Page 97 - IJB-9-1

International Journal of Bioprinting Progress in bioprinting of bone

ROB-laden PEG4K-Clay scaffolds was significantly larger
amniotic fluid-derived stem cells, SVF: Stromal vascular fraction, NHOst: Normal human osteoblasts, iMSCs: Immortalized hTERT-overexpressing MSCs, ucMSCs: Fetal MSCs from umbilical cord,
Bone morphogenetic protein 4, MSCs: Mesenchymal stem cells, HUVECs: Human umbilical vein endothelial cells, hTMSCs: Human nasal inferior turbinate tissue-derived MSCs, hAFSCs: Human
than that of other groups.
PLGA: Poly (lactic-co-glycolic acid), PEG: Poly (ethylene oxide), CMC: Carboxymethyl cellulose, COL-I: Collagen type I, HA: Hyaluronic acid, PCL: Polycaprolactone, TCP: Tricalcium phosphate,
Laponite, CPC: Calcium phosphate cement, PEGDA: Poly ethylene glycol diacrylate, ALG/MC: Alginate-methylcellulose blend, LPN: Laponite, MSNs : Mesoporous silica nanoparticles, BMP-4:
PLA: Polylactic acid, GelMA: Gelatin methacrylate, VEGF: Vascular endothelial growth factor, MeHA: Methacrylated hyaluronic acid, PVA: Polyvinyl alcohol, RGD: Arginylglycylaspartic acid,
Table 1 summarizes the studies on extrusion-based
BMSCs: Bone marrow stem cells, ADSCs: Adipose-derived stem cells, rBMSCs: Rat BMSCs, hMSCs: Human MSCs, DPSCs: Dental pulp stem cells, SD: Sprague Dawley, ROBs: Rat osteoblasts
nHAp: Nano-hydroxyapatite, pDNA: Plasmid DNA, TGF-b3: Transforming growth factor-beta 3, nSi: Nanosilicate, kCA: Kappa-carrageenan, AMP: Amorphous magnesium phosphate, LAP:
Zonal structure -- -- bone bioprinting and the properties of the bioprinted bone
PEO: Polyethylene glycol, PPO: Poly (phenylene oxide), BCP: Biphasic calcium phosphate, DNA: Deoxyribonucleic acid, BMP-2: Bone morphogenetic protein 2, HAp: Hydroxyapatite,
constructs.
3.2. Droplet-based bioprinting of bone
Viability -- >90% at 1 day Campos et al. [130] applied DBB to bone reconstruction, and
thermo-responsive agarose hydrogels with COL-I were
inkjet-printed at different concentrations. By increasing
the agarose content in agarose/collagen composites, more
precise contours could be captured in the bioprinted tissue,
Compressive modulus 30.7 ± 9.1 MPa 20% PEG4K-7% Clay: 0.47 MPa 20% PEG10K-7% Clay: 0.98 MPa since the viscosity and mechanical stiffness of the bioinks
were improved, therefore facilitating their printability.
However, softer hydrogels resulted in the greater elongation
of MSCs after osteogenic differentiation. Cells survived

Mechanical reinforcement Laponite XLG nanoclay in the bioprinting and preserved the mesenchymal
phenotype, as confirmed by high cell viability (>98%),
immunostaining of vimentin+ and CD34−, ALP activity,
and bone-related gene expression.
--
3.3. Laser-based bioprinting of bone
Pore size (porosity) -- -- Using the digital light processing-based 3D bioprinting
generated a construct
technique, Anada et al.
[131]
that consists of two rings, which are an outer ring of
octacalcium phosphate (OCP) and GelMA imitating the
cortical shell as well as an inner ring of HUVEC spheroids
and GelMA imitating the bone marrow. On increasing the
Animal model Male rats concentration of OCP, MSC differentiation was enhanced,
resulting in increased ALP activity, and the vascularization
was observed in hydrogels, which contained HUVEC
--
spheroids in combination with GelMA.
Bernal et al. [132] developed an optical-tomography-
Cell source hMCSs ROBs inspired volumetric printing (VBP) apparatus, which
enables structures of complex shapes to be bioprinted
within seconds, and used in bone remodeling. This method
overcomes the limitations of bioprinting such as a long
PEGDA, Laponite XLG nanoclay, It was used to bioprint an anatomical bone trabecular
printing time and difficulty of printing complex structures.
model containing MSCs, in which the smallest feature was
145 μm, and endothelial colony-forming cells (ECFCs)
and MSCs were further added into the pores to form a

Materials CPC, ALG/MC HA heterocellular structure, where the vascular formation was
seen after a 3-day culture.
Table 1. (Continued) Study Ahlfeld et al. [128] Zhai et al. [129] Heo et al. [133] used AAB technology to control the precise
3.4. Aspiration-assisted bioprinting of bone
printing of osteogenically differentiated hMSC/HUVEC
spheroids. The method allowed the printed spheroids to
tightly self-assemble and retain their original shape without

Volume 9 Issue 1 (2023) 89 disintegration. The survival rate of cells in hMSC/HUVEC
https://doi.org/10.18063/ijb.v9i1.628