Fig. 6

KGN effect on wounded meniscus healing by an in vivo rabbit model. a A biopsy punch with 1 mm diameter was used for creating a wound on rabbit meniscus. b Three holes (1 mm diameter/hole, black arrows in b) were created in each meniscus of 12 rabbits by a biopsy punch. c Each wound in three rabbits was treated with 20 μl of saline (saline). d Each wound in 3 rabbits was treated with 5 μl of 100 μMKGN and 15 μl of saline (KGN). e Each wound in 3 rabbits was treated with 5 μl of 100 μMKGN and 5 μl of 10,000 U/ml thrombin and 10 μl of PRP (KGN+PRP gel). f Each wound in 3 rabbits was treated with 5 μl of saline, 5 μl of 10,000 U/ml thrombin, 10 μl of PRP, and 10,000 BMSCs (PRP+BMSC). g Each wound in 3 rabbits was treated with 5 μl of 100 μMKGN, 5 μl of 10,000 U/ml thrombin, 10 μl of PRP, and 10,000 BMSCs (KGN+PRP+BMSC). h Gross view of the wounded rabbit meniscus at day 90 post-surgery with saline treatments. i Gross view of the wounded rabbit meniscus at day 90 post-surgery with KGN treatment. j Gross view of the wounded rabbit meniscus at day 90 post-surgery with PRP-KGN gel treatment. k Gross view of the wounded rabbit meniscus at day 90 post-surgery with BMSCs-containing PRP gel treatment. l Gross view of the wounded rabbit meniscus at day 90 post-surgery with BMSCs-containing KGN-PRP gel treatment. Large unhealed wound areas were still found in the saline-treated meniscus (red arrows in h) and KGN-treated meniscus (red arrows in i). Although the wounds were healed with KGN-PRP gels, the new formed meniscus tissue was thinner (green arrow in j) than BMSCs-containing PRP-treated wound (k) and BMSCs-containing KGN-PRP gel-treated wound (l). There was no unhealed wound area found in the meniscus treated with BMSCs-containing PRP gel and BMSCs-containing KGN-PRP gel and the new formed meniscus in both groups was thick and healthy (k, l)