Objective To study the variation of CD105+/CD166+ cells and its multilineage potential in early osteoarthritis (OA) cartilage so as to lay a foundation for cartilage repair and pathologic cartilage remodeling in arthritis. Methods The knee OA model was established in the right knee of 30 adult New Zealand rabbits (8-12 months old). The chondrocytes were harvested from normal cartilage of the left knee (group A), OA cartilage of the right knee at 2 weeks (group B), at 4 weeks (group C), and at 8 weeks (group D) after modeling, and BMSCs were used in group E for the expression of CD105 and CD166. The percentage of CD105+/CD166+ cells in each group was counted by flow cytometry, and CD105+/CD166+ cells were isolated and purified by magnetic-activated cell sorting. The expressions of CD105 and CD166 were observed in 5 groups by laser scanning confocal microscope. Chondrogenesis, osteogenesis, and adipogenesis were evaluated with Alcian blue cytochemistry and collagen type II immunohistochemistry, by detecting the deposition of calcium, and with oil red O staining, respectively. Results The percentage of CD105+/CD166+ cells in group A, B, C, and D was significantly lower than that in group E (P lt; 0.05); it was significantly higher in groups B, C, and D than in group A (P lt; 0.05), and in group D than in groups B and C (P lt; 0.05), but no significant difference was found between groups B and C (P gt; 0.05). Laser scanning confocal microscope results confirmed the expressions of CD105+ and CD166+ cells in groups A, B, C, D, and E, no obvious difference in expression was shown among 5 groups. At 1 week after chondrogenic induction, positive expressions of proteoglycan and collagen type II were observed in 5 groups, no obvious difference was noticed among 5 groups. At 2 weeks after osteogenic induction, calcium level in group E was significantly higher than that in groups A, B, C, and D (P lt; 0.05), but no significant different was found among groups A, B, C, and D (P gt; 0.05). At 4 weeks after adipogenic induction, there were more red lipid droplets in group E than in groups A, B, C, and D. Conclusion CD105+/CD166+ cells in early OA cartilage increase, which show chondrogenic differentiation potential.
Objective To investigate the treatment and therapeutic efficacy of intra-articular meniscal cysts by arthroscopy. Methods From January 2005 to December 2009, 9 cases of intra-articular meniscal cysts were treated by arthroscopy, including 5 males and 4 females, with an average age of 33.8 years (range, 24-46 years). Six patients suffered in left knees, 3 in right ones. Just 1 case had trauma history, the others had no obvious predisposing causes. The average course of the disease was 24.2 months (range, 4-36 months). The Lysholm score was (74.2 ± 11.6) points. Arthroscopy showed that the locations of cysts were the anterior horn of lateral meniscus in 8 cases and the anterior horn of medial meniscus in 1 case; all being single cyst (of them, 3 being multilocular cyst). Results All incisions healed primarily with no compl ications of infection and joint effusion. All 9 patients were followed up from 3 to 48 months with an average of 12.7 months. Preoperative symptoms disappeared or reduced and the range of motion of the knee returned to normal. TheLysholm score was (95.1 ± 3.4) points after 3 months of operation, showing significant difference (P lt; 0.01) when compared with the socre before operation. According to assessment standard described by Choy, the treatment outcome was excellent in 6 cases, good in 2 cases, and general in 1 case; the excellent and good rate was 88.9%. No recurrence was found during follow-up. Conclusion Arthroscopic surgery shows the advantages to maintain good function of knee for the treatment of meniscal cyst, it is the best choice for intra-articular meniscal cysts because of its mini-trauma, rapid recovery, thorough treatment and less recurrence. Simultaneously, partial or tatol meniscectomy or menicus repairing under arthroscopy is performed.