First-time users are encouraged to contact us to discuss their experiments for advice on tissue collection, fixation, embedding, and stains. Add any instructions to the submission form special request section and it is advisable to discuss your needs at the time of sample submission.
Supplies (*free to MPC users)
- *10% neutral buffered formalin in 8 oz. specimen cups (NBF, ThermoFisher, 23-032-060)
- *Specimen containers (recycled, all sizes)
- *Slide boxes (recycled, all sizes)
- *Cassettes (biopsy and regular sizes)
- *Biopsy sponges and bags
- Mega-cassettes and SupraMega cassettes available for purchase
- Paraffin slides- trim, process, embed, section, stain, microscopy, analyze
- Frozen slides- sucrose cryoprotection for fixed frozens, embedding for fresh or fixed frozen blocks, section, stain, microscopy, analyze
- DNAse/RNAse free slide sectioning
- H&E and Special stains: PAS/PASD, Oil red O (frozen only), Congo Red, Masson’s Trichrome, and many others.
- Vibratome sectioning- thick sections of living or fixed tissues embedded in 2-3% low melt agarose immediately prior to sectioning. The Compresstome vibratome can be rented by trained users.
Paraffin processing is performed using automatic processors (VIP6, Leica) with graded ethanols (70-100%) and xylene. Fixation is performed and ended in one’s lab then samples are submitted in PBS or ethanol. Standard processing programs are based on species, tissue, and fat content. Customized programs can be set up to your specifications.
Several different levels of sectioning are available for paraffin and frozen tissues (adapted from Gladstone Histology Core, UCSF):
- Sections- block is trimmed to full face and 1 unstained section is placed on a slide. Multiple sections can be put onto a slide depending on tissue size. The total number of slides needed depends on what you need ie H&E, IHC, or only unstained slides. Paraffin samples are routinely sectioned at 4 um thickness unless another thickness is requested.
- Serial sections on the same slide– serial sections in ribbons of paraffin or from adjacent frozen sections are placed on the same slide. Each section is immediately adjacent to the last one. This technique is good for surveying a special area of interest.
- Serials across adjacent slides – adjacent sections are placed on separate slides across a set with each slide in the set is then representative of the whole area of interest. This is ideal when you want to perform multiple probes/antibodies/downstream techniques on the same sample, in series, so each section needs to be on its own slide.
- Levels – unstained section is placed on a slide, then a certain distance (um) is discarded and then another section is placed on a slide- this distance is referred to as a level. Indicate the level distance on the submission form. Levels are often requested when a large amount of tissue is to be surveyed and every section doesn’t need to be kept. You must request additional slides and/or additional sections at a level as once a level is cut through, there is no retrieving that tissue.
- Special sectioning to view a particular area of interest, e.g. islet transplant, lesion found at necropsy, hippocampus in coronal or sagittal brain sections. These requests require orienting and trimming the tissue before placing it in the cassette. Sections are placed either serially on the same slide or on different slides.
Personalized services are available such as working with a histotechnician to identify structures of special interest while the tissue is being sectioned or for developing a new procedure.