Tobacman J K, Walters K S
Department of Internal Medicine, University of Iowa, Iowa City 52242-1081, USA.
Cancer Detect Prev. 2001;25(6):520-6.
The purpose of this investigation was to characterize the ultrastructural changes that occur in mammary myoepithelial cells (MMEC) following exposure in tissue culture to low concentrations of lambda-carrageenan, a sulfated polysaccharide commonly used as a food additive. MMEC were obtained from reduction mammoplasty, grown in tissue culture, exposed for varying durations to low concentrations (0.0014%-0.0001%) of lambda-carrageenan, and examined by transmission electron microscopy, following staining for acid phosphatase and for aryl sulfatase. Carrageenan appeared to enter the cells by membrane-associated endocytic vesicles and accumulate in endosomes and lysosomes. Unusual lamellar inclusions were identified within lysosomes of the MMEC, and lysosomal vacuolation arose in association with the inclusions. The observed changes appeared to lead to destruction of the MMEC by release of proteolytic enzymes from the distorted lysosomes, similar to the process observed in lysosomal storage diseases.
本研究的目的是描述在组织培养中，乳腺肌上皮细胞（MMEC）暴露于低浓度的λ-角叉菜胶（一种常用作食品添加剂的硫酸化多糖）后所发生的超微结构变化。MMEC取自缩乳术患者，在组织培养中生长，暴露于不同时间的低浓度（0.0014%-0.0001%）λ-角叉菜胶中，然后在对酸性磷酸酶和芳基硫酸酯酶进行染色后，通过透射电子显微镜检查。角叉菜胶似乎通过与膜相关的内吞小泡进入细胞，并积聚在内体和溶酶体中。在MMEC的溶酶体内发现了异常的层状内含物，并且溶酶体空泡化与这些内含物有关。观察到的变化似乎导致MMEC因扭曲的溶酶体释放蛋白水解酶而被破坏，这类似于在溶酶体贮积症中观察到的过程。
