Leprosy: contribution of mast cells to epineurial collagenization.
BACKGROUND
Leprosy, a disease caused by Mycobacterium leprae, is an important health problem worldwide. It is responsible for an irreversible nerve damage in which fibrosis plays an important role. The existence of an interaction between mast cells and different fibrotic conditions has long been observed. Tryptase, the most abundant protein product of human mast cells, has been shown to be mitogenic for fibroblasts and to increase type I collagen production.


METHODS
In order to explore the possible relationship between tryptase-rich mast cells and nerve fibrosis in leprosy, we studied 24 sural nerve biopsies of patients with leprous neuropathy. Mast cells stained with mouse antihuman mast cell antitryptase clone AA1 as well as fibrosis, were quantitatively estimated in both epi- and endoneurial compartments.


RESULTS
There was a remarkable association between collagen increase and tryptase-rich mast cell density in the epineurium but not in the endoneurium of leprous nerves.


CONCLUSIONS
Since the epineurium in leprosy is type I collagen rich, the present findings support a tryptase-rich mast cell contribution to epineurial collagenization in leprosy through their tryptase secretion.
Montagna
N Aparecida de Arantes
NA
Department of Pathology, School of Medicine, State University of Rio de Janeiro, Brazil. montagna@matrix.com.br
de Oliveira
M Leide Wan-del-Rey
ML
Mandarim-de-Lacerda
C A
CA
Chimelli
L
L
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002452:Cell Count; D003094:Collagen / Q000378:metabolism; D005260:Female; D005355:Fibrosis; D006801:Humans; D007918:Leprosy / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D008407:Mast Cells / Q000201:enzymology*; D008875:Middle Aged; D012189:Retrospective Studies; D012697:Serine Endopeptidases / Q000378:metabolism*; D013497:Sural Nerve / Q000378:metabolism* / Q000473:pathology*; D053802:Tryptases
C509190:Tpsb2 protein, mouse; D003094:Collagen; D012697:Serine Endopeptidases; C509222:Tpsab1 protein, mouse; D053802:Tryptases