Titanium nanotubes modulate immunophenotyping and cytokine secretion of T cells via IL-17A: a bioinformatic analysis and experimental validation

Object: We aim to explore the immunomodulatory properties of T cells on different titanium nanotubes and the key immunological factors involved in this process.

Methods: Transcriptome data from GEO database of healthy people and healthy implants were used to analyze cell infiltration and factor distribution of adaptive immune using bioinformatics tools. T cells from activated rat were cultured on titanium nanotubes that were prepared by anodization with different diameters (P-0, NT15-30 nm, NT40-100 nm, NT70-200 nm). The proliferation and expressions of the main transcription factors and cytokines of T-cells were detected. Magnetic bead sorting of CD3⁺ T cells and transcriptome sequencing were performed to explore the signaling pathways and key immune factors that may influence the related immune responses.

Results: Bioinformatics analysis showed that healthy peri-implant tissues were enriched by the most of T-cell subtypes. T-cell-mediated adaptive immunological responses involved IL-17A. On the third day, the NT15 and NT40 groups showed significantly higher pro-proliferative effects than the NT70 group (P<0.05). Notably, the NT40 group exhibited the lowest T-bet expression (P<0.05) along with the highest levels of Rorγt, Gata3, and Foxp3(P<0.05), followed by the NT15 group. Additionally, the NT40 group demonstrated reduced RANKL, TNF-α, and IL-6 (P<0.05) and increased OPG and IL-10 (P<0.05). Meanwhile, the NT15 group had lower IFN-γ expression(P>0.05) but higher IL-4, and TGF-β1 expressions(P<0.05). Differential expressed genes (DGEs) of T-cell related to the morphologies of titanium nanotubes were mostly enriched in the IL-17 signaling pathway mediated by IL-17A/F. Gene and protein expressions indicated that the NT40 group had the highest secretion in IL-17A of T cells.

Conclusion: Titanium nanotube morphologies in medium (100 nm) and small (30 nm) sizes significantly influence T cell differentiation and immune factor secretion, with T-cell-derived IL-17A likely playing a key regulatory role.