Preconditioning of Rat Bone Marrow-Derived Mesenchymal Stromal Cells with Toll-Like Receptor Agonists

Figure 6

Analysis of the effect of the conditioned medium from unstimulated and LPS-preconditioned rBM-MSCs on neurite outgrowth. (a) Representative photomicrographs of dorsal root ganglion (DRG) explants immunolabeled with TuJ1 antibody (green) 24 h after incubation with fresh control medium supplemented with 5% fetal bovine serum (Control Medium group), bone marrow-derived mesenchymal stromal cell- (rBM-MSC-) conditioned medium (MSC CM group), rBM-MSC-conditioned medium+axitinib (a VEGF receptor inhibitor) (MSC CM+axitinib group), lipopolysaccharide- (LPS-) preconditioned rBM-MSC-conditioned medium (MSC-LPS CM group), or LPS-preconditioned rBM-MSC-conditioned medium+axitinib (MSC-LPS CM+axitinib group). Fresh control medium supplemented with 5% fetal bovine serum and nerve growth factor was used as a positive control (control medium+NGF group). Nuclear staining with 4,6-diamidino-2-phenylindole (DAPI) in blue. Scale bar: 100 μm. (b) Quantitative analysis of neurite density in DRG explants showing that LPS preconditioning did not affect the capacity of rBM-MSC-conditioned medium to induce neurite growth in dorsal root ganglion sensory neurons ( explants per group; rBM-MSCs from only 1 animal were used in this experiment to reduce donor-related variability). ; one-way ANOVA followed by the Newman-Keuls post hoc test.

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