技术资料

Expansion microscopy (ExM) has enabled nanoscale imaging of tissues by physically enlarging biological samples in a swellable hydrogel. However,the increased sample size and water-based environment pose challenges for deep imaging using conventional inverted confocal microscopes,particularly due to the limited working distance of high-numerical-aperture (NA) water immersion objectives. Here,we introduce a practical imaging alternative that utilizes an inverted water-dipping objective and a refractive-index-matched optical path using fluorinated ethylene propylene (FEP) film. Through point spread function (PSF) measurements and simulations,we show that the FEP film introduces predominantly defocus-like wavefront profiles characteristic of high NA systems,which result in an easily correctable axial shift of the focal plane. To ensure stable immersion and refractive index continuity,we use an arrangement relying on an FEP film,Immersol W,water and a FEP-based imaging dish. This configuration achieves sub-micron lateral and axial resolution,supports large tile-scan acquisitions,and maintains image quality across depths exceeding 800 µm. We validate the system by imaging 4×-expanded U2OS cells and human cerebral organoids. Our approach provides a low-cost,plug-and-play solution for high-resolution volumetric imaging of expanded samples using standard inverted microscopes. View Publication

Interleukin-17 (IL-17) plays a central role in the pathogenesis of various autoimmune diseases. Soluble CD14 (sCD14),a marker of innate immune activation,is elevated in several inflammatory conditions. However,its influence on IL-17 production and the differentiation of Th17 cells remains poorly understood. We found that sCD14 enhances Th17-associated cytokine production and up-regulates critical transcription factors such as STAT3 and RORC. Notably,sCD14's effect on Th17 polarization was mediated indirectly through autologous sCD14-treated peripheral blood mononuclear cell (PBMC) supernatant (sCD14-PBMC-Sup). Additionally,we identified a distinct cytokine profile enriched for pro-inflammatory cytokines and chemokines in sCD14-treated T cells,further reinforcing the Th17-promoting role of sCD14. Interestingly,gamma-aminobutyric acid (GABA),a metabolite elevated in sCD14-treated monocytes,was identified as a potential contributor to Th17 polarization. GABA supplementation in T-cell cultures enhanced IL-17A secretion,indicating its role as a signaling molecule in T-cell differentiation. Our findings also revealed the expansion of innate lymphoid cell (ILC)2/3-like cells in T-cell cultures exposed to sCD14-PBMC-Sup and GABA,highlighting the potential role of monocytes in Th17-mediated immunity. Furthermore,while sCD14 promoted Th17 polarization,it simultaneously impaired T-cell activation and proliferation,suggesting an immunosuppressive effect mediated by soluble factors released from monocytes. These results underscore the dual role of sCD14 in modulating T-cell responses,promoting Th17 differentiation while suppressing T-cell effector functions. This study identifies a previously unrecognized role for sCD14 in promoting Th17 induction,highlighting its contribution to immune regulation and its potential as a therapeutic target in Th17-driven autoimmune conditions. View Publication