Zhou Xiaoge, Wang Peng, Lu Ming, Liu Lina, Zhang Yanning, Zhang Shuhong, Chen Guangyong, Zhang Changhuai, Huang Shoufang
Department of Pathology, Beijing Friendship Hospital, Capital University of Medical Sciences, Beijing 100050, China.
Zhonghua Bing Li Xue Za Zhi. 2002 Dec;31(6):491-6.
To study the influence of heat-induced epitope retrieval (HIER) on endogenous avidin-binding activity (EABA) and to establish an effective way to block EABA in immunohistochemistry.
Systematically screening EABA in 164 (679 samples) formalin-fixed and paraffin-embedded human tissues including 76 (102 samples) normal tissues and 88 (577 samples) tumor tissues as well as 4 (80 samples) formalin-fixed and paraffin-embedded rat normal tissues using tissue array (tissue chip), HIER, immunohistochemistry and egg white solution blocking. In addition, EABA was also examined in 9 (15 samples) human frozen tissues.
(1) EABA was detected in frozen tissues. (2) No staining for EABA was seen in formalin-fixed and paraffin-embedded tissues. (3) EABA was revealed after the tissues treated with microwave HIER. (4) The density of signal for EABA was variable from tissue to tissue and cell to cell. (5) The signals of EABA expressed in scatter or diffuse in tissues and in granular form in cytoplasm. (6) EABA was found in a wide range of epithelial tissues, especially in gland epithelia of normal and tumor tissues. These included kidney, adrenal cortex, liver, C cells of thyroid gland, oxyphil cells of parathyroid, fundal gland of stomach, sebaceous gland of skin, duct of salivary; oncocytoma and papillary adenocarcinoma of kidney and thyroid gland, adenolymphoma of parotid, carcinoma of liver cell, adenocarcinoma of stomach, colon, prostate, gall bladder and endometrium, and so on. (7) EABA was easier revealed by higher pH value buffer (EGTA pH 9.0) than that with lower pH value (EDTA pH 8.0 and citrate pH 6.0). (8) The revealed EABA could be effectively blocked using 20% egg white solution.
HIER could unmask EABA in formalin-fixed and paraffin-embedded tissues. The unmasked EABA present in a wide range of human normal and tumor tissues as well as in rat normal tissues. The EABA could influence routine immunohistochemistry staining when using (strept)avidin-horseradish peroxidase detective system. The egg white solution could effectively block EABA and eliminate the influence of EABA on immunohistochemistry.
研究热诱导抗原修复（HIER）对内源性抗生物素蛋白结合活性（EABA）的影响，并建立一种在免疫组织化学中阻断EABA的有效方法。
使用组织芯片（组织微阵列）、HIER、免疫组织化学和蛋清溶液阻断法，系统筛选164例（679个样本）福尔马林固定石蜡包埋的人体组织中的EABA，其中包括76例（102个样本）正常组织、88例（577个样本）肿瘤组织以及4例（80个样本）福尔马林固定石蜡包埋的大鼠正常组织。此外，还对9例（15个样本）人体冷冻组织中的EABA进行了检测。
（1）在冷冻组织中检测到EABA。（2）在福尔马林固定石蜡包埋的组织中未观察到EABA染色。（3）经微波HIER处理后的组织中显示出EABA。（4）EABA的信号密度在组织与组织之间以及细胞与细胞之间存在差异。（5）EABA的信号在组织中呈散在或弥漫性表达，在细胞质中呈颗粒状。（6）在多种上皮组织中发现了EABA，尤其是正常和肿瘤组织的腺上皮。这些组织包括肾脏、肾上腺皮质、肝脏、甲状腺C细胞、甲状旁腺嗜酸性细胞、胃底腺、皮肤皮脂腺、唾液腺导管；肾和甲状腺的嗜酸细胞瘤和乳头状腺癌、腮腺腺淋巴瘤、肝细胞癌、胃腺癌、结肠腺癌、前列腺癌、胆囊癌和子宫内膜癌等。（7）较高pH值缓冲液（EGTA pH 9.0）比低pH值缓冲液（EDTA pH 8.0和柠檬酸盐pH 6.0）更容易显示出EABA。（8）使用20%蛋清溶液可有效阻断显示出的EABA。
HIER可使福尔马林固定石蜡包埋组织中的EABA暴露。暴露的EABA存在于多种人体正常和肿瘤组织以及大鼠正常组织中。当使用（链）抗生物素蛋白-辣根过氧化物酶检测系统时，EABA可能影响常规免疫组织化学染色。蛋清溶液可有效阻断EABA并消除其对免疫组织化学的影响。
