Umbilical cord as a mesenchymal stem cell source for treating joint pathologies

Figure 1 Characterization of the mesenchymal stem cell population from human umbilical cord stroma. A: Flow cytometry of the principal mesenchymal stem cell (MSC) markers. In each diagram, at the top is the name of the marker, at the bottom the fluorochrome used and at the top right the percentage of positive cells; B: Immunofluorescence analysis of CD44 and CD90 in a human umbilical cord cryosection; DAPI was used to label cell nuclei. (Magnification 20 ×); C: Alizarin red stain (upper) and Oil red O stain (lower) of spheroids engineered from MSCs differentiated in two defined media, proving their pluripotency. OM: Osteogenic medium; AM: Adipogenic medium; DMEM: Control medium with no defined cytokines to promote differentiation.

Figure 2 Representative diagrams of the methodology for spheroid chondrogenesis. Diagram showing culture times used for a new method for the induction of chondrogenesis. Representative sections of immunohistochemical analyses for collagen type 2 (COL2) expression from spheroids engineered from Wharton´s jelly mesenchymal stem cells at different times of chondrogenesis are shown. (Magnification 10x). AA: Ascorbic acid; MTG: Monothioglycerol; RA: Retinoic acid; KO serum: Knock out serum (GIBCO™); TGFβ-3: Recombinant human transforming growth factor-β3; TRANS: Transferrine; DEX: Dexamethasone.

Figure 3 Cellular therapy. A: Graphic illustrating the regeneration of a chondral lesion in vitro; B: Wharton’s jelly mesenchymal stem cells (MSCs) growing in vitro in a human osteochondral punch lesion over 90 d in chondrogenic medium with added transforming growth factor β3. Modified Masson staining shows the MSCs differentiating in the lesion (Magnification 2 ×, 4 × and 20 ×); C: Graphic portraying the technique of intra-articular injection of MSCs into an injured joint to treat lesions in vivo.