Basal lamina formation by porcine thyroid cells grown in collagen- and laminin-deficient medium

Abstract

Porcine thyroid cells isolated by dispase treatment were cultured in either (a) Matrigel, (b) agarose with the addition of different combinations of basic fibroblast growth factor and laminin, or (c) on agarose-coated dishes. The formation of follicles and the presence of a basal lamina was investigated by routine electron microscopy of Araldite-embedded material and by light and electron microscopical immunocytochemical detection of the basal lamina components, laminin and collagen type IV. After 10 days of culture in Matrigel or agarose, a basal lamina-like structure surrounded most follicles. Follicles of cells growing in agarose and overlaid with a medium containing thyrotropin and overlaid with a medium containing thyrotropin and fibroblast growth factor showed a fluorescent band at the basal side of the follicles after immunocytochemical staining with anti-laminin and anti-collagen antibodies. Routine electron microscopy showed that a basal lamina-like structure lined the outside of the follicle. This structure could be subdivided into a lamina lucida and a lamina densa. Electron microscopical immunogold labelling revealed that immunologically detectable laminin was confined to the lamina densa. These findings suggest that even in the absence of basal lamina components in the culture medium, thyroid cells are able to form follicles with a regular basal lamina when they are cultured in a three-dimensional environment.

Thyrocyte integration, and thyroid folliculogenesis and tissue regeneration: Perspective for thyroid tissue engineering

“… 7,13,14 Such basement‐membrane organization appears to actively maintain thyroid‐follicle structures through stability of thyrocyte integration. Matrigel (Collaborative Research, Bedford, MA, USA) can also be applied in 3‐D gel culture, 41–45 although its strength is weaker than that of type I collagen gel. Type I collagen can be mixed with various ECM molecules or cytokines in a 3‐D culture system (unpublished data).…”

Fabrication of Functional Cell Sheets with Human Thyrocytes from Non-Tumorous Thyroid Tissue

“…Bechtner et al [10] cultured isolated porcine thyroid follicles in Matrigel, thereby providing a tool for investigating the regulation of follicular growth and neoformation close to the in vivo situation. Fröhlich et al [11] showed that porcine thyroid cells were able to form follicles with a regular basal lamina when they were cultured in a 3D environment. Takasu et al [12] analyzed the relationships of iodine metabolism and cell polarity, using polarized monolayer porcine thyroid cells cultured on collagencoated filters and double layered, follicle-forming cells.…”