Simultaneous preservation of biomolecules, such as nucleic acids and proteins, and morphology features of a tissue sample is challenging. Snap-freezing in liquid nitrogen (N2) is the preferred method for biomolecule preservation, but the procedure damages tissue morphology. Furthermore, sectioning unfixed, frozen samples is technically demanding and requires specialized equipment. Formalin has been used for decades to preserve tissue mophology, but formalin crosslinks proteins and nucleic acids, making extraction of high-quality biomarkers from formalin-fixed, paraffin-embedded (FFPE) tissue difficult or impossible.
The PAXgene Tissue System is a formalin-free solutions for the simultaneous preservation of morphology and biomolecules and the purification of high-quality RNA, DNA, microRNA (miRNA), proteins and phosphoproteins from the same sample. Tissue specimens are collected, fixed and stabilized with the PAXgene Tissue System. PAXgene Tissue-fixed tissue can be processed and embedded in paraffin similarly to formalin-fixed tissue, and biomolecules are extracted using the companion kits: the PAXgene Tissue DNA Kit for the purification of DNA or the PAXgene Tissue RNA/miRNA Kit for purification of total RNA, including miRNA. Additionally, supplementary protocols are available for purification of full-length proteins from PAXgene Tissue-fixed, paraffin-embedded tissue with the Qproteome FFPE Tissue Kit.
Simultaneous preservation of tissue morphology and biomolecules. The same sample can be used for standard histomorphological analysis and molecular analyses of nucleic acids and proteins.
Unique crosslinking-free stabilization of molecular content. Unlike conventional fixation methods, the PAXgene Tissue System uses reagents that quickly perserve tissue morphology and stabilize biomolecules without crosslinking or other chemical alterations.
Rapid and convenient tissue fixation. Tissue samples are fixed at room temperature (15–25°C) in as little as 2 hours (depending on tissue type and size) and can be embedded and processed in paraffin.
Convenient tissue storage and transportation. Tissue remains stable for up to 7 days at room temperature (15–25°C) or up to 4 weeks at 2–8°C.* Longer storage can be done at –20°C or –80°C without negative effects on the morphology of the tissue or the integrity of its nucleic acids.
Multimodal analysis of samples. PAXgene Tissue-fixed (PF) samples as well as PAXgene Tissue-fixed, paraffin-embedded (PFPE) tissue samples are suitable for tissue pathology evaluations based on multiple analyses, including histochemical staining, immunohistochemistry, in situ hybridization, gene expression analysis, genetic analysis, sequencing, protein and phosphoprotein analysis.
* Storage at 2–8°C for more than 4 weeks must be validated for each tissue type.