Three-dimensional reconstructions from non-deparaffinized tissue sections

Three-dimensional (3-D) reconstruction from microscopic images represents a useful tool for the study of biological structures in embryology and developmental biology. However, it is usually necessary to cope with many difficulties connected with the preparation of specimens. In order to minimize mutual displacement of structures in successive sections, the applicability of non-deparaffinized tissue sections for 3-D reconstruction was tested. Chicken embryos were fixed and stained in toto with eosin and then embedded in paraffin. About 30-mum-thick non-deparaffinized serial sections were used for obtaining initial data for 3-D reconstruction of larger stacks of embryonic bodies using either fluorescence or confocal microscope. The same sections served for both collecting optical serial sections of mesonephros as source images for its 3-D reconstruction, and immunohistochemical detection of fibronectin, laminin and vimentin. It was found that sections with retained paraffin preserve the mutual spatial relationships of tissue components as well as provide an excellent differentiation of structure. It makes the process of 3-D reconstruction easier. The localization of the products of immunohistochemical reactions demonstrated the co-localization of fibronectin and laminin in basal laminas and the presence of vimentin in glomeruli and mesenchymal tissue. The use of non-deparaffinized sections represents a less time consuming and more effective alternative to thin histological sections for the purpose of 3-D reconstruction, and enables further application of material.