New trends in spinal cord tissue engineering

ABSTRACT

Restoration of lost neuronal function after spinal cord injury still remains a considerable challenge for current medicine. Over the last decade, regenerative medicine has recorded rapid and promising advancements in stem cell research, genetic engineering and the progression of new sophisticated biomaterials as well as nanotechnology. This advancement has also been reflected in neural tissue engineering, where, along with the development of a new generation of well-designed biopolymer scaffolds, multifactorial therapeutic strategies are being validated in order to determine the greatest possible repair efficacy of the complex CNS pathophysiology. Much attention is currently focused on the designing of multifunctional polymer scaffolds as systems for targeted drug or gene delivery, electrical stimulation or as substrates creating a special micro-environment, promoting the growth and desired differentiation of various cell lines. In this review, the latest advances in biomaterial technology together with various combinatorial strategies designed to treat spinal cord injury treatment are summarized and discussed.

KEYWORDS:

• biomaterial
• cell therapy
• regenerative medicine
• spinal cord injury
• stem cells scaffold
• tissue engineering

Financial & competing interests disclosure

The financial support of the MEYS of the Czech Republic (LO1309) is gratefully acknowledged. The authors have no other 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 apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

New trends in spinal cord tissue engineering

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Activity evaluation: where 1 is strongly disagree and 5 is strongly agree.

• 1. Your patient is a 24-year-old man with spinal cord injury (SCI) after a motor vehicle crash. According to the review by Kubinová, which of the following statements about recent trends and approaches in scaffolds developed for neural tissue engineering in SCI is correct?

  • A Only nondegradable biomaterials have been investigated to construct scaffolds for SCI repair

  • B The most studied natural materials include alginate, hyaluronic acid, collagen, agarose, chitosan, fibrin, methylcellulose, and extracellular matrix-derived proteins

  • C Specific advanced synthetic biomaterials have been proven to be advantageous for central nervous system (CNS) repair in SCI

  • D Biocompatibility and controlled porosity are the only important physical–chemical properties of biomaterials considered for scaffold construction

• 2. According to the review by Kubinová, which of the following statements about recent trends and approaches in combining scaffolds with delivery of neurotrophic factors for neural tissue engineering in SCI is correct?

  • A Neurotrophic factors studied to date include neurotrophin-3 (NT-3), epidermal growth factor, basic fibroblast growth factor, brain-derived neurotrophic factor, chondroitinase, intracellular cyclic AMP, rolipram, and Shh

  • B Neurotrophic factors work only by stimulating differentiation of transplanted cells

  • C There is no experimental evidence supporting the use of NT-3

  • D Rolipram enhances axonal regeneration and improved functional recovery after SCI by stimulating phosphodiesterase 4

• 3. According to the review by Kubinová, which of the following statements about recent trends and approaches in the application of gene delivery to biomaterials, cellular therapy, and combined strategies for neural tissue engineering in SCI would most likely be correct?

  • A Combining scaffolds with neural stem/progenitor cells, neural stem cells, or mesenchymal stem cells does not appear to improve cell survival

  • B Human-induced pluripotent stem cells do not appear to hold much promise for SCI repair

  • C Applying gene delivery to biomaterials increases expression of a therapeutic gene or knockdown expression of a specific gene to manipulate the local environment within the lesion

  • D Using a combination of scaffolds with stem cells, growth factors, and other bioactive agents does not appear to have synergistic effects in SCI repair