ULTRASTRUCTURE OF EPIDERMIS IN LICHEN RUBER PLANUS AS REVEALED BY ELECTRON MICROSCOPY .2. CYTOPLASM AND NUCLEUS IN CERTAIN BASAL AND SPINOUS CELLS

Throughout the nuclear matrix a large number of distinctly visible fibrils is observed in certain basal and spinous cells in lichen ruber planus. With respect to ultrastructure, stainability, and arrangement they accord with the cytoplasmic fibrils, which, however, are rather few in number. In the spinous cells the cytoplasmic and nuclear fibrils show indications of a speckled pattern. Vacuolar formations of similar appearance are distinguished in the cytoplasm and nucleus. In the chromatin areas and in the nuclear matrix particles occur which, in size, ultrastructure, and stainability, are similar to the cytoplasmic ribosomes. In the perinuclear zone small, irregularly outlined areas occur. These show a pattern similar to that of the chromatin areas of the nucleus. Close to the areas in the perinuclear zone, to the chromatin areas, and isolated in the nuclear matrix, particles of similar appearance are observed. The rather uniformly opaque particles associated with the faintly stainable karyoplasmic filaments have a diameter of 70-120 Å. © 1969 Academic Press, Inc.