Platelet endothelial cell adhesion molecule-1 is expressed in adenoidal crypt epithelial cells.
The adenoidal epithelial crypt is a potential site of antigen transport from pharyngeal lumen to adenoidal tissue. The base of the crypt is consistently infiltrated with leucocytes, forming a reticular lymphoepithelial structure. To evaluate mechanisms that possibly mediate leucocyte infiltration, expressions of leucocyte adhesion molecules, such as platelet endothelial cell adhesion molecule-1 (PECAM-1) (CD31), vascular cell adhesion molecule-1 (VCAM-1) (CD106) and intercellular adhesion molecule-1 (ICAM-1) (CD54), were studied in the adenoidal epithelial crypt. Epithelial cells in the outer opening of the adenoidal crypt were positive for VCAM-1, whereas epithelial cells at the base of the crypt were positive for PECAM-1. Isolated ICAM-1-expressing cells were found throughout the epithelial crypt. Double immunofluorescence staining revealed that the epithelial cells positive for PECAM-1 or VCAM-1 were positive for cytokeratin. The expression of PECAM-1 in the base and VCAM-1 at the orifice of the adenoidal epithelial crypt implies that the base and the orifice of the crypt have a distinct ability to recruit leucocytes. Epithelial cells expressing PECAM-1 may have a role in the formation of the reticular lymphoepithelial structure in the epithelial crypt.
Pajusto
M
M
Department of Otorhinolaryngology, Helsinki University Central Hospital, Helsinki, Finland.
Tarkkanen
J
J
Mattila
P S
PS
D000234:Adenoids / Q000166:cytology / Q000276:immunology*; D002675:Child, Preschool; D004847:Epithelial Cells / Q000276:immunology; D005455:Fluorescent Antibody Technique; D006801:Humans; D007223:Infant; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism*; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism
D019408:Platelet Endothelial Cell Adhesion Molecule-1; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1