A. Olivos Meza (Mexico City, MX)
National Institute of Rehabilitation Orthopedic Sports Medicine and ArthroscopyPresenter Of 3 Presentations
P064 - Allogeneic Chondrocyte Transplantation with Demineralized Bone Matrix Scaffolds to Repair Cartilage Lesions: A Rabbit Study
Abstract
Purpose
To regenerate hyaline cartilage like tissue using demineralized bone matrix scaffolds with allogenic chondrocytes in a rabbit model.
Methods and Materials
Allogenic chondrocytes were isolated and cultured from a donor rabbit. Chondrocytes were first mixed with chitosan (1: 1 proportion), this to promote cell adhesion when the chondrocytes were seeded in the DBM (5x5mm), at a density of 2x106 cells, the implants were kept in culture for two days to achieve cohesion. The cellular-scaffold was implanted in a grade-4 chondral lesion in the trochlear groove of the rabbit’s knee. At 12 weeks the rabbits were euthanized, by RT-PCR and immunofluorescence analysis looking for the expression of the SOX9, COL2A1 and aggrecan genes and histological stains. Subsequently, the samples were analyzed histologically with the modified O'Driscoll scale.
Results
Neocartilage was formed in both the cellular-scaffold and control empty group. However, the structural integrity, integration and bone regeneration in the repair tissue appeared to be much better in cell-scaffold group (Fig. 1) compared to the control group. Histologically, the formation of hyaline cartilage is carried out in the chondral lesions where the scaffold was implanted, which is confirmed by the O'Driscoll scale (Fig. 2). Similarly, positivity is produced by means of immunofluorescence for markers such as Collagen type 2, Agrecan and Sox-9, as well as the gene expression of SOX-9, COL2A1 and ACAN through PCR.
Conclusion
The DBM scaffold is a viable option, with sufficient chondrogenic potential for the formation of hyaline cartilage, which can make chondrocyte implantation a technique accessible to the population of developing countries.
P106 - 3D Printed Meniscal Model for Meniscal Substitution: Study in Rabbits
Abstract
Purpose
To create a three-dimensional meniscus model by robotic impression with PCL enriched with either mesenchymal stem cells or fibrochondrocytes for implantation in rabbits.
Methods and Materials
Fibrochondrocytes (FC) and Mesenchymal Stem Cells (MSC) were harvested from remnants of meniscus and bone marrow of rabbits. Those cells were expanded for 14 days in monolayer, then were seeded on 3D printed meniscus models of polycaprolactone polymer and cultured during 4 days. The meniscus model was generated from Magnetic Resonance Imaging (MRI) data from human meniscus using a scale reduction according with the average of different measurements performed to lateral meniscus of 6 months age rabbits. Meniscal cell-scaffolds were used for partial substitution of lateral meniscus in 6 rabbits. Implants were leave during 12 weeks and new-formed tissue was harvested for histology, inmmunofluorescence, and RNA isolation studies.
Results
Meniscal models showed calcein staining of either fibrochondrocytes and mesenchymal stem cells (Fig. 1). In the gross and histological analyses fibrocartilage like tissue was formed in both the FC and MSC groups but with better results in models seeded with fibrochondrocytes (Fig. 2). The presence of Col-1, Agrecane, and Col-2 has better expression in FC scaffolds compared to MSC group that showed osseous tissue formation. A third control acellular group also formed bone tissue as well as expressed RunX2 in RNA.
Conclusion
Is possible to form meniscus like tissue after 12-weeks of lateral 3D-printed meniscal substitution of PCL enriched with fibrochondrocytes
P122 - Clinical and T2-mapping Results of Meniscal Substitution with Cellularized Polyurethane Implants: 5-year Follow-up
Abstract
Purpose
To evaluate the clinical results and chondroprotective effect of polyurethane meniscal substitution enhanced with mobilized mesenchymal stem cells versus acellular implants at 48-monthsTo evaluate the clinical results and chondroprotective effect of polyurethane meniscal substitution enhanced with mobilized mesenchymal stem cells versus acellular implants at 48-months
Methods and Materials
Seventeen patients between 18-50 years old with past meniscectomies were enrolled in 2 groups, first, acellular polyurethane scaffold or second one polyurethane scaffold enriched with mesenchymal stem cell. Patients in the cellular group received filgrastim to stimulate mesenchymal stem cells that were harvested and cultured in the polyurethane scaffold during 2 weeks. Then scaffolds were implanted arthroscopically into partial meniscus defects. Concomitant injuries were treated during the same procedure. Changes in the surface of articular cartilage adjacent to the meniscal substitution were evaluated by T2 mapping 60 months with clinical scores as well.
Results
In tibial and femur T2 mapping ROI values for the cellular group were decreased in compared with acellular group at 24 months (P > 0.05) this difference tended to be lower in both groups after 24 months with not significant difference. In the clinical scores, Tegner & KOOS-QOL increased significantly at 12m while Lysholm got better at 18 m (p > 0.05) in the cellular group (Tab.1). The rest of the scales didn`t show significant difference between groups (p > 0.05). Second look at 12-months showed complete integration without rupture or loss of the implant in any group (Fig. 1)
Conclusion
Polyurethane meniscal scaffolds enhanced with mobilized mesenchymal stem cells shows benefit only the first 24 months, after this time this group does not show any advantage either in the protection of articular cartilage or in clinical scores over acellular scaffolds.
Presenter Of 3 Presentations
P064 - Allogeneic Chondrocyte Transplantation with Demineralized Bone Matrix Scaffolds to Repair Cartilage Lesions: A Rabbit Study
Abstract
Purpose
To regenerate hyaline cartilage like tissue using demineralized bone matrix scaffolds with allogenic chondrocytes in a rabbit model.
Methods and Materials
Allogenic chondrocytes were isolated and cultured from a donor rabbit. Chondrocytes were first mixed with chitosan (1: 1 proportion), this to promote cell adhesion when the chondrocytes were seeded in the DBM (5x5mm), at a density of 2x106 cells, the implants were kept in culture for two days to achieve cohesion. The cellular-scaffold was implanted in a grade-4 chondral lesion in the trochlear groove of the rabbit’s knee. At 12 weeks the rabbits were euthanized, by RT-PCR and immunofluorescence analysis looking for the expression of the SOX9, COL2A1 and aggrecan genes and histological stains. Subsequently, the samples were analyzed histologically with the modified O'Driscoll scale.
Results
Neocartilage was formed in both the cellular-scaffold and control empty group. However, the structural integrity, integration and bone regeneration in the repair tissue appeared to be much better in cell-scaffold group (Fig. 1) compared to the control group. Histologically, the formation of hyaline cartilage is carried out in the chondral lesions where the scaffold was implanted, which is confirmed by the O'Driscoll scale (Fig. 2). Similarly, positivity is produced by means of immunofluorescence for markers such as Collagen type 2, Agrecan and Sox-9, as well as the gene expression of SOX-9, COL2A1 and ACAN through PCR.
Conclusion
The DBM scaffold is a viable option, with sufficient chondrogenic potential for the formation of hyaline cartilage, which can make chondrocyte implantation a technique accessible to the population of developing countries.
P106 - 3D Printed Meniscal Model for Meniscal Substitution: Study in Rabbits
Abstract
Purpose
To create a three-dimensional meniscus model by robotic impression with PCL enriched with either mesenchymal stem cells or fibrochondrocytes for implantation in rabbits.
Methods and Materials
Fibrochondrocytes (FC) and Mesenchymal Stem Cells (MSC) were harvested from remnants of meniscus and bone marrow of rabbits. Those cells were expanded for 14 days in monolayer, then were seeded on 3D printed meniscus models of polycaprolactone polymer and cultured during 4 days. The meniscus model was generated from Magnetic Resonance Imaging (MRI) data from human meniscus using a scale reduction according with the average of different measurements performed to lateral meniscus of 6 months age rabbits. Meniscal cell-scaffolds were used for partial substitution of lateral meniscus in 6 rabbits. Implants were leave during 12 weeks and new-formed tissue was harvested for histology, inmmunofluorescence, and RNA isolation studies.
Results
Meniscal models showed calcein staining of either fibrochondrocytes and mesenchymal stem cells (Fig. 1). In the gross and histological analyses fibrocartilage like tissue was formed in both the FC and MSC groups but with better results in models seeded with fibrochondrocytes (Fig. 2). The presence of Col-1, Agrecane, and Col-2 has better expression in FC scaffolds compared to MSC group that showed osseous tissue formation. A third control acellular group also formed bone tissue as well as expressed RunX2 in RNA.
Conclusion
Is possible to form meniscus like tissue after 12-weeks of lateral 3D-printed meniscal substitution of PCL enriched with fibrochondrocytes
P122 - Clinical and T2-mapping Results of Meniscal Substitution with Cellularized Polyurethane Implants: 5-year Follow-up
Abstract
Purpose
To evaluate the clinical results and chondroprotective effect of polyurethane meniscal substitution enhanced with mobilized mesenchymal stem cells versus acellular implants at 48-monthsTo evaluate the clinical results and chondroprotective effect of polyurethane meniscal substitution enhanced with mobilized mesenchymal stem cells versus acellular implants at 48-months
Methods and Materials
Seventeen patients between 18-50 years old with past meniscectomies were enrolled in 2 groups, first, acellular polyurethane scaffold or second one polyurethane scaffold enriched with mesenchymal stem cell. Patients in the cellular group received filgrastim to stimulate mesenchymal stem cells that were harvested and cultured in the polyurethane scaffold during 2 weeks. Then scaffolds were implanted arthroscopically into partial meniscus defects. Concomitant injuries were treated during the same procedure. Changes in the surface of articular cartilage adjacent to the meniscal substitution were evaluated by T2 mapping 60 months with clinical scores as well.
Results
In tibial and femur T2 mapping ROI values for the cellular group were decreased in compared with acellular group at 24 months (P > 0.05) this difference tended to be lower in both groups after 24 months with not significant difference. In the clinical scores, Tegner & KOOS-QOL increased significantly at 12m while Lysholm got better at 18 m (p > 0.05) in the cellular group (Tab.1). The rest of the scales didn`t show significant difference between groups (p > 0.05). Second look at 12-months showed complete integration without rupture or loss of the implant in any group (Fig. 1)
Conclusion
Polyurethane meniscal scaffolds enhanced with mobilized mesenchymal stem cells shows benefit only the first 24 months, after this time this group does not show any advantage either in the protection of articular cartilage or in clinical scores over acellular scaffolds.