Expression and distribution of junctional adhesion molecule-1 in the human cornea.
OBJECTIVE
To investigate the expression and distribution of junctional adhesion molecule 1 (JAM-1) in human corneal tissue and cells.


METHODS
Reverse transcriptase-polymerase chain reaction was used to detect the expression of JAM-1, ZO-1, and occludin mRNAs in corneal cells, while the presence of JAM-1 protein was analyzed by flow cytometry (FACS). Double immunofluorescence staining was used to determine the tissue distribution of JAM-1 and occludin in human corneas.


RESULTS
Strong expression of JAM-1, ZO-1, and occludin mRNAs was observed in primary cultured corneal epithelial and endothelial cells, but not in primary cultured keratocytes. The expression of JAM-1 protein in cultured epithelial and endothelial cells was confirmed by FACS. When keratocytes were cultured in medium with 10% fetal calf serum for several passages, differentiation into corneal myofibroblasts occurred. The expression of JAM-1 was detected in these corneal myofibroblasts at both RNA and protein levels. JAM-1 immunoreactivity was seen at cell borders throughout the entire epithelium, but not in keratocytes from normal corneal tissue. On the other hand, JAM-1 immunoreactivity was detected in the cytoplasm of corneal endothelial cells.


CONCLUSIONS
JAM-1 is expressed by human corneal epithelial and endothelial cells, but not by keratocytes, although its expression is induced in corneal myofibroblasts.
D015815:Cell Adhesion Molecules / Q000235:genetics* / Q000378:metabolism; D002478:Cells, Cultured; D003315:Cornea / Q000166:cytology; D004728:Endothelium, Corneal / Q000378:metabolism*; D019573:Epithelium, Corneal / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism; D005434:Flow Cytometry; D019084:Fluorescent Antibody Technique, Indirect; D015870:Gene Expression; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D062793:Occludin; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D062826:Zonula Occludens-1 Protein
D015815:Cell Adhesion Molecules; C407243:F11R protein, human; D008565:Membrane Proteins; C568985:OCLN protein, human; D062793:Occludin; D010750:Phosphoproteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C569042:TJP1 protein, human; D062826:Zonula Occludens-1 Protein