Buying FFPE Blocks
What is FFPE Tissue?
FFPE tissue or formalin fixed paraffin embedded tissue is a type of tissue specimen. Like all human tissue procurement it has been used by the researchers and the medical community alike for the study of disease progress, treatment, prognosis, and more. As its name suggests, the tissue samples are preserved using formaldehyde and embedded into paraffin wax in order to preserve the protein and structures in the specimen. Once preserved in blocks, slices of the block are made and mounted onto a slide to be examined under a microscope.
FFPE tissue blocks have a great advantage over other tissue blocks as properly prepared blocks and slides can be stored for a long time making it easy to use for retrospective research and clinical studies. Quality FFPE specimens are important as they can affect the results and outcome of specific research. FFPE tissues are used in therapeutic areas such as oncology, hematology, immunology or control. Its use can also be found in procedures such as tissue microarrays that are constructed from FFPE blocks. FFPE samples are a great asset to the medical field and to research studies as it is easy and inexpensive to store, it also preserves the integrity of samples for a long time.
Biobanks and Biorepositories
Biobanks and biorepositories gather, process, and store tissue specimens and its associated data that can then be used for research and clinical studies. There are huge numbers of FFPE blocks that are stored worldwide. These tissues are well-preserved tissues and can provide clinical and demographic data. The data gathered by these biorepositories provide crucial information from participant phenotype to genetics and proteomics. Good quality specimens are needed in the advancement of molecular studies and development of targeted therapies. FFPE samples are important as more samples would enable researchers to identify rare variants of diseases.
Purchasing FFPE Samples
FFPE tissue samples have certain limitations as researchers have difficulty extracting usable DNA, RNA, and protein material. This is because the formalin used in the preservation of tissues cross-links nucleic acids. There is also no standard procedure or protocol used in the collection and fixation of tissues. This can result in a wide variation in the quality of tissue samples due to differences in handling, fixation, and embedding of specimens. Finding high-quality FFPE samples can be challenging. To purchase reliable samples, try looking for samples that have the proper regulatory and clinical documentation. Some other factors to look out for include:
a) Quality Control
The FFPE sample should be subjected to quality control once received by the tissue bank. The FFPE blocks are then reviewed both grossly and microscopically to verify that the samples meet the proper criteria. This ensures that buyers and research teams are able to obtain valuable information from the specimen.
b) Licensed Pathologist
The integrity of specimens can be affected by factors during collection (surgery), such as the administration of anesthesia, ligation of vessels, and the removal of a specimen from the body. Once the specimen is removed from the body, degradation begins and limits the value of the specimen for research. A licensed pathologist should thus be available to ensure that the collection is performed properly. The time that each specimen is collected should also be recorded. Samples are then evaluated to ensure they are acceptable specimens.
Before purchasing any specimens, the availability of information is also important (such as genetic profile data). Genetic profile information makes the sample important for research that focuses on drug targets. This information is important as it can dramatically shorten work times for staff and provide quicker results. Look for samples that include demographic details, pathology report, staging of the disease, and treatment status if available.
As previously mentioned, since the process of fixation can vary for FFPE samples as there is no set protocol. Therefore, it is important that buyers should have access to the information of the fixation process such as formalin composition, the thickness of tissue sample, and the duration of fixation.
e) Capabilities of the Laboratory
Not all tissue banks have the same range of lab capabilities or level of scientific expertise. Before purchasing samples, try asking for more information regarding their workflow and protocols used during processing of samples. Ask to speak to someone who specializes in the procurement of the specimen.
FFPE tissue samples are important for many ongoing studies as it provides crucial information. It is a vital source for many large-scale types of research. Finding a trusted supplier for your tissue samples is crucial as it affects the results and outcome of your research. Using high-quality FFPE samples can help your research to move forward and provide better results.
Doiron L. 6 FFPE samples purchasing tips. Folio Conversant. Accessed 6/5/2018. http://www.conversantbio.com/blog/bid/337548/6-FFPE-Samples-Purchasing-Tips