Three-Dimensional Bioprinting of Tarsal Plates with Adipose-Derived Mesenchymal Stem Cells: Evaluation of Meibomian Gland Reconstruction in a Rat Model

Background: The aim of this study was to develop 3D-bioprinted scaffolds embedded with human adipose-derived stem cells (hADSCs) to reconstruct the tarsal plate in a rat model. Methods: Scaffolds were printed using a 3D bioprinter with a bioink composed of atelocollagen and alginate. hADSCs (5 × 10⁵ cells/mL) were embedded within the bioink. A total of 30 male Sprague Dawley (SD) rats (300 g) were divided into three groups: group 1 (normal control, n = 10), group 2 (3D-bioprinted scaffolds, n = 10), and group 3 (3D-bioprinted scaffolds with hADSCs, n = 10). Four weeks after surgery, a histopathological analysis was performed using hematoxylin and eosin (H&E) staining, Masson's trichrome (MT) staining, and immunofluorescence staining. Gene expression of SREBP-1, PPAR-γ, FADS-2, and FAS was assessed via real-time polymerase chain reaction (PCR). Results: No abnormalities were observed in the operated eyelids of any of the 30 rats. The histopathological analysis revealed lipid-secreting cells resembling meibocytes in both group 2 and group 3, with more pronounced meibocyte-like cells in group 3. Immunofluorescence staining for phalloidin expression showed a significant increase in group 3. Additionally, the RNA expression of SREBP-1, PPAR-γ, FADS-2, and FAS, all related to lipid metabolism, was elevated in group 3. Conclusions: The 3D-printed scaffolds combined with hADSCs were effective for tarsal plate reconstruction, with the hADSCs notably contributing to the generation of cells associated with lipid metabolism.