Virtual Issue: Stem Cell in Bioprinting

International Journal of Bioprinting presents the latest state-of-art of stem cell in bioprinting.

Wai Yee Yeong


The human body comprises of specific group of cells that are capable of numerous division, giving rise to daughter cells that are more directed towards specific lineage and specialized function. Examples of such high potency stem cells includes the totipotent zygote, embryonic stem cells, hematopoietic stem cells, and mesenchymal stem cells (MSCs). Of which, MSCs have been widely used due to the spectrum of specialized mesenchymal tissues that can be differentiated into. Such tissues include bone, cartilage, muscle and other connective tissues. MSCs can be isolated from various locations such as bone marrow tissues, adipose tissues and skin tissues[1]. Similarly, induced Pluripotent Stem Cells (iPSCs) derived from any somatic cell can be attained with relatively high yield[2].

Scaffold designs provide topographical cues that can influence stem cell morphology, proliferation and differentiation. As stem cells are sensitive to topographical cues, additional biological cues may not be required to elicit such cellular responses[2]. Controlling pore sizes[1] and groove depths[3] of scaffolds provide cues to induce stem cells towards osteogenic differentiation and cardiomyocyte phenotypes respectively.

Two distinct methods have been shown in stem cell delivery for bioprinted constructs. Stem cells can either be seeded on bioprinted scaffolds[4] or mixed in bioinks for controlled deposition[1,3]. Matrigel containing adipose derived MSCs were deposited as droplets between PCL/bioactive glass composite filaments printed into grid structures[1]. Similarly, soluble gelatin bioink comprising of MSCs was dispensed on top of a pre-etched substrate patterned with grooves, inducing MSCs alignment and differentiation[3].

With increase design freedom using computer-assisted technology, a multitude of scaffold designs and materials can be fabricated within a bioprinted constructs. Conditioning multipotent MSCs with varying geometrical cues produce differentiated cells of different phenotypes. Recognizing this potential, we compiled several papers from the published issues to present the latest state-of-art of stem cell in bioprinting. The papers are:

 

References

[1]Murphy C, Kolan K, Li W, et al., 2017, 3D bioprinting of stem cells and polymer/bioactive glass composite scaffolds for bone tissue engineering. Int J Bioprint, 3(1): 54-64. https://dx.doi.org/10.18063/IJB.2017.01.005

[2]Mehrban N, Teoh G Z, Birchall M A, 2016, 3D bioprinting for tissue engineering: Stem cells in hydrogels. Int J Bioprint2(1): 6-19. https://dx.doi.org/10.18063/IJB.2016.01.006

[3]Bhuthalingam R, Lim P Q, Irvine S A, et al., 2015, A novel 3D printing method for cell alignment and differentiation. Int J Bioprint, 1(1):57-65. http://dx.doi.org/10.18063/IJB.2015.01.008

[4]Wang W, Caetano G F, Chiang W-H, et al., 2016, Morphological, mechanical and biological assessment of PCL/pristine graphene scaffolds for bone regeneration. Int J Bioprint, 2(2): 95-105. http://dx.doi.org/10.18063/IJB.2016.02.009