Imagine a world where broken bones heal faster, damaged cartilage regenerates, and even lost organs can be grown. This is the promise of tissue engineering. Scaffold designing plays a major role in tissue engineering which could solve these problems.
As the name suggests, a scaffold is a structure that provides a framework to the main body, supports it, and maintains its shape. For example, our skeleton acts as a scaffold which provides shape to the body and has many functions.
Scaffold designing is a very integral part of tissue engineering as it acts as a temporary, supportive framework that is designed to help and facilitate the growth and development of new tissue.
Tissue Engineering and Its Focus
The primary focus of tissue engineering seeks to replace damaged tissues with appropriate cells, constructs, and biological systems. This field has helped in overcoming problems such as tissue loss, organ transplantation, autologous grafts, and synthetic limitations.
But organ transplantation faces a shortage of donors and the need for immunosuppressants. Autologous grafting can be limited by tissue availability and donor site complications. Artificial replacements or artificially made scaffolds often lack the complexity of natural tissues.
These problems can be countered by using advanced tissue engineering methods.
Structure of Scaffold
Scaffold consists of pores of different sizes which are measured in μm, in which the cells are introduced. These offer structural support and help in the growth of new tissue-like formations.
Moreover, these scaffolds serve as a platform for the optimum release of growth factors and drug applications. The successful design of scaffolds for tissue engineering purposes is very important.
We need to make sure that the materials used while designing the scaffold are non-infectious, do not harm the patient, and the body should be able to accept the scaffold.
Biomaterials Used in Scaffold
Hence, scientists use biomaterials such as gelatine, chitosan, and alginate, which are the most common biodegradable polymers used in engineering applications. Collagen present in the peptides helps in cell attachment and migration.
These polymers can be easily modified and exhibit various properties such as cell-adhesion and also resist the in-vivo forces thus maintaining their structure during the tissue development process. They also show high efficiency in transporting drugs to the desired sites in the body.
These biomaterials are cheap and can be extracted from the marine ecosystem as they are abundant and easily processed. This makes bone regeneration therapies more effective, easier, and cost-efficient.
Advantages of Scaffold
The advantages of using scaffold include bone regeneration, cartilage repair, drug delivery, wound healing, and nerve regeneration.
Peripheral nerve tissue engineering scaffolds act as a template to guide and support nerve regeneration. Scaffold is also useful in ligament replacement, bone defect fracture, and organ repair.
Disadvantages and Challenges
As simple as it sounds, scaffold designing has its downside as well. One challenge includes post-fabrication cell-seeding. In this process, the cells are placed inside the pores of the scaffold which grow and proliferate, but this process itself is time-consuming and inefficient.
The other problem is that due to the biodegradable nature of scaffold, the cell-seeding process faces the problem of scaffold contraction when there is a scaffold-tissue stiffness mismatch, and the elasticity is inadequate.
Additionally, every scaffold is different from each other based on its properties, one of them being the different load-bearing strength, thus limiting their use in load-bearing applications.
Cell death after implantation in the body is also one of the major challenges which the scientists are going through, as cells while in diffusion can survive only at a distance of ∼100–200 μm away from the source of nutrient supply.
Strategies
Different strategies have been explored which can provide cells, in newly engineered tissue, the appropriate amount of nutrients and oxygen so that they could form new cells and vessels.
We can achieve this by using O2 generating biomaterials as they have been exhibiting great results when used as a part of 3D-bioprinting tissue constructs.
With the use of autologous cells and biocompatible materials, we can avoid these issues.
With the help of reaction-modulating agents such as anti-inflammatory agents embedded or integrated in the biomaterial, we can optimize reactions towards implanted biodegradable materials.
Frequently Asked Questions (FAQs)
Q1. What is scaffold modelling in tissue engineering?
Scaffold modelling is the design of 3D frameworks that support new tissue growth.
Q2. Why are scaffolds important in tissue engineering?
Scaffolds provide structural support and guide the regeneration of damaged tissues.
Q3. What materials are commonly used for scaffolds?
Gelatine, chitosan, alginate, and collagen are widely used biomaterials.
Q4. Can scaffolds replace organ transplantation?
Scaffolds can reduce reliance on organ transplants by promoting tissue repair and regeneration.
Q5. What are the main advantages of scaffolds?
They aid in bone regeneration, cartilage repair, wound healing, and drug delivery.
Q6. What challenges are faced in scaffold design?
Key challenges include cell death, scaffold contraction, and load-bearing limitations.
Q7. How do scaffolds promote bone regeneration?
They act as frameworks that guide cells to grow and form bone tissue.
Q8. Are scaffold materials safe for the human body?
Yes, scaffolds are designed from biocompatible, non-infectious, and biodegradable materials.
Q9. Can scaffolds be customized for patients?
Yes, 3D bioprinting allows scaffolds to be customized to patient-specific needs.
Q10. What is the future of scaffold-based tissue engineering?
The future lies in advanced biomaterials and 3D printing for organ and tissue regeneration.
References
- Howard, D., Buttery, L. D., Shakesheff, K. M., & Roberts, S. J. (2008). Tissue engineering: strategies, stem cells and scaffolds. Journal of Anatomy, 213(1), 66–72. https://doi.org/10.1111/j.1469-7580.2008.00878.x
- Ashammakhi, N., GhavamiNejad, A., Tutar, R., Fricker, A., Roy, I., Chatzistavrou, X., Hoque Apu, E., Nguyen, K. L., Ahsan, T., Pountos, I., & Caterson, E. J. (2022). Highlights on Advancing Frontiers in Tissue Engineering. Tissue Engineering. Part B, Reviews, 28(3), 633–664. https://doi.org/10.1089/ten.TEB.2021.0012
- Zhang, H., Wu, X., Quan, L., & Ao, Q. (2022). Characteristics of Marine Biomaterials and Their Applications in Biomedicine. Marine Drugs, 20(6), 372. https://doi.org/10.3390/md20060372
- Howard, D., Buttery, L. D., Shakesheff, K. M., & Roberts, S. J. (2008). Tissue engineering: strategies, stem cells and scaffolds. Journal of Anatomy, 213(1), 66–72. https://doi.org/10.1111/j.1469-7580.2008.00878.x
- Alini, M., Li, W., Markovic, P., Aebi, M., Spiro, R. C., & Roughley, P. J. (2003). The potential and limitations of a cell-seeded collagen/hyaluronan scaffold to engineer an intervertebral disc-like matrix. Spine, 28(5), 446–453. https://doi.org/10.1097/01.BRS.0000048672.34459.31
- Zhang, Y., He, F., Zhang, Q., Lu, H., Yan, S., & Shi, X. (2023). 3D-Printed Flat-Bone-Mimetic Bioceramic Scaffolds for Cranial Restoration. Research (Washington, D.C.), 6, 0255. https://doi.org/10.34133/research.0255
Authors
Mr. Aditya Sashi (Fourth year B. Tech. Biotechnology Student), Dr. Amit Kumar Singh & Dr. Latika Shendre*
Microbial Diversity Research Center,
Dr. D. Y. Patil Biotechnology and Bioinformatics Institute,
Dr. D. Y. Patil Vidyapeeth,
Tathawade, Pune - 411033, Maharashtra, India.
*Email: latika.shendre@dpu.edu.in