Daniel J. Weiss - US grants

DESCRIPTION (Adapted from applicants' abstract) The candidate, an M.D., Ph.D. board eligible in Pulmonary and Critical Care Medicine, is strongly committed to a career in academic medicine with an emphasis on the molecular biology of lung injury and the development of strategies for gene therapy of lung disease. With the aid of this grant, he plans to develop further expertise in molecular biology and gene therapy techniques under the supervision of leaders in these fields. With the benefit of this experience, the candidate plans to establish himself as an independent investigator pursuing basic research, while keeping an active role in the practice of pulmonary medicine. The candidate proposes to study the role of perfluorocarbons (PFC) in augmenting gene delivery to lung. PFC are short fluorinated carbon chains with remarkable properties of gas solubility that can support effective gas exchange when instilled into the lung. PFC use provides a novel means of augmenting distribution of intratracheally co-administered drugs. A single recent report suggest that PFC may improve distribution of intratracheally administered adenoviral-vectors for gene transfer. Recent observations suggest the PFC can inhibit activity of macrophages and neutrophils following in vitro exposure. Using a model of PFC use in spontaneously breathing rodents, developed by the applicant, the role of PFC in augmenting gene delivery to lung will be investigated. The central hypothesis is that PFC use results in more widespread and uniform distribution, and in higher level of transgene expression. The specific aims are: 1) To evaluate PFC effect on adenoviral and liposomal-mediated transgene delivery to lung. 2) To investigate potential anti-inflammatory effects of PFC instillation in the lung. These studies are expected to help clarify the effects of PFC in augmenting gene delivery to lung and to evaluate possible anti-inflammatory effects of PFC instillation on gene delivery to lung. The long-term goal is to establish the scientific basis for therapeutic approaches using PFC in augmenting gene transfer to lung.

gene delivery system; lung; fluosol; animal colony; Primates; biotechnology;

DESCRIPTION (provided by applicant): The goal of this research is to gain insight into how language learners are able to form multiple representations when exposed to more than one language. Previous research has conflicted with respect to the age at which this ability is present (see Sebastian-Galles & Kroll, 2003). The proposed investigation will span infant and adult learners in order to understand whether the ability to form multiple representations is available to infants at 10 months of age and whether there are changes in processing over the course of development. Previous perceptual research investigating the development of bilingual language acquisition has typically focused on infants' abilities to discriminate between two different languages. The research proposed here employs a speech stream segmentation task that more directly assesses whether listeners are capable of forming multiple representations. Specifically, the experiments are designed such that participants must form separate representations for 2 artificial "languages" in order to correctly parse the languages and correctly identify the "words". Thus, this research also addresses a critical problem for the statistical learning literature. Namely, how can language learners correctly segment the input from multiple languages? If the statistics are combined across languages, incorrect segmentation of both languages could occur. A second goal of this research is to investigate the acoustic cues that may facilitate the formation of multiple representations. Language learners may face a difficult task of trying to determine when they are in the presence of multiple languages. Therefore, the task of the learner is to identify relevant features that denote a language change. In the proposed experiments, a series of cues will be manipulated in an effort to determine which features may be useful for cuing language learners to the presence of multiple languages. In sum, the proposed research will fill gaps in current knowledge regarding both bilingual language acquisition as well as statistical learning.

DESCRIPTION (provided by applicant): Stem cells obtained from bone marrow of adult mice can, following transplantation, localize to lungs of recipient mice and acquire phenotypic and functional characteristics of differentiated lung epithelial and interstitial cells. These findings raise the possibility that abnormal lung epithelium can be replaced or repopulated with normal functioning cells of bone marrow origin. This offers a new potential therapeutic approach for a variety of lung diseases including cystic fibrosis. However, the available data is mostly descriptive; the mechanisms by which marrow-derived cells are recruited to lung and participate in lung remodeling remain unclear. Lung injury increases the number of marrow-derived cells recruited to lung and these cells can participate in lung remodeling after injury. This suggests that substances released by injured or repairing lung may serve to recruit marrow-derived stem cells to lung and further induce phenotypic conversion into epithelial or interstitial cells. We postulate that soluble factors released by airway epithelial cells act to recruit adult marrow stem cells to lung and induce phenotypic conversion to airway epithelial cells. Further, release of potential soluble mediators will be increased in the setting of lung injury. In preliminary studies, we have found that IL-17, an inflammatory cytokine known to influence neutrophil chemotaxis, may mediate migration of mesenchymal stem cells (MSC) towards mouse airway epithelial cells in primary culture. We propose to further characterize the effects of IL-17 on recruitment and phenotypic conversion of adult MSC using targeted IL-17 over-expression in epithelial cells or by clocking IL-17 effects using either neutralizing antibody or MSC obtained from IL-17 receptor knockout mice. We also propose to investigate the hypothesis that IL-17 release is increased in CF epithelial cells and that this increases MSC recruitment and phenotypic conversion. These studies will serve as a basis for more detailed investigations into mechanisms of recruitment and phenotypic conversion of adult marrow stem cells into airway epithelial cells.

Adult marrow-derived cells participate in lung remodeling after injury. This suggests an exciting potential therapeutic approach for lung diseases including emphysema, a devastating and highly prevalent lung disease for which there remains no cure. However, emphysema is predominantly a disease of older patients. Studies evaluating repopulation of lung epithelium have been conducted in young mice. It is unknown whether lung remodeling with marrow-derived cells occurs in older lungs, particularly older diseased lungs. Soluble mediators released by lung epithelial cells play an important role in recruitment of adult marrow-derived cells to lung. However, little is known about whether this process is altered with aging. We hypothesize that release of mediators by epithelial cells and/or response to the mediators by the adult marrow-derived cells decreases with aging. This is a critical consideration if adult marrow- derived cells are to be utilized for emphysema. The current proposal will assess this hypothesis in vitro using primary cultures of lung epithelial cells and marrow-derived cells obtained from young and aged mice and in vivo assessing transplantation of adult marrow-derived cells in a mouse model of emphysema. Evaluations will include state of the art assessments of marrow-derived cell lung remodeling including sophisticated functional measurements of potential physiologic effects of lung remodeling by the marrow-derived cells. Our overall goal is to establish a scientific basis for the potential therapeutic use of marrow-derived cells for lung disease associated with aging and emphysema. (Lay Statement): Use of adult marrow-derived cells is a potential therapeutic approach for a number of lung diseases including emphysema. The proposed studies will investigate mechanisms by which adult marrow-derived cells might participate in repair of emphysematous lungs and provide important basic scientific information and a firm scientific basis for which to design future clinical trials.

[unreadable] DESCRIPTION (provided by applicant): [unreadable] [unreadable] Repair and regeneration of diseased lung with stem cells is an exciting potential therapeutic approach for a variety of lung diseases. Increasing information suggests that cells normally not resident in the lung can be recruited to the lung and participate in structural and functional repair and remodeling after injury. In parallel, there has been a surge in bioengineering studies investigating use of artificial matrices as framework for three-dimensional lung regeneration. The combination of these studies with those utilizing stem cells and/or cell therapies is a promising rapidly developing direction but one that is still in its infancy. These studies have been further paralleled by significant increases in understanding the molecular and cellular events by which stem and/or progenitor cells resident in the lung participate in both lung development and in repair and remodeling after lung injury. [unreadable] [unreadable] We held a conference at the University of Vermont in July 2005, "Adult Stem Cells, Lung Biology, and Lung Disease", sponsored by the NHBLI and Cystic Fibrosis Foundation, that brought together relevant investigators as well as interested junior faculty and students to debate and discuss issues in this rapidly moving field. This conference was very successful and resulted in a series of guidelines for basic and translation research to be utilized by both investigators and by funding agencies. The meeting also was the impetus for an NHBLI RFA "HL-07-003, Collaborative Studies on Lung Stem Cell [unreadable] Biology and Cell Based Therapy". [unreadable] [unreadable] As studies of stem cell and cell therapies for lung diseases continues to move at a rapid pace, we propose to again convene the relevant investigators as well as representatives from the NHLBI, FDA, and non-profit Respiratory Disease Foundations to again debate and discuss current issues. One area in particular to be discussed is the balance between basic and translational research and the role of clinical trials in this area. As in last summer's conference, junior investigators and students (graduate, post-doctoral, fellow) will be particularly targeted for inclusion in both conference discussions as well as [unreadable] in poster sessions. As a new feature, students will be able to compete for travel awards based on blinded review of poster abstracts. [unreadable] [unreadable] The conference is planned for July 2007 at the University of Vermont. Enthusiasm is already high among potential participants. We anticipate that this conference will again foster extensive discussion and debate and will significantly guide the directions taken in basic and clinical research of stem cells and cell therapies for lung diseases. [unreadable] [unreadable] [unreadable]

DESCRIPTION (provided by applicant): Stem Cells and Cell Therapies in Lung Biology and Diseases Repair and regeneration of diseased lung with stem cells is an exciting potential therapeutic approach for a variety of lung diseases. Increasing information suggests that cells normally not resident in the lung can be utilized to impair lung injry and also to induce repair and remodeling after injury. In parallel, there has been a surge in bioengineering studies investigating use of artificial and de-cellularized lung matrices as framework for three-dimensional lung regeneration. The combination of these studies with those utilizing stem cells and/or cell therapies is a promising and rapidly developing direction. These studies have been further paralleled by significant increases in understanding the molecular and cellular events by which stem and/or progenitor cells resident in the lung participate in both lung development and in repair and remodeling after lung injury. We have held four previous conferences at the University of Vermont: July 2005, Adult Stem Cells, Lung Biology, and Lung Disease, sponsored by the NHBLI and Cystic Fibrosis Foundation~ and in July 2007, 2009, and 2011 Stem Cells and Cell Therapies in Lung Biology and Disease, sponsored through the years by the NHLBI through an R13 conference grant as well as by the Alpha 1 Antitrypsin Foundation, Emory Center for Respiratory Health, LAM Treatment Alliance, Pulmonary Fibrosis Foundation, and the University of Vermont College of Medicine. These conferences have that brought together relevant leading international investigators as well as interested junior faculty and trainees to debate and discuss issues in this rapidly moving field. These conferences have been highly successful and have both stimulated the field and resulted in a series of guidelines for basic and translation research to be utilized by both investigators and by funding agencies. As studies of stem cell and cell therapies for lung diseases continues to move at a rapid pace, we propose to again convene the relevant investigators as well as representatives from the NHLBI, FDA, and non-profit Respiratory Disease Foundations to again debate and discuss current issues. One area in particular to be discussed is the balance between basic and translational research and the role of clinical trials, particularly as there have now been clinica trials of stem cells for pulmonary hypertension and for COPD. A particular focus for the upcoming conference will be on rising junior investigators and trainees and a new feature will be a session devoted to developing careers in this area. As always, junor investigators and trainees (graduate, post-doctoral, fellow) will be particularly targeted for inclusion in both conference discussions as well as in poster sessions. As a continuing feature, trainees will be able to compete for an increased number of travel awards based on blinded review of poster abstracts. The conference is planned for July 2013 at the University of Vermont. Enthusiasm is high among potential participants. We anticipate that this conference will again foster extensive discussion and debate and will significantly guide directions in basic and clinical research of stem cells and cell therapies for lung diseases.

DESCRIPTION (provided by applicant): There will never be enough donor lungs available to meet current and future transplantation needs. In contrast, de-cellularization of whole cadaveric lungs will result in an intact scaffold that can be re-cellularized with embryonic stem cells or with adult stem cells, including induced pluripotent stem cells (iPS) derived from individual patients and subsequently utilized for autologous transplantation. Notably, the de-cellularization process removes cellular antigens responsible for immune rejection and the de-cellularized lungs maintain native airway and alveolar architecture, extracellular matrix protein composition, and pulmonary vascular network. This will provide a potentially limitless supply of unrelated donor cadaveric lungs for use in diseases such as emphysema and other diseases for which there is currently no effective cure. Our preliminary data demonstrates that de-cellularized mouse lungs can be re-cellularized with both adult and embryonic stem cells. Further, the de-cellularized lung preparations can be assessed by both histologic and functional outcomes including lung mechanics, surfactant production, vascular perfusion, and epithelial barrier function, as the lungs re-cellularize. Most importantly, preliminary data demonstrates that the lungs can be surgically re-implanted in animal models. These data provide a firm platform for the proposed multi-institutional collaborative studies in which state-of-the-art bioengineering techniques will be utilized to develop optimal methods for growing functional lung tissue in de-cellularized lungs, including cadaveric human lungs, and to devise optimal approaches for surgical implantation. The central goal of this proposal is therefore to utilize a comprehensive multidisciplinary multi- institutional approach for generation, functional characterization, and subsequent surgical implantation of viable lung tissue produced using stem cells in the de-cellularized lungs. This will be accomplished in the following two Specific Aims: 1) To optimize conditions for development of functional three dimensional lung tissue from embryonic and/or induced pluripotent stem cells grown in de-cellularized mouse lungs. 2) To develop strategies for successful in vivo implantation and functional assessment of re- cellularized lungs. PUBLIC HEALTH RELEVANCE: There will never be enough donor lungs available to meet current and future transplantation needs. In contrast, de-cellularization of whole cadaveric lungs will result in an intact scaffold that can be re-cellularized with stem cells (iPS) derived from individual patients and subsequently utilized for autologous transplantation. Our preliminary data demonstrates that de-cellularized mouse lungs can be re-cellularized with both adult and embryonic stem cells. The proposed multi-institutional collaborative studies will utilize state-of-the-art bioengineering techniques to develop optimal methods for growing functional lung tissue in de-cellularized lungs, including cadaveric human lungs, and to devise optimal approaches to surgically implant the re-cellularized lungs. This will provide a potentially limitless supply of unrelated donor cadaveric lungs for use in diseases such as emphysema, pulmonary fibrosis, and others for which there is currently no effective cure.

DESCRIPTION (provided by applicant): Despite advances in the symptomatic treatment of emphysema, the prevalence of this devastating lung disease is increasing worldwide and there remains no cure save for lung transplantation. We propose that novel tissue engineering approaches utilizing embryonic stem cells (ESCs), adult mesenchymal stem cells (MSCs), or induced pluripotent stem cells (iPS) cultured in three-dimensional culture matrices can regenerate functional lung tissue for replacement of emphysematous lung tissue. We have found that MSCs impregnated into de-cellularized mouse lungs re-cellularize both airways and parenchymal lungs regions and acquire phenotypic markers of type 2 alveolar epithelial cells in the parenchymal lung regions. These findings raise the possibility that embryonic or adult stem cells cultured in de-cellularized lungs can be utilized to engineer new lung tissue ex vivo and that this might be a therapeutic strategy for regenerating new alveoli in emphysematous lungs. Further, lung cells are subjected to cyclic stretch and other forces during normal breathing. We have found that cyclic stretch of cultured MSCs specifically induces expression of lung epithelial proteins while decreasing expression of markers of other cell types such as fibroblasts or muscle cells. These preliminary studies raise the possibility that specific manipulation of the culture environment by applying mechanical forces reminiscent of those found in normal lung can further promote development of functional lung tissue from embryonic or adult stem cells. The influences of 3-dimensional culture and of cyclic stretch, in combination with a specific airways growth medium, on development of lung cells from MSCs, ESCs, and iPS will be explored and defined in this proposal. These studies will provide a firm scientific basis for lung tissue engineering utilizing embryonic and adult stem cells as a possible therapeutic approach for emphysema and other lung diseases. PUBLIC HEALTH RELEVANCE: Chronic obstructive pulmonary disease (COPD), the fourth most common cause of death worldwide, remains a devastating fatal lung disease that is one of the only major diseases increasing in prevalence and for which there is no cure save lung transplantation. A new cell-based therapy approach is suggested by our recent work demonstrating that adult mesenchymal stem cells cultured in three-dimensional scaffolds may form viable lung tissue for potential use in regenerating new lung in emphysema. The focus of the current proposal is to further explore whether 3 dimensional scaffolds as well as mechanical stretch may be used to direct generation of functional 3- dimensional lung tissue from mesenchymal stem cells as well as from embryonic and induced pluripotent stem cells. These studies will provide a firm scientific basis for future translational and clinical trials of stem cells for treatment of emphysema.

DESCRIPTION (provided by applicant): The overall goal of the present grant application is to understand how a naive learner collects distributional information from the environment and makes an implicit decision that the corpus of input contains either a single structure or multiple structures. Mature learners are incredibly facile at interpreting information in a context-specific manner, thereby partitioning the input into two or more sub-structures. We will investigate this question of context-specific statistical learning by studying two types of naove learners - human infants and tamarin monkeys - as well as mature adults. The specific objective of the proposed research is to determine whether and how infants learn that there are multiple patterns of information embedded in streams of speech, or that there are multiple words that refer to the same object, and to determine whether context-specific statistical learning has species-specific biases. Two types of experimental designs will be used to study context-specific statistical learning. The first uses a single change in the underlying structure. A variety of contextual cues will be introduced to signal that the underlying structure has undergone a change, and the dependent measure is whether the learner has acquired the first, the second, both the first and the second, or neither structures. The second design uses two alternating structures that are signaled by a variety of stimulus cues to partition the two underlying structures. It is important to note that in both of these designs, if the learner aggregates the structural information across the entire corpus, rather than partitioning the corpus into two subsets, no learning is possible. Thus, these designs test the ability of the learner to extract the contextual cues that partition the input into subsets. The implications of the proposed studies are fundamental to any theory of learning, but particularly to the kind of implicit (passive exposure) statistical learning that is thought to characterize much of early human development in many domains. Infants must learn - by a combination of sensitivity to distributional patterns and innate biases - that patterns of information are context-specific, as in the case of bilingualism. Our proposed experiments will extend our recent studies of human adults by determining (a) whether infants show the same pattern of learning biases (primacy effects) and context-sensitivity (to talker voice), (b) whether tamarin monkeys show these same biases and context effects, and (c) what the limits of context-specific statistical learning are in human adults and infants in both word segmentation and referential tasks. PUBLIC HEALTH RELEVANCE: Language development is one of the hallmarks of the human species, yet it is difficult to study because of the huge variation in early exposure to different amounts of linguistic input. The use of artificial languages that are acquired in the lab over a few hours provides a window on the mechanisms of language development. We will study language learning in the lab to gain a unique perspective on how the infants and adults learn the patterns of words in streams of speech and contrast this with performance in nonhuman primates. These studies will not only reveal a basic mechanism of language learning, but also establish benchmarks against which language delay can be compared. Moreover, understanding the mechanisms that lead to successful acquisition in normal infants and adults can help to identify loci of language disorders and design methods for remediating disorders.

DESCRIPTION (provided by applicant): There will never be enough donor lungs available to meet current and future transplantation needs. In contrast, de-cellularization of whole cadaveric lungs will result in an intact scaffold that can be re- cellularized with adult stem cells, including induced pluripotent stem cells (iPS), derived from individual patients and subsequently utilized for autologous transplantation. Notably, the de-cellularization process removes cellular antigens responsible for immune rejection and the de-cellularized lungs maintain native airway and alveolar architecture, extracellular matrix protein composition, and pulmonary vascular network. This will provide a potentially limitless supply of unrelated donor cadaveric lungs for use in emphysema and other diseases for which there is currently no effective cure. However, there are several fundamental questions to be addressed for use of human lungs as scaffolds. Key among these is the reliability and reproducibility of the de-cellularization and re-cellularization processes. Unlike homogenous laboratory mice, donor human lungs will come from patients of different ages and from a variety of clinical and disease backgrounds, including a history of smoking, which might influence the nature of the scaffold following de-cellularization or the re-cellularization process itself. Therefore this proposal will focus on determining key differences between de-cellularized lung scaffolds originating from different donors and on discovering key environmental conditions that determine successful re-cellularization of lung scaffolds with human mesenchymal stromal cells (hMSCs) and induced pluripotent stem cells (iPS). Our preliminary data demonstrates that human lung can be successfully de-cellularized and studied by a variety of histological and functional assessments including lung mechanics, surfactant production, vascular perfusion, and epithelial barrier function, as the lungs re-cellularize. Further, preliminary data demonstrates that human mesenchymal stromal cells (hMSCs) and human alveolar epithelial cells (A549 cells) can be successfully inoculated and grown in de-cellularized human lung. These data provide a firm platform for the proposed two Specific Aims. 1) To determine key differences between de-cellularized lung scaffolds obtained from different donors. 2) To optimize conditions for growth and differentiation of hMSCs, and human iPS cells into functional three dimensional lung tissue when inoculated into de-cellularized human lung slices and apply this technology to whole de-cellularized human lungs. (End of Abstract)

? DESCRIPTION: Despite exciting recent progress in ex vivo lung bioengineering utilizing decellularized whole lung scaffolds, a number of hurdles remain. These include schemes for functional recellularization with combinations of appropriate cell types, long term maintenance of recellularizing lungs, and incomplete understanding of optimal vascular perfusion and cyclic mechanical stretch influences on proliferation, differentiation, and appropriate function of cells inoculated into the scaffolds. Further, most progress to date has been made in rodent models. This in part reflects the relative difficulties in working with human as compared to rodent lungs including a more limited supply of human lungs and the practical aspects of handling larger more cumbersome lungs. This has hampered progress in assessing the multiple combinatorial conditions that must be evaluated for development of functional human lung tissue. To address these hurdles, we have developed novel and innovative techniques for studying recellularization of acellular human lung scaffolds. These include; a) More optimal detergent- based decellularization protocols; b) Infrared perfusion imaging and sophisticated mass spectrometric assessment of residual scaffold proteins; and c) Novel high throughput approaches for studying decellularized human lungs. This latter technique involves dissection of multiple small 1cm3 segments, each with a cannulatable bronchovascular bundle, from whole decellularized lungs. We have further developed a flexible artificial pleural coating for use with these segments that allows study of ventilation and perfusion of the recellularizing human lung segments. We have also developed a functional assay for surfactant production by assessing changes in lung mechanics in recellularizing scaffolds. Using these techniques, we have made significant advances in recellularizing acellular scaffolds produced from normal and diseased rodent, pig, primate, and human lungs. In particular, we have found significant effects of perfusion and of cyclic mechanical stretch on survival and differentiation, respectively, of pulmonary vascular endothelial cells and of type 2 alveolar epithelial cells in the scaffolds. The goal of the current application is to continue to develop advanced translational applicable schemes for recellularization of human lung scaffolds. Focus will be on combinations of relevant human lung cell types, including endogenous airway progenitor cells and iPS-derived lung epithelial cells (Specific Aim 1), developing appropriate perfusion schemes and perfusates for long term maintenance or recellularizing scaffolds (Specific Aim 2), and developing optimal mechanical ventilation schemes that will maximize influence of cyclic mechanical stretch on development of functional lung tissue (Specific Aim 3). Importantly, we have built an outstanding collaborative team with which to achieve these goals.

? DESCRIPTION (provided by applicant): Stem Cells, Cell Therapy, and Bioengineering in Lung Biology and Diseases Cell therapy and bioengineering approaches for repair and regeneration of diseased lungs is a rapidly progressing field with exciting potential therapeutic applications for a variety of lung diseases. Increasing information suggests that cells normally not resident in the lung can be utilized to impair lung injury and also to induce repair and remodeling after injury. In parallel, there has been a surge in bioengineering studies investigating use of artificial and decellularized lung matrices as framework for three-dimensional lung regeneration. The combination of these studies with those utilizing stem cells and/or cell therapies is a promising and rapidly developing direction. These studies have been further paralleled by significant increases in understanding the molecular and cellular events by which stem and/or progenitor cells resident in the lung participate in both lung development and in repair and remodeling after lung injury. We have held five previous conferences at the University of Vermont: July 2005, Adult Stem Cells, Lung Biology, and Lung Disease, sponsored by the NHBLI and Cystic Fibrosis Foundation; and in July 2007, 2009, 2011, and 2013 Stem Cells and Cell Therapies in Lung Biology and Disease, sponsored through the years by the NHLBI through an R13 conference grant as well as by the Alpha 1 Antitrypsin Foundation, Emory Center for Respiratory Health, European Respiratory Society, LAM Treatment Alliance, Pulmonary Fibrosis Foundation, and the University of Vermont College of Medicine. These conferences have brought together relevant leading international investigators as well as interested junior faculty and trainees to debate and discuss issues in this rapidly moving field. These conferences have been highly successful and have both stimulated the field and resulted in a series of guidelines for basic and translation research to be utilized by both investigators and by funding agencies. As studies of stem cell, cell therapies, and bioengineering for lung diseases continues to move at a rapid pace, we propose to again convene the relevant investigators as well as representatives from the NHLBI, FDA, and non-profit Respiratory Disease Foundations to again debate and discuss current issues. A continued focus for the upcoming 10th anniversary conference will again be on rising junior investigators and trainees, particularly women, under-represented minorities, and disabled investigators. As always, junior investigators and trainees (graduate, post-doctoral, fellow) will be particularly targeted for inclusion in both conference discussions as well as in poster sessions. As a continuing feature, trainees will be able to compete for an increased number of travel awards based on blinded review of poster abstracts. The conference is planned for July 2015 at the University of Vermont. Enthusiasm is high among potential participants. We anticipate that this conference will again foster extensive discussion and debate and will significantly guide directions in basic and clinical research of stem cells and cell therapies for lung diseases.

Abstract: Stem Cells, Cell Therapies, and Bioengineering in Lung Biology and Diseases Repair and regeneration of diseased lung with stem cells or bioengineered tissue are exciting potential therapeutic approaches for a variety of lung and airway diseases. Increasing evidence suggests that cells which are not normally resident in the lung can be utilized to induce repair and remodeling after injury. In parallel, there has been a surge in bioengineering studies investigating use of artificial and acellular lung matrices as scaffolds for three-dimensional lung or airway regeneration. The combination of these studies with those utilizing stem cells and/or cell therapies is a promising and rapidly developing research area. These studies have been further paralleled by significant increases in understanding the molecular and cellular events by which stem and/or progenitor cells resident in the lung participate in during lung development as well as in normal and pathologic repair and remodeling after lung injury. We have held six previous conferences at the University of Vermont in 2005, 2007, 2009, 2011, 2013, 2015. These conferences have brought together leading international investigators with junior faculty and trainees to debate and discuss issues in this rapidly moving field. These conferences have been highly successful and have both stimulated the field and resulted in a series of guidelines for basic, translational, and clinical research to be utilized by both investigators and by funding agencies. As studies of stem cell and cell therapies for lung diseases continues to move at a rapid pace and the field explores how to best translate these approaches, we propose to again convene the relevant investigators as well as representatives from the NHLBI, FDA, and leading non-profit Respiratory Disease Foundations to debate and discuss current issues. One area in particular to be discussed is the balance between basic and translational research and the role of clinical trials, particularly as there have now been clinical trials of stem cells for and number of conditions including ARDS, BPD, COPD, pulmonary fibrosis, pulmonary hypertension and for sepsis/septicshock. A particular focus for the upcoming conference will be on rising junior investigators and trainees and how to best further develop careers in this area. As always, junior investigators, trainees, and investigators from underrepresented minority groups will be targeted for inclusion in conference presentations, discussions and poster sessions. Trainees will be able to compete for an increased number of travel awards based on blinded review of submitted abstracts. The conference is planned for July 2017 at the University of Vermont. Enthusiasm is high among potential participants. We anticipate that this conference will again foster extensive discussion and debate and will significantly guide directions in basic, translational, and clinical research of stem cells, cell therapies, and bioengineering approaches for lung diseases.

In contrast to left ventricular assist devices used in end stage cardiac disease patients, there are few available bridging devices available for end stage lung disease patients. Extracorporeal membrane oxygenation (ECMO) devices have a significant role in short term acute neonatal respiratory diseases and a more limited role in acute adult respiratory diseases. However, ECMO requires hospitalization in critical care units and specialized health care providers. As such, it is not a practical or cost effective option for long term bridging to lung transplant. New innovative cost-effective easily implementable technologies are desperately needed. We have extensively studied ex vivo lung bioengineering with focus on de- and recellularization of mammalian lungs. This includes developing potential transplantation strategies creating ex vivo autologous lungs from decellularized cadaveric or failed donor lungs recellularized with cells obtained from the eventual transplant recipient. This is a powerful rapidly evolving promising approach. However, a number of significant hurdles remain including recapitulating appropriate gas exchange and respiratory physiology. As opposed to mammalian lungs, avian lungs are static multilayered structures in which gas exchange occurs by cross current exchange and is more efficient than the more complex ventilation required by mammalian lungs. As such, avian lungs could provide a potentially novel and effective bioscaffold for use as lung assist devices and possibly also in transplantation schemes. The central hypothesis of this proposal therefore is that decellularized avian lungs, recellularized with human lung epithelial, endothelial, and stromal cells, and subsequently with relevant lung stem and progenitor cells, will therefore provide a novel and more powerful gas exchange unit than recellularized mammalian lungs. The recellularized avian lungs could be utilized as independent hospital (ICU)-based units, comparable to ECMO, portable units, comparable to portable dialysis devices or insulin pumps, or as gas exchange units implantable into the thoracic cavity. These objectives will be investigated in the following Specific Aims: 1. To fully characterize de- and recellularization of representative avian lungs. 2. To develop initial technologies for novel Avian Lung Assist Devices (ALAD) incorporating recellularized avian lungs that could be potentially utilized for independent, portable, or implantable lung assist devices. The aims will be pursued in collaboration between lung biologist Daniel Weiss and engineers Patrick Lee and Dryver Huston. The intellectual property and technology developed from these studies will be subsequently licensed for further industry-based development.