Table 1.
Priming strategies
|
Cell type
|
Benefits
|
Mechanisms
|
Reference
|
|
Hypoxia: | |||||
1%–3% O2 | DPSCs; PDLSCs | Improve survival | Upregulation of stem cell markers; Regulation of metabolic activities; Activation of the p38/MAPK and ERK/MAPK pathways | [66,67,70] | |
DPSCs; SHEDs; SCAPs | Promote angiogenesis | Increase proangiogenic factors releasing | [60,62,63] | ||
Culture conditions | DPSCs; SCAPs; PDLSCs | Enhance differentiation potential | Upregulation of odontoblastic markers | [68,69,71,72] | |
PDLSCs | Enhance anti-inflammation effect | Upregulation of IL-37 | [73] | ||
Pharmacological stimulation | DPSCs | Promote angiogenesis | Increase intracellular levels of HIF-1α | [51,64,65] | |
PDLSCs | Improve survival but inhibit differentiation potential | [49] | |||
3D culture: | |||||
Single cell type | DPSCs; PDLSCs | Enhance differentiation potential | Upregulation of odontoblastic markers | [83,84,87] | |
Coculture | DPSCs and ECs | Promote angiogenesis | [86] | ||
Mechanical and physical stimuli: | |||||
LIPUS | DPSCs; PDLSCs | Increase proliferation | Activation of MAPK pathway | [94,95] | |
Cyclic mechanical tension | DPSCs | Promote osteogenic differentiation; Increase cytokines release | Upregulation of osteoblastic markers | [98,99] | |
Uniaxial stretch | DPSCs | Increase proliferation but inhibit osteo/odontogenic differentiation | [96,97] | ||
Cytokines | |||||
SDF-1 | DPSCs; PDLSCs | Promote cell migration | Activation of SDF-1/CXCR4 axis; Autophagy; Activation of AKT and GSK3β/β-catenin pathways | [104,107,109,110] | |
PDLSCs | Anti-apoptosis | Activation of ERK pathway | [105] | ||
DPSCs; PDLSCs | Enhance differentiation potential | Upregulation of odontoblastic markers; Upregulation of osteoblastic markers | [106,108,111] | ||
TNF-α | Enhance immunomodulatory effects | Mediated by TNF/TNFR2 signaling | [124-126] | ||
Enhance osteogenic differentiation | Activation of p38 pathway; Activation of miR-21/STAT3 and NF-κB pathway | [127-129] | |||
Inhibit differentiation potential (50-100 ng/mL) | Activation Wnt/β-catenin pathway | [132] | |||
G-CSF; IFN-γ | DPSCs | Promote cell migration | [114,121,122] | ||
DPSCs | Enhance or inhibit differentiation potential depend on cytokines concentration | [116,120,121] | |||
Preconditioning mediators | growth factors | ||||
bFGF | DPSCs | Promote angiogenesis | [136,139-141] | ||
DPSCs; PDLSCs | Enhance differentiation potential on dose dependent (20-50 ng/mL in vitro; 15 μg/mL-5 mg/mL in vivo) | Upregulation of odontoblastic markers; Upregulation of osteoblastic markers; Upregulation of neural markers; Activation of FGFR/MEK/ERK1/2 and BMP/BMPR signaling pathways | [137,138,141,144,149-151] | ||
DPSCs | Promote anti-inflammation effect | Altered cytokines expression; | [146-148] | ||
IGF-1 | PDLSCs | Promote cell survival | [165] | ||
DPSCs | Anti-apoptosis | [164] | |||
DPSCs; PDLSCs | Enhance differentiation potential | Upregulation of osteoblastic markers; Upregulation of odontoblastic markers; Activation of mTOR pathway; Target of EphrinB1 | [160-162,166] | ||
Sox-2 | DPSCs | Improve cell migration | [171] | ||
Bcl-2; Oct-4 | DPSCs | Improve cell survival | Upregulation of stemness-rated genes; | [168,169] | |
Genetic modification | Foxo-1 | PDLSCs | Promote anti-inflammation effect | Resistance to oxidative stress | [175] |
BMP family; Runx2 | DPSCs; SCAP; DFCs | Enhanced differentiation potential | Upregulation of osteoblastic markers; Upregulation of odontoblastic markers | [178-184] |
DPSCs: Dental pulp stem cells; PDLSCs: Periodontal ligament stem cells; SHED: Stem cells from human exfoliated deciduous teeth; SCAP: Stem cells from the apical papilla; LIPUS: Low-intensity pulsed ultrasound; SDF-1: Stromal cell-derived factor-1; TNF-α: Tumor necrosis factor-α; G-CSF: Granulocyte-colony stimulating factor; IFN-γ: Interferon-γ; bFGF: Basic fibroblast growth factor; IGF-1: Insulin-like growth factor-1; Bcl-2: B-cell lymphoma 2.