Hatta Hideki, Nishida Takeshi, Minamisaka Takashi, Tsuneyama Koichi, Imura Johji
Department of Diagnostic Pathology, University of Toyama, Toyama, JPN.
Department of Pathology and Laboratory Medicine, Tokushima University, Tokushima, JPN.
Cureus. 2021 Aug 29;13(8):e17549. doi: 10.7759/cureus.17549. eCollection 2021 Aug.
Antigen modification and denaturation are recognized causes of false negatives in immunostaining. Specimens that have been stored for an extended period at room temperature show decreased immunoreactivity and may mislead the diagnosis. Studies of the molecular targeting of drugs often involve immunostaining of previous samples and, in some situations, only unstained specimens can be used. The present study aimed to develop an effective staining method to recover antigen activation in unstained specimens stored for an extended period by using ethylene-diamine-tetraacetic acid (EDTA) buffer solution with boric acid. We compared several commonly used antigen retrieval solutions and found that Tris-borate-EDTA (TBE) buffer solution with a pH ≥8.3 provided sufficient antigen retrieval. However, pH values higher than 8.3 (9.0, 10.0, and 11.0) frequently caused severe tissue damage. Thus, TBE with pH 8.3 was the most suitable antigen retrieval solution for recovering the antigenicity of specimens stored for an extended period. This procedure may allow useful immunohistochemical information, even from sections that have been stored for an extended period.
抗原修饰和变性是免疫染色中出现假阴性结果的公认原因。在室温下长时间保存的标本显示免疫反应性降低，可能会误导诊断。药物分子靶向研究通常涉及对先前样本进行免疫染色，在某些情况下，只能使用未染色的标本。本研究旨在开发一种有效的染色方法，通过使用含硼酸的乙二胺四乙酸（EDTA）缓冲溶液来恢复长时间保存的未染色标本中的抗原活性。我们比较了几种常用的抗原修复溶液，发现pH≥8.3的Tris-硼酸-EDTA（TBE）缓冲溶液能提供足够的抗原修复效果。然而，高于8.3（9.0、10.0和11.0）的pH值经常会导致严重的组织损伤。因此，pH 8.3的TBE是恢复长时间保存标本抗原性的最合适抗原修复溶液。即使是从长时间保存的切片中，这一程序也可能获取有用的免疫组化信息。
