Fabian Langenbach

Publications

• Impact of DAG stimulation on mineral synthesis, mineral structure and osteogenic differentiation of human cord blood stem cells.

  Lydia Lammers, Christian Naujoks, Karin Berr, Rita Depprich, Norbert Kübler, Ulrich Meyer, Fabian Langenbach, Beate Lüttenberg, Gesine Kögler, Hans-Peter Wiesmann, Jörg Handschel

  Stem cell research. 03/2012; 8(2):193-205.

  It remains unexplored in what way osteogenic stimulation with dexamethasone, ascorbic acid and β-glycerol phosphate (DAG) influences the process of mineralization, the composition and structure of the assembled mineral. Therefore, we analyzed and characterized biomineralization in DAG-stimulated and... [more] It remains unexplored in what way osteogenic stimulation with dexamethasone, ascorbic acid and β-glycerol phosphate (DAG) influences the process of mineralization, the composition and structure of the assembled mineral. Therefore, we analyzed and characterized biomineralization in DAG-stimulated and unstimulated 3D human unrestricted somatic stem cell (USSC) cultures. Microspheres were analyzed by histological staining, scanning electron microscopy (SEM), semi-quantitative energy-dispersive X-ray spectroscopy (EDX), quantitative wavelength-dispersive X-ray spectroscopy (WDX), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and Raman spectroscopy. Mineral material was detected by SEM and histological staining in both groups, and showed structural differences. DAG influenced the differentiation of USSCs and the formation, structure and composition of the assembled mineral. SEM showed that cells of the +DAG spheres exhibited morphological signs of osteoblast-like cells. EDX and WDX confirmed a Ca-P mineral in both groups. Overall, the mineral material found showed structural similarities to the mineral substance of bony material.
• 1.91

  Impact points

  Improvement of the cell-loading efficiency of biomaterials by inoculation with stem cell-based microspheres, in osteogenesis.

  Fabian Langenbach, Christian Naujoks, Andrea Laser, Michael Kelz, Pia Kersten-Thiele, Karin Berr, Rita Depprich, Norbert Kübler, Gesine Kögler, Jörg Handschel

  Journal of biomaterials applications. 01/2012; 26(5):549-64.

  In critical-size bone defects, autologous or allogenic cells are required in addition to compatible biomaterials for the successful defect healing. State of the art inoculation methods of biomaterials are based on the application of cell suspensions to the biomaterial. However, only less amounts of ... [more] In critical-size bone defects, autologous or allogenic cells are required in addition to compatible biomaterials for the successful defect healing. State of the art inoculation methods of biomaterials are based on the application of cell suspensions to the biomaterial. However, only less amounts of cells can be applied and sufficient adhesion to the material is required. Therefore, it was investigated whether the advantages of stem cell-based microspheres and insoluble collagenous bone matrix (ICBM) scaffolds can be combined which can lead to an advancement in cell seeding on biomaterials. Microspheres were produced from unrestricted somatic stem cells from human umbilical cord blood and were mounted on ICBM scaffolds. Following the incubation with osteogenic or control medium, the constructs were analyzed histologically after 3, 7, 14, and 28 days. Alizarin Red S and von Kossa staining revealed microsphere mineralization after 3 days in osteogenic and after 14 days in control medium. Meanwhile, a time-dependent increase in tissue, growing out of the microspheres, was detected. Our results provide evidence that microsphere-ICBM constructs are promising candidates for approaches of bone regeneration. They allow the transfer of substantially high numbers of cells in partially mineralized constructs.

• Generation and differentiation of microtissues from multipotent precursor cells for use in tissue engineering.

  Fabian Langenbach, Karin Berr, Christian Naujoks, Andrea Hassel, Michael Hentschel, Rita Depprich, Norbert R Kubler, Ulrich Meyer, Hans-Peter Wiesmann, Gesine Kögler, Jörg Handschel

  Nature protocols. 11/2011; 6(11):1726-35.

  This protocol describes an effective method for the production of spherical microtissues (microspheres), which can be used for a variety of tissue-engineering purposes. The obtained microtissues are well suited for the study of osteogenesis in vitro when multipotent stem cells are used. The dimensio... [more] This protocol describes an effective method for the production of spherical microtissues (microspheres), which can be used for a variety of tissue-engineering purposes. The obtained microtissues are well suited for the study of osteogenesis in vitro when multipotent stem cells are used. The dimensions of the microspheres can easily be adjusted according to the cell numbers applied in an individual experiment. Thus, microspheres allow for the precise administration of defined cell numbers at well-defined sites. Here we describe a detailed workflow for the production of microspheres using unrestricted somatic stem cells from human umbilical cord blood and adapted protocols for the use of these microspheres in histological analysis. RNA extraction methods for mineralized microtissues are specifically modified for optimum yields. The duration of running the complete protocol without preparatory cell culture but including 2 weeks of microsphere incubation, histological staining and RNA isolation is about 3 weeks.
• 1.91

  Impact points

  Biocompatibility of osteogenic predifferentiated human cord blood stem cells with biomaterials and the influence of the biomaterial on the process of differentiation.

  Christian Naujoks, Fabian Langenbach, Karin Berr, Rita Depprich, Norbert Kübler, Ulrich Meyer, Jörg Handschel, Gesine Kögler

  Journal of biomaterials applications. 03/2010; 25(5):497-512.

  Modern cell-based bone reconstruction therapies offer new therapeutic opportunities and tissue engineering represents a more biological-oriented approach to heal bone defects of the skeleton. Human unrestricted somatic stem cells (USSCs) derived form umbilical cord blood offer new promising aspects ... [more] Modern cell-based bone reconstruction therapies offer new therapeutic opportunities and tissue engineering represents a more biological-oriented approach to heal bone defects of the skeleton. Human unrestricted somatic stem cells (USSCs) derived form umbilical cord blood offer new promising aspects e.g., can differentiate into osteogenetic cells. Furthermore these cells have fewer ethical and legal restrictions compared to embryonic stem cells (ESCs). The purpose of this study was to evaluate the compatibility of osteogenic pre-differentiated USSCs with various biomaterials and to address the question, whether biomaterials influence the process of differentiation of the USSCs. After osteogenic differentiation with DAG USSCs were cultivated with various biomaterials. To asses the biocompatibility of USSCs the attachment and the proliferation of the cells on the biomaterial were measured by a CyQUANT(®) assay, the morphology was analyzed by scanning electron microscopy and the influence of the gene expression was analyzed by real time PCR. Our results provide evidence that insoluble collagenous bone matrix followed by β-tricalciumphosphate is highly suitable for bone tissue engineering regarding cell attachment and proliferation. The gene expression analysis indicates that biomaterials influence the gene expression of USSCs. These results are in concordance with our previous study with ESCs.

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• 4.64

  Impact points

  Comparison of ectopic bone formation of embryonic stem cells and cord blood stem cells in vivo.

  Jörg Handschel, Christian Naujoks, Fabian Langenbach, Karin Berr, Rita A Depprich, Michelle A Ommerborn, Norbert R Kübler, Matthias Brinkmann, Gesine Kögler, Ulrich Meyer

  Tissue engineering. Part A. 03/2010; 16(8):2475-83.

  Cell-based reconstruction therapies promise new therapeutic opportunities for bone regeneration. Unrestricted somatic stem cells (USSC) from cord blood and embryonic stem cells (ESCs) can be differentiated into osteogenic cells. The purpose of this in vivo study was to compare their ability to induc... [more] Cell-based reconstruction therapies promise new therapeutic opportunities for bone regeneration. Unrestricted somatic stem cells (USSC) from cord blood and embryonic stem cells (ESCs) can be differentiated into osteogenic cells. The purpose of this in vivo study was to compare their ability to induce ectopic bone formation in vivo. Human USSCs and murine ESCs were cultured as both monolayer cultures and micromasses and seeded on insoluble collagenous bone matrix (ICBM). One week and 1, 2, and 3 months after implanting the constructs in immune-deficient rats, computed tomography scans were performed to detect any calcification. Subsequently, the implanted constructs were examined histologically. The radiological examination showed a steep increase in the mineralized bone-like tissue in the USSC groups. This increase can be considered as statistically significant compared to the basic value. Moreover, the volume and the calcium portion measured by computed tomography scans were about 10 times higher than in the ESC group. The volume of mineralization in the ESC group increased to a much smaller extent over the course of time, and the control group (ICBM without cells) showed almost no alterations during the study. The histological examinations parallel the radiological findings. Cord blood stem cells in combination with ICBM-induced ectopic bone formation in vivo are stronger than ESCs.
• 4.64

  Impact points

  Osteogenic differentiation influence stem cell migration out of scaffold free microspheres.

  Fabian Langenbach, Christian Naujoks, Pia Valeska Kersten-Thiele, Karin Berr, Rita Depprich, Norbert Kübler, Gesine Kögler, Jörg Handschel

  Tissue engineering. Part A. 09/2009;

  Complete bone regeneration of critical size defects (CSDs) frequently fail due to the use of acellular bone substitutes and due to partially negative influences of artificial scaffolds. However, the supply of cells to CSDs is essential for the regeneration. Therefore, engineered scaffold free tissue... [more] Complete bone regeneration of critical size defects (CSDs) frequently fail due to the use of acellular bone substitutes and due to partially negative influences of artificial scaffolds. However, the supply of cells to CSDs is essential for the regeneration. Therefore, engineered scaffold free tissues, with outgrowing cells that fill up spaces in the bony defect, are promising candidates for bone regeneration approaches. Here we demonstrate such a scaffold free tissue construct (microspheres) that, if osteogenic differentiated, mineralizes while maintaining the capability to let cells grow out of the united cell structure. A superior outgrowth capability of microspheres composed of human cord-blood derived USSCs (unrestricted somatic stem cells) compared to murine ESCs (embryonic stem cells) was found and a time dependent reduction in outgrowth was evident, in vitro. Even after five days of osteoinduction and strong mineralization cells migrate out of the microsphere. Since migration of cells out of USSC-microspheres was also found in extracellular matrix gel, we suggest that cells would migrate also in vivo. Thus microspheres could serve as the scaffold and the source of osteogenic cells in future bone regeneration approaches. Furthermore microspheres permit the precise administration of large amount of cells into an area of interest.