Mast cells as part of problem? 2 more articles.

[Guest guest]

Great article , thanks for that and thank your mom. Another one to add to my list, *chuckle* I too have several on Mast cells.. I'll pass on a few here, although one refers to Lichen sclerosus ( 'I' still think same rose, just different name) haha.. same pain and generally same treatments *sigh*.. to me anyway.. and the other refers to Mast cells in skin diseases, histamines, and steroid use.

In fact I think it was this reasoning with the mast cells rather than the spirochetes that ruled out the borrelia burgdorfi connection that some earlier studies thought.

Warmest, Dee~ and thanks again..

Clin Exp Dermatol 1999 Nov;24(6):479-83 (ISSN: 0307-6938) Farrell AM; Millard PR; Schomberg KH; Wojnarowska FDepartment of Dermatology, Oxford Radcliffe Hospitals, UK.

Although there is evidence to support an autoimmune basis for lichen sclerosus, there have also been some studies which suggest an infective aetiology. These include reports of the presence of spirochaetal forms with Steiner silver stains and purplish coccoid forms with Fite stains. We have repeated these studies on vulval biopsies obtained from 16 patients with vulval lichen sclerosus. Using the Steiner silver method we found no evidence of spirochaetal forms in any of the specimens.

With the Fite stain we observed purple-staining coccoid forms within the dermis of 13 of the 16 lichen sclerosus specimens. However, these coccoid forms also stained strongly positive with toluidine blue, suggesting they were mast cell granules rather than micro-organisms. We were therefore unable to demonstrate evidence for an infective aetiology in vulval lichen sclerosus, although this cannot yet be excluded. Further work is also needed to understand the significance of mast cells in lichen sclerosus.

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2.

Cutaneous mast cell depletion results from topical corticosteroid usage.Lavker RM, Schechter NMThe effect of long-term topical application of corticosteroids on human cutaneous mast cells was examined. Two potent corticosteroids, clobetasol-17-propionate and fluocinonide, produced a greater than 85% decrease in histamine content over a 6-wk treatment period, whereas betamethasone valerate, a less potent corticosteroid, produced a 66% decrease.

Electron microscopic examination of the biopsies taken from sites after 6 wk of treatment indicate that the reduced levels of histamine were caused by the depletion of mast cells, as evidenced by: the inability to identify any cells representative of mast cells by detailed electron microscopy of the biopsies; and the marked acellularity around the vasculature where mast cells are certain to be detected. Histamine levels did not begin to decline until after 3 wk of corticosteroid treatment, indicating that corticosteroids are not immediately harmful to mast cells. Electron microscopic examination of biopsies taken at the beginning of treatment and 1 wk later showed normal-appearing mast cells, whereas at 3 wk, a small population of mast cells was detected with features usually associated with degenerating or dying cells. These observations suggest that protracted application of corticosteroids to skin is toxic to mast cells. After discontinuation of treatment, the drug-related atrophy associated with chronic application of potent corticosteroids to skin is rapidly reversed, and skin structure returns to near normal by 14 days. Over this time period, however, histamine levels did not increase and mature mast cells could not be observed by electron microscopy. At 14 days post-steroid treatment, the first signs of cells containing sparse amounts of granules having the characteristics of mast cell granules were seen. We interpret this to represent new mast cells beginning to mature in the skin. By 3 mo, histamine levels returned to normal, demonstrating the reversibility of the steroid-induced mast cell depletion. The studies presented here establish the deleterious effects of long-term topical corticosteroid treatment on cutaneous mast cells, and begin to establish a system in which the development of mast cells in tissue can be investigated.PMID: 4031494