T regulatory cells and plasmocytoid dentritic cells in hansen disease: a new insight into pathogenesis?
Am J Dermatopathol
; 32(3): 251-256, 2010 May.
Article
em En
| MEDLINE
| ID: mdl-20075708
ABSTRACT
Leprosy is characterized by spectrum of histologically different granulomatous skin lesions that reflects the patient's immune response to Mycobacterium leprae. Presence, frequency, and distribution of both CD4+ CD25+ FoxP3+ T regulatory cells (T-regs) and CD123+ plasmacytoid dendritic cells in leprosy have never been investigated. We performed a retrospective immunohistochemical study on 20 cases of leprosy [tuberculoid tuberculoid (TT) 1 patient; borderline tuberculoid (BT) 3 patients; borderline lepromatous (BL) 5 patients; lepromatous lepromatous (LL) 5 patients; borderline borderline in reversal reaction (BB-RR) 1 patient; BT-RR 2 patients; and erythema nodosum leprosum (ENL) 3 patients]. FoxP3-positive cells were present in 95% of the cases with an average density of 2.9% of the infiltrate. Their distribution was not related to granulomatous structures or special locations. There was no statistical difference of FoxP3 expression between TT, BT, BL, and LL, whereas a statistical significant increment (P = 0.042) was observed in patients affected by reversal leprosy reactions (BT-RR and BB-RR) compared with patients affected by ENL and patients with nonreactional disease forms (BL, LL, BT, TT). CD123 expression was not observed in any of the biopsy specimens evaluated; with the exception of 2 cases of ENL, in which a focal positivity for CD123 was observed. Our results show that plasmacytoid dendritic cells are not involved in the immune response against M. leprae while T-regs are present in leprosy skin lesions. These data raise the question if T-regs have a pathogenetic role in HD as previously demonstrated in Leishmania major and Mycobacterium tuberculosis.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Células Dendríticas
/
Linfócitos T Reguladores
/
Hanseníase
Tipo de estudo:
Etiology_studies
/
Observational_studies
Limite:
Adult
/
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Am J Dermatopathol
Ano de publicação:
2010
Tipo de documento:
Article