Concerning bidirectional transport by the lymphoid follicle-associated epithelial cells
Lupetti, M.; Dolfi, A.
Cellular and Molecular Biology Including Cyto-Enzymology 26(6): 609-613
1980
ISSN/ISBN: 0145-5680 PMID: 6260359 Document Number: 167621
Follicle-associated epithelial (FAE) cells are capable of transporting material from the intestinal lumen to the associated lymphoid follicles. Bockman and Stevens (1977) maintained that these cells can transport endovenously (e.v.) injected peroxidase from the blood vessels to the intestinal lumen. The idea of bidirectional transport by the FAE cells was thus introduced. Injected peroxidase may have gained access to the bursa of chicks, the rabbit appendix and the intestinal lumen in mice in different ways, possibly via the FAE cells of these organs. If this enzyme was excreted by the chick kidney and by the rabbit and mouse liver; it could have reached the absorbent cells of the bursa of Fabricius in chicks, the rabbit appendix and the mouse Peyer's patches by flowing through the intestinal lumen. To test this hypothesis horseradish peroxidase type II, in the same doses used by Bockman and Stevens, was injected e.v. into these animals. The urine of chicks and the rabbit and mouse bile was collected using surgical techniques before e.v. administration of the peroxidase and during the 15 min following it. Tests carried out on the fluids excreted before injection did not reveal any trace of peroxidase activity, while liquids collected after injection showed peroxidase activity. The presence of peroxidase in the lumen of the bursa of Fabricius in chicks, in the rabbit appendix and in the mouse gut and its appearance in the FAE cells of these organs might be due to the removal of this substance by the kidneys in the chicks and by the liver in the rabbits and mice. Further investigations are necessary before bidirectional transport by the FAE cells is proven to exist.