Formation of bone extracellular matrix in a rotational bioreactor: Preseeding of human mesenchymal stromal cells on a thin polymer scaffold

2021 ◽  
pp. 1-17
Author(s):  
Peter Mikhailovich Larionov ◽  
Nikolai Anatolevitch Maslov ◽  
Vladimir Leonidovitch Ganymedov ◽  
Valeriy Pavlovitch Tereshchenko ◽  
Alexander Gennadevitch Samokhin ◽  
...  

BACKGROUND: Periprosthetic osteolysis is known to be the main reason for aseptic instability after the arthroplasty or dental implantation. The use of tissue-engineered scaffolds that allow bone formation area, produced using flow or rotational bioreactor, seems to be a promising approach for such bone lesions treatment. OBJECTIVE: To evaluate the bone neo-extracellular matrix formation within the three-week culture of a scaffold in a coaxial rotational bioreactor generating the preliminary mathematically modelled FSS values with the aim to develop a tissue-engineered scaffold for periprosthetic osteolysis prevention, but reactor critical characteristics like fluid shear stress (FSS) should be fine-tuned to achieve good cell density and prevent cell loss by the scaffold. METHODS: Thin film biodegradable polymer carrier, produced with electrospun and then seeded with hMSCs (human mesenchymal stromal cell) and culture for three weeks in rotational bioreactor, which generates the preliminary math model-calculated FSS from 4 to 8 mPa. Results were assessed with laser scanning confocal microscopy with immunofluorescence, and electron scanning microscopy with spectroscopy. RESULTS: After two weeks of culture, there were no significant differences between the density of hMSC cultured in the static conditions and bioreactor but after 3 weeks the cell density in the bioreactor increased by 35% compared to the static conditions (up to 3.53×106±462 per 1 cm2, P < 0.001). The immunofluorescence intensity exhibited by type I collagen after two and three weeks of culture increased 2.5-fold (48.3±0.39 a.u., P < 0.001) and 1.31-fold (74.0±0.29 a.u., P < 0.001) in the bioreactor, but for osteopontin after 3 weeks of culture in the static conditions was similar to those in the bioreactor. CONCLUSIONS: Optimization of the reactor characteristics with the mathematically modelled FSS values could significantly improve cell proliferation, differentiation, and enhanced formation of the neo-extracellular matrix within 3 weeks in the rotational bioreactor.

Cells ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1046
Author(s):  
Jorge Martinez ◽  
Patricio C. Smith

Desmoplastic tumors correspond to a unique tissue structure characterized by the abnormal deposition of extracellular matrix. Breast tumors are a typical example of this type of lesion, a property that allows its palpation and early detection. Fibrillar type I collagen is a major component of tumor desmoplasia and its accumulation is causally linked to tumor cell survival and metastasis. For many years, the desmoplastic phenomenon was considered to be a reaction and response of the host tissue against tumor cells and, accordingly, designated as “desmoplastic reaction”. This notion has been challenged in the last decades when desmoplastic tissue was detected in breast tissue in the absence of tumor. This finding suggests that desmoplasia is a preexisting condition that stimulates the development of a malignant phenotype. With this perspective, in the present review, we analyze the role of extracellular matrix remodeling in the development of the desmoplastic response. Importantly, during the discussion, we also analyze the impact of obesity and cell metabolism as critical drivers of tissue remodeling during the development of desmoplasia. New knowledge derived from the dynamic remodeling of the extracellular matrix may lead to novel targets of interest for early diagnosis or therapy in the context of breast tumors.


Biochemistry ◽  
1991 ◽  
Vol 30 (29) ◽  
pp. 7097-7104 ◽  
Author(s):  
Kou Katayama ◽  
Jerome M. Seyer ◽  
Rajendra Raghow ◽  
Andrew H. Kang

1995 ◽  
Vol 269 (1) ◽  
pp. L52-L58 ◽  
Author(s):  
C. A. Partridge

Incubation of bovine pulmonary microvascular endothelial (BPMVE) cells in low O2 content (95% N2-5% CO2) for 4 h increased monolayer permeability to dextran almost twofold and also increased the incidence of intercellular gaps and intracellular actin stress fibers. Hypoxic incubation decreased the extracellular matrix contents of fibronectin and vitronectin, proteins that serve as anchorage points for the endothelial cells. This state was reversed after 24 h of hypoxic incubation, and the BPMVE monolayer permeability to dextran was less than that of normoxic controls. The monolayer had fewer intercellular gaps and stress fibers, and the extracellular matrix contained increased amounts of fibronectin, vitronectin, and type I collagen. These alterations stimulated by 24 h of hypoxic incubation were resolved within 4 h of reoxygenation in room air supplemented with 5% CO2. These studies indicate that incubation of endothelial monolayers in hypoxic conditions first increases and then decreases monolayer permeability, through increased and decreased formation of intercellular gaps.


2019 ◽  
Vol 4 (4) ◽  
pp. 2473011419S0038
Author(s):  
Nicolas Shealy ◽  
James Rex ◽  
Amy Bradshaw ◽  
Christopher Gross

Category: Basic Sciences/Biologics Introduction/Purpose: New approaches to improve tendon repair after injury are an active area of research. Critical properties of tendons are governed by the production and assembly of fibrillar collagens. Cross-linking of fibrillar collagen is a primary factor in determining the function and mechanical properties of the collagen fibers comprising Enzymatic cross-linking by lysyl oxidase in the telopeptide domain of collagen I and III is one determinant of collagen fibril assembly and is the best characterized biochemical cross-link. Transglutaminase catalyzes the modification of lysine residues that in turn form an n-e-glutamyl lysine bond between proteins in the extracellular space. We hypothesize that transglutaminase-dependent modification of collagen in tendons is also a principal determinant of tendon strength and function and is dependent upon tension. Methods: 3-D collagen gels were generated from acid solubilized type I collagen with telopeptides (Advanced BioMatrix). Collagen gels were plated and loaded into a MechanoCulture FX apparatus (CellScale). Gels were subjected to a 10% stretch for 24 hrs at 37°C at 2hz (dynamic) or no stretch, static controls. Gels exposed to enzymatic cross-linking were incubated with either 2.4 ng of recombinant Transglutaminase 2 (Axxora) in a 10 mM Ca2+ solution. Inhibition and labeling of transglutaminase substrates was performed by incubation of collagen gels with 0.2 mM aminopentyl biotinamide in DMSO. Soluble collagen was separated from insoluble collagen by centrifugation at 10,000G. Insoluble fractions were boiled in SDS-Laemmli buffer prior to separation by SDS-PAGE. Collagen in soluble and insoluble fractions was evaluated by Coomassie stain whereas transglutaminase modification was detected via western blot using streptavidin conjugated horse radish peroxidase to detect biotinylated proteins. Results: Evaluation of collagen gels subjected to dynamic versus static stretch revealed minor differences in insoluble collagen incorporation in the two conditions. Notably, higher molecular weight cross-linked forms of collagen appeared to be higher in dynamic versus static gels. In the presence of transglutaminase, differences in higher molecular weight cross-linked forms of collagen, beta-bands, were also detected. Finally, incorporation of biotinylated transglutaminase substrate into collagen alpha bands was enriched in dynamic versus static cultures. Hence, preliminary results support a differential role for transglutaminase modification in collagen under cyclic tension versus static conditions. Conclusion: A better understanding of the role of dynamic stretching and differential tension in the regulation of collagen cross- link formation is predicted to contribute to improved strategies to treat injured tendons.


2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Yasmin ElTahir ◽  
Amna Al-Araimi ◽  
Remya R. Nair ◽  
Kaija J. Autio ◽  
Hongmin Tu ◽  
...  

Abstract Background Brucella is a facultative intracellular pathogen responsible for zoonotic disease brucellosis. Little is known about the molecular basis of Brucella adherence to host cells. In the present study, the possible role of Bp26 protein as an adhesin was explored. The ability of Brucella protein Bp26 to bind to extracellular matrix (ECM) proteins was determined by enzyme-linked immunosorbent assay (ELISA) and biolayer interferometry (BLI). Results ELISA experiments showed that Bp26 bound in a dose-dependent manner to both immobilized type I collagen and vitronectin. Bp26 bound weakly to soluble fibronectin but did not bind to immobilized fibronectin. No binding to laminin was detected. Biolayer interferometry showed high binding affinity of Bp26 to immobilized type I collagen and no binding to fibronectin or laminin. Mapping of Bp26 antigenic epitopes by biotinylated overlapping peptides spanning the entire sequence of Bp26 using anti Bp26 mouse serum led to the identification of five linear epitopes. Collagen and vitronectin bound to peptides from several regions of Bp26, with many of the binding sites for the ligands overlapping. The strongest binding for anti-Bp26 mouse serum, collagen and vitronectin was to the peptides at the C-terminus of Bp26. Fibronectin did not bind to any of the peptides, although it bound to the whole Bp26 protein. Conclusions Our results highlight the possible role of Bp26 protein in the adhesion process of Brucella to host cells through ECM components. This study revealed that Bp26 binds to both immobilized and soluble type I collagen and vitronectin. It also binds to soluble but not immobilized fibronectin. However, Bp26 does not bind to laminin. These are novel findings that offer insight into understanding the interplay between Brucella and host target cells, which may aid in future identification of a new target for diagnosis and/or vaccine development and prevention of brucellosis.


1993 ◽  
Vol 293 (2) ◽  
pp. 387-394 ◽  
Author(s):  
S R Lamandé ◽  
J F Bateman

A type I collagen reporter gene construct, designed to facilitate detailed analysis of the consequences of introduced structural and regulatory mutations on collagen biosynthesis and participation in the extracellular matrix, was produced by site-directed mutagenesis of the mouse COL1A1 gene. The reporter construct, pWTCI-Ile822, carried a single base change which converted the codon for amino acid 822 of the triple helix from methionine to isoleucine. This change allowed the reporter protein, [Ile822]alpha 1(I), to be distinguished from the wild-type alpha 1(I), and quantified, by its altered CNBr cleavage pattern. In mouse Mov13 cells, which synthesize no endogenous pro alpha 1(I), reporter chains associated with endogenous pro alpha 2(I), formed pepsin-stable triple helices and were secreted efficiently from the cell. The thermal stability of wild-type molecules and molecules containing the reporter [Ile822]alpha 1(I) chains was identical. The biosynthetic characteristics of wild-type and reporter chains were directly compared in stably transfected 3T6 cells. These cells did not make a distinction between reporter and endogenous alpha 1(I) chains, which were secreted from the cells at the same rate and were processed and deposited into the 3T6 cell in vitro accumulated extracellular matrix with equal efficiency. These data demonstrate that the helical sequence alteration in the reporter protein is functionally neutral and that the reporter construct, pWTCI-Ile822, is a suitable vector for the analysis of the biochemical effects of site-directed mutations in the putative COL1A1 functional domains.


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