Fig. 1.

MSCs produce and release TNFα for functional maintenance. a–c Examination of mRNA expression levels, protein expression levels, and secreted concentrations of TNFα in different cell types. N = 3. For quantification of Western blotting, two-tailed Student’s t test was used for comparisons between different cell types and MSCs. d Calcein labeling for bone formation analysis in WT and TNFα^−/− mice (N = 5). Scale bar = 50 μm. e Oli red O staining for bone marrow adiposity in WT and TNFα^−/− mice (N = 5). Scale bar = 150 μm. f–i Functional analyses of MSCs according to CFU, BrdU labeling, osteogenic, and adipogenic differentiation. TNFα and RANKL were added at 1 ng·mL⁻¹. N = 5. Scale bars = 100 μm. j Examination of protein expression levels and secreted concentrations of TNFα. N = 3. TAPI-2 was used to inhibit TACE at 120 nmol·L⁻¹. k–n Functional analyses of MSCs according to CFU, BrdU labeling, and osteogenic and adipogenic differentiation. N = 3. Scale bars = 100 μm. o Diagram showing the production and release of TNFα for the functional maintenance of MSCs. For quantification of Western blotting, a two-tailed Student’s t test was used for the comparison between the treatment and WT groups. *P < 0.05. N.S. not significant. Data represent the mean ± SD