Adhesion molecules in normal and pathological corneas. An immunohistochemical study using monoclonal antibodies.
BACKGROUND
Adhesion molecules are cell surface receptors that are probably important in various cell-cell and cell-extracellular matrix interactions of the cornea.


METHODS
In this immunohistochemical light-microscopic study we analyzed the expression pattern of adhesion molecules in normal and pathological human corneas (cases of corneal inflammation and degenerative disorders). The analyzed molecules included the beta 1 integrin or VLA family VLA-1-6, the beta 2 integrins or leukocyte integrins LFA-1, Mac-1, and p150,95, the immunoglobulins LFA-3, CD2, ICAM-1 and VCAM-1 and the selectins ELAM-1 and GMP-140.


RESULTS
Inflamed cornea (in contrast to normal cornea). On corneal epithelium, increased expression of the alpha 2 subunit of VLA-2 was detected and ICAM-1 was induced on the basal epithelial cells. On corneal stromal keratocytes, LFA-3 was induced and expression of the alpha subunits of VLA-1-6 and ICAM-1 was increased. On vascular endothelium, VCAM-1 and ELAM-1 were induced and ICAM-1 and GMP-140 expression was increased. On corneal endothelium, ELAM-1 was induced and increased levels of the alpha 1 subunit of VLA-1 and GMP-140 were expressed. Degenerative disorders (in contrast to normal cornea): In corneas with degenerative disorders we found decreased expression of adhesion molecules.


CONCLUSIONS
Inflammatory cytokines increase the expression of the adhesion molecules. Increased expression of the VLAs probably promotes cell-extracellular matrix and cell-cell interactions. ICAM-1, VCAM-1, LFA-3, ELAM-1 and GMP-140 expression was increased on vascular endothelium in inflamed corneas. Corresponding receptors on leukocytes probably enable a selective recruitment of different leukocyte populations in inflammatory corneal diseases. The decreased expression of adhesion molecules in corneal degenerative disorders is probably a sign of reduced cell-cell and cell-extracellular matrix interactions.
Vorkauf
W
W
Zentrum Zahn-, Mund- und Kieferheilkunde, Operative Medizin II der Christian-Albrechts-Universität zu Kiel, Germany.
Vorkauf
M
M
Nölle
B
B
Duncker
G
G
D000911:Antibodies, Monoclonal; D015815:Cell Adhesion Molecules / Q000096:biosynthesis*; D003315:Cornea / Q000378:metabolism*; D003317:Corneal Dystrophies, Hereditary / Q000378:metabolism*; D003319:Corneal Stroma / Q000378:metabolism; D004728:Endothelium, Corneal / Q000378:metabolism; D004848:Epithelium / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D007634:Keratitis / Q000378:metabolism*; D007640:Keratoconus / Q000378:metabolism*
D000911:Antibodies, Monoclonal; D015815:Cell Adhesion Molecules