Untersuchungen über die celluläre zusammensetzung des lichen ruber planus-infiltrates

Lichen nitidus: a histologic and electron microscopic study

A lesion of lichen nitidus in a 53-year-old man was examined by histology and electron microscopy. The histology showed typical features. The electron microscopy revealed primary changes in hydropic degeneration of basal cells which possibly indicated severe edema between the basal keratinocytes and in the subepidermal area. The basal keratinocytes themselves were not particularly altered, except for clustered micro-vacuolar structures in a small portion of the peripheral cytoplasm. In one of the eight blocks observed, the cytoplasmic process of a mast cell was found between the basal keratinocytes, indicating that mast cells may possibly infiltrate the epidermis in lichen nitidus. Scattered mast cells in the dermis were also noted. Thus primary pathologic changes of lichen nitidus may be induced by severe edema, which was accompanied by inflammatory cells including mast cells, in the region of the dermal-epidermal junction.

Lichen planus: review and update on pathogenesis

Lichen planus (LP) is a common oral disorder which may represent the manifestation of a mucosal reaction to a variety of aetiological factors. Of the many immunological changes described in LP several may be epiphenomena although a cell-mediated immune response to unidentified antigens or antigenic changes clearly is involved. Associations with drugs or systemic disorders are well-defined in some patients but may, in others, be aleatoric. Finally, the prognosis of oral LP not only differs from that of cutaneous LP but there is little doubt that in a few instances LP is a premalignant condition.

Glucocorticosteroids and oral medicine

The article deals with the use of glucocorticosteroids in the treatment of the oral manifestations of Systemic Lupus Erythematosus (SLE), Discoid Lupus Erythematosus (DLE), Rheumatoid Arthritis (RA) in the temporomandibular joint, Pemphigus Vulgaris, Pemphigoid, Erythema Multiforme Exudativum (EME), Lichen Planus (LP), and Recurrent Aphthous Ulcerations (RAU). The benefit from steroids is discussed on the basis of current knowledge of etiology and pathogenesis of the various disorders. All of them are characterized by inflammation which appears secondary to a hypersensitivity reaction against autocomponents. Glucocorticoids do not interfere with the primary disease mechanisms. But it is concluded from the literature, that because of anti-inflammatory and immunosuppressive effects of the hormones, it seems reasonable to profit from steroids as palliatives in acute phases of the diseases and/or as long-term suppressors of the general host defense.

Changes in carbohydrate expression of lichen planus affected oral epithelial cell membranes

The purpose of the present study was to examine possible epithelial cell membrane changes in lichen planus affected oral mucosa by the use of the lectins concanavalin-A and ricinus communis agglutinin fraction I. It was shown that these lectins in contrast to what was found in normal epithelium do not bind to the cell membranes of basal cells of lichen planus affected epithelium. The lack of binding of lectins suggests changes in exposed carbohydrates at the surfaces of the cells. The findings may support the hypothesis of antigenic changes in the lichen planus affected epithelium.

Oral photochemotherapy in the treatment of lichen planus (LP). Clinical results, histological and ultrastructural observations

Seven patients with diffuse lichen planus were treated with oral photochemotherapy. Remission was effected in 6 cases. The only failure may be attributable to a low UVA dose. Histological examination after treatment showed disappearance of the superficial dermal lymphocytic infiltrate. Ultrastructural study revealed nuclear alterations of keratinocytes and nuclear and cytoplasmic changes in superficial dermal cells. Various theories concerning the mode of action of photochemotherapy in lichen planus are discussed in the light of these observations.

Cell proliferation in the Lichen planus infiltrate. Investigations by light- and electron-microscopic autoradiography

In seven patients suffering from lichen planus (LP) light- and electron-microscopic 3H-thymidine (3HT) labeling studies were performed and the following results were obtained. 1. Using the light-microscope, a large number of 3HT labeled cells can be observed in the dermal infiltrate of LP. Most of the labeled nuclei belong to mononuclear, 'round cells' while isolated endothelial cells, fibroblasts, histiocytes and mast cells could be found labeled. 2. The mean labeling index of 'round cells' in our patients was 4.27 +/- 1.57%. 3. The evaluation of the electron microscopic autoradiographs showed that, as far as 'round' cells were concerned, exclusively nuclei of cells showing the morphological criteria of stimulated lymphocytes were labeled. These findings support the view that in LP, as in allergic contact dermatitis, a high proliferative activity of lymphocytes takes place.

Cell-mediated immunity in lichen planus. In vitro tests with extracts from lichen planus lesions

Extracts were prepared from lichen planus lesions and from healthy epidermis of normal controls. Their effect on the migration and lymphocyte transformation of autologous leukocytes was studied. On the whole, the ranges of variation and mean values of the autologous leukocyte migration indices obtained in the presence of LP skin extract or sediment from 10 LP patients did not significantly differ from those recorded in the presence of similar extracts prepared from the epidermis of 12 normal controls. Two assays with LP skin sediment antigen and one assay with LP supernatant antigen, however, fell within the range of significant changes in migration. Lymphocyte transformation, as indicated by increased thymidine uptake, was significantly stimulated by LP epidermis in 1 case of 5 LP patients. Extracts from normal epidermis did not affect the transformation of autologous lymphocytes. The phytohemagglutinin response of lymphocytes from LP patients was the same as that of normal controls. The results do not indicate that cell-mediated immunity toward epidermal antigens play any significant role in the etiopathogenesis of lichen planus.

The inflammatory infiltrate in lichen planus lesions. An autoradiographic and ultrastructural study

The labeling index of the infiltrate of oral lichen planus lesions was significantly greater than that of normal mucosa, and its labeling activity redistributed, as determined by in vitro autoradiography. An electron microscopic examination of the infiltrate of lichen planus lesions of oral mucosa and skin supported the concept that the lichen planus infiltrate represents a cell mediated immune response in which T lymphocytes and macrophages are predominant.

[Immunological investigations in lichen planus patients (author's transl)]

30 patients suffering from generalized lichen planus (= L.p.) have been examined by the following methods in order to more precise information regarding their immune-status: 1. Quantitative determination of immuno-globulins including complement fraction (beta 1C/A) 2. Intracutaneous tests with recall-antigens 3. Investigation of cutaneous sensitivity to DNCB 4. Lymphocytemigrationinhibition- and Lymphocytetransformationstests. The results obtained were not statistically significant when comparing the results of this investigation in patients suffering from L.p. with the control group. Therefore, the theory that immunological processes are the basis of these occurences is still under discussion. Further studies applying more specific methods should be conducted in order to clarify this problem.

Ultrastructure of inborm errors of keratinization. VII. Porokeratosis Mibelli and disseminated superficial actinic porokeratosis

The cornoid lamella and the underlying epidermis were studied by electron microscopy on specimens biopsied from 2 patients with porokeratosis Mibelli and 1 patient with actinic porokeratosis. Findings on the two types of porokeratoses are essentially the same. The cornoid lamella was composed chiefly of extremely irregular dark cells and a few numbers of dyskeratotic cells. Both cells retained a nuclear remnant and many other degraded organelles. The epidermal cells just beneath the cornoid lamella simultaneously demonstrated productive and degenerative signs. Some of these epidermal cells underwent dyskeratosis and appeared as corps ronds-like bodies in the granular layer. Two contradictory phenomena should be attributed to the pathogenesis of cornoid lamella. In the cornoid lamella above the sweat pore microvilli-structures were found.