Frozen tissue array consists of fresh frozen tissues in which up to 50 separate tissue cores are assembled in array fashion to allow simultaneous
histological analysis.
History
Paraffin Paraffin may refer to:
Substances
* Paraffin wax, a white or colorless soft solid that is used as a lubricant and for other applications
* Liquid paraffin (drug), a very highly refined mineral oil used in cosmetics and for medical purposes
* Alkan ...
tissue array was developed during late years in the 1980s; this array can help scientists high throughput analyze
gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...
and
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...
expressions in multiple
tissue samples, especially analyze different protein levels with
antibodies by
immunohistochemistry. Various paraffin tissue arrays are now commercially available from many biotech companies. Most of the arrays can be easily made by microarraying instrument (Beecher Instruments Inc.). However, paraffin embedded tissues have limitations. Buffered formalin solutions cross link proteins and nucleic acids when they are used for fix tissues. The DNA, RNA, and protein within the tissues are damaged in various levels during the fixation. Therefore, many scientific experimental results from formalin fixed tissues are not reliable. Since frozen tissue sections don't go through any fixation procedures, and therefore, the DNA, RNA, and protein in frozen tissues retain their native characteristics much more than in paraffin embedded tissues. Scientists who have been developing antibodies for therapeutic purpose all need their preliminary results from frozen tissues to get approval from FDA. Consequently, frozen tissue array should be the best tool for high throughput analysis on this purpose.
Procedure
Frozen tissue cores with 2 mm diameter from the regions of interest are removed from frozen tissue OCT blocks at different freezing temperature since each tissue type has their own temperature preference at frozen stage. Then all the frozen tissue cores are inserted in a recipient OCT frozen block in a precisely spaced, array pattern. Sections from this block are cut using a cryostat, mounted on a microscope slide and then analyzed by any method of standard histological analysis. Each frozen tissue array block can be cut into 100–500 sections, which can be subjected to independent tests. Tests commonly employed in frozen tissue array include immunohistochemistry, and in situ hybridization.
See also
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Cytomics
Cytomics is the study of cell biology (cytology) and biochemistry in cellular systems at the single cell level. It combines all the bioinformatic knowledge to attempt to understand the molecular architecture and functionality of the cell system (C ...
*
Frozen section procedure
The frozen section procedure is a pathological laboratory procedure to perform rapid microscopic analysis of a specimen. It is used most often in oncological surgery. The technical name for this procedure is cryosection. The microtome device that ...
*
MicroArray and Gene Expression (MAGE)
References
* Battifora H: The multitumor (sausage) tissue block: novel method for immunohistochemical antibody testing. Lab Invest 1986, 55:244-248.
* Battifora H, Mehta P: The checkerboard tissue block. An improved multitissue control block. Lab Invest 1990, 63:722-724.
* Kononen J, Bubendorf L, Kallioniemi A, Barlund M, Schraml P, Leighton S, Torhorst J, Mihatsch MJ, Sauter G, Kallioniemi OP: Tissue microarrays for high-throughput molecular profiling of tumor specimens. Nat Med 1998, 4:844-847.
*Schoenberg Fejzo M, Slamon DJ: Frozen tumor tissue microarray technology for analysis of tumor RNA, DNA, and proteins. American Journal of Pathology 2001, 159(5): 1645–50.
* Schoenberg Fejzo M, Slamon DJ. Tissue microarrays from frozen tissues-OCT technique. Methods Mol Biol. 2010, 664:73-80.
*
Frozen Tissue Array. ''BioChain Institute Inc''. Retrieved 2017-06-24.
Tissues (biology)
Microarrays