Increased hepcidin expression in multibacillary leprosy

Iron is essential for all organisms and its availability can control the growth of microorganisms; therefore, we examined the role of iron metabolism in multibacillary (MB) leprosy, focusing on the involvement of hepcidin. Erythrograms, iron metabolism parameters, pro-inflammatory cytokines and urinary hepcidin levels were evaluated in patients with MB and matched control subjects. Hepcidin expression in MB lesions was evaluated by quantitative polymerase chain reaction. The expression of ferroportin and hepcidin was evaluated by immunofluorescence in paucibacillary and MB lesions. Analysis of hepcidin protein levels in urine and of hepcidin mRNA and protein levels in leprosy lesions and skin biopsies from healthy control subjects showed elevated hepcidin levels in MB patients. Decreases in haematologic parameters and total iron binding capacity were observed in patients with MB leprosy. Moreover, interleukin-1 beta, ferritin, soluble transferrin receptor and soluble transferrin receptor/log ferritin index values were increased in leprosy patients. Hepcidin was elevated in lepromatous lesions, whereas ferroportin was more abundant in tuberculoid lesions. In addition, hepcidin and ferroportin were not colocalised in the biopsies from leprosy lesions. Anaemia was not commonly observed in patients with MB; however, the observed changes in haematologic parameters indicating altered iron metabolism appeared to result from a mixture of anaemia of inflammation and iron deficiency. Thus, iron sequestration inside host cells might play a role in leprosy by providing an optimal environment for the bacillus.CNPq [401012/2005-0]CNPqFundacao Paulista contra a HanseniaseFundacao Paulista contra a Hanseniase [095

Polymorphisms in the TGFB1 and IL2RA genes are associated with clinical forms of leprosy in Brazilian population

BACKGROUND Leprosy is a chronic infectious disease caused by Mycobacterium leprae, and compromises the skin and peripheral nerves. This disease has been classified as multibacillary (MB) or paucibacillary (PB) depending on the host immune response. Genetic epidemiology studies in leprosy have shown the influence of human genetic components on the disease outcomes. OBJECTIVES We conducted an association study for IL2RA and TGFB1 genes with clinical forms of leprosy based on two case-control samples. These genes encode important molecules for the immunosuppressive activity of Treg cells and present differential expressions according to the clinical forms of leprosy. Furthermore, IL2RA is a positional candidate gene because it is located near the 10p13 chromosome region, presenting a linkage peak for PB leprosy. METHODS A total of 885 leprosy cases were included in the study; 406 cases from Rondonópolis County (start population), a hyperendemic region for leprosy in Brazil, and 479 cases from São Paulo state (replication population), which has lower epidemiological indexes for the disease. We tested 11 polymorphisms in the IL2RA gene and the missense variant rs1800470 in the TGFB1 gene. FINDINGS The AA genotype of rs2386841 in IL2RA was associated with the PB form in the start population. The AA genotype of rs1800470 in TGFB1 was associated with the MB form in the start population, and this association was confirmed for the replication population. MAIN CONCLUSIONS We demonstrated, for the first time, an association data with the PB form for a gene located on chromosome 10. In addition, we reported the association of TGFB1 gene with the MB form. Our results place these genes as candidates for validation and replication studies in leprosy polarisation

Activation and cytokine profile of monocyte derived dendritic cells in leprosy: in vitro stimulation by sonicated Mycobacterium leprae induces decreased level of IL-12p70 in lepromatous leprosy

Dendritic cells (DCs) play a pivotal role in the connection of innate and adaptive immunity of hosts to mycobacterial infection. Studies on the interaction of monocyte-derived DCs (MO-DCs) using Mycobacterium leprae in leprosy patients are rare. The present study demonstrated that the differentiation of MOs to DCs was similar in all forms of leprosy compared to normal healthy individuals. In vitro stimulation of immature MO-DCs with sonicated M. leprae induced variable degrees of DC maturation as determined by the increased expression of HLA-DR, CD40, CD80 and CD86, but not CD83, in all studied groups. The production of different cytokines by the MO-DCs appeared similar in all of the studied groups under similar conditions. However, the production of interleukin (IL)-12p70 by MO-DCs from lepromatous (LL) leprosy patients after in vitro stimulation with M. leprae was lower than tuberculoid leprosy patients and healthy individuals, even after CD40 ligation with CD40 ligand-transfected cells. The present cumulative findings suggest that the MO-DCs of LL patients are generally a weak producer of IL-12p70 despite the moderate activating properties ofM. leprae. These results may explain the poor M. leprae-specific cell-mediated immunity in the LL type of lepros