Fetal derived embryonic-like stem cells improve healing in a large animal flexor tendonitis model

Abstract

IntroductionTendon injury is a common problem in athletes, with poor tissue regeneration and a high rate of re-injury. Stem cell therapy is an attractive treatment modality as it may induce tissue regeneration rather than tissue repair. Currently, there are no reports on the use of pluripotent cells in a large animal tendon model in vivo. We report the use of intra-lesional injection of male, fetal derived embryonic-like stem cells (fdESC) that express Oct-4, Nanog, SSEA4, Tra 1-60, Tra 1-81 and telomerase.MethodsTendon injury was induced using a collagenase gel-physical defect model in the mid-metacarpal region of the superficial digital flexor tendon (SDFT) of eight female adult Thoroughbred or Thoroughbred cross horses. Tendon lesions were treated one week later with intra-lesional injection of male derived fdESCs in media or media alone. Therapy was blinded and randomized. Serial ultrasound examinations were performed and final analysis at eight weeks included magnetic resonance imaging (MRI), biochemical assays (total DNA, glycosaminoglycan, collagen), gene expression (TNC, TNMD, SCX, COL1A1, COL3A1, COMP, DCN, MMP1, MMP3, MMP13, 18S) and histology. Differences between groups were assessed with Wilcoxon's rank sum test.ResultsCell survival was demonstrated via the presence of the SRY gene in fdESC treated, but not control treated, female SDFT at the end of the trial. There were no differences in tendon matrix specific gene expression or total proteoglycan, collagen or DNA of tendon lesions between groups. Tissue architecture, tendon size, tendon lesion size, and tendon linear fiber pattern were significantly improved on histologic sections and ultrasound in the fdESC treated tendons.ConclusionsSuch profound structural effects lend further support to the notion that pluripotent stem cells can effect musculoskeletal regeneration, rather than repair, even without in vitro lineage specific differentiation. Further investigation into the safety of pluripotent cellular therapy as well as the mechanisms by which repair was improved seem warranted.

CORR® ORS Richard A. Brand Award for Outstanding Orthopaedic Research: Engineering Flexor Tendon Repair With Lubricant, Cells, and Cytokines in a Canine Model

“…Embryonic stem cells, induced pluripotent stem cells, and adult mesenchymal stem cells [4,16,34] have been studied for their differentiation potential, function, regenerative capacity, and side effects. Adult mesenchymal stem cells most commonly are used clinically and experimentally.…”

Regenerative therapy for tendon and ligament disorders in horses: results of treatment with stemcells, blood products, scaffolds and growth factors – review of the literature and meta analysis

“…In einer Untersuchung mit ESCs waren Stichkanäle bei allen Kontrolltieren, jedoch nur bei 2/4 behandelten Tieren nachweisbar (Watts et al 2011 (Lutz et al 2009) zeigte für PRP eine kürzere Rekonvaleszenzeit bei einer geringeren Rate von Pferden, die wieder ihr ursprüngliches Leistungsniveau erreichten (s.u. ; Tab.…”

“…Wenngleich auch für die Verwendung allogener MSCs aus Knochenmark (Guest et al 2008) und Fettgewebe (Del Bue et al 2008 sowie allogener embryonaler und embryonal-ähnlicher Stammzellen (Guest et al 2010, Watts et al 2011 erste Untersuchungen an lebenden Pferden keine Hinweise auf immunologische bzw. tumoröse Komplikationen lieferten, liegen zur Verwendung allogener Zellen ebenso wie für die Gentherapie (Schnabel et al 2009, Taylor et al 2007) noch keine Langzeitergebnisse an einer größeren Anzahl von Patienten vor.…”

“…Das Ausweichen auf tierexperimentelle Studien am Pferd (Dahlgren et al 2002, Crovace et al 2007, Nixon et al 2008, Durgam et al 2009, Schnabel et al 2009, Guest et al 2010, Bosch et al 2010, Crovace et al 2010, Watts et al 2011, Carvalho et al 2011) ermöglicht im Idealfall die Erzeugung einer reproduzierbaren und vergleichbaren Läsion, den Vergleich mit Kontrolltieren und eine ausführliche feingewebliche, biochemische und biomechanische Analyse der behandelten Sehnen und somit eine Aussage über die Effekte auf die Sehnenstruktur. Derartige Studien sind mit sehr hohen Kosten verbunden und erstrecken sich deshalb oft nur auf eine relativ kurze Beobachtungszeit zwischen 6 Wochen und 6 Monaten (Nixon et al 2008, Guest et al 2010, Schnabel et al 2009, Watts et al 2011, Bosch et al 2010. Künstlich werden Sehnenschäden beim Pferd z.B.…”

Therapies intended for joint regeneration in the horse

“…The majority of clinical experience with the use of MSC in horses comes from the treatment of tendon and ligament injuries (Smith et al 2003, Richardson et al 2007, Guest et al 2008, Crovace et al 2010, Guest et al 2010, Watts et al 2011, Marfe et al 2012.…”