Nakamura T, Nagura H, Komatsu N, Watanabe K
Virchows Arch A Pathol Anat Histopathol. 1985;406(3):367-72. doi: 10.1007/BF00704305.
The intracellular transport mechanism of secretory immunoglobulin A (sIgA) has been immunocytochemically defined in human submandibular glands. To examine the properties of the intracytoplasmic vesicles which contain IgA, the enzyme labeled antibody method for SC and IgA and Novikoff's method for acid phosphatase (ACPase) activity were employed on the same sections. The intracytoplasmic vesicles containing IgA and SC in the serous acinar cells were free of ACPase activity and were thus distinguishable from lysosomes. Neither IgA nor SC was localized in the secretory granules. Lactoferrin was localized in the secretory granules and glandular lumen of the serous acinar cells, but not in the cytoplasmic vesicles, which were also free of ACPase activity. These findings suggests that the transport of sIgA was performed by intracytoplasmic vesicles and that lactoferrin is discharged from secretory granules into the lumen and finally makes a "rendezvous" with sIgA in the lumen of acinar cells.
分泌型免疫球蛋白A（sIgA）的细胞内转运机制已通过免疫细胞化学方法在人类下颌下腺中得以明确。为了研究含有IgA的胞质内囊泡的特性，在同一切片上采用了针对分泌成分（SC）和IgA的酶标抗体法以及用于酸性磷酸酶（ACPase）活性检测的诺维科夫法。浆液性腺泡细胞中含有IgA和SC的胞质内囊泡无ACPase活性，因此可与溶酶体区分开来。IgA和SC均未定位在分泌颗粒中。乳铁蛋白定位在浆液性腺泡细胞的分泌颗粒和腺腔内，但不在同样无ACPase活性的胞质囊泡中。这些发现表明，sIgA的转运是通过胞质内囊泡进行的，并且乳铁蛋白从分泌颗粒释放到腺腔内，最终在腺泡细胞腔内与sIgA“会合”。
