treatment of Short Bowel Syndrome in Children
Description The clinical condition in which the body is unable to absorb food after significant loss of the intestine is called short bowel syndrome (SBS). While its true incidence is unknown, in the United States the condition affects over 5000 children, with an estimated 15,000 older patients requiring long-term home parenteral nutrition. SBS can be caused by loss of large portions of functioning intestine – such as occurs typically as a consequence of necrotizing enterocolitis (NEC), Crohn’s disease, or as a result of a birth defect in which the intestines do not develop normally. Because food cannot be adequately absorbed by the shortened intestine, nutrients must be administered directly into the circulation through a vein. Although this approach can supply adequate calories, children who receive nutrition directly into the circulation commonly suffer from intravenous catheter infections and severe liver toxicity, with mortality around 30%. Only about one third of patients with SBS can expect to be weaned from parenteral nutrition. The majority of children with short bowel syndrome require intestinal transplantation and if toxicity from the administered nutrition is severe enough, liver transplantation, as well. While the outcome after intestinal transplantation is improving, this procedure is limited by a lack of suitable donors and complications from immunosuppressive therapy. To address the difficulty of managing short bowel syndrome in children, Hackam and March propose constructing an artificial intestine using cultured intestinal stem cells from the recipient’s intestine that can grow on a synthetic 3-dimensional bioscaffold.
Title Continuous Red Blood Cell Production (Phase II)
Description A ready supply of safe and effective red blood cells is a critical component in the treatment of battlefield and civilian trauma. Conventional approaches to this challenge center around voluntary donation of whole blood, testing, processing, extended storage, shipping and therapeutic transfusion of blood or fractionated components. Many of the steps in this conventional approach are prone to error, are inefficient, and in some pathologies can be ineffective. We intend to transform this conventional approach by developing methods and systems to produce erythrocytes (and at a future time, other blood components) from readily available and expandable human non-embryonic progenitor cell populations in a safe, effective, robust and limited footprint in vitro manufacturing system.
Description The proposed research builds upon the pioneering work from the laboratory of Dr. Wagner in developing novel degradable biomaterials for a variety of soft tissue applications. Dr. Wagner’s group links polymer chemists, bioengineers and surgeons in this effort, and the proposed research takes advantage of this expertise. They have synthesized, characterized and processed a variety of biodegradable polymeric biomaterials and evaluated their performance for treating tissue insufficiency in vivo. The thermoplastic elastomeric materials proposed in this project have been synthesized and evaluated in the rat model in several different locations. Most of this in vivo work has involved the cardiovascular system for cardiac wall and blood vessel scaffolding. Other studies have evaluated application of the material in the abdominal wall and as subcutaneous implants for first level biocompatibility assessments. Dr. Wagner and Dr. Funderburgh have been collaborating over the past several years to begin translation of the Wagner lab’s materials expertise to the ophthalmic area.
Title Innovative In Vivo-Like Model for Vascular Tissue Engineering
Description The shortage of donor organs for transplantation suggests a need to develop engineered tissue transplants. Proper in vitro vascularization, a key prerequisite for the development of functional engineered tissue constructs, would enable adequate mass exchange, gas supply, and functional mediator exchange in high-density tissue cultures. The impact of physical and mechanical factors supporting endothelial differentiation has been investigated, but not in three-dimensional (3D) co-culture models. We propose to address this gap in cellular models and technology model systems, by analyzing neo-vascularization in an organ-like environment in vitro designed to mimic human organogenesis and that can vary physical conditions, such as flow- and pressure changes in the rhythm of the heart rate.
Title Basic and Clinical Studies of Cystic Fibrosis: Ex Vivo Model of Cystic Fibrosis
Description Cystic fibrosis (CF) affects approximately 30,000 individualsin the United States, causing an accumulation of thick, sticky mucus that adversely impacts normal mucociliary clearance. The lack of proper clearance predisposes patients to chronic pulmonary infections, injury to the conducting airways in the form of bronchiectasis and bronchiolitis obliterans, and ultimately can lead to respiratory failure. CF is the leading diagnosis in children that require lung transplantation. Considerable resources have been applied to the study of CF with the hope of developing a treatment or cure, but progress has not been as rapid as anyone would desire. In the current research environment, the only way to determine if a treatment strategy has an effect on airway function is to move from in vitro studies to clinical studies in patients, which poses a very high bar to acceptance. The primary purpose of this proposal is to develop a humanized ex vivo model of the CF airway as a means to investigate the effect of new therapies on function, including ion transport and mucociliary clearance. A bioreactor has been developed that is capable of simulating the conditions in the trachea during respiration. With the expertise from the P30, decellularized tracheas will be seeded with airway epithelial cells from patients with and without cystic fibrosis and the culture conditions will be optimized. Then testing strategies will be developed to assess airway epithelial cell function without disrupting the trachea construct and the impact of various known medical treatments on the cultures will be tested. Finally, airway tissue will be obtain from patients with and without CF, the tissue will be decellularized and seeded with airway epithelial cells to begin to understand if the composition and structure of airways in CF contributes to the dysfunction. The end result of this work will be a robust testing platform that will enable functional testing of the airway which will allow a deeper understanding of the pathogenesis of CF and more robust testing of new drug therapies.
Title Miniature Biofuel Cell from Gold Microfiber Electrodes
Description Evolving research on implantable sensors, drug-delivery systems and other power consuming implantable devices like pacemakers and insulin pumps requires the matching development of power sources that can be used together with the implantable device. A great deal of research performed on miniature, lightweight, long-lived batteries resulted in the development of the small lithium ion battery . The common battery is an energy source that contains reacting chemicals securely encased in an impermeable cell, and provides only the electrical leads to connect to devices. Current lithium iodide pace maker batteries have an open circuit voltage of 2.8 V, weigh about 13 g and have a relatively large volume of 5-8 ml.  Cardiac pacemaker battery design poses a number of special challenges including: the development of biocompatible materials; prevention of corrosion; preventing leakage of the contents; ensuring high reliability; and accurate determination of the end of the battery life. Many of these concerns and many of the inherent risks involved in battery replacement could be alleviated with a longer lasting biomimetic power source.
Title Drag-reducing polymers to curb breast cancer metastasis
Description Adhesion of circulating tumor cells to microvascular endothelial cells is key for extravasation of tumor cells and therefore an important step for tumor metastasis. There is growing evidence that systemic inflammation facilitates adhesion of circulating tumor cells to endothelial cells hence promoting metastasis and progression of cancer. It has been hypothesized that leukocytes enhance attachment of tumor cells to endothelial cells by creating formation of a tripartite linkage between these three different cell types. Presence of leukocytes in the tumor microenvironment also leads to local release of cytokines that further promotes junctional disruption of endothelial cells and extravasation of tumor cells. Current strategies to inhibit extravasation which involve molecular targeting of either a single adhesion receptor on tumor cells or a specific signaling pathway are therapeutically inefficient because of involvement of multiple adhesion receptors and signaling pathways in the extravasation process. In complete contrast to these currently envisioned strategies, we proposed a conceptually novel paradigm that hemodynamic perturbation that inhibits attachment of inflammatory cells to endothelial cells is an efficient way to impair tumor cell attachment to endothelium thereby reducing extravasation and metastasis. Systemic administration of so called drag reducing polymers (DRP – long-chain viscoelastic polymers that are non-toxic and blood-soluble) at nanomolar concentrations was shown to reduce/eliminate the near-wall cell-free layer naturally existing in microvessels (Fåhraeus effect) and to increase blood flow in microcirculation. DRP-induced occupation of the near-wall space by red blood cells and increasing of near-wall shear rates may inhibit leukocyte rolling and attachment to blood vessel wall which can drastically reduce inflammatory responses (demonstrated in animals implanted with biodegradable scaffolds) and transendothelial migration of tumor cells. We therefore propose a working postulate that “systemic administration of DRP is a novel interventional approach to reduce extravasation and metastasis of tumor cells” and this hypothesis will be tested by
Title Biodegradable, Thermoresponsive Hydrogels to Treat Ischemic Cardiomyopathy
Description Cardiac failure incurs a major economic and social burden on the United States populace, while also providing a distinct technical challenge since options for treating this condition remain highly limited. In ischemic cardiomyopathy ventricular wall thinning is coupled with dilation of the ventricular cavity. This remodeling process is associated with elevated ventricular wall stress that positively drives the thinning and dilation process towards end-stage heart failure. In the proposed work we will create novel designs for injectable biomaterials to bulk the thinning, post-infarct cardiac wall, reducing elevated wall stress, and potentially improving cardiac remodeling outcomes. The design objectives include synthesizing materials with tensile properties suitable for reducing wall stresses, degradation properties that maintain the hydrogel in the infarcted wall for a period of months during the remodeling process, and drug delivery properties that allow the controlled release of multiple growth factors that may stimulate beneficial cardiac remodeling. We will evaluate 3 distinct hydrogel designs with increasing complexity, utilizing both rat and porcine models of ischemic cardiomyopathy and a minimally invasive robotic technology (the HeartLander device) designed to effectively deliver the targeted hydrogel injections. The project specific aims are to:
Title ARM-IV Postdoctoral Program (Four Positions)
Description 1. “Rational Synthesis of Triggerably-Dissolvable Materials for Minimally Invasive Removal of WoundCAP Delivery Devices”
Mentors: Steven Little, Ph.D. and William Wagner, Ph.D.
Objective: The ultimate objective is to develop a robust, hollow fiber-based system (WoundCAP) to deliver regenerative growth factors to a wound site while including the means for minimally invasive removal/dissolution of the delivery system. We hypothesize that the resulting hollow fibers wound cap will have robust mechanical properties to maintain stable structures, but will dissolve rapidly upon application of a trigger, either a temperature change or enzyme solution injection.
Title A Multi-Center Group to Study Acute Liver Failure in Children
Co-Investigators Yoram Vodovotz
Description Our goal is to improve short- and long-term outcomes for pediatric acute liver failure (PALF) through a better understanding of patient phenotypes, reassessment of risk classifications, and associating early events to outcome at one year. We will integrate two research efforts (Vodovotz-3UO1DK-072146-05S1 and Roberts-1R21DK084201-01) currently collaborating with the PALF Study Group (NIH/NIDDK UO1 DK072146-05) which are (1) modeling PALF as a complex biological system using physiological and inflammatory biomarkers and (2) developing models to represent the liver transplant (LT) decisions in PALF. To examine our hypotheses that clinical, biochemical, genomic, proteomic, metabolomic, immunologic, and cytokine analyses in PALF can be used to accurately define phenotypes that respond favorably to directed therapy (e.g., immunomodulation) as well as predict disease progression, including potential for spontaneous recovery or risk of death, all of which will provide a platform on which computer/informatics-based (e.g., in silico) studies can inform the design and conduct of clinical trials, and evaluate the impact of therapeutic decisions, including LT; we propose these Aims: Aim 1: To comprehensively characterize PALF phenotypes utilizing traditional clinical, biochemical, diagnostic, and management profiles supplemented by immune, inflammatory and liver regeneration markers to identify factors that explain variations in outcomes for PALF phenotypes. Outcomes include survival, LT, neurocognitive function, health-related quality of life (HRQOL), depression and post-traumatic stress disorder (PTSD) 6 months and 1 year after enrollment. Aim 2: To model the dynamics of PALF within and between distinct phenotypes using serially collected clinical, physiological, and biomarker data. Statistical modeling techniques will be augmented with models used to represent complex biological systems to more accurately reflect the dynamic nature of PALF. The data and models will be utilized to create a computer-based or “in silico” analog of PALF to simulate interventional studies and to assess treatment, including LT decision processes and to estimate the impact of improved decision-making on organ allocation.
PI Thomas Gilbert
Title Cardiac Remodeling with Organ Specific Extracellular Matrix Scaffolds
Co-Investigators Kimimasa Tobita, Stephen Badylak
Description Improved materials for cardiac reconstruction of congenital defects and heart failure are needed. Current surgical approaches for cardiac reconstruction utilize synthetic materials that slow the progression of disease, but do not provide any contractile function and do not have the ability to grow with the patient. Recently, porcine urinary bladder matrix (UBM) has been used to repair myocardial tissue. The remodeled UBM contributed to regional function in both canine and porcine models, but did not fully restore myocardial tissue. Cardiac extracellular matrix (C-ECM) may promote faster reconstruction of functional tissue by providing a scaffold with a composition and architecture similar to the tissue that it is intended to replace. The proposed study will determine the morphologic and functional differences in cardiac remodeling after repair with C-ECM, UBM, and Dacron patches. Furthermore, the study will include analysis of the recruitment and fate of bone marrow derived progenitor cells at the site of remodeling.
An experienced interdisciplinary team consisting of biomechanical engineers, tissue engineers, physicians, and pathologists has been assembled to conduct these studies. A timeline for completion of these studies and quantitative criteria for success are provided.
PI Kacey Marra
Title 3D Culture of Adipose Tissue for Screening Obesity-related Drugs
Co-Investigators Joerg Gerlach, J. Peter Rubin, Donna Stolz
Description We have developed a novel, 3D bioreactor technology that permits the long-term culture of adipocytes, which is not possible using traditional 2D cell culture methods. In this study, we will utilize our technology to rapidly and effectively screen the effects of drugs on human adipose tissue function. We will examine the function of adipocytes in both obese and non-obese patients. One of the parameters we will study is cytokine/adipokine expression. With the bioreactor technology, we are able to rapidly and easily analyze daily expression of cytokines in the media. New drugs may target cytokine expression of adipocytes. It has been shown that involved cytokine behavior in obesity includes the increased expression of, but not limited to: MCP-1 (monocyte chemotactic protein-1, which can recruit macrophages to adipose tissue), TNF-α (tumor necrosis factor-α, a pro-inflammatory mediator secreted by macrophages), and IL-8 (interleukin-8, a pro-inflammatory cytokine secreted by macrophages). Also of interest is the expression of anti-inflammatory cytokines, such as IL-10 (interleukin-10). While these mediators have been examined using human and murine adipose tissue in 2D in vitro culture, improved experimental systems are necessary to allow the development of high throughput assays for drug discovery. Therefore, the specific aims of this proposal are to: 1) Isolate and characterize human adipose-derived stem cells from both male and female patients, age 40-60 years, (non-obese, vs. obese patients); 2) Develop a novel, multi-compartment, hollow fiber 3D perfusion bioreactor technology for ASC culture in 3D bioreactor; 3) Utilize the 3D perfusion bioreactor system as a tool to study the effects of drug therapies on adipose function. In summary, cell-cell contact in a 3D culture system mimicking natural adipose tissue represents an improvement over current petri-dish technologies aimed at developing high throughput assays for drug discovery.
Source The National Institutes of Diabetes and Digestive and Kidney Diseases
Description This collaborative research and development effort involves the characterization of various forms of extracellular matrix, especially porcine dermal derived extracellular matrix, for development and use as a biologic scaffold for pelvic floor reconstruction and general surgical use. The effort characterizes and identifies novel biomaterials for general surgical applications; particularly pelvic floor reconstruction and hernia repair. We will apply principles of regenerative medicine to principles of general surgery.
PI Alan J. Russell, Stephen F. Badylak, J. Peter Rubin, Bernard J. Costello, Prashant N. Kumta, Charles Sfeir, Paul Kemp
Title Limb Salvage and Regenerative Medicine Initiative
Co-Investigators Thomas Gilbert
Description This program will advance technologies that return wounded personnel to active duty, restore their limb, muscular, and skin form or function, and assist them in reclaiming independence, dignity, and self-confidence in the tasks of daily living. The program will fund rapid research, development and validation of innovative technologies to improve the clinical outcome of burn and blast injured personnel. Technology refers to integrated systems based on combinations of hardware, software, pharmaceuticals, biologics, and surgical methods. This initiative will advance medical technologies from their existing levels of maturation, through FDA trials and approval, to significantly improve upon current standard treatments for use by the Department of Defense, Veteran’s Administration, public health, and commercial health systems.
Description Regenerative medicine approaches for the reconstitution of missing or injured tissues and organs involves the use of scaffolds, cells, and bioactive molecules. The use of biologic scaffolds seeded with cells is a common approach and several applications have been successfully translated to clinical medicine including lower urinary tract, gastrointestinal tract, musculotendinous, and dermal skin regeneration. The principles that guide tissue remodeling and regeneration are only partially understood but the influence of biomechanical loading upon the remodeling process is accepted as an important variable. However, there is an almost complete absence of systematic, quantitative studies to determine the effect of this controllable factor upon tissue remodeling, especially tissues with a smooth muscle wall component.