I will be starting a lab with tissue microarray capabilities. Does anyone have any recommendations for systems/set-up equipment that is user-friendly? In terms of imaging and quantification, I am thinking of going with an Aperio system.
I am not familiar with apparatus, but it is very important to standardize tissue processing and staining. E.g. fixation time, use the same fixative for all tissues. Take care that enough tissue is available around to punch site. If you apply immunohistochemistry or in situ hybridization perform model experiments at first to make an inventarization of the staining intensity in different tissues.
Be aware that for routine processing more or less yes/no answers, or at least at a 4 point scale can be scored, unless you use integral density/colour measurements. The critical point when you score densities is the requisite of a homogeneous staining all over the tissue array.
In terms of cell imaging, Aperio system and software is good, as well as the free open-source ImageJ program. You are advised to have a high quality microscope, Olympus, Polyvar (Righert-Jung), Leica or similar brands equipped with high resolution digital cameras.
For tissue sectioning, I may recommend the manual-electrical microtome for paraffin embedded tissues, and the open stage-and-knife freezing microtome (that does not need to freeze your sample with liquid nitrogen) or the closed cabinet cryostat apparatus for preparing the fresh frozen sections. The Richert-Jung brand is an efficient and durable one.
We did a lot of TMA in NZ - got some made by a corer instrument in Queensland but these were not very satisfactory as the block did not adhere to the cores well and many curled on sectioning we eventually settled on a manual kit http://www.ihcworld.com/products/Quick-Ray.htm
The important thing about this is the premade blocks which melt at 60 C and bind the cores - you can use the coring machine or you can also use a standard 2mm biopsy punch. The important thing is that the blocks has been sectioned parallel to the holder and still have plenty of depth - should be able to get about 2 mm of core. the number of cuts is determined by the shallowest core.
the automatic machine requires that you identify areas to core on a H&E but the H&E expands somewhat when floated on the water bath so the spots do not correspond exactly with the core. It is better to get the pathologist to hand mark the block and hand core if you want fine structures such as the invasive front of the tumour etc.
These were paraffin blocks cut on a leica microtome.
We used a Nikon Research Grade epifluorescent microscope with a 4.3 meg camera and Image Pro for image analysis. Good luck with the work.
Our lab has been using Tissue microarrays for several years. We still use the manual staining for the arrays and a Pascal pressure cooker for antigen retrieval.
We have 2 Beecher semiautomatic arrayers that have stood the test of time. Spare parts are not much of a problem. They are easy to use and maintain. We do have a manual arrayer that is used very rarely, to punch parafin blocks.
The automated Beecher ATA27 we purchased had problems with needles breaking very frequently, and hence is not preferred by the tecs.
Having a Pathologist map out slides using different color for tumor, adenoma or normal areas improves the overall reliability and standard of the TMA.
We use the Microm HM360 to cut the TMA blocks. All other FFPE blocks are cut on a Leitz 1512 microtome.
Once you have standardized your parafin and other materials in-house, I am sure you will be confident in no time.
Contact Professor Dave Burger at the University of Pretoria - South Africa he has a great lab -
Aperio system is appropriate. Yuo may need to set up a separate formalin fixed tissue bank other than archival diagnostic paraffin blocks. you can obtain them from what left over from surgical specimen after complete sign out of case.. So you can have plenty of tissue to optimize the array
- Badges
- Science topic