Stem cells and bFGF in tendon healing: Effects of lentiviral gene transfer and long-term follow-up in a rat Achilles tendon defect model

Abstract

BackgroundThe influence of stem cells and lentiviral expression of basic fibroblastic growth factor (bFGF) on tendon healing and remodelling was investigated in an in-vivo long-term (12 weeks) rat Achilles tendon defect model.MethodsIn sixty male Lewis rats, complete tendon defects (2.4 mm) were created and either left untreated (PBS) or treated by injection of stem cells lentivirally expressing the enhanced green fluorescence marker gene eGFP (MSC-LV-eGFP) or basic fibroblast growth factor bFGF (MSC-LV-bFGF). Tendons were harvested after 12 weeks and underwent biomechanical and (immuno)-histological analysis.ResultsAfter 12 weeks the mean ultimate load to failure ratio (treated side to contralateral side) in biomechanical testing reached 97 % in the bFGF-group, 103 % in the eGFP-group and 112 % in the PBS-group. Also in the stiffness testing both MSC groups did not reach the results of the PBS group.Histologically, the MSC groups did not show better results than the control group. There were clusters of ossifications found in all groups. In immunohistology, only the staining collagen-type-I was strongly increased in both MSC groups in comparison to PBS control group. However, there were no significant differences in the (immuno)-histological results between both stem cell groups.ConclusionThe biomechanical and (immuno)-histological results did not show positive effects of the MSC groups on tendon remodelling in a long-term follow-up. Interestingly, in later stages stem cells had hardly any effects on biomechanical results. This study inspires a critical and reflected use of stem cells in tendon healing.

Improved tendon healing using bFGF, BMP-12 and TGFβ1 in a rat model

“…Much evidence supports the use of GFs to enhance tendon healing (Docheva et al, 2015;Evans, 1999;Molloy et al, 2003;Sharma and Maffulli, 2006), but numerous issues remain to be resolved, including which GFs to use and when and how to deliver them. Single GFs provide little benefit or only incremental improvement to tendon healing in vitro and in animal models (Chan et al, 2000;Feng et al, 2007;Forslund and Aspenberg, 2001;Gelberman et al, 2016;Kashiwagi et al, 2004;Klein et al, 2002;Kraus et al, 2016;Kraus et al, 2014;Majewski et al, 2008;Majewski et al, 2012;Tang et al, 2008;Wang et al, 2005b), suggesting that mixtures of different GFs may be necessary to modulate the complex process of tendon healing in a substantial manner. This may explain why ACS and PRP show some ability to improve tendon healing (Aspenberg and Virchenko, 2004;Bosch et al, 2010;de Almeida et al, 2012;Gosens et al, 2012;Majewski et al, 2009;Parafioriti et al, 2011;Schnabel et al, 2007;Seijas et al, 2013).…”

“…Moreover, bFGF gene transfer increases expression of type I and type III collagen in vitro (Feng et al, 2007;Wang et al, 2005b). However, promising results demonstrating improved tendon healing by bFGF gene transfer (Tang et al, 2008) are not reproducible (Kraus et al, 2016;Kraus et al, 2014). In a small series of 8 rabbits, Achilles tendons heal better than controls if treated with bFGF (Najafbeygi et al, 2017).…”

“…This selection combines GFs that collectively are mitogenic, chemotactic, angiogenic and morphogenetic, while stimulating matrix synthesis. All of the three GFs are already tested individually, resulting in modest improvement in tendon repair (Chan et al, 2000;Feng et al, 2007;Forslund and Aspenberg, 2001;Kashiwagi et al, 2004;Klein et al, 2002;Kraus et al, 2016;Lou et al, 2001;Majewski et al, 2008;Majewski et al, 2012;Tang et al, 2008;Wang et al, 2005b).…”

Effectiveness of Ozone Therapy on Tendon Healing: An Experimental Study in Generated Achilles Tendon Injury Model in Rats

“…In the current study, the focus was particularly on the injury of the tendon tissue. Philippou A et al reported that the local production of IGF-1 is particularly important in regeneration, hypertrophy, proliferation, and differentiation of skeletal muscles 17) . In another study by Duman et al, the effects of rectal ozone therapy on femur fracture in rats were evaluated 18) .…”

Differentiation of Human Amniotic Mesenchymal Stem Cells into Human Anterior Cruciate Ligament Fibroblast Cells by In Vitro Coculture

“…bFGF belongs to the heparin-binding growth factor family. Previous studies [ 37 , 38 ] have reported that bFGF and TGF can be used to improve the bioactivity of osteoblasts and promote the aggregation of fibroblast and inflammatory cells, further enhancing the formation of blood vessels and granulation tissue.…”