Acetic acid treatment for wrinkle-free oral mucosal epithelia in paraffin section preparation.
For histopathological assessment of oral borderline malignancies, it is important to carefully detect subtle epithelial changes on fully stretched tissue sections. However, it is not generally easy to obtain wrinkle-free sections when using formalin-fixed paraffin-embedded oral mucosal samples. Since acetic acid treatment is already utilized for large brain tissue sections, we examined whether that treatment was also effective for oral mucosal tissues containing normal to malignant epithelial lesions. Paraffin sections were floated in various concentrations of acetic acid for 10 min after stretching in water for 1 min, then wrinkle formations were examined using hematoxylin and eosin staining, as well as for staining intensity with keratin immunohistochemistry. Wrinkles were formed in both epithelial and connective tissue zones of sections treated with less than a 40-mM (0.25%) concentration of acetic acid. In contrast, treatments with concentrations at 80 mM (0.5%) and higher resulted in cracking between the epithelial layer and lamina propria, as well as poor immunohistochemical results for keratins 13 and 17, even though the wrinkles completely disappeared. These results indicate that 40 mM is the optimal concentration of acetic acid solution to prevent wrinkles in the epithelial layer while maintaining the immunohistochemical qualities of oral mucosa tissue sections, especially those containing borderline malignant epithelial lesions.
Ahsan
Md Shahidul
MS
Division of Oral Pathology, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, Gakkocho-dori, Chuo-ku, Niigata 951-8514, Japan.
Maruyama
Satoshi
S
Cheng
Jun
J
Al-Eryani
Kamal
K
Yamazaki
Manabu
M
Hasegawa
Mayumi
M
Tsuneki
Masayuki
M
Saku
Takashi
T
D019342:Acetic Acid / Q000378:metabolism*; D014408:Biomarkers, Tumor; D019343:Citric Acid / Q000378:metabolism*; D003238:Connective Tissue / Q000502:physiology; D004848:Epithelium / Q000502:physiology; D006801:Humans; D053535:Keratin-13 / Q000737:chemistry; D053537:Keratin-17 / Q000737:chemistry; D009061:Mouth Mucosa / Q000502:physiology*; D009062:Mouth Neoplasms / Q000175:diagnosis*; D016612:Paraffin Embedding / Q000379:methods*; D013048:Specimen Handling / Q000379:methods; D014059:Tongue / Q000502:physiology
D014408:Biomarkers, Tumor; C507426:KRT13 protein, human; D053535:Keratin-13; D053537:Keratin-17; D019343:Citric Acid; D019342:Acetic Acid