Journal: Frontiers in Bioengineering and Biotechnology

Article Title: Substrate stiffness modulates human gingival fibroblast paracrine signaling to promote osteogenic differentiation of human periodontal ligament cells

doi: 10.3389/fbioe.2026.1753774

Figure Lengend Snippet: Substrate stiffness regulates the behaviors of human gingival fibroblasts (HGFs). Real-time reverse transcription-polymerase chain reaction (RT-PCR) was performed to detect gene expression levels of (A) anti-inflammatory markers, IL4 , and IL10 , (B) matrix metalloproteinase markers, including MMP9 , and TIMP1 , (C) chemokine, CXCL12 . The expression of GAPDH was used as an internal control. Data were statistically analyzed by one-way ANOVA followed by Tukey’s multiple comparison tests ( n = 3: P < 0.05). (D) The expression of GAPDH was used as an internal control. Data were statistically analyzed by one-way ANOVA followed by Tukey’s multiple comparison tests ( n = 3: P < 0.05). (D) The protein expression of CXCL12 was detected by ELISA analysis. Data were statistically analyzed by one-way ANOVA followed by Tukey’s multiple comparison tests ( n = 4: P < 0.05). Data are presented as the mean ± standard deviation (SD), with different letters indicating statistically significant differences between multiple groups. IL4, interleukin 4; IL10, interleukin 10; MMP9, matrix metalloproteinase 9; TIMP1, tissue inhibitor of matrix metalloproteinases 1; CXCL12, CXC motif chemokine 12; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; PDMS, polydimethylsiloxane.

Article Snippet: CXCL12 protein in conditioned medium was measured by Human CXCL12/SDF-1α ELISA Kit (Quantikine, R&D systems.

Techniques: Reverse Transcription, Polymerase Chain Reaction, Reverse Transcription Polymerase Chain Reaction, Gene Expression, Expressing, Control, Comparison, Enzyme-linked Immunosorbent Assay, Standard Deviation

Journal: Frontiers in Bioengineering and Biotechnology

Article Title: Substrate stiffness modulates human gingival fibroblast paracrine signaling to promote osteogenic differentiation of human periodontal ligament cells

doi: 10.3389/fbioe.2026.1753774

Figure Lengend Snippet: Substrate stiffness regulates human gingival fibroblasts (HGFs) behaviors under an inflammatory condition. Real-time RT-PCR was performed to detect gene expression levels of (A) IL4 and IL10 , (B) MMP9 and TIMP1 , and (C) CXCL12 . The expression of GAPDH was used as an internal control. Data were statistically analyzed by one-way ANOVA followed by Tukey’s multiple comparison tests ( n = 3: P < 0.05). (D) The expression protein of CXCL12 was detected by ELISA analysis. Data were statistically analyzed by one-way ANOVA followed by Tukey’s multiple comparison tests ( n = 4: P < 0.05). Data are presented as the mean ± standard deviation (SD), with different letters indicating statistically significant differences between multiple groups. IL4, interleukin 4; IL10, interleukin 10; MMP9, matrix metalloproteinase 9; TIMP1, tissue inhibitor of matrix metalloproteinases 1; CXCL12, CXC motif chemokine 12; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; PDMS, polydimethylsiloxane; LPS, lipopolysaccharide.

Article Snippet: CXCL12 protein in conditioned medium was measured by Human CXCL12/SDF-1α ELISA Kit (Quantikine, R&D systems.

Techniques: Quantitative RT-PCR, Gene Expression, Expressing, Control, Comparison, Enzyme-linked Immunosorbent Assay, Standard Deviation

Journal: Frontiers in Bioengineering and Biotechnology

Article Title: Substrate stiffness modulates human gingival fibroblast paracrine signaling to promote osteogenic differentiation of human periodontal ligament cells

doi: 10.3389/fbioe.2026.1753774

Figure Lengend Snippet: Mitogen-activated protein kinase (MAPK) pathway regulated substrate stiffness-induced CXCL12 expression in human gingival fibroblasts (HGFs). (A) Real-time RT-PCR was performed to detect gene expression levels of CXCL12 . The expression of GAPDH was used as an internal control. Data were statistically analyzed by one-way ANOVA followed by Tukey’s multiple comparison tests ( n = 3: P < 0.05). (B) The protein expression of CXCL12 was detected by ELISA analysis. Data were statistically analyzed by one-way ANOVA followed by Tukey’s multiple comparison tests. ( n = 4: P < 0.05). Data are presented as the mean ± standard deviation (SD), with different letters indicating statistically significant differences between multiple groups. CXCL12, CXC motif chemokine 12; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; PDMS, polydimethylsiloxane.

Article Snippet: CXCL12 protein in conditioned medium was measured by Human CXCL12/SDF-1α ELISA Kit (Quantikine, R&D systems.

Techniques: Expressing, Quantitative RT-PCR, Gene Expression, Control, Comparison, Enzyme-linked Immunosorbent Assay, Standard Deviation

Journal: Frontiers in Bioengineering and Biotechnology

Article Title: Substrate stiffness modulates human gingival fibroblast paracrine signaling to promote osteogenic differentiation of human periodontal ligament cells

doi: 10.3389/fbioe.2026.1753774

Figure Lengend Snippet: Effects of conditioned media of human gingival fibroblasts (HGF-CM) under different substrate stiffness on human periodontal ligament cells’ behaviors. (A) Human periodontal ligament cells (HPDLCs) cultured with HGF-CM in osteogenic medium for 24 h. HPDLCs morphology was demonstrated using a phase-contrast microscope. Scale bars: 300 μm. (B) Real-time RT-PCR was performed to detect gene expression levels of CXCR4 , which is receptor of CXCL12. (C) Real-time RT-PCR was performed to detect gene expression levels of pro-inflammatory cytokine, IL1b . (D) Real-time RT-PCR was performed to detect gene expression levels of MMP8 and TIMP1 . The expression of GAPDH was used as an internal control. (E) Immunofluorescence analysis was performed to detect the protein expression of CXCR4 (green). The cytoskeleton (F-actin; red) and nuclei (blue) were stained using rhodamine-phalloidin and DAPI, respectively. Scale bars: 50 μm. Data were statistically analyzed by one-way ANOVA followed by Tukey’s multiple comparison tests ( n = 3: P < 0.05). Data are presented as the mean ± standard deviation (SD), with different letters indicating statistically significant differences between multiple groups. IL1B, interleukin-1β; MMP8, matrix metalloproteinase 8; TIMP1, tissue inhibitor of matrix metalloproteinases 1; CXCR4, CXC motif receptor type 4; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; PDMS, polydimethylsiloxane.

Article Snippet: CXCL12 protein in conditioned medium was measured by Human CXCL12/SDF-1α ELISA Kit (Quantikine, R&D systems.

Techniques: Cell Culture, Microscopy, Quantitative RT-PCR, Gene Expression, Expressing, Control, Immunofluorescence, Staining, Comparison, Standard Deviation

Journal: Frontiers in Bioengineering and Biotechnology

Article Title: Substrate stiffness modulates human gingival fibroblast paracrine signaling to promote osteogenic differentiation of human periodontal ligament cells

doi: 10.3389/fbioe.2026.1753774

Figure Lengend Snippet: Schematic illustration shows the role of human gingival fibroblast–conditioned media (HGF-CM) in regulating osteogenic differentiation of human periodontal ligament cells (HPDLCs). (A) ECM stiffness stimulates CXCL12 chemokine expression in HGFs, which is associated with enhanced osteogenic responses in HPDLCs. (B) A potential clinical application of this mechanism is the utilization of HGF-derived factors to suppress inflammatory bone resorption and stabilize periodontal tissues. CXCL12: CXC motif chemokine 12.

Article Snippet: CXCL12 protein in conditioned medium was measured by Human CXCL12/SDF-1α ELISA Kit (Quantikine, R&D systems.

Techniques: Expressing, Derivative Assay

Journal: Materials Today Bio

Article Title: Orchestrating the immuno-chondrogenic microenvironment via a bio-inorganic hybrid microsphere system for tendon-to-bone healing

doi: 10.1016/j.mtbio.2026.102851

Figure Lengend Snippet: ZIF-8/sEVs alleviate the inhibitory effects of the M1 M ϕ -mediated inflammatory microenvironment on BMSC migration and chondrogenic differentiation. A) Representative immunofluorescence images of the chemotaxis-associated proteins CXCL12 (green) and CXCR4 (red) in BMSCs cultured under different conditioned media. Nuclei were stained with DAPI (blue). B) Representative optical microscopy images of the scratch wound healing assay at 0 h and 24 h to assess the migratory capacity of BMSCs. C, D) Semi-quantitative analysis of the relative fluorescence intensity of CXCL12 and CXCR4 (C) and the wound healing ratio (D), indicating that ZIF-8/sEVs restore migration inhibited by M1 CM. E–G) Representative immunofluorescence staining of key chondrogenic markers in BMSCs, including (E) Type II Collagen (COL II, red), (F) Aggrecan (red), and (G) Sox-9 (red). The cytoskeleton was stained with Phalloidin (green) and nuclei with DAPI (blue). H–J) Semi-quantitative analysis of the relative fluorescence intensity for (H) COL II, (I) Aggrecan, and (J) Sox-9. M1 CM: M1 M ϕ conditioned media. n = 3. ∗∗p < 0.01, ∗∗∗p < 0.001, ns: p-value with no significance. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)

Article Snippet: Antibodies against HSP70, CD9, CD81, Calnexin, iNOS, CD206, TNF-α, IL-10, CD29, CD90, CD68, CXCL12, CXCR4, COL II, Aggrecan, Sox-9, PI3K, p-PI3K, AKT, p-AKT, and GAPDH were purchased from Abcam (UK), Cell Signaling Technology (USA), Servicebio (Wuhan, China), Abclonal (Wuhan, China), Biolegend (Beijing, China), or Proteintech (Wuhan, China) (detailed information listed in ).

Techniques: Migration, Immunofluorescence, Chemotaxis Assay, Cell Culture, Staining, Microscopy, Wound Healing Assay, Fluorescence