Three-Dimensional Coculture of Meniscal Cells and Mesenchymal Stem Cells in Collagen Type I Hydrogel on a Small Intestinal Matrix—A Pilot Study Toward Equine Meniscus Tissue Engineering

Abstract

Meniscal injuries are the most frequently encountered soft tissue injuries in the equine stifle joint. Due to the inherent limited repair potential of meniscal tissue, meniscal injuries do not only affect the meniscus itself but also lead to impaired joint homeostasis and secondary osteoarthritis. The presented study compares 3D coculture constructs of primary equine mesenchymal stem cells (MSC) and meniscus cells (MC) seeded on three different scaffolds-a cell-laden collagen type I hydrogel (Col I gel), a tissue-derived small intestinal matrix scaffold (SIS-muc) and a combination thereof-for their qualification to be applied for meniscus tissue engineering. To investigate cell attachment of primary MC and MSC on SIS-muc matrix SEM pictures were performed. For molecular analysis, lyophilized samples of coculture constructs with different cell ratios (100% MC, 100% MSC, and 50% MC and 50% MSC, 20% MC, and 80% MSC) were digested and analyzed for DNA and GAG content. Active matrix remodeling of 3D coculture models was indicated by matrix metalloproteinases detection. For comparison of tissue-engineered constructs with the histologic architecture of natural equine menisci, paired lateral and medial menisci of 15 horses representing different age groups were examined. A meniscus phenotype with promising similarity to native meniscus tissue in its GAG/DNA expression in addition to Col I, Col II, and Aggrecan production was achieved using a scaffold composed of Col I gel on SIS-muc combined with a coculture of MC and MSC. The results encourage further development of this scaffold-cell combination for meniscus tissue engineering.

Structure—Function relationships of equine menisci

“…The histologic architecture, the fibre types and orientation, the size and shape of the fibrochondrocytes, as well as differences in vascularization between the three zones and layers we described in detail in [ 30 ]. In the current paper we focused on the two major matrix components (Col I fibres and GAGs) and the question whether differences in their arrangement, network formation and distribution at regions A, B and C, between medial and lateral menisci and between the three age groups may account for differences in biomechanical properties.…”

“…Maybe integration of a higher number of samples would have led to significance of potential minimal differences. Also investigation of potential differences of the biomechanical properties of the three different zones (axial to abaxial) which are consistent with differences in collagen composition, collagen fibre architecture, GAG content and vascularisation [ 30 ] rather than regions (A, B and C) could be productive to reveal biomechanical site-specific differences.…”

“…Of the thirteen paired medial and lateral menisci which underwent histologic evaluation, samples were taken from the three anatomic regions A, B and C ( Fig 1 ) and processed as described previously [ 30 ].…”

“…Staining for Haematoxylin and Eosin, to illustrate fibre networks, as well as the thickness of the SL, Safranin O / Fast Green and Alcian blue, to show ECM composition and Van Gieson, for illustration of collagen fibre orientation, were performed as described previously [ 30 ].…”

Novel Approaches in Meniscal Repair Utilizing Mesenchymal Stem Cells, New Generation Bioscaffolds and Biological Adhesives as Cell Delivery Vehicles

“…MSCs sourced from a number of tissues including synovial tissues [142][143][144][145], adipose [146,147], bone marrow [45, [148][149][150]] and blood vessels [151] have been applied in a number of applications to promote meniscal repair [44-48, [152][153][154][155][156][157][158] (Table 1). Co-cultures of meniscal cells and MSCs have also been examined in meniscal repair strategies [43, 159,160]. Furthermore, a diverse range of bio scaffolds have been developed containing CS have been developed to promote MSC differentiation in-vivo for varied applications in repair biology [161] (Table 3).…”