Focal gaps in the basement membrane of involved and uninvolved skin of vitiligo: are they normal?
It has been suggested that, in vitiligo, the structural abnormalities may not be restricted to melanocytes alone, but also to keratinocytes of involved and uninvolved skin. Focal gaps in the vitiligo epidermal basement membrane have been furthermore interpreted as evidence of extramelanocyte alterations. To understand the occurrence of the gaps we undertook a study to establish which cells are related to them. Immunofluorescence and immunoperoxidase techniques were used to visualize, in involved, uninvolved, and control skin, the basement membrane, melanocytes, and Merkel cells. Double staining was performed with fluorescein-coupled anti-collagen IV antibodies and rhodamin-coupled antibodies against Nicein (GB3), a hemidesmosome component. Propidium iodide staining was used to detect infiltrating lymphocytes. The basement membrane structure was always found to be intact and unaltered. Absence of staining in areas of uninvolved skin was related to the presence of Merkel cells, melanocytes, and infiltrating lymphocytes. Gaps in the epidermal basement membrane are thus due to lack of staining caused by the presence of immigrant cells.
Bose
S K
SK
Pasteur Hospital, University of Nice.
Ortonne
J P
JP
D000293:Adolescent; D000328:Adult; D001485:Basement Membrane / Q000166:cytology; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007124:Immunoenzyme Techniques; D015603:Keratinocytes / Q000473:pathology; D008297:Male; D008544:Melanocytes / Q000473:pathology; D008875:Middle Aged; D012867:Skin / Q000166:cytology*; D014820:Vitiligo / Q000473:pathology*