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Pathophysiologic events in certain types of epidermolysis bullosa
II. Special Lectures
318
PATHOPHYSIOLOGICEVENTS IN CERTAIN TYPES OF EPIDERMOLYSIS
ALLERGY ANDATOPICECZEMA(AE)
BULLOSA
A. KRONBERGER,
E. VCGES,
R. GRYMES,
E. BAUER
Department of Dermatology, Stanford University School of Medicine, Stanford, California USA 94305 Recessive dys!rc?hic cpitiormolysis bullosa (RDEB) is characterized by blistering with subsequent scarring, digital fusion and flexural contractures. Ultrastructural analysis of the skin reveals an absence and/or abnormal appearance to the anchoring fibril comp!ax. In addition, there is destruction of interstitial collagen in the papillary dermis. Two major hypotheses far the pathogenssis of this form of EB have been explored: decreased expression of type VII collagen. the major structural component of the anchoring fibril complex and increased expression of collagenase. Certain studies indicate that expression of type VII collagen is abnormal in RDEE, while others suggest that collagenase expression is enhanced at least in some patients. Cultured fibroblasts may display elevated constitutive synthesis of collagenase and be further stimulated to synthesize collagenase by interleukin-1 and plateletderived growth factor. In vitro type VII collagen is cleaved by both intersthial collagenase and gelatinase. These findings suggest that both altered expression of type VII collagen and its degradation by collagenase may be important in the connez:ive tissue destruction which characterizes RDEE.
PROF. DR. NED. DR. PHIL. JOHANNES RING Universitats-Hautklinik Eppendorf. Martinistr. Hamburg20, West-Germany
52. 2000
While the pathomechanisms of allergic respiratory diseases are well established, the role of allergic reactions in Of special atopic eczema is still a matter of controversy. interest is the relation between IgE (Type I) and delayed type hypersensitivity (Type IV) reactions in AE. Allergic contact dermatitis does not seem to be decresed in AE Recent contrary to some earlier studies in the literature. investigations focusing on I&receptors on Langerhans cells as well as on the role of IgE antibodies have shown increasina evidence for a oathoohysiolonical role of InEmediated reactions in at l&t. bnk subgroup of patients diagnostic and therapeutic with AE. This is of considerable importance, e. g. with regard to allergen avoidance In patients strategies wtih diets or environmental contol. with AE dermatolgists should not only treat the inflammatory skin symptoms hut be engaged in trying to find causal triggering factors.
ULTICARIAPIGMENTOSA: SYSTEMICEVALOATION ANDSUCCESSFUL TREATMENT WITHTOPICALSTEROIDS.
ONTOGENY OF HUMAN MERKELCELL
GERALII s. IAzAHus, M.D., CYNTHIAwzzo. 8. D. ANDNORNAN SCHECHTER. PH.D., Department of Dermatology, University of Pennsylvania, Philadelphia, Pennsylvania
and YUTAKA NARISAWA KENHASHIMOTO Department of Dermatology, Wayne State University School of Medicine, 540 E. Canfield, Detroit, MI 48201
Nine patients with adult onset urticaria pigmentosa were studied. Seven of the 9 patients had increased mast cells in the bone marrow biopsy. Liver-spleen scans revealed a shift of colloid uptake from liver to spleen in 4 patients. Urinary histamine metabolites correlated with bone marrow involvement but not with other paramaters. Psycho”eurological testing revealed significant deviation from the norm. Al1 9 patients were treated with .05%betamethasone dipropionate ointment under occlusion to one half of the body nightly for 6 weeks, with excellent response in 1 patients. Two patients developed transient abnormalities in HPAaxis suppression, bath of whomwed the medication improperly. Systemic involvement is freqnent in patients with cutaneous mast cell disease and lesions can be safely and effectively treated with topical steroids in motivated patients.
Investigation on human Merkel cell has made great progress with the discovery of several innnunostain-positive substances in this cell type. These are simple epithelial keratins, epithelial membrane antigen, chromogranin etc. On the other hand, cutaneous nerveendings could also be demonstrated by immunostain and a double stain technique can visualize both Merkel cells and cutaneous nerves in the same tissue section. In this Study we shall present fetal development data of Merkel cells suggesting that 1. Merkel cells originate in the epidermis, 2. when Merkel cells begin to drop into the mesenthyme, nerve endings are not present at dermal-epidermal junction and 3. nerve-Merkel cell complex is formed in the upper dermis where future nerve plexus will develop. Dermal Merkel cells disappear by losing their markers after a full development of nerve networks. It seems that dermal Merkel cells play an important role in the development of nerve plexus in the upper dermis.
318
PATHOPHYSIOLOGICEVENTS IN CERTAIN TYPES OF EPIDERMOLYSIS
ALLERGY ANDATOPICECZEMA(AE)
BULLOSA
A. KRONBERGER,
E. VCGES,
R. GRYMES,
E. BAUER
Department of Dermatology, Stanford University School of Medicine, Stanford, California USA 94305 Recessive dys!rc?hic cpitiormolysis bullosa (RDEB) is characterized by blistering with subsequent scarring, digital fusion and flexural contractures. Ultrastructural analysis of the skin reveals an absence and/or abnormal appearance to the anchoring fibril comp!ax. In addition, there is destruction of interstitial collagen in the papillary dermis. Two major hypotheses far the pathogenssis of this form of EB have been explored: decreased expression of type VII collagen. the major structural component of the anchoring fibril complex and increased expression of collagenase. Certain studies indicate that expression of type VII collagen is abnormal in RDEE, while others suggest that collagenase expression is enhanced at least in some patients. Cultured fibroblasts may display elevated constitutive synthesis of collagenase and be further stimulated to synthesize collagenase by interleukin-1 and plateletderived growth factor. In vitro type VII collagen is cleaved by both intersthial collagenase and gelatinase. These findings suggest that both altered expression of type VII collagen and its degradation by collagenase may be important in the connez:ive tissue destruction which characterizes RDEE.
PROF. DR. NED. DR. PHIL. JOHANNES RING Universitats-Hautklinik Eppendorf. Martinistr. Hamburg20, West-Germany
52. 2000
While the pathomechanisms of allergic respiratory diseases are well established, the role of allergic reactions in Of special atopic eczema is still a matter of controversy. interest is the relation between IgE (Type I) and delayed type hypersensitivity (Type IV) reactions in AE. Allergic contact dermatitis does not seem to be decresed in AE Recent contrary to some earlier studies in the literature. investigations focusing on I&receptors on Langerhans cells as well as on the role of IgE antibodies have shown increasina evidence for a oathoohysiolonical role of InEmediated reactions in at l&t. bnk subgroup of patients diagnostic and therapeutic with AE. This is of considerable importance, e. g. with regard to allergen avoidance In patients strategies wtih diets or environmental contol. with AE dermatolgists should not only treat the inflammatory skin symptoms hut be engaged in trying to find causal triggering factors.
ULTICARIAPIGMENTOSA: SYSTEMICEVALOATION ANDSUCCESSFUL TREATMENT WITHTOPICALSTEROIDS.
ONTOGENY OF HUMAN MERKELCELL
GERALII s. IAzAHus, M.D., CYNTHIAwzzo. 8. D. ANDNORNAN SCHECHTER. PH.D., Department of Dermatology, University of Pennsylvania, Philadelphia, Pennsylvania
and YUTAKA NARISAWA KENHASHIMOTO Department of Dermatology, Wayne State University School of Medicine, 540 E. Canfield, Detroit, MI 48201
Nine patients with adult onset urticaria pigmentosa were studied. Seven of the 9 patients had increased mast cells in the bone marrow biopsy. Liver-spleen scans revealed a shift of colloid uptake from liver to spleen in 4 patients. Urinary histamine metabolites correlated with bone marrow involvement but not with other paramaters. Psycho”eurological testing revealed significant deviation from the norm. Al1 9 patients were treated with .05%betamethasone dipropionate ointment under occlusion to one half of the body nightly for 6 weeks, with excellent response in 1 patients. Two patients developed transient abnormalities in HPAaxis suppression, bath of whomwed the medication improperly. Systemic involvement is freqnent in patients with cutaneous mast cell disease and lesions can be safely and effectively treated with topical steroids in motivated patients.
Investigation on human Merkel cell has made great progress with the discovery of several innnunostain-positive substances in this cell type. These are simple epithelial keratins, epithelial membrane antigen, chromogranin etc. On the other hand, cutaneous nerveendings could also be demonstrated by immunostain and a double stain technique can visualize both Merkel cells and cutaneous nerves in the same tissue section. In this Study we shall present fetal development data of Merkel cells suggesting that 1. Merkel cells originate in the epidermis, 2. when Merkel cells begin to drop into the mesenthyme, nerve endings are not present at dermal-epidermal junction and 3. nerve-Merkel cell complex is formed in the upper dermis where future nerve plexus will develop. Dermal Merkel cells disappear by losing their markers after a full development of nerve networks. It seems that dermal Merkel cells play an important role in the development of nerve plexus in the upper dermis.