ALL YOU NEED TO KNOW ABOUT FFPE

WHAT ARE FFPE

FFPE is a short acronym for Formalin (formaldehyde) Fixed Paraffin Embedded. This is a procedure for preparing tissues for storage and preservation for future use. These tissues will further be used by doctors, researchers, microbiologists among other professionals. FFPE tissue sections are tissues which have been prepared and stored using formalin (formaldehyde) and paraffin. This tissues may be human tissues, rat tissues, mice tissue among many other type of tissues. When this procedure is used, the FFPE tissue sections maintain their morphology and cellular features up to an indefinite duration of time. This enables for study, research and examination of tissues after long periods of time which paves way for more discovery.

STEPS IN TISSUE STORAGE AND PRESERVATION USING FFPE PROCESS

The process of storage utilizes paraffin and formalin which aid in the long-term validity of the tissue specimens. They both have different functions in the preservation of the tissue. Paraffin, for example, makes the tissue slice easier to cut into pieces for mounting on a positively charged glass microscope for viewing. Formaldehyde (formalin) on the other hand preserves vital structures and proteins in the cut tissue sample thus maintaining the valuability for years. Formalin does not activate DNAses and RNAses which in turn degrade the tissues DNA and RNA.

The following are steps used in tissue preservation using the formalin and paraffin

1) A section of human tissue is excised from the body of a donor/ patient. A considerable size is recommended. This is done in presence of a pathologist who is able to determine the best tissue for biopsy and also for noting the current status of the tissue at the time of excision. The tissue can be excised from fetal membranes, human organ, rats or mice.

2) After the excision, the tissue section is placed inside a formaldehyde solution for 48 hours.

3) The formalin fixed tissue is then embedded in paraffin which is IHC grade.

4) The FFPE tissue sections are then stored in hospitals, laboratories, research institutions or tissue banks for future use.

WHAT TO CONSIDER WHEN DETERMINING THE FFPE TISSUE SECTIONS

There are things to consider when choosing FFPE tissue sections. These include - Age of the donor, health condition of the donor, if they had a certain lifestyles i.e smoking or alcohol taking, type of cancer, stage of cancer, the gender of the individual, ethnicity of individual among many other factors. That is why pathologists presence is mandatory when performing an excision.

BENEFITS OF FFPE TISSUE SECTIONS

1) The tissue sections are preserved for future use which enables for study and research.

2)The formalin preserves the morphology, DNA and RNA hence enabling effective storage of tissue.

3) The FFPE allows for storage at room temperature.

4)The FFPE process is cost effective as compared to Frozen tissue since it doesn't need to be in cool temperatures.

5) The Formalin Fixed Paraffin Embedded tissues are beneficial for Immunohistochemistry (IHC).

DISADVANTAGES OF FFPE TISSUE SAMPLES

1.) The components used are toxic i.e formaldehyde and might be hazardous when it comes to handling.

2) Prolonged standing of tissues in formalin affects future molecular studies i.e. Polymerase chain reaction (PCR)

The Uses And Benefits Of Tissue Microarray Slides

Tissue microarray slides contain paraffin blocks. These blocks are up to one thousand different tissues cores. Another important thing to know is that these unique tissue cores are positioned in a beautiful structure. This will help multiplex histological analysis to be possible for users. Do you know that molecular clinical analysis of tissues has some limitations? The truth is that this analysis of tissue comes with restricted patient sample sizes. It also includes restricted visibility of diagnostic reagents and the difficult nature of processes. The strategy behind tissue microarray slides is designed to resolve the issues above.

Process:

A hollow needle is used in the tissue microarray strategy. This needle will help to get rid of tissue cores. The process of removal of the tissue will be as small as 0.6 millimeters in diameter from areas of interest. This is usually paraffin-embedded tissues in the likes of tumor samples or clinical biopsies. In a recipient paraffin block, you can save the tissue cores for more protection. Ensure that when inserting the tissue cores, it should be in a spaced array style. Using a microtome will help you cut out portions of the tissue block. It will later be positioned on a microscope slide and inspected.

The inspection process can be any way of standard historical analysis. It is important to know that every microarray block can be broken into one hundred to five hundred pieces. These broken sections can later be open to other independent tests. In tissue microarray, tests commonly used include fluorescent in situ hybridization and immunohistochemistry. In the analysis of cancer samples, you will discover the uses and benefits of tissue microarray slides. Frozen tissue array is a variation of the process.

Facts:

Tissue microarray remains an innovative exercise. It helps in the relocation or replacement of several tissues sections. This is especially from conventional histologic paraffin blocks. It creates an easy avenue for observing tissues from several samples on the same slide. Tissue microarrays come with a plethora of biomolecules. This can be DNA in their preserved state, RNA, lipids, carbohydrates, and proteins. For a quick analysis of molecular markers, it will provide a high throughput platform.

Even markers linked to physiological, prognosis of diseases or diagnosis conditions, the TMAs will help. For modern molecular pathology, tissue microarrays provide an effective and practical tool with a plethora of benefits. These benefits include a reduction in the number of slides/assay volume, experimental uniformity, and fresh-cut slides. Even for options as compatibility, positive control, and shelf-stability, TMAs will always work.

The Use Of Tissue Microarrays:

Tissue microarray slides can be used along with immunohistochemistry. It has become a better way to validate and research cancer biomarkers in several platforms. It is important to know that a patient’s samples are positioned into the same block. To prevent technical artefacts and experimental variability, portions of the slide can be stained with the same protocol.

Tissue microarray slides and clinical cancer patient cohorts can be used to study prognostic, diagnostic and cure predictive cancer biomarkers. This study can be in several areas, including renal cell, colorectal, breast and lung cancer.