High Harvest Yield, High Expansion, and Phenotype Stability of CD146 Mesenchymal Stromal Cells from Whole Primitive Human Umbilical Cord Tissue

Figure 1

In situ examination of human umbilical cords. (a) UCs range in length up to 60 cm; shown is a cut 10 cm portion with UC blood removed. (b) Histology of 10 micron thick cryosections stained with Alcian blue. (c) Schematic of UC cross-section. Green dots represent cells; all other structures are as indicated. (d) Detection of CD34, CD144, CD146, CD44, CD105, CD73, and CD90. CD34 and CD144 are expressed only in the endothelial lumen of the UC vessels. CD146 expression is present in both the vascular and perivascular regions, but not in the bulk of the WJ. CD44- and CD105-positive cells are found in the WJ, perivascular region, and in the vessels. CD105 is also in the lumen. A low level of CD73 expression is found throughout the vessels and high in the region just beneath the epithelium (*75% positivity only in the region just below epithelium). CD90 positivity was detected in all regions, except the endothelium. Scale bars on whole vessel images represent 200 𝜇m; all others represent 100 𝜇m. (e) The percentage of cells expressing these markers was determined by immunostaining: (PV: perivascular region).