Mounting Paraffin Sections onto Slides

Prior to immunohistochemical staining, paraffin sections must be properly mounted onto slides, and then deparaffinized and rehydrated. To help adherence to the glass and decrease the chances of sections dissociating from the slides, paraffin tissue sections should be mounted on tissue-adhesive-coated slides. The use of tissue-adhesive-coated slides is especially important for paraffin tissue sections undergoing heat-induced antigen retrieval (see Sect. 6.1.1). 

As for paraffin sections, it is advisable to mount cryosections also onto adhesive-coated slides in order to decrease the chances of sections dissociating from the slides in the course of immunohistochemical staining. Once mounted on slides, cryosections are air-dried and fixed, usually in acetone or methanol. Aldehyde... 

Tissues are fixed with formalin for 18 hr to 4 weeks and then embedded in paraffin. Sections (4 pm thick) are mounted onto superfrost or poly-L-lysine-coated glass slides, dried in an oven for 1 hr at 60°C, and deparaffmized with three changes of xylene. This is followed by rehydration through a series of descending concentrations of ethanol. The slides are placed... 

Paraffin sections (6 p,m thick) of formalin-fixed tissues are mounted onto silanized glass slides and air-dried at 60°C (Henke and Ayhan, 1994). They are deparaffinized, rehydrated, and air-dried. The slides are placed in aplastic Coplinjar filled with lOmM sodium citrate buffer (pH 6.0) and microwaved (720 W) for 1 min this time is measured after reaching the boiling point. After treating with 1 M sodium thiocyanate for 10 min at 80°C, the sections are washed with distilled water and then digested with pepsin (3mg/ml in 0.2 N HC1) for 6 min at 37°C. Both the heating and the pepsin digestion durations must be... 

Twenty human coronary tissue sections were obtained postmortem and mounted in paraffin onto low-e glass slides for IR microspectroscopy. A visible light image of a stained section of human coronary atherosclerotic plaque appears in Figure 34.7. This section was adjacent to the section used for IR microspectrometric imaging (see Figure 34.8). 

For dehydration and paraffin embedding, brains are rinsed in tap water for 30 min and subsequendy incubated in a series of graded alcohols consisting of 50 %, 60 %, 70 %, 80 %, and 90 % ethanol for 1 h each, followed by two incubation steps in absolute ethanol. Finally, tissues are immersed in xylene for 1 h and transferred into preheated, liquid paraffin. Brains are embedded in paraffin blocks and processed into 4- rm-thick sections using a sliding microtome. Sections are mounted onto microscope slides and dried for at least 16 h for subsequent immunohistochemical applications. 

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