Mesenchymal stromal cell delivery as a potential therapeutic strategy against COVID-19: Promising evidence from in vitro results

Figure 2 Comprehensive characterization of characteristics of stimulated Wharton’s Jelly and bone marrow mesenchymal stromal cells. A: Experimental workflow; B: Morphological analysis of characteristics of unstimulated and stimulated Wharton’s Jelly (WJ) and bone marrow-mesenchymal stromal cells (BM-MSCs). Original magnification 20 ×, scale bars = 50 μm; C: Determination of cell proliferation and viability. Statistically significant differences were observed in cell proliferation between stimulated and unstimulated WJ-MSCs (P < 0.05) and stimulated and unstimulated BM-MSCs (P < 0.05). No statistically significant difference was observed in cell viability either in an unstimulated or stimulated state (P = 0.873); D: Immunophenotypic analysis of stimulated and unstimulated WJ and BM-MSCs. Over 95% of WJ and BM-MSCs in both states expressed CD73, CD90, CD105, CD29, and CD340, and less than 2% expressed CD34 and CD45; E: Determination of HLA-G isoforms (HLA-G1, G5, and G7) in unstimulated and stimulated MSCs from both sources; F: Indirect immunofluorescence against HLA-G1 in combination with DAPI stain was performed on unstimulated and stimulated WJ and BM-MSCs. Original magnification 63 ×, scale bars = 10 μm. BM: Bone marrow; MSCs: Mesenchymal stromal cells; WJ: Wharton’s Jelly.