Abnormal maturation pathway of keratinocytes in psoriatic skin.
We compared the maturation pathway of normal and psoriatic epidermis using three different markers: (1) Involucrin, which is normally detected in the stratum granulosum in normal skin, was detected in all but the basal layer of involved psoriatic skin; (2) an antigen, recognized by the murine monoclonal antibody psi 3, was present in all but the basal layer of involved psoriatic skin but was absent from uninvolved and normal skin; (3) fibronectin, which normally localizes in the dermis and the epidermal-dermal junction, was also detected intra- and extracellularly in the psoriatic epidermis. These results indicate that the alterations in keratinocyte maturation found in psoriasis do not arise from a truncation of the normal maturation pathway but rather reflect the onset of an abnormal pathway of differentiation characterized by the expression of psi 3 antigen and fibronectin and the premature appearance of involucrin.
D000911:Antibodies, Monoclonal; D001485:Basement Membrane / Q000032:analysis; D002454:Cell Differentiation; D004817:Epidermis / Q000473:pathology; D005353:Fibronectins / Q000032:analysis; D005455:Fluorescent Antibody Technique; D006801:Humans; D011498:Protein Precursors / Q000032:analysis; D011565:Psoriasis / Q000378:metabolism / Q000473:pathology*; D012867:Skin / Q000032:analysis / Q000473:pathology*
D000911:Antibodies, Monoclonal; D005353:Fibronectins; D011498:Protein Precursors; C032253:involucrin