IMMUNOHISTOCHEMICAL LOCALIZATION AND QUANTIFICATION OF DESMOPLAKIN-I AND DESMOPLAKIN-II AND KERATIN-1 AND KERATIN-19 IN PLASTIC-EMBEDDED SECTIONS OF HUMAN GINGIVA

We developed immunohistochemical and image analytical techniques to localize and quantify keratins and desmoplakins in sections of plastic-embedded human gingiva. Acetone fixation followed by plastic embedding of gingiva provided excellent morphology and permitted immunohistochemical detection of keratins 1 and 19 and desmoplakins I & II after 2.5-min trypsin digestion. Quantitative image analysis demonstrated that different volume densities of staining of each marker were associated with specific epithelial strata. Keratin 1 stained most heavily in granular strata, followed by corneal and spinous strata; keratin 19 stained most strongly in the basal layer; desmoplakins I & II stained most strongly in the granular and corneal strata. These findings confirm that variations of keratin and desmoplakin expression in these epithelia are associated with regional patterns of epithelial differentiation.