Starting from a public dataset
Kornsuthisopon, Osathanon, and colleagues at Chulalongkorn University asked how the Notch ligand Jagged1 drives human dental pulp stem cells (hDPSCs) toward mineralized tissue. Rather than generating new sequencing data, they reanalyzed their group’s earlier RNA-seq dataset (GEO GSE94989), in which hDPSCs were cultured on indirectly immobilized Jagged1 at 10 nM for 24 hours, with or without the Notch inhibitor DAPT. A targeted reanalysis of extracellular matrix and integrin genes showed these pathways respond to Jagged1 and that the response is attenuated when Notch is blocked. Among integrin subunits, ITGB3 stood out as one of the most prominently upregulated (Kornsuthisopon et al. 2026, Fig. 1A).
Jagged1 turns on ITGB3 through Notch
The team validated the reanalysis in primary hDPSCs isolated from extracted third molars of healthy adults (passages 3 to 6, independent donor cultures as biological replicates). Immobilized Jagged1 raised the Notch target genes HES1 and HEY1 in a dose-dependent manner, and ITGB3 mRNA rose significantly at 10 nM while ITGA6 fell at 1 and 10 nM; ITGA1, ITGA5, and ITGA8 did not change. Over a 7-day time course, ITGB3 tracked HES1 and HEY1 (exploratory Spearman r = 0.86 and 0.91, P < .001), and immunofluorescence confirmed higher ITGβ3 protein on Jagged1-coated surfaces. Endogenous JAG1 and NOTCH1 were unchanged, so the activation came from the immobilized ligand rather than upregulated receptor or ligand expression (Kornsuthisopon et al. 2026, Fig. 1).
Blocking integrins blunts mineralization
To test whether integrin adhesion is functionally required, the group used cilengitide, an RGD-based antagonist of αvβ3 and αvβ5 integrins, at 3 to 1000 nM. Cilengitide did not affect viability, proliferation, migration, or basal apoptosis over the tested range. Under 14-day osteogenic induction, however, it reduced Alizarin Red mineral deposition, significantly at 80, 500, and 1000 nM, and 1000 nM significantly lowered ALP and COL1A1 expression (Kornsuthisopon et al. 2026, Fig. 2). On Jagged1-coated surfaces the same pattern held: migration was unaffected, mineralization fell significantly at 1000 nM, and RUNX2 was significantly down, but 1000 nM also increased late-stage apoptosis, so the high-dose mineralization deficit partly reflects cell loss rather than a differentiation-specific effect (Kornsuthisopon et al. 2026, Fig. 3). ERK1/2 phosphorylation, tested as a downstream readout, was variable and not consistently suppressed by cilengitide.
Silencing ITGB3 tells a different story
The pharmacology and the genetics diverge. siRNA against ITGB3, with knockdown confirmed at mRNA and protein, reduced basal mineralization and significantly lowered ALP, COL1A1, and RUNX2 under osteogenic induction. Yet on Jagged1-coated surfaces, ITGB3-silenced cells mineralized normally, with no significant difference in calcium deposition or osteogenic gene expression compared with Jagged1-treated controls (Kornsuthisopon et al. 2026, Fig. 4). In other words, Jagged1-induced osteogenesis survived the loss of the very subunit Jagged1 upregulates. Because cilengitide disrupts multiple RGD-dependent integrin interactions, while siRNA leaves residual ITGβ3 protein and other heterodimers untouched, the authors conclude the drug’s effect cannot be attributed to ITGβ3 alone, and compensatory integrin changes remain unexamined.
Boundary and relevance to pulp-dentin repair
Everything here is in vitro, in cells from a small number of healthy adult donors, with endpoints at days chosen for culture convenience rather than clinical healing times. The study is also candid about its edges: donor variation by sex and age was not stratified, FAK and Akt signaling were not measured, and two authors are associate editors of the journal that published the work. For the pulp-dentin repair program, the value is mechanistic: Jagged1-Notch signaling, already a known pro-osteogenic cue in dental pulp stem cells, appears to run in parallel with, or upstream of, an integrin-dependent adhesion program rather than through a single integrin subunit. The authors suggest a concrete next step, pairing RGD-bearing adhesion motifs with immobilized Jagged1 in scaffolds, which is testable but so far untested.
Provenance: primary source read in full at International Dental Journal via PMC13508636; analysis written for the daily pass. See /method/ for the site’s evidence standards.