Viscoelastic Janus Nanocomposite Hydrogel for Periodontitis Immunomodulation via Co-delivery of IL- 1β Monoclonal Antibody and PDLSC Exosomes

A viscoelastic Janus nanocomposite hydrogel (Janus-GelLap) was engineered via sequential 3D printing using Gelatin Methacryloyl (GelMA) and exfoliated Laponite nanosilicates to enable spatiotemporally controlled co-delivery of a neutralizing IL-1β monoclonal antibody with documented cross-reactivity to rodent IL-1β (aIL1β) and periodontal ligament stem cell-derived exosomes (PDLSC-Exos). The fully exfoliated Laponite network increased the hydrogel’s surface area from 4.85 to 25.84 m²/g and enhanced the storage modulus (G′) from 2.15 to 8.24 kPa, endowing excellent shear-thinning and >95% rapid self-healing. In vitro release studies showed a biphasic diffusion of aIL1β (22 ± 3% burst, 78 ± 4% total) and a sustained zero-order-like release of PDLSC-Exos (61 ± 5% total) over 14 days, governed by Fickian (n = 0.48) and non-Fickian (n = 0.78) mechanisms, respectively. Cytocompatibility tests confirmed >95% cell viability with a 1.3-fold increase in hPDLSC proliferation. In LPS-stimulated macrophages, Janus-GelLap reduced TNF-α and iNOS expression by >80% while elevating Arg-1 and IL-10 by ≈5-fold; ELISA revealed TNF-α = 410 ± 65 pg/mL and IL-10 = 615 ± 80 pg/mL, confirming synergistic M1 suppression and M2 activation. In a rat periodontitis model, micro-CT analysis demonstrated near-complete bone preservation (CEJ–ABC = 0.51 ± 0.06 mm; BV/TV = 68.1 ± 4.6%; BMD = 1.10 ± 0.10 g/cm³; Tb.Th = 85 ± 6 μm), statistically indistinguishable from healthy controls. Although comprehensive periodontal immune cell profiling by flow cytometry and expanded leukocyte panels was not performed, immunofluorescence/immunohistochemistry of the defect region provided direct in vivo evidence of immunomodulation, revealing a pronounced shift in macrophage polarization from F4/80⁺iNOS⁺ M1 to F4/80⁺CD206⁺/Arg-1⁺ M2 phenotypes, accompanied by reduced IL-1β/TNF-α and enhanced OCN/Runx2 expression. These findings establish the Janus-GelLap as a multifunctional immuno-regenerative platform that effectively halts inflammation-driven alveolar bone loss and promotes coordinated tissue regeneration, providing a clinically translatable paradigm for osteoimmunomodulatory therapy in chronic inflammatory diseases such as periodontitis.