Cultivo condral in vitro bajo estímulos de compresión y cizallamiento. De las células troncales mesenquimales al cartílago hialino / In vitro chondral culture under compression and shear stimuli. From mesenchymal stem cells to hyaline cartilage

INTRODUCCIÓN: La creación in vitro de cartílago hialino articular supone un reto, ya que, a día de hoy, no se ha conseguido la síntesis ex vivo de un tejido estructurado con las mismas propiedades biomecánicas e histológicas del cartílago articular. Para simular las condiciones fisiológicas hemos diseñado un sistema de cultivo in vitro que reproduce el movimiento articular. MATERIAL Y MÉTODO: Hemos desarrollado un biorreactor de cultivo celular que imprime un estímulo mecánico sobre una matriz de elastina en la que están embebidas células troncales mesenquimales (MSC). La primera fase de estudio corresponde al desarrollo de un biorreactor para cultivo de cartílago hialino y la comprobación de la viabilidad celular en la matriz de elastina en ausencia de estímulo. La segunda fase del estudio engloba el cultivo de MSC bajo estímulo mecánico y el análisis del tejido resultante. RESULTADOS: Tras el cultivo bajo estímulo mecánico no obtuvimos tejido hialino por falta de celularidad y desestructuración de la matriz. CONCLUSIÓN: El patrón de estímulo utilizado no ha resultado efectivo para la generación de cartílago hialino, por lo que se deberán explorar otras combinaciones en futuras investigaciones

INTRODUCTION: The in vitro creation of hyaline joint cartilage is a challenge since, to date, the ex vivo synthesis of a structured tissue with the same biomechanical and histological properties of the joint cartilage has not been achieved. To simulate the physiological conditions we have designed an in vitro culture system that reproduces joint movement. MATERIAL AND METHOD: We have developed a cell culture bioreactor that prints a mechanical stimulus on an elastin matrix, in which mesenchymal stem cells (MSC) are embedded. The first phase of study corresponds to the development of a bioreactor for hyaline cartilage culture and the verification of cell viability in the elastin matrix in the absence of stimulus. The second phase of the study includes the MSC culture under mechanical stimulus and the analysis of the resulting tissue. RESULTS: After culture under mechanical stimulation we did not obtain hyaline tissue due to lack of cellularity and matrix destructuring. CONCLUSION: The stimulus pattern used has not been effective in generating hyaline cartilage, so other combinations should be explored in future research

In vitro chondral culture under compression and shear stimuli. From mesenchymal stem cells to hyaline cartilage. / Cultivo condral in vitro bajo estímulos de compresión y cizallamiento. De las células troncales mesenquimales al cartílago hialino.

INTRODUCTION: The in vitro creation of hyaline joint cartilage is a challenge since, to date, the ex vivo synthesis of a structured tissue with the same biomechanical and histological properties of the joint cartilage has not been achieved. To simulate the physiological conditions we have designed an in vitro culture system that reproduces joint movement. MATERIAL AND METHOD: We have developed a cell culture bioreactor that prints a mechanical stimulus on an elastin matrix, in which mesenchymal stem cells (MSC) are embedded. The first phase of study corresponds to the development of a bioreactor for hyaline cartilage culture and the verification of cell viability in the elastin matrix in the absence of stimulus. The second phase of the study includes the MSC culture under mechanical stimulus and the analysis of the resulting tissue. RESULTS: After culture under mechanical stimulation we did not obtain hyaline tissue due to lack of cellularity and matrix destructuring. CONCLUSION: The stimulus pattern used has not been effective in generating hyaline cartilage, so other combinations should be explored in future research.

Use of proteolytic sequences with different cleavage kinetics as a way to generate hydrogels with preprogrammed cell-infiltration patterns imparted over their given 3D spatial structure.

Control over biodegradation processes is crucial to generate advanced functional structures with a more interactive and efficient role for biomedical applications. Herein, a simple, high-throughput approach is developed based on a three-dimensional (3D)-structured system that allows a preprogramed spatial-temporal control over cell infiltration and biodegradation. The 3D-structured system is based on elastin-like recombinamers (ELRs) characterized by differences in the kinetics of their peptide cleavage and consists of a three-layer hydrogel disk comprising an internal layer containing a rapidly degrading component, with the external layers containing a slow-degrading ELR. This structure is intended to invert the conventional pattern of cell infiltration, which goes from the outside to the inside of the implant, to allow an anti-natural process in which infiltration takes place first in the internal layer and later progresses to the outer layers. Time-course in vivo studies proved this hypothesis, i.e. that it is possible to drive the infiltration of cells over time in a given 3D-structured implant in a controlled and predesigned way that is able to overcome the natural tendency of conventional cell infiltration. The results obtained herein open up the possibility of applying this concept to more complex systems with multiple biological functions.

Bioactive scaffolds based on elastin-like materials for wound healing.

Wound healing is a complex process that, in healthy tissues, starts immediately after the injury. Even though it is a natural well-orchestrated process, large trauma wounds, or injuries caused by acids or other chemicals, usually produce a non-elastic deformed tissue that not only have biological reduced properties but a clear aesthetic effect. One of the main drawbacks of the scaffolds used for wound dressing is the lack of elasticity, driving to non-elastic and contracted tissues. In the last decades, elastin based materials have gained in importance as biomaterials for tissue engineering applications due to their good cyto- and bio-compatibility, their ease handling and design, production and modification. Synthetic elastin or elastin like-peptides (ELPs) are the two main families of biomaterials that try to mimic the outstanding properties of natural elastin, elasticity amongst others; although there are no in vivo studies that clearly support that these two families of elastin based materials improve the elasticity of the artificial scaffolds and of the regenerated skin. Within the next pages a review of the different forms (coacervates, fibres, hydrogels and biofunctionalized surfaces) in which these two families of biomaterials can be processed to be applied in the wound healing field have been done. Here, we explore the mechanical and biological properties of these scaffolds as well as the different in vivo approaches in which these scaffolds have been used.