Efficacy of serum-free cultured human umbilical cord mesenchymal stem cells in the treatment of knee osteoarthritis in mice

Figure 1 Collection of human umbilical cord mesenchymal stem. A: Serum-free human umbilical cord mesenchymal stem, scale bar = 200 μm; B: Serum-cultured human umbilical cord mesenchymal stem cells, scale bar = 200 μm. N-hUCMSCs: Serum-free human umbilical cord mesenchymal stems; S-hUCMSCs: Serum-cultured human umbilical cord mesenchymal stem cells.

Figure 2 Average body weight of mice in each group. The weight of each group of mice showed an upward trend after surgical modeling. N-hUCMSCs: Serum-free human umbilical cord mesenchymal stems; S-hUCMSCs: Serum-cultured human umbilical cord mesenchymal stem cells; HA: Hyaluronic acid.

Figure 3 Reduced interleukin-6 and interleukin-1β expression in the experimental group. A: Baseline analysis: There was no statistically significant difference in the initial levels of interleukin (IL)-1β among the groups of animals; B: Baseline analysis: There was no statistically significant difference in the initial levels of IL-6 among the groups of animals; C: Model validation: The level of IL-1β in the model control group was significantly higher than that in the sham surgery group (blank control group); D: Model validation: The level of IL-6 in the model control group was significantly higher than that in the sham surgery group (blank control group); E: Experimental endpoints: The level of IL-1β in the experimental group was significantly higher than that in the model control group; F: Experimental endpoints: The level of IL-6 in the experimental group was significantly higher than that in the model control group. ^aP < 0.05, comparison with the sham operated group; ^bP < 0.01, comparison with the sham operated group; ^cP < 0.05, comparison with the model control group; ^dP < 0.01, comparison with the model control group. N-hUCMSCs: Serum-free human umbilical cord mesenchymal stems; S-hUCMSCs: Serum-cultured human umbilical cord mesenchymal stem cells; IL: Interleukin.

Figure 4 The experimental group favored the repair of cartilage tissue. A and B: Model validation: In the control group, the integrity of the articular cartilage was disrupted, the cartilage surface became rough and uneven, the synovial tissue in the joint cavity proliferated significantly, and the number of osteoclasts in the bone marrow cavity increased; C: Experimental endpoints: The number of chondrocytes in the treatment group was significantly increased compared to the model control group; D: Experimental endpoints: The Mankin score of the model control group was significantly higher than that of the sham surgery group (blank control group). ^bP < 0.01, comparison with the sham-operated group. N-hUCMSCs: Serum-free human umbilical cord mesenchymal stems; S-hUCMSCs: Serum-cultured human umbilical cord mesenchymal stem cells.

Figure 5 X-ray. Radiograph of the knee joint before the anatomical experiment. The experimental group can mice with reduced formation of osteoid in the knee joint. N-hUCMSCs: Serum-free human umbilical cord mesenchymal stems; S-hUCMSCs: Serum-cultured human umbilical cord mesenchymal stem cells.

Figure 6 Histological images of cartilage tissue of knee joints of each group. The collagen II staining was strongest in the sham surgery group, weakest in the model control group, weakest in matrix metalloproteinase-1 and matrix metalloproteinase-13 staining in the sham surgery group (blank control group), and strongest in the model control group. MMP: Matrix metalloproteinase; N-hUCMSCs: Serum-free human umbilical cord mesenchymal stems; S-hUCMSCs: Serum-cultured human umbilical cord mesenchymal stem cells.

Figure 7 Western bolt. A: Western bolt original picture; B: The model control group had the lowest expression level of collagen II, while the blank control group had the highest expression level; C: The model control group had the highest expression level of matrix metalloproteinase-1, while the blank control group had the lowest expression level; D: The model control group had the highest expression level of matrix metalloproteinase-13, while the blank control group had the lowest expression level. ^bP < 0.01, comparison with the sham-operated group; ^cP < 0.05, comparison with the modeled control. MMP: Matrix metalloproteinase; N-hUCMSCs: Serum-free human umbilical cord mesenchymal stems; S-hUCMSCs: Serum-cultured human umbilical cord mesenchymal stem cells.