Diagram of ArrayPlate assay. Proprietary lysis buffer (HTG) is used to lyse and permeabilize FFPET tissue sections. Specific nuclease protection probes are added, which hybridize to all mRNA, either soluble or still cross-linked. S1 nuclease is added to remove nonspecific RNA, leaving only target mRNA/probe duplexes. The hybridized-specific probes are released by hydrolysis and the isolated probes are transferred to an ArrayPlate well for detection using linkers, detection probes, and a chemiluminescent substrate. The method enables expression profiling of multiple mRNAs without RNA extraction by the use of short probes capable of hybridisation to both soluble and insoluble/cross-linked mRNA of importance in FFPET. Adapted by permission from Macmillan Publishers. Roberts RA, Sabalos CM, LeBlanc ML, et al. Quantitative nuclease protection assay in paraffin-embedded tissue replicates prognostic microarray gene expression in diffuse large-B-cell lymphoma. Lab Invest. 2007;87:979-997.