Bio-based fibres for human damaged part replacements and active wound healing

4.6.2018

“What is the role of fibres in biomedical applications?"

“How are bio-based fibres related to the implantation of tissue or organs to a human body?”

“Can the healing capabilities of wound dessings be improved by adding properties to the fibres?”

 

Tissue engineering and regenerative medicine has emerged as a multidisciplinary field that combines the principles of engineering, biology and medicine. A major goal of this field is to create constructs with controlled structures and mechanical properties. These constructs can be either applied to the human body surface or used inside the body. Examples of fibrous construct interfaced with the body are bandages or dressings utilized for covering and treating wounds and damaged tissues. The fabrics applied to the body surface should provide a mechanical support to the wound and damaged tissues until the new tissue is formed and the wound is closed. Therefore, it is essential to reach a proper mechanical strength when designing fibrous dressings.

Figure 1. Structural arrangement of fibres in a blood vessel.

Implantation of the fibrous constructs in the body is done when a replacement for a diseased or damaged tissue or organ is required. All tissues and organs in the body are composed of various fibres with different structures (as shown in the figure) which provide proper functionality to the tissue. The implants should mimic the structure, biological and mechanical properties of the native tissues in order to have long-term functionality in the body.

The structure of the native tissue can be mimicked by the structure of scaffolds in the engineered constructs. Scaffolds are porous 3D materials that provide mechanical stability and structure to the newly-formed tissue and allow the cells to adhere, expand and create a new tissue.  These scaffold materials can be seeded with cells prior to implantation or can be used as an acellular (without cells) construct that can attract the host cells after implantation. The extracellular matrix fibres produced by cells can be aligned with the fibres in the scaffold. Therefore, it is essential to design a scaffold with a native-like structure to create a functional native-like tissue. To create scaffolds with different fibrous structures, different methods, such as textile technologies, are used to fabricate scaffolds from the fibres.

Figure2. Impact of the scaffold structure on the alignment of cells (Lim et al. Arch Plast Surg 2014).

Finally, depending on the application for which the scaffold is going to be used, different bioactive components or drugs can be incorporated onto the fibres. For example, incorporation of antimicrobial components to wound dressings can prevent infection in a wide range of wounds, and  incorporation of growth factors in a scaffold can stimulate growth of the cells and formation of the new tissue. While a huge progress has been made in the field of fibre-based scaffolds used for medical applications, fibre-based implants used in the clinic are only limited to a very few applications. The main reason is that they mostly don’t have a native-like structure and properties. Therefore, in the future studies, it is important to develop advanced biomaterials with tunable physical and chemical properties capable of a controlled delivery of different biomolecules and to produce and fabricate the fibres to a 3D native-like construct.

 

Writer:

Samaneh Ghazanfari, Maastricht University

WP leader of WP4, Biomedical Applications and supervisor in IRP4