02823nas a2200445   4500000000100000008004100001260001300042653001000055653000900065653001500074653002000089653001100109653003500120653001100155653002800166653004100194653001200235653000900247653001600256653002600272653003000298653001600328100001400344700001200358700002400370700001400394700001400408700001800422700001600440700001600456700001400472700001600486700001100502700001400513245010800527300001000635490000700645520171100652022001402363       2010                            d  c2010 May10aAdult10aAged10aBiomarkers10aDendritic Cells10aFemale10aForkhead Transcription Factors10aHumans10aImmunoenzyme Techniques10aInterleukin-3 Receptor alpha Subunit10aleprosy10aMale10aMiddle Aged10aRetrospective Studies10aT-Lymphocytes, Regulatory10aYoung Adult1 aMassone C1 aNunzi E1 aRibeiro-Rodrigues R1 aTalhari C1 aTalhari S1 aSchettini APM1 aParente JNT1 aBrunasso AM1 aPuntoni M1 aClapasson A1 aNoto S1 aCerroni L00aT regulatory cells and plasmocytoid dentritic cells in hansen disease: a new insight into pathogenesis?  a251-60 v323 a<p>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.</p>  a1533-0311