Kim IH1#, Jeon M2#, Lee YH2, Shin JS3, Lee T2, Lee SK3, Cheon K4 and Song JS1,2*
1Department of Pediatric Dentistry, College of Dentistry, Yonsei University, Korea
2Oral Science Research Center, College of Dentistry, Yonsei University, Korea
3Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Korea
4Department of Pediatric Dentistry, University of Alabama at Birmingham, USA
#These authors contributed equally to this work
Background: Hypoxia-Inducible Factor 1 (HIF-1) alpha (HIF-1α) is known to be expressed in hypoxia and affects stemness and bone differentiation. Protein Transduction Domains (PTDs) safely and effectively deliver proteins into cells. This study combined HIF-1α delta Oxygen-Dependent Degradation Domain–Transcription Modulation Domain (ntHIF-1α-ΔODD-TMD) with the PTD and then used it to treat Stem cells from Human Exfoliated Deciduous teeth (SHED) to determine its effect on stemness and bone differentiation. Methods: The SHED were treated using PDT-conjugated ntHIF-1α-ΔODD-TMD, and its effects on STRO-1 expression, cytotoxicity, stemness-related gene expression, and osteogenic differentiation were confirmed. These were also transferred to 5-week-old mice in order to confirm the effects in vivo after recellularization of SHED treated using ntHIF-1α-ΔODD-TMD on decellularized tooth specimens. After 9 weeks, they were sacrificed to confirm the expression of genes related to bone differentiation and angiogenesis. Results: ntHIF-1α-ΔODD-TMD increased the expression levels of STRO-1, HIF-1α-related genes, and stemness-related genes in SHED. Osteogenic differentiation was also increased both in vitro and in vivo. Conclusion: These results suggest that ntHIF-1α-ΔODD-TMD maintains or increases the stemness of SHED and also increases the osteogenic potential. SHED have previously been found to have excellent proliferative but low differentiation capacities compared with other cells. However, properly using ntHIF-1α-ΔODD-TMD increases the osteogenic potential of SHED, indicating the potential of using SHED as a useful source for hard-tissue regeneration.
Hypoxia-inducible factor 1 alpha; Stem cells from human exfoliated deciduous teeth; Protein transduction domain; Stemness; Osteogenic differentiation
Kim IH, Jeon M, Lee YH, Shin JS, Lee T, Lee SK, et al. HIF-1α Overexpression Using a Protein Transduction Domain to Increase the Osteogenic Potential of SHED. J Dent Oral Biol. 2023; 8(3): 1215. ISSN: 2475-5680.