Identification of a marker antigen for the endocytic stage of intestinal development in rat, sheep, and human.
Identification of a marker antigen for the endocytic stage of intestinal development in rat, sheep, and human.
复制标题
鉴定大鼠、绵羊和人类肠道发育内吞阶段的标记抗原。
DOI：
10.1097/00005176-199510000-00005
复制
发表时间：
1995
影响因子：
2.9
通讯作者：
Neutra,MR
中科院分区：
文献类型：
--
作者：
Trahair,JF;Wilson,JM;Neutra,MR
Vacuolated enterocytes are highly endocytic epithelial cells present in intestines of diverse mammalian species during neonatal and/or fetal development. Using monoclonal antibodies raised against membrane frac-tions, we previously identified a 55–61 kd membrane glycoprotein that is restricted to apical endosomal tubules of vacuolated enterocytes in fetal and suckling rats. To determine whether this cell-specific antigen is present in vacuolated enterocytes of fetal sheep or humans, the endosomal antigen was immuno-affinity purified from rats and used to generate and purify specific rabbit polyclonal antibodies, Light microscopic and electron microscopic immunocytochemistry showed that antigens cross-reactive with the rat endosomal antigen are present in vacuolated enterocytes of fetal sheep and fetal human small intestine and are restricted to apical endosomal tubules in these cells. Immunoblot analysis of tissue extracts from fetal human intestines showed antigen (s) at 55 and 60 kd, as well as a major form at 130 kd. Cross-reactive antigen (s) from fetal sheep intestines appeared as 42-and 50-kd bands. Although the molecular identities of the sheep and human antigens are not yet established, these results show that these antigens can serve as mark-ers for the endocytic stage of intestinal development in humans as well as other mammals. Key Words: Fetal humans–Fetal sheep-Intestinal development–Enterocytes–Endocytosis.In a wide variety of mammalian species, enterocytes of the developing intestine pass through a stage of intense endocytic activity (1–3). For many years it has been recognized that a specialized type of absorptive epithelial cell, the “vacuolated en-terocyte,” is responsible for endocytosis of intact proteins during this developmental stage. This cell type has been studied most extensively in rats, a species in which the endocytic period occurs post-natally, during the 3-week suckling phase (4). Endocytosis by vacuolated enterocytes in the suckling rat ileum results in massive uptake and intracellular digestion of milk (5, 6) at a stage when lumenal pro-
