scholarly journals 3D Printable and Computational Models of the Bone Marrow Mechanical Environment

Author(s):  
Alexander Regner

Aged individuals and astronauts experience bone loss despite rigorous physical activity. Bone mechanoresponse is in part regulated by mesenchymal stem cells (MSCs). We reported that daily low intensity vibration (LIV) restores MSC proliferation in senescence and simulated microgravity models, suggesting reduced mechanical signal delivery to MSCs likely contributes to declining bone mechanoresponse. To this end, we have developed a 3D bone marrow analog which controls trabecular geometry, marrow mechanics and external stimuli. Finite element (FE) models of hydrogels, representing bone marrow, were generated using instantaneous compression (1000% strain/s, 20% strain) and relaxation experiments (100s) of both gelatin and hyaluronin-based hydrogels. Experimental and in silico vibration experiments using molded-gelatin wells (widths= 4 , 5, 6 and 8 mm) were performed under 1g acceleration, 100 Hz for FE model calibration. For MSC experiments, 0.25cmgyroid-based trabeculae of bone volume fractions (BV/TV) corresponding to adult (25%) and aged (13%) mice were printed using polylactic acid. MSCs encapsulated (1x106 cells/mL) in migration-permissive hydrogelswithin [sic] printed trabeculae were exposed to LIV (1g, 100 Hz, 1 hour/day). After 14 days, type-I collagen, Ki-67, f-actin (n=3/grp) were quantified for extracellular matrix composition, proliferation, and morphology and grouped with respect to the maximum von Mises strain for 13.5% and 25% BV/TV scaffolds using the calibrated FE models.

2009 ◽  
Vol 131 (10) ◽  
Author(s):  
Jinjin Ma ◽  
Kristen Goble ◽  
Michael Smietana ◽  
Tatiana Kostrominova ◽  
Lisa Larkin ◽  
...  

The incidence of ligament injury has recently been estimated at 400,000/year. The preferred treatment is reconstruction using an allograft, but outcomes are limited by donor availability, biomechanical incompatibility, and immune rejection. The creation of an engineered ligament in vitro solely from patient bone marrow stromal cells (has the potential to greatly enhance outcomes in knee reconstructions. Our laboratory has developed a scaffoldless method to engineer three-dimensional (3D) ligament and bone constructs from rat bone marrow stem cells in vitro. Coculture of these two engineered constructs results in a 3D bone-ligament-bone (BLB) construct with viable entheses, which was successfully used for medial collateral ligament (MCL) replacement in a rat model. 1 month and 2 month implantations were applied to the engineered BLBs. Implantation of 3D BLBs in a MCL replacement application demonstrated that our in vitro engineered tissues grew and remodeled quickly in vivo to an advanced phenotype and partially restored function of the knee. The explanted 3D BLB ligament region stained positively for type I collagen and elastin and was well vascularized after 1 and 2 months in vivo. Tangent moduli of the ligament portion of the 3D BLB 1 month explants increased by a factor of 2.4 over in vitro controls, to a value equivalent to those observed in 14-day-old neonatal rat MCLs. The 3D BLB 1 month explants also exhibited a functionally graded response that closely matched native MCL inhomogeneity, indicating the constructs functionally adapted in vivo.


2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Hongliang He ◽  
Xiaozhen Liu ◽  
Liang Peng ◽  
Zhiliang Gao ◽  
Yun Ye ◽  
...  

Interactions between stem cells and extracellular matrix (ECM) are requisite for inducing lineage-specific differentiation and maintaining biological functions of mesenchymal stem cells by providing a composite set of chemical and structural signals. Here we investigated if cell-deposited ECM mimickedin vivoliver's stem cell microenvironment and facilitated hepatogenic maturation. Decellularization process preserved the fibrillar microstructure and a mix of matrix proteins in cell-deposited ECM, such as type I collagen, type III collagen, fibronectin, and laminin that were identical to those found in native liver. Compared with the cells on tissue culture polystyrene (TCPS), bone marrow mesenchymal stem cells (BM-MSCs) cultured on cell-deposited ECM showed a spindle-like shape, a robust proliferative capacity, and a suppressed level of intracellular reactive oxygen species, accompanied with upregulation of two superoxide dismutases. Hepatocyte-like cells differentiated from BM-MSCs on ECM were determined with a more intensive staining of glycogen storage, an elevated level of urea biosynthesis, and higher expressions of hepatocyte-specific genes in contrast to those on TCPS. These results demonstrate that cell-deposited ECM can be an effective method to facilitate hepatic maturation of BM-MSCs and promote stem-cell-based liver regenerative medicine.


1997 ◽  
Vol 35 (6) ◽  
pp. 433-437 ◽  
Author(s):  
K. Kusumoto ◽  
K. Besshoi ◽  
K. Fujimura ◽  
Y. Ogawa ◽  
T. Iizuka
Keyword(s):  

2006 ◽  
Vol 50 (4) ◽  
pp. 542-551
Author(s):  
Hideaki Kato ◽  
Katsutoshi Wakabayashi ◽  
Huminori Iwasa ◽  
Tadaharu Kawawa ◽  
Tetsuhiko Tachikawa

Blood ◽  
1985 ◽  
Vol 66 (2) ◽  
pp. 447-455 ◽  
Author(s):  
D Zipori ◽  
J Toledo ◽  
K von der Mark

Abstract Study of a series of stromal cell lines from mouse bone marrow (MBA) verified and extended their classification as phenotypically distinct subtypes. Production of extracellular matrix proteins was examined using specific antibodies. Fibronectin and laminin were detected in all of the cell lines tested, yet 14F1.1 adipocytes exhibited particularly prominent extracellular deposition. This cell line and MBA-13.2 cells were positive to both collagen types I and IV, whereas MBA-1 and MBA- 2.1 were stained with anticollagen type I antibodies only. Coculture experiments revealed differences among the lines in their effects on normal myeloid cells and leukemic cell lines. In promoting the in vitro accumulation of myeloid progenitors (CFU-C), 14F1.1 cells surpassed the others. The MBA-2.1 cell line was particularly inhibitory to MPC-11 plasmacytoma and Friend erythroleukemia cells. However, the latter were refractory to other stromal cell lines, whereas MPC-11 cells were inhibited to various degrees by virtually all of the cell lines. Physical separation between the interacting cells reduced the inhibition in some but not all cases, and no inhibitory activity was detected in conditioned media. The MBA-13 stromal cells synergistically promoted the differentiation of dimethylsulfoxide (Me2SO)-induced Friend erythroleukemia. The latter cells themselves, at high concentrations, as well as some of the stromal cell lines and unrelated adherent cells, antagonized the Me2SO effect, revealing possible reversible stages in the Friend cell differentiation pathway.


2021 ◽  
Vol 11 (8) ◽  
pp. 1630-1635
Author(s):  
Bin Wu ◽  
Fenghua Bai ◽  
Jianping Lin ◽  
Guangji Wang ◽  
Wentao Cai ◽  
...  

Aging affects bone marrow mesenchymal stem cells (BMSC) differentiation. PTEN12 regulates cell proliferation and apoptosis. However, whether PTEN12 affects BMSCs osteogenic differentiation during aging is unknown. Two BMSCs derived from Zempster24−/− (senescence) and Zempster24+/+ (normal) mice were cultured in vitro. Real-time PCR analysis was used to analyze PTEN12 expression. PTEN12 siRNA was transfected into senescent Zempster24-/-BMSCs and after 14 days of osteogenic induction, cell proliferation was analyzed by MTT method along with measuring expression of osteocalcin, type I collagen, RUNX2 and OPN by Real time PCR, ALP activity, and TGFβ/smad signaling protein expression by Western blot. Compared to normal BMSCs, PTEN12 level in aging BMSCs was significantly elevated, osteocalcin, type I collagen, RUNX2 and OPN mRNA level was decreased along with reduced ALP activity and TGFβ1 and Smad2 expression (P < 0.05). PTEN12 siRNA transfection into senescent BMSCs significantly down-regulated PTEN12, upregulated osteocalcin, type I collagen, RUNX2 and OPN mRNA, increased ALP activity and TGFβ1 and Smad2 expression (P <0.05). Aging increases PTEN12 level and inhibits BMSCs osteogenic differentiation. Down-regulation of PTEN12 in BMSCs during aging can promote BMSCs osteogenic differentiation by regulating TGFβ/smad signaling pathway.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Masanobu Izumikawa ◽  
Keijiro Hayashi ◽  
Mohammad Ali Akbor Polan ◽  
Jia Tang ◽  
Takashi Saito

The aim of this study was to clarify the function of amelogenin, the major protein of enamel matrix derivative, on the proliferation, differentiation, and mineralization of cultured rat bone marrow stem cells (BMSCs), toward the establishment of future bone regenerative therapies. No differences in the morphology of BMSCs or in cell numbers were found between amelogenin addition and additive-free groups. The promotion of ALPase activity and the formation of mineralized nodules were detected at an early stage in amelogenin addition group. In quantitative real-time RT-PCR, mRNA expression of osteopontin, osteonectin, and type I collagen was promoted for 0.5 hours and 24 hours by addition of amelogenin. The mRNA expression of osteocalcin and DMP-1 was also stimulated for 24 hours and 0.5 hours, respectively, in amelogenin addition group. These findings clearly indicate that amelogenin promoted the differentiation and mineralization of rat BMSCs but did not affect cell proliferation or cell morphology.


2019 ◽  
Vol 8 (3) ◽  
pp. 329 ◽  
Author(s):  
Luca Dalle Carbonare ◽  
Monica Mottes ◽  
Anna Brunelli ◽  
Michela Deiana ◽  
Samuele Cheri ◽  
...  

Direct oral anti-coagulants (DOACs) are employed in clinical practice for the prevention and treatment of recurrent venous thromboembolism and for the prevention of stroke in non-valvular atrial fibrillation. DOACs directly and reversibly inhibit activated factor X or thrombin and can interfere with other pathophysiological processes such as inflammation, lipid metabolism, and bone turnover. We aimed to evaluate the possible effects of DOACs on osteogenesis and angiogenesis. We treated 34 patients affected by cardiovascular disorders with DOACs; biochemical and molecular analyses were performed before and after three months of treatment. Circulating progenitors (CPs; CD34−, CD45−, CD14−, CD73+, CD105+), which share typical bone marrow stem cell (MSCs) features, were harvested from peripheral blood of the study subjects to monitor the expression of osteogenesis-related genes RUNX2 and SPARC. Human umbilical vein endothelial cells (HUVECs) were used to probe angiogenesis-related VEGF, CD31, and CD105 gene expression. We performed co-culture experiments using a commercial human mesenchymal stem cells line (hMSCs) obtained from bone marrow and HUVECs. Clinical parameters related to bone metabolism, coagulation, renal and liver function, and the lipid profile were evaluated. Values of the C-terminal telopeptide type I collagen (CTX) increased after the treatment. We found a significant increase in osteogenesis marker gene expression in CPs after three months of anticoagulant therapy. An increase in the RUNX2 expression determinant alone was detected instead in hMSCs co-cultured with HUVECs in the presence of treated patients’ sera. The VEGF, CD31, and CD105 marker genes appeared to be significantly upregulated in HUVECs co-cultured with hMSCs in the presence of treated patients’ sera. Under these conditions, new vessel formation increased as well. Our results highlight an unexpected influence of DOAC therapy on osteogenic commitment and vascular endothelial function promotion.


Blood ◽  
2012 ◽  
Vol 119 (21) ◽  
pp. 5048-5056 ◽  
Author(s):  
Benoit Detry ◽  
Charlotte Erpicum ◽  
Jenny Paupert ◽  
Silvia Blacher ◽  
Catherine Maillard ◽  
...  

Abstract Lymphatic dysfunctions are associated with several human diseases, including lymphedema and metastatic spread of cancer. Although it is well recognized that lymphatic capillaries attach directly to interstitial matrix mainly composed of fibrillar type I collagen, the interactions occurring between lymphatics and their surrounding matrix have been overlooked. In this study, we demonstrate how matrix metalloproteinase (MMP)–2 drives lymphatic morphogenesis through Mmp2-gene ablation in mice, mmp2 knockdown in zebrafish and in 3D-culture systems, and through MMP2 inhibition. In all models used in vivo (3 murine models and thoracic duct development in zebrafish) and in vitro (lymphatic ring and spheroid assays), MMP2 blockage or down-regulation leads to reduced lymphangiogenesis or altered vessel branching. Our data show that lymphatic endothelial cell (LEC) migration through collagen fibers is affected by physical matrix constraints (matrix composition, density, and cross-linking). Transmission electron microscopy and confocal reflection microscopy using DQ-collagen highlight the contribution of MMP2 to mesenchymal-like migration of LECs associated with collagen fiber remodeling. Our findings provide new mechanistic insight into how LECs negotiate an interstitial type I collagen barrier and reveal an unexpected MMP2-driven collagenolytic pathway for lymphatic vessel formation and morphogenesis.


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