Study on staining methods for mast cells in the nasal mucosa

Area of Science:

• Immunohistochemistry
• Cell Biology
• Histology

Background:

• Mast cells, including mucosal mast cells (MMC) and connective tissue mast cells (CTMC), are present in various organs.
• Understanding mast cell distribution in the nasal mucosa is crucial for allergy research.

Purpose of the Study:

• To determine the most effective staining and fixation methods for visualizing mast cells in the nasal mucosa.
• To characterize nasal mast cells as either MMC or CTMC.

Main Methods:

• Comparison of two fixatives: neutral buffered formalin and Carnoy's solution.
• Evaluation of five staining solutions: toluidine blue (TB) at pH 0.5, 2.5, and 4.0, 0.4 M MgCl2-alcian blue (AB), and naphthol AS-D chloracetate (NAS-DC).
• Immunohistochemical staining for tryptase was used as a positive control.

Main Results:

• Carnoy's fixative combined with pH 0.5 TB staining yielded the highest number of mast cells, particularly in the epithelial layer.
• The number of mast cells identified by pH 0.5 TB staining correlated with those identified by pH 0.5 AB and tryptase immunohistochemistry.
• Carnoy's fixation and pH 0.5 TB staining revealed significantly more mast cells in the nasal mucosa compared to formalin fixation.

Conclusions:

• Fixation with Carnoy's solution and staining with pH 0.5 toluidine blue are the most effective and simplest methods for identifying mast cells in the nasal mucosa.
• This method is particularly useful for studying mast cells in the context of nasal allergies.