Barsky S H, Rao N C, Restrepo C, Liotta L A
Am J Clin Pathol. 1984 Aug;82(2):191-4. doi: 10.1093/ajcp/82.2.191.
Basement membrane zone antigens, laminin, Type IV collagen, and Type V collagen each are enhanced selectively in formalin-fixed, paraffin-embedded sections by pretreatment with pepsin (1 mg pepsin/mL 0.5 M acetic acid). Highly specific antibodies to laminin, Type IV collagen, and Type V collagen each demonstrate intense linear staining of epithelial and endothelial basement membranes in fresh tissue, but this staining is diminished markedly and often completely abolished in paraffin-embedded tissue. Pretreatment of this paraffin-embedded tissue with standard immunoperoxidase enhancement technics such as trypsin fails to increase immunoreactivity of these antigens. Pretreatment with other proteases with known collagenolytic activities such as bacterial collagenase and Type IV collagenase is likewise ineffective. In contrast, pepsin pretreatment markedly enhances immunoreactivity of laminin, Type IV collagen, and Type V collagen. Previous immunocytochemical studies of the basement membrane useful in the distinction of invasive tumors from their benign counterparts, for example, tubular carcinoma of the breast from sclerosing adenosis, which only could be done prospectively in fresh tissue now can be performed retrospectively in paraffin-embedded tissue.
基底膜区抗原、层粘连蛋白、IV型胶原蛋白和V型胶原蛋白，经胃蛋白酶（1mg胃蛋白酶/mL 0.5M乙酸）预处理后，在福尔马林固定、石蜡包埋切片中均有选择性增强。针对层粘连蛋白、IV型胶原蛋白和V型胶原蛋白的高度特异性抗体，在新鲜组织中均显示上皮和内皮基底膜有强烈的线性染色，但在石蜡包埋组织中这种染色明显减弱，且常常完全消失。用标准免疫过氧化物酶增强技术（如胰蛋白酶）对这种石蜡包埋组织进行预处理，无法增加这些抗原的免疫反应性。用其他具有已知胶原酶活性的蛋白酶（如细菌胶原酶和IV型胶原酶）进行预处理同样无效。相比之下，胃蛋白酶预处理可显著增强层粘连蛋白、IV型胶原蛋白和V型胶原蛋白的免疫反应性。以前对基底膜进行的免疫细胞化学研究有助于区分浸润性肿瘤与其良性对应物，例如乳腺管状癌与硬化性腺病，以前只能在新鲜组织中进行前瞻性研究，现在可以在石蜡包埋组织中进行回顾性研究。
