Biologists working tirelessly often find themselves in sticky situations as biology is often plagued with the situation that takes the form of validating a new idea on live human tissue. It comes from the fact that there is never enough live human tissue to begin with – be it in case number or amount so that the research work can be carried out seamlessly.
The research world is plagued with the above mentioned problem as most of the time the tissue is prepared by a pathologist who is given the primary aim of sampling the tissue obtained and provide help to a health practitioner while they deliver diagnostic consultation to their patient. Obviously, in such a situation, the pathologist won’t take the necessary steps to make sure that the sample is intact enough to be used for future research work.
The situation takes a turn for the worse when one takes a look at some stringent guidelines when it comes to getting all the necessary consent from apex bodies about the extraction of information from tissue samples. All one can do is to make sure that they are taking all the necessary steps there is so that the sample is optimally managed to keep the genetic information within intact – thus increasing its value.
Cue in TMA or Tissue Microarray which is the go-to process of making the best use of hard-to-get-a-hold-of resources like human tissue samples for research work. Before going further with all the technicalities, let us get down to what is tissue microarray?
TMA – Tissue Microarray
TMA or Tissue Microarray is considered one of the most popular methods used in genetic research that finds extensive use in comprehensive gene expression. It is also helpful when a researcher is trying to get as much information as they can from a single tissue sample or from a single antigen and look at the way how it expresses itself across several cells and tissues at a single go.
The tissue samples need to be specially prepared when one wants to analyze the same using TMA. The tissue samples are collected from paraffin-embedded blocks using specially designed hollow needles and transferred to new recipient paraffin blocks, arranged in a uniformly spread array pattern. The recipient paraffin blocks are then further cut using a specially designed tool called a microtome. These cut sections are then loaded on to a glass slide and placed under the microscope for further analysis.
Uses of TMA
TMA finds extensive use in the following:
- Staining – Similar to the run-of-the-mill paraffin embedded or formalin fixed tissue samples, TMA is compatible with a range of analytical techniques such as in situ hybridization, fluorescent visualization, immunologic stains, histochemical stains, etc.
- Tissue Retention – TMA is an effective process that is ideal if the researcher plans on coring the paraffin blocks several times without destroying the same. Even if the tissue block has been cored several times, with precision sectioning, it is possible to make a correct diagnosis even from samples that have been prepared for other studies.
It is clear from the above sections that TMA is an important part of genetic research. It is why TMA also finds extensive use in the conservation of tissue samples. Conservation of tissue samples is crucial for research work for diseases that are still without a proper cure – such as cancer.