Table 1: Semiquantitative score of histological findings, immunoreactivity of stain, and motion analysis according to treatment groups at 4 weeks after injection.

Groups (injection regimens)
0.2 mL NS (G1-SAL)0.2 mL PDRN (G2-PDRN)0.2 mL MSC (G3-MSC)0.2 mL MSC + 0.2 mL PDRN (G4-MSC + PDRN)

Histological score
 MTS0.0 ± 0.00.9 ± 0.562.2 ± 0.423.0 ± 0.0
 Anti-type collagen 10.2 ± 0.421.1 ± 0.312.1 ± 0.313.0 ± 0.0
 BrdU0.88 ± 0.841.54 ± 1.132.05 ± 1.162.54 ± 1.11
 PCNA1.27 ± 0.912.10 ± 1.072.70 ± 1.083.11 ± 1.00
 VEGF1.27 ± 0.942.00 ± 1.072.64 ± 0.923.18 ± 0.79
 PECAM-11.68 ± 0.932.22 ± 0.922.86 ± 0.983.36 ± 0.75
Motion analysis
 Walking distance (cm)4728.37 ± 137.275416.62 ± 323.276343.62 ± 213.576932.37 ± 107.74
 Fast walking time (%)5.62 ± 1.428.32 ± 0.3410.33 ± 2.4812.07 ± 1.77
 Mean walking speed (cm/sec)6.3 ± 0.578.36 ± 0.399.62 ± 1.7812.3 ± 1.13

Values are the mean ± SD. The immunoreactivity of MTS and anti-type 1 collagen antibody stain and proportion of BrdU-, PCNA-, VEGF-, and PECAM-1-positive cells were scored as detailed in Materials and Methods. NS: normal saline; MSC: human umbilical cord blood-derived mesenchymal stem cell; PDRN: polydeoxyribonucleotide; G1-SAL: 0.2 mL normal saline group; G2-PDRN: 0.2 mL PDRN; G3-MSC: 0.2 mL UCB-MSCs; G4-MSC + PDRN: 0.2 mL UCB-MSCs with 0.2 ml PDRN; MTS: Masson’s trichrome stain; BrdU: bromodeoxyuridine; PCNA: proliferating cell nuclear antigen; VEGF: vascular endothelial growth factor; PECAM-1: platelet endothelial cell adhesion molecule. one-way ANOVA, Tukey’s post hoc test among groups.