Adipose-derived stem cell therapies for bone regeneration

ABSTRACT

Introduction: Cell-based therapies exploit the heterogeneous and self-sufficient biological environment of stem cells to restore, maintain and improve tissue functions. Adipose-derived stem cells (ASCs) are, to this aim, promising cell types thanks to advantageous isolation procedures, growth kinetics, plasticity and trophic properties. Specifically, bone regeneration represents a suitable, though often challenging, target setting to test and apply ASC-based therapeutic strategies.

Areas covered: ASCs are extremely plastic and secrete bioactive peptides that mediate paracrine functions, mediating their trophic actions in vivo. Numerous preclinical studies demonstrated that ASCs improve bone healing. Clinical trials are ongoing to validate the clinical feasibility of these approaches. This review is intended to define the state-of-the-art on ASCs, encompassing the biological features that make them suitable for bone regenerative strategies, and to provide an update on existing preclinical and clinical applications.

Expert opinion: ASCs offer numerous advantages over other stem cells in terms of feasibility of clinical translation. Data obtained from in vivo experimentation are encouraging, and clinical trials are ongoing. More robust validations are thus expected to be achieved during the next few years, and will likely pave the way to optimized patient-tailored treatments for bone regeneration.

KEYWORDS:

• Adipose tissue
• adipose-derived stem cells
• ASCs
• regenerative medicine
• bone regeneration

Article highlights

• Adipose tissue houses multipotent somatic stem cells (aka adipose-derived stem cells, ASCs) residing in perivascular niches.

• Significant advancements in ASCs’ research have been achieved in the last decades, leading to improved knowledge of their biology and potentialities.

• ASCs exert osteoinductive properties, by secreting bioactive molecules and growth factors that mediate their paracrine trophic effects.

• ASCs are extremely plastic and proved to be capable of inducing bone regeneration in distinct animals models.

• Strict regulatory issues are to be met in order to achieve a safe and efficient clinical translation of the numerous experimental data on ASC-based therapies.

• Clinical trials are ongoing to provide the final confirmation of the correct and feasible exploitation of ASCs for the treatment of bone defects and of disorders characterized by impaired endogenous osteogenesis and bone remodeling.

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Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Additional information

Funding

The authors are funded by the Università Cattolica del Sacro Cuore, Linea D.1 – 2017. M Barba and W Lattanzi are also funded by National Institutes of Health (NIH) and National Institutes of Dental and Craniofacial Research (NIDCR) grant 2 R01-DE016886-06 while W Lattanzi also has receive grant support from the Ministero della Salute - Ricerca Finalizzata GR-2011-02348622.