Leitung Prof. Dr. med. C. Blume
Post Docs: Dr. R. Jonczyk, Dr. S. ThomsDoktoranden: Kathrin von der Haar, Xenia Kraus, SebastianHeene, Nina Wichert
Main Research Topics
Labeling / Conditioning of Mesenchymal Stem Cells for Tissue Engineering
In recent years, stem cell therapy has become more prevalent in the treatment of injuries and diseases. In this case, adult human mesenchymal stem cells are a promising cell type, since they be used as an autologous cell source and their use bears a low immunological risk in comparison with non-autologous transplanted cells in the recipient. However, in some clinical trials, cancer has occurred in stem cell therapy. Whether this is directly related to the stem cells transplanted, or whether tumor development occurs coincidentally, is uncertain. To find out, the stem cells must be labeled before transplantation to be clearly identified after transplantation. For this purpose, a labeling method based on nonsense DNA was developed, which in particular does not adversely affect the biological phenotype of stem cells and their potency to differentiate. For gene transfer of the label into the cells, the method of cell transfection is crucial. Transient transfection by means of electroporation led to an efficient and stable gene expression over several months and it did - in contrast to lentaviral transduction - not alter cell biology.
Tissue engineering is a rapidly growing sector in the field of future-oriented medicine and offers enormous potential in the development of bioartificial vascular prostheses, which is becoming more and more important in a rapidly aging society. One of the major problems in development is the isolation and cultivation of endothelial cells under the aspect of an autologous transplantation. However, recent studies show that human mesenchymal stem cells isolated from the adipose tissue of patients (hASCs, cooperation with the Department of Plastic Surgery of MHH) have approaches to differentiate into an endothelial direction and also positively influence the differentiation of immature endothelial cells into capillaries. We have therefore developed a protocol for the targeted use of stem cells in co-culture with endothelial cells. In particular, the cultivation parameters hypoxia and shear stress play an important role in the induced secretion of pro-angiogenic markers. In parallel, we isolate endothelial progenitor cells from the peripheral blood (cooperation with the blood bank of the MHH) and optimize their extracorporeal expansion and development into a confluent cell layer on scaffold materials for a vascular biohybrid graft. Flow cytometric analyses of specific cell subgroups and selective sub-cultivation play a major role here.
In the field of bioprinting, we work closely together with the "Blume" (eNIFE) working group using an BioX bioprinter (Cell-Ink.). Novel biodegradable polymers are tested as scaffold material and printed in fine structures, coated with native extracellular matrix proteins and populated with endothelial cells. This occurs in cooperation with the AG of Ulrike Böer, PhD and Mathias Wilhelmi, MD here in the NIFE and relates to their scientific work on decellularized animal arteries. In parallel, these scaffolds are also produced by "porogen leaching" from PLLA / PLGA and other biodegradable polymers, which are used for the targeted colonization of cell co-cultures from MSCs and endothelial cells for the maturation of capillary networks.
We developed a bioreactor system for the cultivation of a vascular graft with wireless control, pulse waves and ultrasound monitoring as well as sensors for temperature, pH and glucose.
For the provision and cultivation of a "vascular graft" (bioartificial vascular graft) to be translated to the patient, our working group also developed and optimizes a functional bioreactor in cooperation with the AG Blume (eNIFE). In contrast to existing systems, this also regulates the differentiation process of the growing graft and controls the cultivation conditions. For this purpose, sensor systems for pH, temperature, glucose, pressure in the pulsatile circulation system etc. were adapted and a non-contact monitoring via ultrasound was established. The bioreactor was already awarded the VDI (Verein Deutscher Ingenieure) prize in 2018.
Another task of the working group is biotesting. Biotesting means the screening of different pharmacologically active substances with regard to their effect on the proliferation behavior as well as their toxicity to human primary cells as well as cell lines. For the screening, established assays (CTB, MTT, ECIS, Apo ONE) are used as well as new methods are established, which include more detailed study-specific questions. These include the determination of toxicity of modern immunosuppressants in established 3D spheroid systems. Our results explain, for example, the clinically observable endothelium-destroying effect of the calcineurin inhibitor tacrolimus even under controlled clinical conditions. Also newly processed implant materials such as special precision-engineered titanium platelets for use in dental implants are tested with regard to the effective adhesion of human cell systems and for optimal osseointegration e. g. of dental implants (cooperation with the Institute for Manufacturing Technology and Machine Tools, Prof. B. Denkena and with the AG Prof. M. Stiesch in the NIFE). Furthermore, two PhD students at the Institute of Technical Chemistry in the Nordstadt work on the development of pont of care diagnostic test systems such as lateral flow assays for kidney transplant rejection based on sensitive antibodies and aptamers. This EFRE-(Europäischer Fond für regionale Entwicklung) funded project is networked with the Institute of Transfusion Medicine and the Department for Nephrology at the MHH.
von der Haar, K., Jonczyk, R., Lavrentieva, A., Weyand, B., Vogt, P., Jochums, A., Stahl, F., Scheper, T., Blume, C. (accepted 2019): Electroporation: A sustainable and cell biology preserving Cell Labeling Method for adipogenous Mesenchymal Stem Cells, BioResearch
Thoms, S., Witt, M., Jonczyk, R., Scheper, T., Blume; C. ( submitted 2019): Dynamic-hypoxic conditioning of adipose tissue-derived mesenchymal stem cells and co-culturing with human umbilical vein endothelial cells favors endothelial network formation, Tissue Engineering and regenerative medicine.
Thoms, S., Ali, A., Jonczyk, R., Scheper, T., Blume; C. (2018): Adverse effects of tacrolimus on stability of endothelial cells in spheroids and angiogenesis – toxicity testing in a 3 D cell culture approach, Toxicology in Vitro.
Maschhoff, P.; Heene, S.; Lavrentieva, S.; Hentrop, T.; Leibold, C.; Wahalla, M.-N.; Stanislawski, N.; Blume, H.; Scheper, T.; Blume, C. (2017): An intelligent bioreactor system for the cultivation of a bioartificial vascular graft, Engineering in Life Sciences.
Leibold, C., Walhalla, M., Blume, C., Blume, H., Wilhelmi, M. (2015): A real-time monitoring system controller for medical tissue engineering bioreactors,IEEE Xplore.
Wichert, N., Torres, L., Wahalla, M., Blume, C., Heisterkamp, A., Blume, H.: Laser-based light inductio of GFp synthesis in CHO-K1 cells as a model for optogenetics in human cells, Hearing 4 All Summer School, Soltau (2018)
Wichert, N., Hans, S., Wahalla, M., Reinard, T., Blume, C., Blume, H.: Optogentically induced protein expression in mammalian cells, Hearing 4 All Symposium, Oldenburg (2018)
Heene, S., Thoms, S., Jonczyk, R., Stanislawski, N., Blume, H., Blume,, C.: Development of microvascular structures inside 3D-printed scaffolds in comparison to fibrin coated scaffolds manufactured by porogen leaching, Würzburg (2018)
Heene; S., Thoms; S., Jonczyk; R., Scheper; T., Blume, C.: Development of microvascular structures inside porous fibrin coated polydioxanon and PLLA/PLGA scaffolds, 3D Cell Culture, Freiburg (2018)
Thoms, S., Oyono, V., Jonczyk, R., Scheper, T., Blume, C.: Tubular-like structure formation of HUVECs in a co-cultivation system with hMSCs, Global Biotechnology Congress, Boston (2017)
Leibold, C., Jonczyk, R., Heene, S., Blume, H., Blume, C.: A Bioreactor-System for Cultivation and Quality Control of 3D-printed Vascular Grafts, BioEngineering, Boston (2017)