Re-evaluation of melanin bleaching using warm diluted hydrogen peroxide for histopathological analysis.
Pathol Int
; 61(6): 345-50, 2011 Jun.
Article
em En
| MEDLINE
| ID: mdl-21615609
ABSTRACT
Excessive amounts of melanin pigments may hamper histopathological assessments of melanocytic lesions by obscuring cellular morphology and hindering antibody-antigen interactions. To determine the optimal melanin-bleaching conditions for histopathological examination, heavily pigmented melanomas were treated with warm hydrogen peroxide (H2O2) diluted with various diluents (1% disodium hydrogen phosphate 12H2O (Na2 HPO4); phosphate buffer 0.05 M, pH 7.4 (PB); and PBS 0.05 M, pH 7.4) at varying temperatures (50°C, 55°C, and 60°C) and for varying incubation times (0.5, 1, 2, and 3 h). The effect of the sequential order of antigen retrieval and bleaching on preserving tissue morphology was then evaluated. Additionally, the effect of melanin bleaching using warm diluted H2O2 on the antigenicity of melanoma-related markers (HMB-45, MART-1, and S-100) and other markers used for histopathology was examined in amelanotic melanomas and tonsil tissue. Optimal and complete bleaching was achieved using warm 3% H2O2 in PB treatment at 55°C for 2 h following antigen retrieval with microwaving or digestion with trypsin. Under these conditions, the tissue morphology and antigenicity of various immunohistochemical markers were also well preserved. Bleaching with warm 3% H2O2 PB is a fast and efficient method of bleaching melanin pigments and performing immunohistochemical examination in heavily melanin-pigmented lesions.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Neoplasias Cutâneas
/
Tonsila Palatina
/
Imuno-Histoquímica
/
Melanoma Amelanótico
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Melaninas
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Melanoma
Tipo de estudo:
Evaluation_studies
Limite:
Humans
Idioma:
En
Revista:
Pathol Int
Assunto da revista:
PATOLOGIA
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Japão