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1.
J Peripher Nerv Syst ; 12(3): 195-204, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17868246

RESUMEN

Matrix metalloproteinases (MMPs) and tumor necrosis factor alpha (TNF-alpha) play important and related roles in the pathogenesis of nerve injury. MMP-dependent and TNF-alpha-dependent processes of neurodegeneration, such as blood-nerve breakdown and immune cell recruitment, are characteristic of leprosy nerve damage. Our work has contributed to the understanding of the role of cytokines in the process, but the role of MMPs in the pathogenesis of neuritic leprosy has not been investigated. This study analyzed the changes in mRNA expression and immunodistribution of MMP-2, MMP-9, TNF-alpha-converting enzyme (TACE), TNF-alpha in nerves of 27 pure neuritic leprosy (PNL) patients, both acid-fast bacilli positive (AFB(+)) and acid-fast bacilli negative (AFB(-)), and 8 non-leprosy patients with control peripheral neuropathic conditions. MMP-2, MMP-9, and TNF-alpha mRNA expression was significantly induced in the AFB(-) relative to the AFB(+) neuritic leprosy group and nonlepritic controls; TACE levels were also elevated in the AFB(-) group, but this change was not statistically significant. Immunoreactive profiles for TNF-alpha and MMPs demonstrated strong reactivity of myelinated axons, infiltrating macrophages, Schwann cells, endothelial cells, and perineurial cells in neuritic leprosy biopsies. This study provides the evidence of the involvement of MMPs in the pathogenesis of PNL neuropathy.


Asunto(s)
Proteínas ADAM/biosíntesis , Lepra/metabolismo , Metaloproteinasa 2 de la Matriz/biosíntesis , Metaloproteinasa 9 de la Matriz/biosíntesis , Nervios Periféricos/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesis , Proteína ADAM17 , Adulto , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Inmunohistoquímica , Lepra/enzimología , Masculino , Persona de Mediana Edad , Nervios Periféricos/enzimología , ARN/genética , ARN/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
2.
Microb Pathog ; 43(5-6): 249-54, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17624714

RESUMEN

Proteases are commonly involved in bacterial pathogenesis and their inhibition has represented a successful therapeutic approach to treat infectious diseases. However, there is little information on the role of proteases in the pathogenesis of Mycobacteria. Five of these genes, three coding for putative secreted proteases, were selected in the present study to investigate their expression in Mycobacterium leprae isolated from skin biopsies of multibacillary leprosy patients. Via nested-PCR, it was demonstrated that mycP1 or ML0041, htrA2 or ML0176, htrA4 or ML2659, gcp or ML0379 and clpC or ML0235 are transcribed in vivo during the course of human infection. Moreover, the expression of Gcp in leprosy lesions was further confirmed by immunohistochemistry using a specific hyperimmune serum. This observation reinforces the potential role of mycobacterial proteases in the context of leprosy pathogenesis.


Asunto(s)
Lepra/enzimología , Mycobacterium leprae/enzimología , Péptido Hidrolasas/metabolismo , Animales , Anticuerpos Antibacterianos , Antígenos Bacterianos/metabolismo , Regulación Bacteriana de la Expresión Génica/genética , Regulación Bacteriana de la Expresión Génica/fisiología , Humanos , Lepra/metabolismo , Ratones , Ratones Endogámicos BALB C , Mycobacterium leprae/genética , Mycobacterium leprae/patogenicidad , Piel/microbiología
3.
J Immunol ; 173(6): 4120-9, 2004 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-15356162

RESUMEN

T cell production of IFN-gamma contributes to host defense against infection by intracellular pathogens, including mycobacteria. Lepromatous leprosy, the disseminated form of infection caused by Mycobacterium leprae, is characterized by loss of cellular response against the pathogen and diminished Th1 cytokine production. Relieving bacterial burden in Ag-unresponsive patients might be achieved through alternative receptors that stimulate IFN-gamma production. We have previously shown that ligation of signaling lymphocytic activation molecule (SLAM) enhances IFN-gamma in mycobacterial infection; therefore, we investigated molecular pathways leading from SLAM activation to IFN-gamma production in human leprosy. The expression of the SLAM-associated protein (an inhibitory factor for IFN-gamma induction) on M. leprae-stimulated cells from leprosy patients was inversely correlated to IFN-gamma production. However, SLAM ligation or exposure of cells from lepromatous patients to a proinflammatory microenvironment down-regulated SLAM-associated protein expression. Moreover, SLAM activation induced a sequence of signaling proteins, including activation of the NF-kappaB complex, phosphorylation of Stat1, and induction of T-bet expression, resulting in the promotion of IFN-gamma production, a pathway that remains quiescent in response to Ag in lepromatous patients. Therefore, our findings reveal a cascade of molecular events during signaling through SLAM in leprosy that cooperate to induce IFN-gamma production and strongly suggest that SLAM might be a focal point for therapeutic modulation of T cell cytokine responses in diseases characterized by dysfunctional Th2 responses.


Asunto(s)
Adyuvantes Inmunológicos/fisiología , Glicoproteínas/fisiología , Inmunoglobulinas/fisiología , Líquido Intracelular/inmunología , Líquido Intracelular/microbiología , Péptidos y Proteínas de Señalización Intracelular , Mycobacterium leprae/inmunología , Transducción de Señal/inmunología , Células TH1/inmunología , Células TH1/metabolismo , Adyuvantes Inmunológicos/metabolismo , Antígenos CD , Proteínas Portadoras/antagonistas & inhibidores , Proteínas Portadoras/biosíntesis , Células Cultivadas , Citocinas/fisiología , Proteínas de Unión al ADN/metabolismo , Regulación hacia Abajo/inmunología , Glicoproteínas/inmunología , Glicoproteínas/metabolismo , Humanos , Inmunoglobulinas/inmunología , Inmunoglobulinas/metabolismo , Líquido Intracelular/enzimología , Líquido Intracelular/metabolismo , Lepra/enzimología , Lepra/inmunología , Lepra/metabolismo , Ligandos , Activación de Linfocitos/inmunología , FN-kappa B/metabolismo , Transporte de Proteínas/inmunología , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-fyn , Receptores de Superficie Celular , Factor de Transcripción STAT1 , Índice de Severidad de la Enfermedad , Proteína Asociada a la Molécula de Señalización de la Activación Linfocitaria , Miembro 1 de la Familia de Moléculas Señalizadoras de la Activación Linfocitaria , Proteínas de Dominio T Box , Células TH1/enzimología , Células TH1/microbiología , Transactivadores/metabolismo , Factores de Transcripción/biosíntesis
8.
s.l; s.n; 1992. 4 p. tab.
No convencional en Inglés | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1236522
9.
s.l; s.n; 1992. 4 p.
No convencional en Inglés | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1236532
10.
s.l; s.n; 1992. 7 p. tab.
No convencional en Inglés | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1236601
12.
Indian J Lepr ; 57(2): 282-7, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3001195

RESUMEN

Serum angiotensin-converting enzyme activity was measured in 91 adult healthy and lepromatous armadillos before inoculation with M. leprae and at necropsises. Mean ACE values were significantly elevated in armadillos with leprosy and the degree of elevation was roughly proportional to the extent of infection. There was also significant difference in the serum ACE levels between Florida and Louisiana armadillos. The dapsone treatment resulted in bringing these levels to normal. Serial assays of serum, ACE provided information on the response of armadillos to dapsone therapy.


Asunto(s)
Lepra/enzimología , Peptidil-Dipeptidasa A/sangre , Animales , Armadillos/sangre , Dapsona/uso terapéutico , Florida , Lepra/tratamiento farmacológico , Louisiana , Venezuela
13.
Hansen. int ; 9(1/2): 3-9, jun.-dez. 1984. tab
Artículo en Inglés | LILACS | ID: lil-71252

RESUMEN

The in vitro effect of Mycobacterium leprae suspensions on the PMN hability to phagocyting and killing Candida albicans and Candida pseudotropicalis was studied in forty-five patients of Hansen's disease and in fifteen healthy controls. Our results show no significative differences between the diferent studied groups, both for the phagocytosis and for the lysis of yeasts. There was no significant changes in the mean values of these functions after previous or simultaneously incubation with Mycobacterium leprae suspensions. Those observations confirmed that there are not alterations in the enzimatic battery of PMN in Hansen's disease patients and that the Mycobacterium leprae presence does not exert stimulating effect on this in vitro model


Asunto(s)
Humanos , Candida albicans , Lepra/enzimología , Técnicas In Vitro , Mycobacterium leprae/enzimología , Neutrófilos/enzimología
15.
s.l; s.n; Apr.-Jun. 1983. 11 p. ilus, tab.
No convencional en Inglés, Español | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1240772

RESUMEN

The purpose of this study was to investigate the presence of peroxidase (PO) in the histiocytes which are found in the lepromatous lesions of patients with nodular lepromatous leprosy (NLL). We studied dermoepidermal biopsy specimens from lepromstous lesions and blood smears of 10 patients with NLL, eight males and twoo females 28 to 63 years age (average 45 + or - 6.2), of which nine coursed with the stable form of the disease and one was in lepromatous reaction. Six had received treatment with diaminodiphenylsulphone for more than six months, and the other four, none. As controls we studied the blood smears of 10 healthy controls and 10 rat liver sections. PO was investigated in histiocytes, Kupffer cells and polymorphonuclears by dichlorhydrate oxydation, according to the technique of Kaplow. By means of Fite-Faraco´s stain, all ten cases proved to have abundant phagocytized M. leprae. PO was not found in histiocytes of lepromatous lesions in nine cases of stable NLL in lepromatous reaction. PO was present in Kupffer cells, in polymorphonuclears of patients with NLL and in controls. No difference was found either in the PO or M. leprae contents between treated and untreated patients. The PO deficiency in histiocytes of patients with NLL may be related to an incapacity of these cells to destroy M. leprae.


Asunto(s)
Masculino , Femenino , Humanos , Animales , Adulto , Persona de Mediana Edad , Anciano , Ratas , Fagocitosis , Lepra/enzimología , Lepra/patología , Histiocitos/enzimología , Piel/enzimología , Piel/patología , Peroxidasas/deficiencia
17.
Hansenol Int ; 5(2): 119-22, 1980 Dec.
Artículo en Español | MEDLINE | ID: mdl-7341484

RESUMEN

The LDH isoenzymes levels in fresh serum of seven patients affected by different forms of hanseniasis from Argentina, were measured by acrylamide electrophoresis. In all cases the LDH-4 fraction was found elevated; on the contrary, LDH-2 was reduced. The LDH-5 fraction was detected in only three serums, all of them significantly increased when compared with controls.


Asunto(s)
L-Lactato Deshidrogenasa/sangre , Lepra/enzimología , Electroforesis en Gel de Poliacrilamida , Humanos , Isoenzimas
18.
Hansenol Int ; 5(2): 93-111, 1980 Dec.
Artículo en Español | MEDLINE | ID: mdl-7341488

RESUMEN

The liver function was studied in 100 hanseniasis patients. They were classified in the following 10 groups: quiescent LL (20 patients), quiescent BL (13 patients), quiescent BB (7 patients), quiescent BT (9 patients), quiescent TT (12 patients), reactional LL (12 patients), reactional BL (10 patients), reactional BB (7 patients), reactional BT (5 patients), reactional TT (5 patients); a comparison was made with a control group (10 healthy individuals). It was found a hyperproteinemia with high levels of globulin and normal levels of albumin in the serum of all clinical forms, and a typical pattern of "light damage hepatic cells" with raised in the enzymatic activity of GOT, GPT and alkaline phosphatase with no changes in turbidity tests and bilirrubinemia, in all reactional patients. The physiopathology of this problem and the types III and IV hypersensitivity phenomena are discussed.


Asunto(s)
Lepra/fisiopatología , Pruebas de Función Hepática , Hígado/fisiopatología , Alanina Transaminasa/sangre , Fosfatasa Alcalina/sangre , Aspartato Aminotransferasas/sangre , Bilirrubina/sangre , Proteínas Sanguíneas/análisis , Femenino , Humanos , Lepra/enzimología , Masculino , Albúmina Sérica/análisis , Seroglobulinas/análisis
19.
s.l; s.n; sep. 1978. 11 p. ilus.
No convencional en Inglés | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1240770

RESUMEN

Lepromatous tissue from armadillos inoculated 24--36 months earlier with Mycobacterium leprae was obtained for electron microscopic studies. Cytochemically stained lepromas revealed a subpopulation of macrophages containing peroxisomes. These peroxidase reactive macrophages were not infected with bacilli. Acid phosphatase was present in macrophages and many of these were infected with bacilli and contained vacuoles and lipid globules. Within the membrane-bound vacuoles, acid phosphatase surrounded bacilli. However, the reaction product ended abruptly at a 15--40 millimicron thick zone of low electron density surrounding intact bacilli. Acid phosphatase was more intensely reactive and localized less precisely in heavily infected and vacuolated macrophages than in lightly and non-infected cells. The effectiveness of this bacillary barrier and the numerous infected macrophages with substantial acid phosphatase argue against the ability of acid phosphatase to protect host cells from leprosy bacilli. Evidence suggests a protective action of peroxidase or the rapid turnover of macrophages within lepromas. Granular and membranous debris were commonly seen within vacuoles of infected macrophages. A portion of the debris was ultrastructurally similar to bacillary matrix and was nonreactive for peroxidase and acid phosphatase. Following homogenization and centrifugation, similar materials banded with bacilli above 60% sucrose. Another portion of the debris was ultrastructurally similar to host lysosomal matrix and was reactive for acid phosphatase. Results support the concept of dual host and parasitic origins of the debris found in phagolysosomes of infected macrophages. Transparent, oval Epon defects remained eccentric to the majority of intact bacilli in centrifuged fractions. Apparently, an intrinsic property of leprosy produced these Epon defects.


Asunto(s)
Animales , Lepra/enzimología , Lepra/microbiología , Histocitoquímica , Macrófagos/enzimología , Macrófagos/microbiología , Modelos Animales de Enfermedad , Mycobacterium leprae/aislamiento & purificación , Peroxidasas/metabolismo
20.
s.l; s.n; sep. 1978. 7 p. ilus, tab.
No convencional en Inglés | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1240771

RESUMEN

Lysozyme activities of skin granulomas of 24 patients in leprosy were studied. Lepra cells of all 15 lepromatous leprosy showed strong lysozyme activity in cytoplasma. In the specimens stained with lysozyme and Ziehl-Neelsen's carbolfuchsin double stain conspicuous lysozyme activity around M. leprae were observed. One borderline case was negative. Lysozyme of epithelioid cells and giant cells of 10 tuberculoid types were completely negative. These results suggest that lysozyme plays only a small role in the disposal of M. leprae in macrophages and other mechanisms than bacteriolytic function of lysozyme are responsible for the defence against these bacilli.


Asunto(s)
Humanos , Lepra/enzimología , Macrófagos/enzimología , Macrófagos/microbiología , Muramidasa/metabolismo , Mycobacterium leprae/citología , Piel/enzimología
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