involucrin and Corneal-Diseases

To investigate the protective effects of c-Jun N-terminal kinase (JNK)-1 and -2 gene knockout (KO) on the corneal epithelial response to desiccating stress.. The C57BL/6, JNK1KO, and JNK2KO mice were subjected to desiccating stress (DS) for 5 days. The effects of DS on the corneal epithelium were evaluated by measuring corneal smoothness and permeability. Expression of matrix metalloproteinases (MMP)-1, MMP-9, and cornified envelope protein precursors (small proline-rich protein [SPRR]-1a, SPRR-2a, and involucrin) in the corneal epithelia was evaluated by immunostaining and real-time polymerase chain reaction. Collagenase and gelatinase activity in corneal sections as measured with in situ fluorescent assays.. The JNK2KO mice had smoother corneal surfaces and less corneal barrier disruption in response to DS than JNK1KO mice and C57BL/6 wild-type control mice. The DS increased levels of MMP-1, MMP-9, SPRR-1a, SPRR-2a, involucrin immunoreactivity, and mRNA transcripts in the corneal epithelium of JNK1KO and C57BL/6 mice, but not in JNK2KO mice. Knockout of JNK2 prevented DS-induced increase in gelatinase and collagenase activity in the cornea.. The JNK2 protein appears to have an essential role in desiccation-induced corneal epithelial disease by stimulating production of MMP-1, MMP-9, and cornified envelope precursors. Clinical Relevance The JNK2 protein could be a novel therapeutic target in dry eye disease.

Topics: Animals; Corneal Diseases; Cornified Envelope Proline-Rich Proteins; Desiccation; Disease Models, Animal; Dry Eye Syndromes; Epithelium, Corneal; Fluorescent Dyes; Fluorophotometry; Matrix Metalloproteinase 1; Matrix Metalloproteinase 9; Mice; Mice, Inbred C57BL; Mice, Knockout; Microscopy, Confocal; Mitogen-Activated Protein Kinase 8; Mitogen-Activated Protein Kinase 9; Organic Chemicals; Permeability; Protein Precursors; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Stress, Physiological

The immunocytologic characteristics of two formalin-fixed, paraffin-embedded corneas from patients with the iridocorneal endothelial (ICE) syndrome and unaffected control corneas were studied. Binding of polyclonal antisera to Factor VIII, S-100 protein, involucrin, neuron specific enolase (NSE), and the lectins peanut agglutinin and Ulex europaeus agglutinin-1 was performed using the standard peroxidase-anti-peroxidase method. We detected reactive patterns of monoclonal antibodies to cytokeratins (34BE12 is a 56-58 kD mouse IgG reactive to stratified epithelia; Pkk1 is a 44-54 kD mouse IgG reactive to simple epithelia; and KL1 is a 55-57 kD mouse IgG reactive to epidermis and simple epithelia) using the standard avidin-biotin complex method. Staining properties were similar for the polyclonal antisera, lectins, NSE, and chromogranin in corneas with ICE syndrome and in the controls. However, the cytokeratins 34BE12, Pkk1, and KL1 were detected in the endothelium of the corneas with the ICE syndrome but not in the controls. These findings suggest that various cytokeratins are expressed in the corneal endothelium in the ICE syndrome that are not expressed in unaffected corneal endothelium.

Topics: Antibodies, Monoclonal; Corneal Diseases; Endothelium, Corneal; Factor VIII; Humans; Immunoenzyme Techniques; Iris Diseases; Keratins; Microscopy, Electron, Scanning; Protein Precursors; S100 Proteins; Syndrome