Tissue cassette

In essence, the basic steps of making cell blocks consist of fixation, centrifugation to make cell pellet, transfer the pellet to a labeled tissue cassette which then is processed and embedded in paraffin. The most challenging component of this technique is the methods to harden the cell pellet so it can be easily picked up from the tube without losing precious material. With only a simple sedimentation technique, the cell pellet is usually small and friable. In order to harden the cell pellet, several technical modifications have been reported. The most popular methodology includes plasma-thrombin clot technique, agar technique, and fixation with Bouin s solution. 

Place the processing cassette with the tissue in 70% alcohol into the tissue processor for dehydration and infiltration with paraffin (see Note 4). 

Embed tissue samples in paraffin wax in embedding cassettes. 

Plastic histology tissue processing cassettes for individual rodent fetuses. 

Transfer mouse hind paws to labeled tissue embedding and processing cassettes. 

BCRP is classified in ABCG subfamily other members of this subfamily are involved in sterol transport (269). Unlike P-gp and MRPs, BCRP consists of a single ABC cassette in the amino terminal followed by six putative transmembrane domains however, it forms a homodimer linked by a disulfide bond in the plasma membrane (270,271). Initially, ABCG2 was identified as an mRNA expressed in placenta (272) and as a non-MDRl- and non-MRP-type resistance factor from cell lines selected in the presence of anthracy-clines and mitoxantrone (273). BCRP is expressed widely in the normal tissues (274) and localized on the canalicular membrane of the hepatocytes and apical membranes of epithelial cells (274,275) and brain capillary endothelial cells (276,277). 

With the case number assigned, the requisition form and specimen containers correctly labeled and tissue cassettes printed, it s time for the grossing of the specimen. 

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