7 research outputs found
In vivo biofunctional evaluation of hydrogels for disc regeneration
Purpose Regenerative strategies aim to restore the original
biofunctionality of the intervertebral disc. Different
biomaterials are available, which might support disc
regeneration. In the present study, the prospects of success
of two hydrogels functionalized with anti-angiogenic peptides
and seeded with bone marrow derived mononuclear
cells (BMC), respectively, were investigated in an ovine
nucleotomy model.
Methods In a one-step procedure iliac crest aspirates
were harvested and, subsequently, separated BMC were
seeded on hydrogels and implanted into the ovine disc. For
the cell-seeded approach a hyaluronic acid-based hydrogel
was used. The anti-angiogenic potential of newly developed
VEGF-blockers was investigated on ionically crosslinked
metacrylated gellan gum hydrogels. Untreated discs
served as nucleotomy controls. 24 adult merino sheep were
used. After 6 weeks histological, after 12 weeks histological
and biomechanical analyses were conducted.
Results Biomechanical tests revealed no differences
between any of the implanted and nucleotomized discs. All
implanted discs significantly degenerated compared to
intact discs. In contrast, there was no marked difference
between implanted and nucleotomized discs. In tendency,
albeit not significant, degeneration score and disc height
index deteriorated for all but not for the cell-seeded
hydrogels from 6 to 12 weeks. Cell-seeded hydrogels
slightly decelerated degeneration.
Conclusions None of the hydrogel configurations was
able to regenerate biofunctionality of the intervertebral
disc. This might presumably be caused by hydrogel
extrusion. Great importance should be given to the development
of annulus sealants, which effectively exploit the
potential of (cell-seeded) hydrogels for biological disc
regeneration and restoration of intervertebral disc
functioningThis work was supported by the EU-project Disc Regeneration (NMP3-LA-2008-213904). Technical assistance of Iris Baum and the whole animal surgery team of the Institute of Orthopaedic Research and Biomechanics, Ulm, are gratefully acknowledged. DDAHA hydrogels were kindly provided by Cristina Longinotti (DDAHA, Anika Therapeutics, Abano Therme, Italy)
Meniscal Scaffolds - Preclinical Evidence to Support their Use: A Systematic Review
Arthroscopic meniscal treatment is the most common procedure performed in the orthopedic practice. Current management of meniscal pathology relies on different therapeutic options, ranging from selective meniscectomy, suturing, and to meniscal replacement by using either allografts or scaffolds. The progresses made in the field of regenerative medicine and biomaterials allowed to develop several meniscal substitutes, some of those currently used in the clinical practice. Before reaching the clinical application, these devices necessarily undergo accurate testing in the animal model: the aim of the present manuscript is to systematically review the scientific evidence derived by animal model results for the use of meniscal scaffolds, in order to understand the current state of research in this particular field and to identify the trends at preclinical level that may influence in the near future the clinical practice. Thirty-four papers were included in the present analysis. In 12 cases the meniscal scaffolds were used with cells to further stimulate tissue regeneration. With the exception of some negative reports regarding dacron-based scaffolds, the majority of the trials highlighted that biomaterials and bio-engineered scaffolds are safe and could play a beneficial role in stimulating meniscal healing and in chondral protection. With regard to the benefits of cell augmentation, the evidence is limited to a small number of studies and no conclusive evidence is available. However, preclinical evidence seems to suggest that cells could enhance tissue regeneration with respect to the use of biomaterials alone, and further research should confirm the translational potential of cell-based approach