The aim of this study was to evaluate the cultivation potential of cartilage taken from the debrided edge of a chronic lesion of the articular surface. A total of 14 patients underwent arthroscopy of the knee for a chronic lesion onthe femoral condyles or trochlea. In addition to the routine cartilage biopsy, a second biopsy of cartilage was taken from the edge of the lesion. The cells isolated from both sources underwent parallel cultivation as monolayer and three-dimensional (3D) alginate culture. The cell yield, viability, capacity for proliferation, morphology and the expressions of typical cartilage genes (collagen I, COL1; collagen II, COL2; aggrecan, AGR; and versican, VER) were assessed. The cartilage differentiation indices (COL2/COL1, AGR/VER) were calculated. The control biopsies revealed a higher mean cell yield (1346 cells/mg vs 341 cells/mg), but similar cell proliferation, viability and morphology compared with the cells from the edge of the lesion. The cartilage differentiation indices were superior in control cells: COL2/COL1 (threefold in biopsies (non-significant)); sixfold in monolayer cultures (p = 0.012), and 7.5-fold in hydrogels (non-significant), AGR/VER (sevenfold in biopsies (p = 0.04), threefold (p = 0.003) in primary cultures and 3.5-fold in hydrogels (non-significant)). Our results suggest that the cultivation of chondrocytes solely from the edges of the lesion cannot be recommended for use in autologous chondrocyte implantation.
COBISS.SI-ID: 28151513
There is a critical need to increase the size of bone grafts that can be cultured in vitro for use in regenerative medicine. Perfusion bioreactors havebeen used to improve the nutrient and gas transfer capabilities and reducethe size limitations inherent to static culture, as well as to modulate cellular responses by hydrodynamic shear. Our aim was to understand the effects of medium flow velocity on cellular phenotype and the formation of bone-like tissues in three-dimensional engineered constructs. We utilized custom-designed perfusion bioreactors to culture bone constructs for 5 weeks using a wide range of superficial flow velocities (80, 400, 800, 1,200, and 1,800 microm/s), corresponding to estimated initial shear stresses ranging from 0.6 to 20 mPa. Increasing the flow velocity significantly affected cell morphology, cell-cell interactions, matrix production and composition, and theexpression of osteogenic genes. Within the range studied, the flow velocities ranging from 400 to 800 microm/s yielded the best overall osteogenic responses. Using mathematical models, we determined that even at the lowest flow velocity (80 microm/s) the oxygen provided was sufficient to maintain viability of the cells within the construct. Yet it was clear that this flow velocity did not adequately support the development of bone-like tissue. The complexity of the cellular responses found at different flow velocities underscores the need to use a range of evaluation parameters to determine the quality of engineered bone. Bioeng.
COBISS.SI-ID: 28231897
In their alfa – granules, platelets contain several growth factors (platelet derived growth factor (PDGF), TGF-α & β (transforming growth factor alpha & β), EGF (epidermal growth factor), FGF (fibroblast growth factor), IGF (insulin growth factor), PDEGF (platelet derived epidermal growth factor), PDAF (platelet derived angiogenesis factor), IL-8 (interleukin-8), TNF-α (tumour necrosis factor alpha), CTGR (connective tissue growth factor), GM-CSF (granulocyte macrophage colony stimulating factor), KGF (keratinocyte growth factor), in Ang-2 (angiopoetin) and at least 60 other biologically active substances that can be used in regenerative medicine for tissue healing. The chapter of monography describes all aspects of platelet physiology, instructions for gel production and the current medical applications.
COBISS.SI-ID: 29257177