title: Leprosy: contribution of mast cells to epineurial collagenization.
abstract: 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.
authors.affiliation: Department of Pathology, School of Medicine, State University of Rio de Janeiro, Brazil. montagna@matrix.com.br
authors.forename: N Aparecida de Arantes
authors.initials: NA
authors.lastname: Montagna
authors.forename: M Leide Wan-del-Rey
authors.initials: ML
authors.lastname: de Oliveira
authors.forename: C A
authors.initials: CA
authors.lastname: Mandarim-de-Lacerda
authors.forename: L
authors.initials: L
authors.lastname: Chimelli
mesh_terms: 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
chemical_list: C509190:Tpsb2 protein, mouse; D003094:Collagen; D012697:Serine Endopeptidases; C509222:Tpsab1 protein, mouse; D053802:Tryptases