Heat stabilization

Heat stabilization is an additive-free preservation technology for tissue samples which stops degradation and changes immediately and permanently. Heat stabilization uses rapid conductive heating, under controlled pressure, to generate a fast, homogenous and irreversible thermal denaturation of proteins, resulting in a complete and permanent elimination of all enzymatic activity that would otherwise cause further biological changes to the tissue sample ex vivo. Due to the permanent inactivation of enzymes, heat stabilization overcomes the drawbacks of conventional tissue sample preservation techniques, such as snap-freezing followed by inhibitors.^[1]

Understanding the role of proteins, peptides and small molecules in normal and diseased tissue is crucial to defining their potential use as drugs, drug targets or disease biomarkers. Yet biological changes begin the moment tissue is removed from its native environment. Dramatic alterations at the molecular level occur within seconds e.g. changed metabolism, catabolic fragmentation of large molecules (such as ATP) occurs in order to release energy, leading to disrupted control mechanisms, phosphorylation states are altered and proteins begin to degrade. As a consequence vital information may be lost or distorted, leading to inter-sample variation, risk of incorrect data interpretation and potentially misleading conclusions.^[2]

Heat stabilization offers significant advantages over conventional approaches to preventing biological change.^[3] It can be used to replace snap freezing followed by inhibitors, pH changes, organic solvents or cross-linking. It can also be used with frozen tissue, allowing stabilization of stored samples. Heat stabilization can be used for almost any kind of tissue sample, and has been verified to be compatible with many downstream analytical techniques such as mass spectrometry,^[4] phospho-shotgun,^[5] MALDI imaging,^[6] Western blot,^[7] 1D and 2D gels, reversed-phased protein arrays,^[8] RIA and ELISA. The method also allows samples collected and handled in bio safety level laboratories to be subsequently handled outside such labs after treatment.^[9]

References

1. Svensson M, et al. (February 2009). "Heat Stabilization of the Tissue Proteome: A New Technology for Improved Proteomics". J. Proteome Res. 8 (2): 974–981. doi:10.1021/pr8006446. PMID 19159280. (subscription required (help)).
2. Sköld K, Alm H, Scholz B (June 2013). "The impact of biosampling procedures on molecular data interpretation". Mol. Cell. Proteomics (Review). 12 (6): 1489–1501. doi:10.1074/mcp.R112.024869. PMID 23382104.
3. Söderquist M (15 January 2013). "Eliminating biological change after excision". Gen. Eng. Biotechnol. News (Tutorial). 33 (2).
4. Smejkal GB, et al. (August 2011). "Thermal stabilization of tissues and the preservation of protein phosphorylation states for two-dimensional gel electrophoresis". Electrophoresis. 32 (16): 2206–2215. doi:10.1002/elps.201100170. PMID 21792998. (subscription required (help)).
5. Lundby A, et al. (June 2012). "Quantitative maps of protein phosphorylation sites across 14 different rat organs and tissues". Nat. Comm. 3 (876). doi:10.1038/ncomms1871. PMID 22673903.
6. Blatherwick EQ, et al. (July 2013). "Localisation of adenine nucleotides in heat-stabilised mouse brains using ion mobility enabled MALDI Imaging". Int. J. Mass Spectrom. 345–347: 19–27. doi:10.1016/j.ijms.2013.02.004. (subscription required (help)).
7. Spellman C, et al. (January 2013). "Expression of trisomic proteins in Down syndrome model systems". Gene. 512 (2): 219–225. doi:10.1016/j.gene.2012.10.051. PMID 23103828.
8. Ahmed MM, et al. (May 2013). "Protein profiles in Tc1 mice implicate novel pathway perturbations in the Down syndrome brain". Hum. Mol. Gen. 22 (9): 1709–1724. doi:10.1093/hmg/ddt017. PMID 23349361.
9. "CDC Invests in Denator's Heat Stabilization Technology". News: Products & Services. Gen. Eng. Biotechnol. News (Paper). 36 (14): 8. August 2016.