Application of a blue-green chromogenic reagent in immunohistochemical staining of melanoma tissue
WANG Yahui
LIU Lulu
LIU You
NING Haoyong
Abstract：Objective To investigate the application of a novel immunohistochemical staining reagent, Duplex Green, in the immunohistochemical staining of melanoma tissues. Methods Three paraffin blocks of melanoma tissues from our department were used as samples. For each sample, immunohistochemical staining was performed using S100 as the marker, including Duplex Green staining without melanin removal, DAB staining without melanin removal, and DAB staining after melanin removal. The results of the three methods were compared to evaluate the feasibility of Duplex Green staining. Results In the immunohistochemical staining with Duplex Green without melanin removal, the positive signals appeared as bright blue-green, which could be clearly distinguished from endogenous melanin. In contrast, DAB staining without melanin removal resulted in brownish coloration, which could not be differentiated from the endogenous pigments in the tissue, making it difficult to accurately interpret the results. After melanin removal, DAB staining showed brownish positive signals without melanin interference, and the expression location and intensity were consistent with those observed in the Duplex Green staining without melanin removal. Conclusion Duplex Green is a novel HRP staining reagent that produces bright blue-green staining, which can be well distinguished from endogenous pigments in tissues. It is suitable for immunohistochemical staining of tissues rich in endogenous pigments. Compared to the DAB staining method, this reagent eliminates the need for melanin removal, simplifying the immunohistochemical procedure. Additionally, melanin removal may reduce the antigenicity of the tissue, and the use of Duplex Green can avoid this effect.
Keywords：ImmunohistochemistryMelanomaHorseradish peroxidaseStaining reagentEndogenous pigment
Publication Date：2025-08-28
Online Publishing Date：2025-09-18(First online date of this platform, not the publication date of the document)
Pages：3( 1052-1054 )