Bioreactor systems in tissue engineering

Bioreactor systems play a crucial role in tissue engineering by providing a controlled and dynamic environment for the growth and development of engineered tissues. These systems mimic the physiological conditions necessary for tissue formation, ensuring that the cells receive adequate nutrients, oxygen, and mechanical stimulation (1).

Here are some key aspects of bioreactor systems in tissue engineering:

Perfusion bioreactors Perfusion bioreactors are designed to provide a continuous flow of culture media through the tissue construct. This flow helps maintain uniform nutrient and oxygen distribution, removes waste products, and stimulates the development of a functional vascular network within the engineered tissue (2).

Rotating wall bioreactors Rotating wall bioreactors use a rotating vessel to create a low-shear, three-dimensional culture environment. This type of bioreactor is often used for growing large, complex tissues like cartilage or engineered organs. The rotation prevents cells from settling, encourages uniform cell distribution, and promotes tissue maturation (3).

Spinner flask bioreactors Spinner flask bioreactors are a simple and cost-effective option. They consist of a flask with a magnetic stir bar that rotates at a controlled speed. While not as sophisticated as other bioreactor types, spinner flasks can be used for culturing cells and small tissue constructs in suspension, making them suitable for early-stage experiments and cell expansion (4).

Microfluidic bioreactors

Microfluidic bioreactors use microfabrication techniques to create small-scale, precisely controlled environments for cell culture. They are well-suited for studies involving cell-cell interactions, tissue patterning, and drug testing. Microfluidic systems offer the advantage of fine-tuned control over the microenvironment, enabling the creation of complex tissue structures (5).

Bioreactor monitoring and control

Modern bioreactor systems often include advanced sensors and control systems to monitor and regulate critical parameters such as pH, temperature, oxygen concentration, and nutrient levels. This ensures that the tissue culture conditions remain optimal for cell growth and tissue development (1).

Bioreactor-grown organs

Researchers are exploring the use of bioreactor systems to grow entire organs, such as hearts and livers, for transplantation. These projects involve intricate bioreactor designs and a deep understanding of organ-specific tissue engineering principles (6).

References

1. Selden C, Fuller B. Role of Bioreactor Technology in Tissue Engineering for Clinical Use and Therapeutic Target Design. Bioengineering (Basel). 2018 Apr 24;5(2):32. doi: 10.3390/bioengineering5020032. PMID: 29695077; PMCID: PMC6027481.

2. Gaspar DA, Gomide V, Monteiro FJ. The role of perfusion bioreactors in bone tissue engineering. Biomatter. 2012 Oct-Dec;2(4):167-75. doi: 10.4161/biom.22170. PMID: 23507883; PMCID: PMC3568103.

3. Gardner JK, Herbst-Kralovetz MM. Three-Dimensional Rotating Wall Vessel-Derived Cell Culture Models for Studying Virus-Host Interactions. Viruses. 2016 Nov 9;8(11):304. doi: 10.3390/v8110304. PMID: 27834891; PMCID: PMC5127018.

4. Jeske R, Lewis S, Tsai AC, Sanders K, Liu C, Yuan X, Li Y. Agitation in a Microcarrier-based Spinner Flask Bioreactor Modulates Homeostasis of Human Mesenchymal Stem Cells. Biochem Eng J. 2021 Apr;168:107947. doi: 10.1016/j.bej.2021.107947. Epub 2021 Jan 27. PMID: 33967591; PMCID: PMC8104359.

5. Karimi M, Bahrami S, Mirshekari H, Basri SM, Nik AB, Aref AR, Akbari M, Hamblin MR. Microfluidic systems for stem cell-based neural tissue engineering. Lab Chip. 2016 Jul 5;16(14):2551-71. doi: 10.1039/c6lc00489j. PMID: 27296463; PMCID: PMC4935609.

6. Bijonowski BM, Miller WM, Wertheim JA. Bioreactor design for perfusion-based, highly-vascularized organ regeneration. Curr Opin Chem Eng. 2013 Feb 1;2(1):32-40. doi: 10.1016/j.coche.2012.12.001. PMID: 23542907; PMCID: PMC3610919.