Modification of Luna's technique for staining eosinophils in the hamster cheek pouch

Abstract

The cheek pouch is an anatomical peculiarity of hamsters, widely used as an experimental model for oral cancer, and characterization of its normal cell populations and the changes they undergo in pathological conditions is of great interest. Our studies of epithelium-connective tissue interactions have revealed that hamster eosinophils are not easily recognizable because they are small and exhibit a larger nucleus:cytoplasm ratio than those in human and other animal tissues. Luna's technique is the most popular specific staining technique for eosinophils. Owing to the morphology of hamster eosinophils, however, it was necessary to modify Luna's technique to stain these cells selectively against a more contrasting background that would enable their identification and quantitation in the hamster cheek pouch. The modification involved staining the sections with a solution of 0.5% Biebrich scarlet in lithium carbonate followed by counterstaining with 1% metanil yellow in water. The eosinophils were stained selectively red against a yellow background. Our technique avoided nuclear staining and enhanced observation of selectively stained granules in a scarce cytoplasm with a contrasting background, which permits fast, reproducible studies and automated image analysis.

Trichinella spiralis infection rapidly induces lung inflammatory response

“…The results were expressed as the number of goblet cells/100 epithelial cells. The eosinophil and mast cell counts in the lung parenchyma were completed in sections stained with the modified Luna's methodology (Tomasi et al 2008) and Toluidine blue (CI 50240; Merck, Darmstadt, Germany) (Tomasi et al 2003), respectively. The eosinophils and mast cells were counted in 100-150 randomly selected fields for each sample at 400× magnification employing a grid with a known area (62,500 m 2 at 400× magnification) attached to a microscope ocular (Olympus, Tokyo, Japan).…”

Luna stain, an improved selective stain for detection of microsporidian spores in histologic sections

“…The Luna stain was originally developed to detect cytoplasmic granules within eosinophils, Negri bodies, erythrocytes and phagocytes (Luna 1968, Tomasi et al 2008). It also has been used to highlight elastin in tissue sections (Kligman 1981).…”

Sex differences in the influence of obesity on a murine model of allergic lung inflammation

“…The lungs were fixed in 4% formalin and then cut into 5 µm slices and stained. The specific visualization of eosinophils was made using the Luna staining specific for eosinophils, as described elsewhere (Fisher Scientific) . With this method, eosinophils stained strongly in red and were imaged using a light microscope.…”