title: Cytokeratin expression in normal human bulbar conjunctiva obtained by impression cytology.
abstract: OBJECTIVE
  To document the cytokeratin expression patterns in the normal human conjunctival epithelium obtained directly from patients using impression cytology.
  
  
  METHODS
  Impression cytology specimens were obtained from normal volunteers using pure nitrocellulose membranes rather than cellulose acetate. The 31 volunteers of both sexes ranged in age from 18 to 79 years. Impression cytology specimens were analyzed for individual cytokeratins by either immunocytochemistry or electrophoresis with immunoblotting using a defined panel of monoclonal antibodies.
  
  
  RESULTS
  Using the corroborative methods of immunocytochemistry and electrophoresis with immunoblotting, cytokeratins characteristic of nonkeratinized, stratified (K4 and K13), simple (K8 and K19), and glandular epithelia (K7) were present in the superficial layer (s) of normal human conjunctiva. Cytokeratins typical of keratinized epithelia (K1, K2, and K10) and the keratinization-related proteins filaggrin and involucrin were not expressed in normal conjunctival epithelium.
  
  
  CONCLUSIONS
  The normal human conjunctiva demonstrates a unique cytokeratin expression pattern containing cytokeratins characteristic of nonkeratinized, stratified epithelia, as well as others more typical of a simple differentiation pattern, a glandular differentiation pattern, or both. These findings provide a foundation for examining changes in the cytokeratin expression pattern in diseased human conjunctival epithelium using impression cytology.
authors.affiliation: Department of Ophthalmology, Boston University Medical Center, Massachusetts, USA.
authors.forename: K L
authors.initials: KL
authors.lastname: Krenzer
authors.forename: T F
authors.initials: TF
authors.lastname: Freddo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal; D015415:Biomarkers; D015153:Blotting, Western; D003228:Conjunctiva / Q000166:cytology / Q000378:metabolism*; D003584:Cytological Techniques; D004591:Electrophoresis, Polyacrylamide Gel; D004848:Epithelium / Q000378:metabolism; D005260:Female; D000091344:Filaggrin Proteins; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007124:Immunoenzyme Techniques; D007381:Intermediate Filament Proteins / Q000096:biosynthesis; D007633:Keratins / Q000096:biosynthesis*; D008297:Male; D008875:Middle Aged; D011498:Protein Precursors / Q000096:biosynthesis
chemical_list: D000911:Antibodies, Monoclonal; D015415:Biomarkers; C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D007381:Intermediate Filament Proteins; D011498:Protein Precursors; C032253:involucrin; D007633:Keratins