ELECTRON MICROSCOPY OF KERATIN LAYER STRIPPED HUMAN EPIDERMIS

[摘要] Electron microscopic study of human epidermis after removal of the horny layer by tape stripping reveals ultrastructur-al changes of the keratinocytes within 72 hr. as follows: The attachment of intracellular tonofilaments to the desmosomal attachment plaque is lost, and a subsequent perinuclear aggregation of separated tonofilaments occurs. There has so far been found no splitting of desmosomes into half-desmosomes. These desmosomes are retracted to 1 of the cells with a breakage of the other cell membrane. The retracted desmosomes can be found in the cytoplasm within imaginations of the cell membrane. Intercellular connections are lost and the cell surface forms free microvilli in the inlarged intercellular space. Regeneration of the keratin layer, as well as desmosomes in various stages of formation, are seen by 72 hr. after stripping. Desmosomes appear to be formed de novo rather than by repair of previous desmosomes. The implication of these findings in the pathogenesis of acantholytic diseases and in the use of stripped epidermis as a physiological tool is discussed briefly.