Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Ultrastructural localization of sulfated and unsulfated keratan sulfate in normal and macular corneal dystrophy type I.
AU - Lewis, David
AU - Davies, Yvonne
AU - Nieduszynski, Ian A.
AU - Lawrence, Fiona
AU - Quantock, Andrew J.
AU - Bonshek, Richard
AU - Fullwood, Nigel J.
PY - 2000/3
Y1 - 2000/3
N2 - Keratan sulfate (KS) proteoglycans are of importance for the maintenance of corneal transparency as evidenced in the condition macular corneal dystrophy type I (MCD I), a disorder involving the absence of KS sulfation, in which the cornea becomes opaque. In this transmission electron microscope study quantitative immuno- and histochemical methods have been used to examine a normal and MCD I cornea. The monoclonal antibody, 5-D-4, has been used to localize sulfated KS and the lectin Erythrina cristagalli agglutinin (ECA) to localize poly N-acetyllactosamine (unsulfated KS). In normal cornea high levels of sulfated KS were detected in the stroma, Bowman’s layer, and Descemet’s membrane and low levels in the keratocytes, epithelium and endothelium. Furthermore, in normal cornea, negligible levels of labeling were found for N-acetyllactosamine (unsulfated KS). In the MCD I cornea sulfated KS was not detected anywhere, but a specific distribution of N-acetyllactosamine (unsulfated KS) was evident: deposits found in the stroma, keratocytes, and endothelium labeled heavily as did the disrupted posterior region of Descemet’s membrane. However, the actual cytoplasm of cells and the undisrupted regions of stroma revealed low levels of labeling. In conclusion, little or no unsulfated KS is present in normal cornea, but in MCD I cornea the abnormal unsulfated KS was localized in deposits and did not associate with the collagen fibrils of the corneal stroma. This study has also shown that ECA is an effective probe for unsulfated KS.
AB - Keratan sulfate (KS) proteoglycans are of importance for the maintenance of corneal transparency as evidenced in the condition macular corneal dystrophy type I (MCD I), a disorder involving the absence of KS sulfation, in which the cornea becomes opaque. In this transmission electron microscope study quantitative immuno- and histochemical methods have been used to examine a normal and MCD I cornea. The monoclonal antibody, 5-D-4, has been used to localize sulfated KS and the lectin Erythrina cristagalli agglutinin (ECA) to localize poly N-acetyllactosamine (unsulfated KS). In normal cornea high levels of sulfated KS were detected in the stroma, Bowman’s layer, and Descemet’s membrane and low levels in the keratocytes, epithelium and endothelium. Furthermore, in normal cornea, negligible levels of labeling were found for N-acetyllactosamine (unsulfated KS). In the MCD I cornea sulfated KS was not detected anywhere, but a specific distribution of N-acetyllactosamine (unsulfated KS) was evident: deposits found in the stroma, keratocytes, and endothelium labeled heavily as did the disrupted posterior region of Descemet’s membrane. However, the actual cytoplasm of cells and the undisrupted regions of stroma revealed low levels of labeling. In conclusion, little or no unsulfated KS is present in normal cornea, but in MCD I cornea the abnormal unsulfated KS was localized in deposits and did not associate with the collagen fibrils of the corneal stroma. This study has also shown that ECA is an effective probe for unsulfated KS.
U2 - 10.1093/glycob/10.3.305
DO - 10.1093/glycob/10.3.305
M3 - Journal article
VL - 10
SP - 305
EP - 312
JO - Glycobiology
JF - Glycobiology
SN - 1460-2423
IS - 3
ER -