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1.
Mem Inst Oswaldo Cruz ; 118: e220044, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36995847

RESUMEN

BACKGROUND: Dendritic cells (DCs) specific intercellular adhesion molecule (ICAM)-3-grabbing non integrin receptor (DC-SIGN) binds to subgenera Leishmania promastigotes mediating its interaction with DC and neutrophils, potentially influencing the infection outcome. OBJECTIVES: In this work, we investigated whether DC-SIGN receptor is expressed in cells from cutaneous leishmaniasis (CL) lesions as well as the in vitro binding pattern of Leishmania (Viannia) braziliensis (Lb) and L. (L.) amazonensis (La) promastigotes. METHODS: DC-SIGN receptor was labeled by immunohistochemistry in cryopreserved CL tissue fragments. In vitro binding assay with CFSE-labeled Lb or La promastigotes and RAJI-transfecting cells expressing DC-SIGN (DC-SIGNPOS) or mock-transfected (DC-SIGNNEG) were monitored by flow cytometry at 2 h, 24 h and 48 h in co-culture. RESULTS: In CL lesion infiltrate, DC-SIGNPOS cells were present in the dermis and near the epidermis. Both Lb and La bind to DC-SIGNPOS cells, while binding to DC-SIGNNEG was low. La showed precocious and higher affinity to DC-SIGNhi population than to DC-SIGNlow, while Lb binding was similar in these populations. CONCLUSION: Our results demonstrate that DC-SIGN receptor is present in L. braziliensis CL lesions and interact with Lb promastigotes. Moreover, the differences in the binding pattern to Lb and La suggest DC-SIGN can influence in a difference way the intake of the parasites at the first hours after Leishmania infection. These results raise the hypothesis that DC-SIGN receptor could participate in the immunopathogenesis of American tegumentary leishmaniasis accounting for the differences in the outcome of the Leishmania spp. infection.


Asunto(s)
Leishmania braziliensis , Leishmania , Leishmaniasis Cutánea , Humanos , Leishmania braziliensis/metabolismo , Leishmaniasis Cutánea/parasitología , Moléculas de Adhesión Celular/metabolismo
2.
Mem. Inst. Oswaldo Cruz ; 118: e220044, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1430841

RESUMEN

BACKGROUND Dendritic cells (DCs) specific intercellular adhesion molecule (ICAM)-3-grabbing non integrin receptor (DC-SIGN) binds to subgenera Leishmania promastigotes mediating its interaction with DC and neutrophils, potentially influencing the infection outcome. OBJECTIVES In this work, we investigated whether DC-SIGN receptor is expressed in cells from cutaneous leishmaniasis (CL) lesions as well as the in vitro binding pattern of Leishmania (Viannia) braziliensis (Lb) and L. (L.) amazonensis (La) promastigotes. METHODS DC-SIGN receptor was labeled by immunohistochemistry in cryopreserved CL tissue fragments. In vitro binding assay with CFSE-labeled Lb or La promastigotes and RAJI-transfecting cells expressing DC-SIGN (DC-SIGNPOS) or mock-transfected (DC-SIGNNEG) were monitored by flow cytometry at 2 h, 24 h and 48 h in co-culture. RESULTS In CL lesion infiltrate, DC-SIGNPOS cells were present in the dermis and near the epidermis. Both Lb and La bind to DC-SIGNPOS cells, while binding to DC-SIGNNEG was low. La showed precocious and higher affinity to DC-SIGNhi population than to DC-SIGNlow, while Lb binding was similar in these populations. CONCLUSION Our results demonstrate that DC-SIGN receptor is present in L. braziliensis CL lesions and interact with Lb promastigotes. Moreover, the differences in the binding pattern to Lb and La suggest DC-SIGN can influence in a difference way the intake of the parasites at the first hours after Leishmania infection. These results raise the hypothesis that DC-SIGN receptor could participate in the immunopathogenesis of American tegumentary leishmaniasis accounting for the differences in the outcome of the Leishmania spp. infection.

3.
J Immunol Res ; 2021: 6657785, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33860062

RESUMEN

BACKGROUND: Cytokines and growth factors involved in the tissue inflammatory process influence the outcome of Leishmania infection. Insulin-like growth factor (IGF-I) constitutively present in the skin may participate in the inflammatory process and parasite-host interaction. Previous work has shown that preincubation of Leishmania (Leishmania) amazonensis with recombinant IGF-I induces accelerated lesion development. However, in human cutaneous leishmaniasis (CL) pathogenesis, it is more relevant to the persistent inflammatory process than progressive parasite proliferation. In this context, we aimed to investigate whether IGF-I was present in the CL lesions and if this factor may influence the lesions' development acting on parasite growth and/or on the inflammatory/healing process. Methodology. Fifty-one CL patients' skin lesion samples from endemic area of L. (Viannia) braziliensis infection were submitted to histopathological analysis and searched for Leishmania and IGF-I expression by immunohistochemistry. RESULTS: In human CL lesions, IGF-I was observed preferentially in the late lesion (more than 90 days), and the percentage of positive area for IGF-I was positively correlated with duration of illness (r = 0.42, P < 0.05). IGF-I was highly expressed in the inflammatory infiltrate of CL lesions from patients evolving with good response to therapy (2.8% ± 2.1%; median = 2.1%; n = 18) than poor responders (1.3% ± 1.1%; median: 1.05%; n = 6; P < 0.05). CONCLUSIONS: It is the first time that IGF-I was detected in lesions of infectious cutaneous disease, specifically in American tegumentary leishmaniasis. IGF-I was related to chronicity and good response to treatment. We may relate this finding to the efficient anti-inflammatory response and the known action of IGF-I in wound repair. The present data highlight the importance of searching nonspecific factors besides adaptive immune elements in the study of leishmaniasis' pathogenesis.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina/metabolismo , Leishmania braziliensis/inmunología , Leishmaniasis Cutánea/inmunología , Piel/patología , Adolescente , Adulto , Animales , Brasil , Femenino , Interacciones Huésped-Parásitos/inmunología , Humanos , Leishmania braziliensis/aislamiento & purificación , Leishmaniasis Cutánea/diagnóstico , Leishmaniasis Cutánea/parasitología , Leishmaniasis Cutánea/patología , Masculino , Persona de Mediana Edad , Piel/inmunología , Piel/microbiología , Cicatrización de Heridas/inmunología , Adulto Joven
4.
Acta Trop ; 218: 105890, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33744245

RESUMEN

Leishmania (Viannia) braziliensis is one of the main etiological agents of tegumentary leishmaniasis in Latin America. The establishment of a successful infection in host cells requires several key events including phagocytosis, phagolysosomal maturation impairment, and parasite replication. Autophagy is accountable for the physiological turnover of cellular organelles, degradation of macromolecular structures, and pathogen elimination. In many cases, autophagy control leads to a successful infection, both impairing pathogen elimination or providing nutrients. Here, we have investigated the relationship between autophagy and L. braziliensis infection. We observed that BECLIN1 expression was upregulated early on infection in both in vitro macrophage cultures and biopsies of cutaneous lesions from L. braziliensis infected patients. On the other hand, LC3B expression was downregulated in cutaneous lesions biopsies. A transient pattern of LC3+ cells was observed along L. braziliensis infection, but the number of LC3 puncta did not vary. Additionally, autophagy induction, with rapamycin treatment or through starvation, reduced infection. As expected, rapamycin increased the percentage of LC3+ cells and the number of puncta, but the presence of parasite restricted this effect, indicating LC3-associated autophagy impairment by L. braziliensis. Finally, silencing LC3B but not BECLIN1 promoted infection, confirming BECLIN1 independent and LC3B-related control by the parasite. Taken together, these data indicate macrophage autophagic machinery manipulation by L. braziliensis, resulting in successful establishment and survival into the host cell.


Asunto(s)
Autofagia , Leishmania braziliensis/fisiología , Leishmaniasis Cutánea/inmunología , Macrófagos/citología , Macrófagos/parasitología , Animales , Beclina-1/metabolismo , Femenino , Humanos , Leishmaniasis Cutánea/metabolismo , Macrófagos/inmunología , Proteínas Asociadas a Microtúbulos/metabolismo , Fagocitosis
5.
Rev Soc Bras Med Trop ; 52: e20180323, 2019 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-30994803

RESUMEN

We report the case of a 32-year-old man from Rio de Janeiro, who was infected in the Amazon region of Brazil by Leishmania (Viannia) naiffi. Generally, patients with L. naiffi cutaneous leishmaniasis exhibit a good therapeutic response to either pentavalent antimonials or pentamidine. However, after pentamidine treatment, this patient's infection evolved to therapeutic failure. To understand this clinical outcome, we investigated the presence of the Leishmania RNA virus (LRV) in parasites isolated from the cutaneous lesion; herein, we discuss the possible association between a poor response to pentamidine therapy and the presence of the LRV.


Asunto(s)
Leishmania/virología , Leishmaniasis Cutánea/tratamiento farmacológico , Pentamidina/uso terapéutico , Virus ARN/genética , Tripanocidas/uso terapéutico , Adulto , Humanos , Masculino , Pentamidina/efectos adversos , Reacción en Cadena de la Polimerasa , Insuficiencia del Tratamiento , Tripanocidas/efectos adversos
6.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;52: e20180323, 2019. graf
Artículo en Inglés | LILACS | ID: biblio-1003132

RESUMEN

Abstract We report the case of a 32-year-old man from Rio de Janeiro, who was infected in the Amazon region of Brazil by Leishmania (Viannia) naiffi. Generally, patients with L. naiffi cutaneous leishmaniasis exhibit a good therapeutic response to either pentavalent antimonials or pentamidine. However, after pentamidine treatment, this patient's infection evolved to therapeutic failure. To understand this clinical outcome, we investigated the presence of the Leishmania RNA virus (LRV) in parasites isolated from the cutaneous lesion; herein, we discuss the possible association between a poor response to pentamidine therapy and the presence of the LRV.


Asunto(s)
Humanos , Masculino , Adulto , Pentamidina/uso terapéutico , Virus ARN/genética , Tripanocidas/uso terapéutico , Leishmaniasis Cutánea/tratamiento farmacológico , Leishmania/virología , Pentamidina/efectos adversos , Tripanocidas/efectos adversos , Reacción en Cadena de la Polimerasa , Insuficiencia del Tratamiento
7.
Int J Infect Dis ; 57: 132-137, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28167253

RESUMEN

BACKGROUND: Leishmania (Viannia) braziliensis is the main etiological agent of tegumentary leishmaniasis in the Americas. Parasite molecular diversity and host immune status contribute to extensive variations in its clinical presentation within endemic areas of Brazil. Pentavalent antimonials have been used for more than 60 years as the first-line drug for all cases, despite the potential for severe side effects and refractoriness. In Rio de Janeiro, Brazil, most L. (V.) braziliensis infections are benign with a scarcity of parasites, although metastasis and refractory infections can arise. In this scenario, the use of novel molecular tools can be useful for diagnosis and to assess tissue parasitism, and is of benefit to clinical and therapeutic management. METHODS: In this study, parasite load was assessed by real-time PCR based on the leishmanial small subunit ribosomal RNA gene. RESULTS AND CONCLUSION: The data revealed a tendency to higher tissue parasitism in the skin compared to mucous lesion sites and a reduction with disease progression. Parasite load was lower in poor compared to good responders to antimonials, and was also reduced in recurrent lesions compared to primary ones. However, parasite load became higher with sequential relapses, pointing to an immune system inability to control the infection. Therefore the parasite burden does not seem to be a good predictor of disease progression.


Asunto(s)
Leishmania braziliensis/aislamiento & purificación , Leishmaniasis Cutánea/etiología , Carga de Parásitos , Animales , Células Cultivadas , Progresión de la Enfermedad , Humanos , Leishmaniasis Cutánea/parasitología , Reacción en Cadena en Tiempo Real de la Polimerasa
8.
Mem Inst Oswaldo Cruz ; 108(5): 665-7, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23903986

RESUMEN

Leishmania RNA virus (LRV) has been shown to be a symbiotic component of Leishmania parasites in South America. Nested retro-transcription polymerase chain reaction was employed to investigate LRV1 presence in leishmaniasis lesions from Brazil. In endemic areas of Rio de Janeiro (RJ), no LRV1 infection was observed even with mucosal involvement. LRV1 was only detected in Leishmania (V.) guyanensis cutaneous lesions from the northern region, which were obtained from patients presenting with disease reactivation after clinical cure of their primary lesions. Our results indicated that the severity of leishmaniasis in some areas of RJ, where Leishmania (V.) brazi-liensis is the primary etiological agent, was not associated with Leishmania LRV1 infection.


Asunto(s)
Leishmania braziliensis/virología , Leishmaniasis Cutánea/parasitología , Virus ARN/genética , Brasil , Femenino , Humanos , Reacción en Cadena de la Polimerasa , Virus ARN/clasificación , ARN Viral/genética , Índice de Severidad de la Enfermedad
9.
Mem. Inst. Oswaldo Cruz ; 108(5): 665-667, ago. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-680769

RESUMEN

Leishmania RNA virus (LRV) has been shown to be a symbiotic component of Leishmania parasites in South America. Nested retro-transcription polymerase chain reaction was employed to investigate LRV1 presence in leishmaniasis lesions from Brazil. In endemic areas of Rio de Janeiro (RJ), no LRV1 infection was observed even with mucosal involvement. LRV1 was only detected in Leishmania (V.) guyanensis cutaneous lesions from the northern region, which were obtained from patients presenting with disease reactivation after clinical cure of their primary lesions. Our results indicated that the severity of leishmaniasis in some areas of RJ, where Leishmania (V.) brazi-liensis is the primary etiological agent, was not associated with Leishmania LRV1 infection.


Asunto(s)
Femenino , Humanos , Leishmania braziliensis/virología , Leishmaniasis Cutánea/parasitología , Virus ARN/genética , Brasil , Reacción en Cadena de la Polimerasa , Virus ARN/clasificación , ARN Viral/genética , Índice de Severidad de la Enfermedad
10.
PLoS Negl Trop Dis ; 6(9): e1816, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23029578

RESUMEN

INTRODUCTION: Localized Cutaneous Leishmaniasis (LCL) and Mucosal Leishmaniasis (ML) are two extreme clinical forms of American Tegumentary Leishmaniasis that usually begin as solitary primary cutaneous lesions. Host and parasite factors that influence the progression of LCL to ML are not completely understood. In this manuscript, we compare the gene expression profiles of primary cutaneous lesions from patients who eventually developed ML to those that did not. METHODS: Using RNA-seq, we analyzed both the human and Leishmania transcriptomes in primary cutaneous lesions. RESULTS: Limited number of reads mapping to Leishmania transcripts were obtained. For human transcripts, compared to ML patients, lesions from LCL patients displayed a general multi-polarization of the adaptive immune response and showed up-regulation of genes involved in chemoattraction of innate immune cells and in antigen presentation. We also identified a potential transcriptional signature in the primary lesions that may predict long-term disease outcome. CONCLUSIONS: We were able to simultaneously sequence both human and Leishmania mRNA transcripts in primary cutaneous leishmaniasis lesions. Our results suggest an intrinsic difference in the immune capacity of LCL and ML patients. The findings correlate the complete cure of L. braziliensis infection with a controlled inflammatory response and a balanced activation of innate and adaptive immunity.


Asunto(s)
Interacciones Huésped-Patógeno , Leishmania braziliensis/patogenicidad , Leishmaniasis Cutánea/patología , Leishmaniasis Cutánea/parasitología , Transcriptoma , Adolescente , Adulto , Anciano , Femenino , Humanos , Leishmania braziliensis/genética , Masculino , Persona de Mediana Edad , Adulto Joven
11.
Mem Inst Oswaldo Cruz ; 107(5): 664-74, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22850958

RESUMEN

In this study, PCR assays targeting different Leishmania heat-shock protein 70 gene (hsp70) regions, producing fragments ranging in size from 230-390 bp were developed and evaluated to determine their potential as a tool for the specific molecular diagnosis of cutaneous leishmaniasis (CL). A total of 70 Leishmania strains were analysed, including seven reference strains (RS) and 63 previously typed strains. Analysis of the RS indicated a specific region of 234 bp in the hsp70 gene as a valid target that was highly sensitive for detection of Leishmania species DNA with capacity of distinguishing all analyzed species, after polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). This PCR assay was compared with other PCR targets used for the molecular diagnosis of leishmaniasis: hsp70 (1400-bp region), internal transcribed spacer (ITS)1 and glucose-6-phosphate dehydrogenase (G6pd). A good agreement among the methods was observed concerning the Leishmania species identification. Moreover, to evaluate the potential for molecular diagnosis, we compared the PCR targets hsp70-234 bp, ITS1, G6pd and mkDNA using a panel of 99 DNA samples from tissue fragments collected from patients with confirmed CL. Both PCR-hsp70-234 bp and PCR-ITS1 detected Leishmania DNA in more than 70% of the samples. However, using hsp70-234 bp PCR-RFLP, identification of all of the Leishmania species associated with CL in Brazil can be achieved employing a simpler and cheaper electrophoresis protocol.


Asunto(s)
ADN Protozoario/genética , Proteínas HSP70 de Choque Térmico/genética , Leishmania/genética , Leishmaniasis Cutánea/diagnóstico , Reacción en Cadena de la Polimerasa/métodos , Humanos , Leishmania/aislamiento & purificación , Leishmaniasis Cutánea/parasitología , Polimorfismo de Longitud del Fragmento de Restricción , Sensibilidad y Especificidad
12.
Mem. Inst. Oswaldo Cruz ; 107(5): 664-674, Aug. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-643753

RESUMEN

In this study, PCR assays targeting different Leishmania heat-shock protein 70 gene (hsp70) regions, producing fragments ranging in size from 230-390 bp were developed and evaluated to determine their potential as a tool for the specific molecular diagnosis of cutaneous leishmaniasis (CL). A total of 70 Leishmania strains were analysed, including seven reference strains (RS) and 63 previously typed strains. Analysis of the RS indicated a specific region of 234 bp in the hsp70 gene as a valid target that was highly sensitive for detection of Leishmania species DNA with capacity of distinguishing all analyzed species, after polymerase chain reaction-restriction fragment length polymorfism (PCR-RFLP). This PCR assay was compared with other PCR targets used for the molecular diagnosis of leishmaniasis: hsp70 (1400-bp region), internal transcribed spacer (ITS)1 and glucose-6-phosphate dehydrogenase (G6pd). A good agreement among the methods was observed concerning the Leishmania species identification. Moreover, to evaluate the potential for molecular diagnosis, we compared the PCR targets hsp70-234 bp, ITS1, G6pd and mkDNA using a panel of 99 DNA samples from tissue fragments collected from patients with confirmed CL. Both PCR-hsp70-234 bp and PCR-ITS1 detected Leishmania DNA in more than 70% of the samples. However, using hsp70-234 bp PCR-RFLP, identification of all of the Leishmania species associated with CL in Brazil can be achieved employing a simpler and cheaper electrophoresis protocol.


Asunto(s)
Humanos , ADN Protozoario/genética , /genética , Leishmania/genética , Leishmaniasis Cutánea/diagnóstico , Reacción en Cadena de la Polimerasa/métodos , Leishmania/aislamiento & purificación , Leishmaniasis Cutánea/parasitología , Polimorfismo de Longitud del Fragmento de Restricción , Sensibilidad y Especificidad
13.
Acta Trop ; 119(2-3): 160-4, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21663729

RESUMEN

Infection of humans with Leishmania braziliensis typically results in localized cutaneous leishmaniasis (LCL). Rarely, after months or years of apparent clinical cure, some patients develop the destructive mucosal leishmaniasis (ML). ML results from L. braziliensis dissemination, probably via phagocytic cells. As the preferred cells for Leishmania spp. colonization, macrophages are critical to infection control, and may contribute to parasite dissemination. However, the host factors that determine this outcome are unknown. Matrix metalloproteinase 9 (MMP-9) is known to be important for immune cell migration, macrophage recruitment, and effective granuloma formation. Moreover, MMP-9 has been involved in Mycobacterium tuberculosis dissemination. Here, we demonstrate that in vitro infection of human macrophages with L. braziliensis increased the secretion and activation of MMP-9. We also demonstrate that macrophages from healthy cured individuals with previous history of ML had increased MMP-9 activity compared to LCL cured individuals. These findings may represent a fundamental difference in host innate immunity that could contribute to the clinical leishmaniasis presentation.


Asunto(s)
Leishmania braziliensis/inmunología , Leishmania braziliensis/patogenicidad , Leishmaniasis Mucocutánea/patología , Macrófagos/parasitología , Metaloproteinasa 9 de la Matriz/metabolismo , Adolescente , Adulto , Anciano , Animales , Humanos , Leishmaniasis Mucocutánea/inmunología , Leishmaniasis Mucocutánea/parasitología , Macrófagos/enzimología , Persona de Mediana Edad , Adulto Joven
14.
Mem Inst Oswaldo Cruz ; 102(5): 625-30, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17710308

RESUMEN

Subclinical or asymptomatic infection is documented in individuals living in endemic areas for leishmaniasis suggesting that the development of an appropriate immune response can control parasite replication and maintain tissue integrity. A low morbidity indicates that intrinsic factors could favor resistance to Leishmania infection. Herein, leishmanial T-cell responses induced in subjects with low susceptibility to leishmaniasis as asymptomatic subjects were compared to those observed in cured cutaneous leishmaniasis (CCL) patients, who controlled the disease after antimonial therapy. All of them have shown maintenance of specific long-term immune responses characterized by expansion of higher proportions of CD4+ as compared to CD8+ Leishmania reactive T-lymphocytes. Asymptomatic subjects had lower indexes of in vitro Leishmania induced lymphoproliferative responses and interferon-gamma (IFN-gamma) production in comparison to CCL patients. On the other hand, interleukin (IL-10) production was much higher in asymptomatics than in CCL, while no differences in IL-5 levels were found. In conclusion, long lived T-cell responses achieved by asymptomatic individuals differed from those who had developed symptomatic leishmaniasis in terms of intensity of lymphocyte activation (proliferation or IFN-gamma) and regulatory mechanisms (IL-10). The absence of the disease in asymptomatics could be explained by their intrinsic ability to create a balance between immunoregulatory (IL-10) and effector cytokines (IFN-gamma), leading to parasite destruction without producing skin tissue damage. The establishment of profiles of cell-mediated immune responses associated with resistance against Leishmania infection is likely to make new inroads into understanding the long-lived immune protection against the disease.


Asunto(s)
Antígenos de Protozoos/inmunología , Leishmania braziliensis/inmunología , Leishmaniasis Cutánea/inmunología , Activación de Linfocitos/inmunología , Linfocitos T/inmunología , Animales , Antimonio/uso terapéutico , Antiprotozoarios/uso terapéutico , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Células Cultivadas , Citocinas/inmunología , Enfermedades Endémicas , Femenino , Humanos , Leishmaniasis Cutánea/tratamiento farmacológico , Masculino , Compuestos Organometálicos/uso terapéutico
15.
Mem. Inst. Oswaldo Cruz ; 102(5): 625-630, Aug. 2007. graf
Artículo en Inglés | LILACS | ID: lil-458636

RESUMEN

Subclinical or asymptomatic infection is documented in individuals living in endemic areas for leishmaniasis suggesting that the development of an appropriate immune response can control parasite replication and maintain tissue integrity. A low morbidity indicates that intrinsic factors could favor resistance to Leishmania infection. Herein, leishmanial T-cell responses induced in subjects with low susceptibility to leishmaniasis as asymptomatic subjects were compared to those observed in cured cutaneous leishmaniasis (CCL) patients, who controlled the disease after antimonial therapy. All of them have shown maintenance of specific long-term immune responses characterized by expansion of higher proportions of CD4+ as compared to CD8+ Leishmania reactive T-lymphocytes. Asymptomatic subjects had lower indexes of in vitro Leishmania induced lymphoproliferative responses and interferon-gamma (IFN-gamma) production in comparison to CCL patients. On the other hand, interleukin (IL-10) production was much higher in asymptomatics than in CCL, while no differences in IL-5 levels were found. In conclusion, long lived T-cell responses achieved by asymptomatic individuals differed from those who had developed symptomatic leishmaniasis in terms of intensity of lymphocyte activation (proliferation or IFN-gamma) and regulatory mechanisms (IL-10). The absence of the disease in asymptomatics could be explained by their intrinsic ability to create a balance between immunoregulatory (IL-10) and effector cytokines (IFN-gamma), leading to parasite destruction without producing skin tissue damage. The establishment of profiles of cell-mediated immune responses associated with resistance against Leishmania infection is likely to make new inroads into understanding the long-lived immune protection against the disease.


Asunto(s)
Animales , Femenino , Humanos , Masculino , Antígenos de Protozoos/inmunología , Leishmania braziliensis/inmunología , Leishmaniasis Cutánea/inmunología , Activación de Linfocitos/inmunología , Linfocitos T/inmunología , Antimonio/uso terapéutico , Antiprotozoarios/uso terapéutico , /inmunología , /inmunología , Células Cultivadas , Citocinas/inmunología , Enfermedades Endémicas , Leishmaniasis Cutánea/tratamiento farmacológico , Compuestos Organometálicos/uso terapéutico
16.
Rev Soc Bras Med Trop ; 39(4): 323-6, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17119744

RESUMEN

Despite more than half a century of use in leishmaniasis, antimony therapy still presents serious problems concerning dosage and toxicity. Low and high doses have been shown to be equally effective. In this paper, the feasibility of injecting one ampoule of meglumine antimoniate intramuscularly every other day until clinical cure is demonstrated, while studying a series of 40 cutaneous leishmaniasis cases. Total dose used varied from 1,822.5 to 12,150 mg of pentavalent antimony and total time of treatment varied from 3 to 10 weeks, with 86% efficacy. Thirty-six out of the 40 patients are still on follow-up with a mean time of 10.7 +/- 7 months and a median of 9 months. No relapse or mucosal lesions have been noted so far. The schedule showed good tolerance and easy application and its efficacy was comparable to the officially recommended WHO schedule. Therefore, such a schedule represents a valuable alternative for the cases with high toxicicity to antimony or daily injections are an obstacle to the treatment.


Asunto(s)
Antiprotozoarios/administración & dosificación , Leishmaniasis Cutánea/tratamiento farmacológico , Meglumina/administración & dosificación , Compuestos Organometálicos/administración & dosificación , Adolescente , Adulto , Anciano , Antiprotozoarios/efectos adversos , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intramusculares , Masculino , Meglumina/efectos adversos , Antimoniato de Meglumina , Persona de Mediana Edad , Compuestos Organometálicos/efectos adversos , Factores de Tiempo , Resultado del Tratamiento
17.
Rev Soc Bras Med Trop ; 39(4): 376-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17119754

RESUMEN

Two mucocutaneous leishmaniasis cases resistant to therapy are reported here. After the failure of initial therapies (antimony, amphotericin B and/or pentamidine) patients received a low-dose schedule: one ampoule of meglumine antimoniate (405 mg of pentavalent antimony [Sb v]) by intramuscular injection, three times a week until complete healing of the lesions. One patient was cured with a total of 30 ampoules in 10 weeks and the other received 36 ampoules in 12 weeks. Both remain clinically cured after one year of follow-up.


Asunto(s)
Antiprotozoarios/administración & dosificación , Leishmaniasis Cutánea/tratamiento farmacológico , Meglumina/administración & dosificación , Compuestos Organometálicos/administración & dosificación , Adulto , Esquema de Medicación , Enfermedades del Oído/tratamiento farmacológico , Oído Externo , Estudios de Seguimiento , Humanos , Inyecciones Intramusculares , Masculino , Antimoniato de Meglumina , Persona de Mediana Edad , Enfermedades del Pene/tratamiento farmacológico , Resultado del Tratamiento
18.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;39(4): 323-326, jul.-ago. 2006. ilus, tab
Artículo en Inglés | LILACS | ID: lil-439872

RESUMEN

Despite more than half a century of use in leishmaniasis, antimony therapy still presents serious problems concerning dosage and toxicity. Low and high doses have been shown to be equally effective. In this paper, the feasibility of injecting one ampoule of meglumine antimoniate intramuscularly every other day until clinical cure is demonstrated, while studying a series of 40 cutaneous leishmaniasis cases. Total dose used varied from 1,822.5 to 12,150mg of pentavalent antimony and total time of treatment varied from 3 to 10 weeks, with 86 percent efficacy. Thirty-six out of the 40 patients are still on follow-up with a mean time of 10.7 ± 7 months and a median of 9 months. No relapse or mucosal lesions have been noted so far. The schedule showed good tolerance and easy application and its efficacy was comparable to the officially recommended WHO schedule. Therefore, such a schedule represents a valuable alternative for the cases with high toxicicity to antimony or daily injections are an obstacle to the treatment.


Apesar de utilizado há mais de meio século no tratamento da leishmaniose, o antimônio apresenta ainda problemas quanto a sua toxicidade e dose ideal. Doses baixas têm se mostrado tão eficazes quanto doses altas. Neste trabalho, apresentamos o resultado do emprego de uma ampola de antimoniato de meglumina intramuscular, em dias alternados, até a cura clínica, numa série de 40 casos. A dose total utilizada, por paciente, variou de 1.822,5 a 12.150mg de antimônio pentavalente e o tempo de tratamento de 3 a 10 semanas com eficácia de 86 por cento. Dos 40 pacientes estudados, 36 ainda estão em acompanhamento, com um tempo médio de 10,7 ± 7 meses e média de 9 meses. Não houve recidivas nem lesões mucosas. O esquema utilizado foi bem tolerado, de fácil aplicação, eficácia comparável ao esquema oficialmente preconizado pela OMS, mostrando-se como valiosa alternativa para os casos com potencial toxicidade ao antimônio ou cuja aplicação de injeções diárias represente um obstáculo ao tratamento.


Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Niño , Adolescente , Adulto , Persona de Mediana Edad , Antiprotozoarios/administración & dosificación , Leishmaniasis Cutánea/tratamiento farmacológico , Meglumina , Meglumina/administración & dosificación , Compuestos Organometálicos/administración & dosificación , Antiprotozoarios/efectos adversos , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Estudios de Seguimiento , Inyecciones Intramusculares , Meglumina/efectos adversos , Compuestos Organometálicos/efectos adversos , Factores de Tiempo , Resultado del Tratamiento
19.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;39(4): 376-378, jul.-ago. 2006. ilus
Artículo en Inglés | LILACS | ID: lil-439882

RESUMEN

Two mucocutaneous leishmaniasis cases resistant to therapy are reported here. After the failure of initial therapies (antimony, amphotericin B and/or pentamidine) patients received a low-dose schedule: one ampoule of meglumine antimoniate (405mg of pentavalent antimony [Sb v]) by intramuscular injection, three times a week until complete healing of the lesions. One patient was cured with a total of 30 ampoules in 10 weeks and the other received 36 ampoules in 12 weeks. Both remain clinically cured after one year of follow-up.


São relatados dois casos de leishmaniose mucocutânea resistentes ao tratamento. Depois das terapêuticas iniciais (antimônio, anfotericina B e/ou pentamidina), os pacientes receberam um esquema alternativo: uma ampola de antimoniato de meglumina (405mg de antimônio pentavalnte [Sb v]) por via intramuscular, três vezes por semana até a cura completa das lesões. Um paciente recebeu um total de 30 ampolas durante 10 semanas e o outro, 36 ampolas durante 12 semanas. Ambos permanecem clinicamente curados até um ano após o tratamento.


Asunto(s)
Humanos , Masculino , Adulto , Persona de Mediana Edad , Antiprotozoarios/administración & dosificación , Leishmaniasis Cutánea/tratamiento farmacológico , Meglumina/administración & dosificación , Compuestos Organometálicos/administración & dosificación , Esquema de Medicación , Estudios de Seguimiento , Inyecciones Intramusculares , Resultado del Tratamiento
20.
Trans R Soc Trop Med Hyg ; 100(12): 1112-7, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16765391

RESUMEN

One of the potential dangers of American tegumentary leishmaniasis (ATL) caused by Leishmania (Viannia) braziliensis is the development of mucosal lesions. Haematogenous dissemination of the parasite is the most likely mechanism to explain this occurrence, but most attempts to isolate the parasite from blood have so far been unsuccessful. The presence of Leishmania in peripheral blood was therefore evaluated by PCR using DNA samples isolated from patients presenting active cutaneous or mucosal disease, and from individuals cured by antimonial treatment as well as individuals without a past history of leishmaniasis but with a positive Montenegro skin test, all living in L. (V.) braziliensis-endemic areas. Leishmania DNA was found not only in those patients presenting active cutaneous (24.8%) or mucosal (35%) lesions, but also in samples isolated from healed individuals (27.3%) as well as in asymptomatic skin-test-positive residents of endemic areas (37.5%). Overall, PCR showed the presence of parasite DNA in the blood of 26.2% of the 225 examined samples. These data suggest that persistence of parasites within the host may last for many years and, rather than being a risk factor, might be important in maintaining the protective response in those living in endemic areas.


Asunto(s)
ADN Protozoario/sangre , Leishmania braziliensis/aislamiento & purificación , Leishmaniasis Mucocutánea/parasitología , Animales , Interacciones Huésped-Parásitos , Humanos , Leishmaniasis Mucocutánea/sangre , Leucocitos Mononucleares/parasitología , Sistema Linfático/parasitología , Reacción en Cadena de la Polimerasa/normas , Sensibilidad y Especificidad
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