Blood vessels via reprogramming of peripheral blood cells (funded by the FWF / Herzfelder Stiftung)
Today’s vascular replacement materials are associated with several limitations, including thrombogenicity, calcific degeneration and lack of growth. The Weber group and others have previously shown the feasibility to engineer functional bioengineered blood vessels, heart or venous valves in vitro based on autologous cell systems and rapidly degrading polymer materials. However, in spite of the promising experimental results, no clinical trials based on the in vitro tissue engineering approach have been initiated so far due to the lack of an appropriate cell source. Initially, mature vascular-derived cell shave been isolated from patients, which requires the harvest of intact donor tissue. In the attempt of establishing less invasive cell sources, mesenchymal stem cells (MSCs) have been isolated. In a series of studies the feasibility of using MSCs for the vascular tissue engineering approach has been demonstrated. However, also these cells are associated with significant limitations: Fetal adnexal tissues are limited to prenatally diagnosed defects only and postnatal MSCs also require additional surgical interventions. In addition, MSCs have been used to generate the interstitial component of vascular constructs. However, derivation of endothelial cells from these sources in sufficient quantities seems difficult. On the contrary, peripheral blood-derived mononuclear cells (PBMCs) would represent an ideal cell source for vascular tissue engineering as they are easily and repeatedly accessible in large numbers. Direct isolation of all vascular cell phenotypes in sufficient amounts required for tissue engineering from peripheral blood hasn’t been feasible so far. The recently emerged technology of “induced pluripotent stem cells” (iPSCs) may have the potential to overcome this hurdle as they would allow for the generation of autologous patient-specific cells with a desired (vascular) phenotype. Therefore, the presented project aims at generating tissue engineered vascular replacement constructs from vascular cells that were differentiated out of PBMC-derived iPSCs. After culturing the constructs under dynamic flow and pressure conditions, we will evaluate their biomechanical properties as well as the extracellular matrix composition and compare them with constructs generated from vascular control cells. Finally, the engineered constructs will be evaluated in a murine animal model to confirm in vivo functionality of the engineered tissues. This approach would allow for using peripheral blood as a single autologous cell source for in vitro engineering of large diameter vascular grafts in the future.
Colloborators
- Daria Marolt (Ludwig Boltzmann institute for experimental and clinical traumatology, Vienna, Austria)
- Melanie Generali (Institute for Regenerative Medicine, University and ETH Zurich, Switzerland)
- Reiner Wimmer (Institute of Molecular Biotechnology, Penninger group, Vienna, Austria)
- Stem Cell Core Facility, Institute of Molecular Biotechnology, Vienna, Austria
- Dominik Wiedemann (Cardiac Surgery, Medical University of Vienna, Austria)
- Bernhard Winkler (Cardiac Surgery, Hospital North, Vienna)
- Jaroslav Slamecka (Stem Cell Translation Lab, National Center for Advancing Translational Sciences (NCATS) / NIH; Bethesda, USA)
Cell Cycle. 2016;15(2):234-49. Slamecka J, Salimova L, McClellan S,
van Kelle M, Kehl D, Laurini J,Cinelli P, Owen L, Hoerstrup SP,
Weber B. Non-integrating episomal plasmid-based reprogramming
of human amniotic fluid stem cells into induced pluripotent stem
cellsin chemically defined conditions.
Proteomic analysis of human mesenchymal stromal cell secretomes: Towards induction of therapeutic angiogenesis (funded by the CABMM-grant and industry collaborations)
Human mesenchymal stromal cells (hMSCs) are a heterogeneous population of non-clonal cellscontaining a multipotent stem cell fraction. Since their introduction, the number of pre-clinical and first clinical studies has continuously increased over the last decades, with more than 850 clinical trials being performed so far. Importantly, it has become evident that functional benefits exerted by hMSCs upon transplantation are mainly due to the secretome of these cells, promoting cytoprotection, angiogenesis,and tissue repair. The angiogenic potential is of particular interest for the treatment of ischemic diseases (e.g. chronic ischemicwounds or myocardial infarction) in order to reinstall perfusionand thereby limitingtissue damage. However, hMSC secretomes isolated from different tissue sources have shown dissimilarities with respect to their angiogenic profile. This project aims at defining and investigating the hMSC source with the strongest angiogenic potential. This involved a systematic comparison of hMSCs isolated from different tissue sources, such as cells isolated from the bone marrow (hBMSC), the umbilical cord Wharton’s jelly (hWJSC), the adipose tissue (hADSC) or the skin (hSMSC).Cells isolated from these sources will besystematically compared on their proteomic profile and functional responses in vitro and in vivo (using murine Matrigel plug assays). These systematic analyses may have implications on the selection of hMSCs for future clinical studies
Collaborators:
- Debora Kehl (University of Zurich, Switzerland)
- Benjamin Gantenbein (University of Bern, Switzerland)
- Bernhard Winkler (University of Bern, Switzerland and KAV/Vienna, Austria)
Nature Partner Journal Regenerative Medicine (npj Regenerative Medicine); 2019,16;4:8. Kehl D, Generali M, Mallone A,
Heller M, Uldry AC, Cheng P, Gantenbein B, Hoerstrup SP, Weber B.
Proteomic analysis of human mesenchymal stromal cell secretomes:
a systematic comparison of the angiogenic potential.
In vitro modeling of human arterio(lo)sclerosis: from pathological findings to pharmaceutical interventions
Originally described by Otzet Fernando Martorell in 1945, the arteriolosclerotic ulcer of Martorell (ASUM) represents an important differential diagnosis of leg ulcers. Even if the exact prevalence of ASUM remains to be elucidated, recent reports estimate that it accounts for up to 15% of all patients with leg ulcers in specialized wound clinics. Apart from split thickness skin grafting, no effective pharmacological treatment has been reported so far. The clinical differential diagnosis of ASUM is often highly challenging given the lack of clearly affirmative instrument-based diagnostic criteria. As a result, the differential diagnosis of ASUM harbors the risk of under- or mis diagnosis. This isparticularly disconcerting when considering the reports of misdiagnosis of ASUM with necrotizing vasculitis or pyoderma gangraenosum potentially resulting in life threatening complications. Since Martorell’s first description several reports on histological findings have been publishedand histological investigation of deep, periulcerative biopsy specimens evolved into an ancillary element of its differential diagnosis. However, so far no generally accepted, validated histological criteria of ASUM are available and the diagnostic value of histological findings in these patients remains to be content of controversial scientific discussions. Therefore, this study aims at the systematic histological as well as immunohistochemical analysis of deep skin biopsies of patients diagnosed with calcific arteriolopathies, in particular patients with ASUM. The findings will be systematically compared to patients suffering from non-arteriolosclerotic ulcers in order to investigate the discriminative power of the obtained findings. These results may serve as a basis for the development of histological “minimal diagnosticcriteria” compatible with the diagnosis of ASUM, which would significantly facilitate the differential diagnosis of this potentially under diagnosed disease in the future. In addition, these results serve as basis for developing an in vitro vascular disease model to study the pathophysiology of calcific arteriolopathies in more detail.
Collaborators:
- Jürg Hafner and Barbara Meier (Dermatology Department, University Hospital Zurich, Switzerland)
- Helmut Beltraminelli (Dermatology Department, University Hospital Bern, Switzerland)
- Philipp Tschandl (Department of Dermatology, Medical University of Vienna, Austria)
- Notburga Gierlinger (Institute for Biophysics, University of Natural Resources and Life Sciences, Vienna)
- Jonas Brugger (CeMSIIS − Center for Medical Statistics, Informatics and Intelligent Systems)
Biomaterials. 2018;150:49-59. Mallone A, Stenger C, Von Eckardstein A, Hoerstrup SP, Weber B. Biofabricating atherosclerotic plaques: In vitro engineering of a three-dimensional humanfibroatheroma model.
Further ongoing research projects:
- Protecting vascular barrier function across discipline and disease boundaries (Co-PI: Klaudia Schossleitner), wwtf
- Multimodel skin ulcer imaging (MUSE Project 2020, together with the Center for medical Physics and Biomedical Engineering Medical University of Vienna)
- Bioengineered vascular grafts for the in vitro investigation of coagulation disorders (together with the Department of Hematology Medical University of Vienna)
- Differential computational surface modeling of cutaneous ulcerations