Enhancement of the repair of meniscal wounds in the red–white zone (middle third) by the injection of bone marrow cells in canine animal model

Abstract

Bone marrow stem cells (BMSCs) can differentiate into several cells that participate in the healing of meniscal wounds. To test this hypothesis, we examined the effects of injected BMSCs on the healing of meniscal wounds. Autologous BMSCs from eight adult dogs were injected into meniscal wounds (knee joints). After 12 weeks, the healing process was clinically and immunomorphologically evaluated using: (i) histochemical stains (haematoxylin and eosin, Masson trichrome and periodic acid-Schiff) and (ii) immunoperoxidase staining methods (CD3, CD79a, CD68, CD31 and alpha smooth-muscle actin for T, B lymphocytes, macrophages, endothelial cells and smooth-muscle lineage). Complete (six vs. three), partial (one vs. one) and no healing (one vs. four animals) of the meniscal wounds were observed in the injected and noninjected menisci. As compared with the noninjected menisci, examination of the tissues from the injected ones revealed: (i) marked angiogenesis (microvessel density: 3.22 +/- 0.66 vs. 6.50 +/- 2.10); (ii) chondrogenesis; (iii) prominent immune cell infiltrate (4.07 +/- 0.78 vs. 9.56 +/- 1.69, 8.33 +/- 0.77 vs. 3.67 +/- 1.00 and 4.38 +/- 0.62 vs. 11.1 +/- 1.43 for the total numbers of immune cells, lymphocytes and macrophages, respectively); and (iv) proliferation of the fibroblasts with marked deposition of collagen fibres (2.0 +/- 0.84 vs. 2.66 +/- 0.48). These values were statistically significantly higher for the injected menisci as compared with the noninjected ones (P >/= 0.05). Autologous BMSCs can improve meniscal wound healing. Whether this improvement occurs through BMSC differentiation into cells operational in the repair process, the release of certain mediator or other unknown mechanisms mandates further investigations.

Early loss of subchondral bone following microfracture is counteracted by bone marrow aspirate in a translational model of osteochondral repair

“…However, some authors questioned the difference of the cellular components between native and centrifuged marrow aspirate2634. The native bone marrow aspirate was even proven to be superior to centrifuged bone marrow aspirate for the healing of meniscal lesions in a dog model35. Another possible explanation is the short observation period in the present study.…”

“…Another possible explanation is the short observation period in the present study. In previous studies with encouraging results of native or centrifuged bone marrow aspirate, evaluations were performed at 3 months35, 8 months4, and even 10 years32.…”

A novel hypothesis: The application of platelet-rich plasma can promote the clinical healing of white-white meniscal tears

“…Some new techniques focus on meniscus tissue engineering such as cell-based therapy and gene therapy, tissue-engineered collagen meniscus implant, or the use of a degradable scaffold for meniscus regeneration. Studies [2,3] are being conducted to find the optimal method, but these have not yet been applied to humans. Thus the controversies about white-white meniscal tears have not ceased.…”

Ultrastrong and flexible hybrid hydrogels based on solution self-assembly of chitin nanofibers in gelatin methacryloyl (GelMA)

“…6). hMSCs are ideal cell sources for cardiovascular tissue engineering because they can differentiate into smooth muscle cells and endothelial cells in vitro 26, 27 and in vivo . 28, 29 Typically, co-culture of HUVECs and MSCs results in the formation of robust functional vascular networks within the first week.…”