Virtual electron microscopy in cell biology

Virtual microscopy of histological glass slides can emulate conventional light microscopy. Up till now, such a digital simulation does not exist for ultrathin electron microscopic slides. Because of the relative inaccessibility of electron microscopy, evaluation of subcellular structures by (bio)medical students is performed with the aid of photographic prints. In this article, the generation and evaluation of virtual electron microscopic slides is discussed. A T-lymphoblastic cell was used as an example. Electron microscopic pictures were taken at two magnifications (25,000 and 50,000), processed in an analogue or digital way and stitched to reconstruct the image of the total cell. This image is viewed with a webviewer equipped with pan and zoom functions. The possibility of distinguishing the trilaminar structure of cellular membranes was the requisite. Virtual images obtained at an original magnification of 25,000, scanned at a resolution of 800 ppi could compete with pictures developed directly from negatives obtained by electron microscopy. It is possible to navigate and zoom into details in a way emulating electron microscopy. Virtual electron microscopy is innovative and offers new perspectives to interpret cytological pictures and to teach cell biology in an interactive and unique way.