Lacueva L, Hausmann G, Sheppers C, Martí LRM, Ferrando J

Language: Spanish
References: 10
Page: 101-105
PDF size: 250.32 Kb.

ABSTRACT

The complement system is a group of 28 plasma proteins that interact through a well-defined sequence of protein activation cascade. The final products of this cascade are the membrane attack complex (MAC or C5b-9) and proteins derived from the fragmentation of complement components. Deposits of MAC in skin have been detected in various diseases of autoimmune origin, such as cutaneous lupus erythematosus (DLE), pemphigus, dermatomyositis and cutaneous vasculitis.
Material and methods: Nine biopsies were performed in lateral borders of patches of alopecia areta (AA) six biopsies were performed in normal hairy scalp skin and one biopsy in affected scalp of a patient with DLE. For immunostaining we use a biotin streptavidin immunodetection system (BioGenex, USA) and monoclonal antihuman C5b-9 antibodies (Dakopatts, Denmarck).
Results: In 8 out of 9 AA cases we detected MAC deposits in the BMZ of many follicles, mainly in the lower portion of the hair follicle and in the bulge area.. In the healthy controls 2 out of 6 biopsies showed MAC deposits in the BMZ near to the sebaceous gland. In the DLE patient we found dense MAC deposits in the BMZ and in the hair follicles.
Conclusion: MAC deposits are more frequent in the AA areas that in normal skin, but less dense that in DLE. Probably the MAC and the complement system play a role in the pathophysiology of the AA as well as in the normal development of follicle cycle.

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