From cells to tissues: fluorescence confocal microscopy in the study of histological samples

Our knowledge of the genetic mechanisms controlling cell proliferation and differentiation usually originates from in vitro cultured cell line models. However, the definition of the molecular switches involved in control of homeostasis and the understanding of the changes occurring in neoplastic transformation require looking at single cells as the components of a complex tissue network. Histological examination of tissue samples can gain a substantial amount of information from high-resolution fluorescence analysis. In particular, confocal microscopy can help in the definition of functional pathways using multiparameter analysis. In this report, we present acquisition and analysis procedures to obtain high-resolution data from tissue sections. Confocal microscopy coupled to computational restoration, statistical evaluation of spatial correlations, and morphological analysis over large tissue areas were applied to colorectal samples providing a molecular fingerprint of the biological differences inferred from classical histological examination.