Preparation of cryosections from frozen porcine pulmonary tissue for MALDI mass spectrometry imaging

Abstract

In last decades, a matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) was used for mapping the spatial distribution of different molecules, mainly peptides, proteins, lipids and metabolites, in different types of tissue. Cryosections are the best suited for getting as much information as possible because the preparation of samples for MALDI MSI does not include deparaffinization and antigen-retrieval steps which are needed in case of conventional formalin-fixed and paraffin-embedded (FFPE) tissue sections. To analyse infection markers like interleukins in the tissue sections of porcine lungs affected by Actinobacillus pleuropneumoniae, it was necessary to obtain very well prepared cryosections for MALDI MSI. Therefore, this work was focused on optimization of preparation of frozen porcine lungs and its cryosections with conserved morphological structure.