RESUMEN
Although Mycobacterium leprae (M.leprae) is usually found in macrophages and nerves of the dermis of patients with multibacillary leprosy, it is also present in all layers of the epidermis, basal, suprabasal, prickle cells, and keratin layers. However, the mechanism by which M.leprae invades the dermis remains unknown, whereas the underlying mechanism by which M.leprae invades peripheral nerves, especially Schwann cells, is well defined. M. leprae binds to the α-dystroglycan (DG) of Schwann cells via the interaction of α-DG and laminin (LN) -α2 in the basal lamina, thus permitting it to become attached to and invade peripheral nerves. In the current study, we investigated the issue of how M.leprae is phagocytosed by human epidermal keratinocytes, neonatal (HEKn). LN-5 is the predominant form of laminin in the epidermis and allows the epidermis to be stably attached to the dermis via its interaction with α/ß-DG as well as integrins that are produced by keratinocytes. We therefore focused on the role of LN-5 when M. leprae is internalized by HEKn cells. Our results show that M.leprae preferentially binds to LN-5-coated slides and this binding to LN-5 enhances its binding to HEKn cells. The findings also show that pre-treatment with an antibody against α-DG, integrin-ß1, or -ß4 inhibited the binding of LN-5-coated M.leprae to HEKn cells. These results suggest that M. leprae binds to keratinocytes by taking advantage of the interaction of LN-5 in the basal lamina of the epidermis and a surface receptor of keratinocytes, such as α-DG, integrin-ß1, or -ß4.
Asunto(s)
Adhesión Bacteriana , Moléculas de Adhesión Celular/metabolismo , Distroglicanos/metabolismo , Integrina beta1/metabolismo , Integrina beta4/metabolismo , Queratinocitos/microbiología , Mycobacterium leprae/fisiología , Células Cultivadas , Humanos , Fagocitosis , Unión Proteica , KalininaRESUMEN
A/J mice were found to have amino acid differences in Naip5, one of the NOD-like receptors (NLRs) involved in the cytosolic recognition of pathogen-associated molecular patterns and one of the adaptor proteins for caspase-1 activation. This defect was associated with a susceptibility to Legionella infection, suggesting an important role for Naip5 in the immune response also to other intracellular pathogens, such as Mycobacterium leprae. In this study, the immune responses of macrophages from A/J mice against M. leprae were compared to those of macrophages from C57BL/6 mice. Infection with M. leprae induced high levels of TNF-alpha production and NF-kappaB activation in A/J and C57BL/6 macrophages. Caspase-1 activation and IL-1beta secretion were also induced in both macrophages. However, macrophages from A/J mice exhibited reduced caspase-1 activation and IL-1beta secretion compared to C57BL/6 macrophages. These results suggest that NLR family proteins may have a role in the innate immune response to M. leprae.
Asunto(s)
Caspasa 1/metabolismo , Sistema Inmunológico/fisiología , Interleucina-1beta/metabolismo , Lepra/inmunología , Macrófagos/inmunología , Mycobacterium leprae/inmunología , Animales , Ratones , Ratones Endogámicos A , Ratones Endogámicos C57BL , Mycobacterium leprae/patogenicidad , Proteína Inhibidora de la Apoptosis Neuronal/genética , Proteína Inhibidora de la Apoptosis Neuronal/inmunología , Especificidad de la EspecieRESUMEN
OBJECTIVE: Identification of the presence and drug resistance of Mycobacterium leprae is key to the diagnosis and treatment of leprosy in non-endemic country like Korea. The aim of this study was to screen the drug target DNA such as folP, rpoB, gyr, and 23S rRNA of drug resistance strain of M. leprae. PATIENTS AND METHODS: Sequences of those genes were analyzed for the 104 bacterial index positive cases out of 171 leprosy patients in Korea using touchdown PCR, single stranded conformational polymorphism. RESULTS: Twenty (19.2%) cases have shown the mutations in folP gene of dapsone-resistant M. leprae in which three (2.89%) cases were mutations in two genes, folP and rpoB, of multidrugs resistant strains to dapsone and rifampin, and two (1.92%) cases in folP and gyr genes of resistance to dapsone and oflaxacin, respectively. Besides double mutation for folP gene was one case (0.96%) and for rpoB gene one case, respectively. There was no mutant isolates in 23S rRNA gene against clarithromycin. CONCLUSIONS: This result should leads to a better understanding of the status of multidrug resistant leprosy in Korea and may assist in the rapid diagnosis of drug resistant M. leprae and the choice of the appropriate treatment regimens.
Asunto(s)
Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana/genética , Leprostáticos/farmacología , Lepra/microbiología , Mutación , Mycobacterium leprae/efectos de los fármacos , Adulto , Animales , Femenino , Humanos , Corea (Geográfico) , Leprostáticos/uso terapéutico , Lepra/tratamiento farmacológico , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Mycobacterium leprae/genética , Mycobacterium leprae/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Análisis de Secuencia de ADNRESUMEN
RIPK 2 is adapter molecule in the signal pathway involved in Toll-like receptors. However, there has been no reported association between receptor-interacting serine/threonine kinase 2 (RIPK 2) expression and the infectious diseases involving mycobacterial infection. This study found that its expression was down-regulated in the footpads and skin but was up-regulated in the liver of Mycobacterium leprae-infected nu/nu mice compared with those of the M. leprae non-infected nu/nu mice. It was observed that the interlukin-12p40 and interferon-gamma genes involved in the susceptibility of M. leprae were down-regulated in the skin but were up-regulated in the liver. Overall, this suggests that regulation of RIPK 2 expression is tissue-specifically associated with M. leprae infection.
Asunto(s)
Regulación hacia Abajo , Infecciones por Mycobacterium/metabolismo , Mycobacterium leprae , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Femenino , Pie , Interferón gamma/genética , Interferón gamma/metabolismo , Interleucina-12/genética , Interleucina-12/metabolismo , Subunidad p40 de la Interleucina-12 , Hígado/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Proteínas Serina-Treonina Quinasas/genética , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , ARN Mensajero/metabolismo , Proteína Serina-Treonina Quinasa 2 de Interacción con Receptor , Proteína Serina-Treonina Quinasas de Interacción con Receptores , Piel/metabolismo , Regulación hacia ArribaRESUMEN
The lack of methods to identify Mycobacterium leprae with the resistance against multi-drugs quickly and specifically has hindered effective chemotherapy against M. leprae infection. To screen M. leprae with resistance against multi-drugs, the Touch-Down (TD)-PCR has been used in this study. Sequences of the folP, rpoA, B, and gyrA, B genes were analyzed for isolates of M. leprae from leprosy patients in Korea. We amplified designated region of several genes in M. leprae involved in drug resistance and could obtain the PCR products of each gene. The mutations in the particular region of folP, rpoB, and gyrB gene were certified by TD-PCR single-stranded conformational polymorphism and DNA sequencing, respectively.
Asunto(s)
Farmacorresistencia Bacteriana Múltiple/genética , Leprostáticos/farmacología , Lepra/microbiología , Mycobacterium leprae/genética , Mutación Puntual , Reacción en Cadena de la Polimerasa/métodos , ADN Bacteriano/química , ADN Bacteriano/genética , Humanos , Corea (Geográfico) , Lepra/tratamiento farmacológico , Polimorfismo Genético , Polimorfismo Conformacional Retorcido-Simple , Análisis de Secuencia de ADNRESUMEN
Interleukin-12 receptor beta 1 ( IL12RB1), interleukin-12 receptor beta 2 ( IL12RB2), and interferon gamma receptor 1 ( IFNGR1) perform important roles in the host defense against intracellular pathogens such as Mycobacteria. Several mutations within their genes have been confirmed as associated with increased susceptibility to mycobacterial infection. However, the association between mutations of the IL12RB1, IL12RB2, and IFNGR1 encoding genes and lepromatous leprosy has not been studied. This study screened for polymorphisms within IL12RB1, IL12RB2, and IFNGR1 encoding genes in the Korean populations using polymerase chain reaction (PCR)/single-strand conformation polymorphism (SSCP) DNA sequencing assay, and an association study was performed using the missense mutations of 705 A/G (Q214R), 1196 G/C (G378R), 1637 G/A (A525T), and 1664 C/T (P534S) of the IL12RB1, 83 G/A (V14M), and 1443 T/C (L467P) for the IFNGR1 encoding genes. There were no differences in the genotype and allele frequencies of IL12RB1 and IFNGR1 genes between 93 lepromatous leprosy patients and 94 control subjects. In conclusion, missense mutations of 705 A/G (Q214R), 1196 G/C (G378R), 1637 G/A (A525T), 1664 C/T (P534S) of the IL12RB1, 83 G/A (V14 M), and 1443 T/C (L467P) of the IFNGR1 encoding genes have no association with the susceptibility to lepromatous leprosy in the Korean population.
Asunto(s)
Lepra Lepromatosa/genética , Mutación Missense , Receptores de Interferón/genética , Receptores de Interleucina/genética , Adulto , Anciano , Femenino , Predisposición Genética a la Enfermedad , Humanos , Corea (Geográfico) , Lepra Lepromatosa/etiología , Masculino , Persona de Mediana Edad , Receptores de Interleucina-12RESUMEN
The lack of methods to identify Mycobacterium leprae with the resistance against multi-drugs quickly and specifically has hindered effective chemotherapy against M. leprae infection. To screen M. leprae with resistance against multi-drugs, the Touch-Down (TD)-PCR has been used in this study. Sequences of the folP, rpoA, B, and gyrA, B genes were analyzed for isolates of M. leprae from leprosy patients in Korea. We amplified designated region of several genes in M. leprae involved in drug resistance and could obtain the PCR products of each gene. The mutations in the particular region of folP, rpoB, and gyrB gene were certified by TD-PCR single-stranded conformational polymorphism and DNA sequencing, respectively.