Experimental study on allografts of amniotic epithelial cells in calcaneal tendon lesions of sheep

Department of Veterinary Clinical Sciences, University of Teramo, Teramo, Italy.
Veterinary Research Communications (Impact Factor: 1.24). 06/2010; 34 Suppl 1(S1):S117-20. DOI: 10.1007/s11259-010-9396-z
Source: PubMed


An experimental protocol was designed to study the survival and behaviour of an allograft of amniotic epithelial cells (AECs) in an ovine model. The study was conducted on three healthy adult sheep. A core lesion was created in both calcaneal tendons under ultrasound (US) guidance by injecting 400 UI of Type 1A collagenase diluted in 0.6 ml saline. The AECs were obtained from a 60-80-day-old fetus and cultured under standard conditions. After 15 days of collagenase treatment, 2 x 10(6) AECs stained with a vital membrane fluorescent probe (PHK26) were injected under US guidance in 500 microl saline solution into the lesion of one limb. The contralateral untreated limb was used as a control. Animals were euthanatized 7 (1) and 30 (2) days later. Histological analyses performed on explanted tendons clearly demonstrate that AECs survived for at least 1 month inside the lesion without any adverse reactions. The damaged tissue of the treated tendons showed a high number of reparative cells in active proliferation that were accumulating collagen within the extracellular matrix. In addition, after 1 month, the neo-collagen began to be organized into parallel arrays of fibers oriented along the longitudinal axis of the tendon.

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    • "All the oAECs with a stable proliferation index, a conserved expression pattern and the ability to undergo in vitro tenogenic cell lineage differentiation, were then stained with the Red Fluorescent Cell Linker dye, PKH26, before storing the cells in vials of 2.5 Â 10 6 by cryopreservation in liquid nitrogen. Cryopreserved, labeled cells were then thawed, washed and suspended in aMEM without any growth factors and FCS before their use either in preclinical (Muttini et al., 2010) or clinical settings. "
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    • "Currently, many studies performed have been seeking more effective treatments for injuries to the tendons, such as the employment of an allograft of amniotic epithelial cells (Muttini et al., 2010), platelet-rich plasma that contains growth factors (Bosch et al., 2010), metrenperone (Oryan et al., 2010) or mesenchymal stem cells (Schnabel et al., 2009). The aim of these new treatments was to reduce the recurrence of injuries through a remodeling of the extracellular matrix at the site of a tendon injury. "
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