Preparation and maintenance of organotypic slice cultures of CNS tissue

Organotypic slice cultures are the in vitro method of choice for applications requiring long-term survival of the preparation and a high degree of cellular differentiation and organization resembling that of the original tissue. Long-term survival is achieved by culturing slices at the air/liquid interface, either by continuously rotating the preparation (roller-tube cultures) or by culturing them on semiporous membranes (stationary interface cultures). Both culture techniques yield nerve cells which are highly differentiated in terms of their morphological and physiological characteristics. Because most of these cultures are prepared from 1-week-old postnatal animals, in which the cellular and tissue organization is already relatively advanced, the original cytoarchitecture is often remarkably well maintained. Moreover, the presence of a full complement of glial and nerve cells is thought to provide a microenvironment facilitating differentiation of neurons. Slice culture also offers unique advantages for recording from pairs of cells, as a consequence of the high degree of connectivity between nerve cells. Recently, new applications have emerged such as the cultivation of slices from knock-out animals with limited postnatal survival time or alteration of gene expression by viral vectors.