Presentation of the precision tissue sectioning technique for studying infections and co-infections on complex tissues cultured ex vivo

Abstract

In this paper, we describe a technique that allows getting slices of biological tissues followed by their in vitro culture and infection. Some slices made on pulmonary tissues are presented in order to study the immunologic response to viral respiratory diseases of pigs. This technique of tissue slices’ culture can also be used to study the tissue metabolism or its response to toxic in various organs (1, 2, 3, 4, 5, 6). The lung tissue is complex and infection studies using cell lines do not take into account the tissue architecture and the diversity of its cell component. When studying lung infection or co-infection, it is important to perform a number of replicates, according to the measured traits, for the statistical analysis of results. This technique can be an alternative to in vivo experiments. It conforms to the 3R standards: « reducing » the number of animals, « refining » the experimental protocol, and replacing when possible animal experiments through ex vivo methods. We got a « Tissue slicer » device that allows getting "Precision Cut Lung Slices" (PCLS) representative of the tissue multicellular complexity and that allows studying extracellular interactions in the pulmonary tissue. In these slices the tissue architecture and cell interactions are partially preserved as well as their molecular capacities and functional heterogeneity thus allowing the follow up of the immunological response with a tissue viability of one or two weeks, which allows studying infections and coinfections (7, 8).