RESUMO
BACKGROUND: There is little information about the frequency of Leishmania infection in asymptomatic people living with HIV (PLWH) and about the performance of laboratory diagnostic methods in coinfected patients in Latin America. The main objective of this study is to evaluate the frequency of Leishmania spp. infection in HIV-infected patients living in an urban area in Brazil. METHODS: To detect Leishmania infection, diagnostic tests were performed to detect anti-Leishmania antibodies (ELISA using Leptomonas seymouri antigens; ELISA using rK39 antigens; ELISA using rK28 antigens; indirect fluorescent-antibody test (IFAT); direct agglutination test (DAT)) and Leishmania DNA (polymerase chain reaction (PCR) with the target genes kDNA and ITS-1). RESULTS: The frequency of at least one positive test was 15%. For ELISA using Leptomonas antigens and IFAT, there was an association between CD4+ T lymphocyte counts and test positivity, with a higher positivity of these tests in more immunosuppressed patients (CD4+ T cell count < 200/mm3). CONCLUSIONS: According to our data, there was a high prevalence of Leishmania spp. infections in this population living with HIV. Although there is the possibility of cross-reaction, some tests that are considered highly specific for the diagnosis of Leishmania infection were positive. There was also an association between the positivity of some tests studied and lower values of CD4+ T lymphocytes.
Assuntos
Coinfecção/epidemiologia , Infecções por HIV/epidemiologia , HIV , Leishmania/genética , Leishmania/imunologia , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes de Aglutinação , Animais , Brasil/epidemiologia , Contagem de Linfócito CD4 , Estudos de Coortes , Coinfecção/virologia , Estudos Transversais , DNA de Cinetoplasto/genética , Testes Diagnósticos de Rotina/métodos , Ensaio de Imunoadsorção Enzimática , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Infecções por HIV/virologia , Humanos , Leishmaniose Visceral/parasitologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Adulto JovemRESUMO
TNF-α, IFN-γ, IL-10, IL-17, CD68 and CD57 were evaluated in biopsies of patients with American cutaneous leishmaniasis living in Sorocaba, Brazil. The analyses were performed considering the time of lesions from 23 patients with recent lesions (Group I) and 19 patients with late lesions (Group II). All patients were infected with Leishmania (Viannia) braziliensis. Immunostaining cells for CD68, CD57, TNF- α, IFN-γ, IL-10 and IL-17 were performed by immunohistochemistry. Except for CD68 and IL-17, the distribution of in situ for CD57, IL-10, TNF-α and IFN-γ showed that patients with recent lesions expressed higher levels than those with late lesions. The comparison of cytokine expression/group showed that IL-10 was significantly higher than IL-17 and IFN-γ (similar data were shown in IL-17 compared with TNF-α), suggesting an immunological balance between inflammatory-anti-inflammatory agents. This balance was similar for two groups of patients. In conclusion, these data suggested that (i) patients from Group I had recent lesions (in the beginning of chronic phase) compared to those from Group II and (ii) the modulation of inflammatory response in patients with recent American cutaneous leishmaniasis was correlated with IL-10 expression in skin lesions preventing the development of mucosal forms. The parasite treatment also prevented the evolution of severe forms.
Assuntos
Citocinas/imunologia , Leishmania braziliensis/fisiologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/patologia , Adulto , Antígenos CD/análise , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/análise , Antígenos de Diferenciação Mielomonocítica/imunologia , Brasil , Antígenos CD57/análise , Antígenos CD57/imunologia , Citocinas/análise , Feminino , Humanos , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-IdadeRESUMO
Immunosuppression has been reported to occur during active visceral leishmaniasis and some factors such as the cytokine profile may be involved in this process. In the mouse model of cutaneous leishmaniasis using Leishmania (Leishmania) major, the Th1 response is related to protection while the Th2 response is related to disease progression. However, in hamsters, which are considered to be an excellent model for the study of visceral leishmaniasis, this dichotomy is not observed. Using outbred 45- to 60-day-old (140 to 150 g) male hamsters infected intraperitoneally with 2 x 10(7) L. (L.) chagasi amastigotes, we evaluated the immune response of spleen cells and the production of cytokines. We used 3 to 7 hamsters per group evaluated. We detected a preserved response to concanavalin A measured by index of proliferation during all periods of infection studied, while a proliferative response to Leishmania antigen was detected only at 48 and 72 h post-infection. Messenger RNA from cytokines type 1 (IL-2, TNF-α, IFN-γ) and type 2 (IL-4, IL-10 and TGF-β) detected by reverse transcriptase polymerase chain reaction and produced by spleen cells showed no qualitative difference between control non-infected hamsters and infected hamsters during any period of infection evaluated. Cytokines were measured by the DNA band intensity on agarose gel using the Image Lab 1D L340 software with no differences observed. In conclusion, the present results showed an antigen-dependent immunosuppression in hamsters with active visceral leishmaniasis that was not related to the cytokine profile.
Assuntos
Animais , Cricetinae , Masculino , Camundongos , Antígenos de Protozoários/imunologia , Citocinas/imunologia , Tolerância Imunológica/imunologia , Leishmania/imunologia , Leishmaniose Visceral/imunologia , Linfócitos T/imunologia , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Fator de Crescimento Transformador beta , Fatores de Crescimento Transformadores/imunologiaRESUMO
Immunosuppression has been reported to occur during active visceral leishmaniasis and some factors such as the cytokine profile may be involved in this process. In the mouse model of cutaneous leishmaniasis using Leishmania (Leishmania) major, the Th1 response is related to protection while the Th2 response is related to disease progression. However, in hamsters, which are considered to be an excellent model for the study of visceral leishmaniasis, this dichotomy is not observed. Using outbred 45- to 60-day-old (140 to 150 g) male hamsters infected intraperitoneally with 2 x 10(7) L. (L.) chagasi amastigotes, we evaluated the immune response of spleen cells and the production of cytokines. We used 3 to 7 hamsters per group evaluated. We detected a preserved response to concanavalin A measured by index of proliferation during all periods of infection studied, while a proliferative response to Leishmania antigen was detected only at 48 and 72 h post-infection. Messenger RNA from cytokines type 1 (IL-2, TNF-α, IFN-γ) and type 2 (IL-4, IL-10 and TGF-ß) detected by reverse transcriptase polymerase chain reaction and produced by spleen cells showed no qualitative difference between control non-infected hamsters and infected hamsters during any period of infection evaluated. Cytokines were measured by the DNA band intensity on agarose gel using the Image Lab 1D L340 software with no differences observed. In conclusion, the present results showed an antigen-dependent immunosuppression in hamsters with active visceral leishmaniasis that was not related to the cytokine profile.
Assuntos
Antígenos de Protozoários/imunologia , Citocinas/imunologia , Tolerância Imunológica/imunologia , Leishmania/imunologia , Leishmaniose Visceral/imunologia , Linfócitos T/imunologia , Animais , Proliferação de Células/efeitos dos fármacos , Cricetinae , Modelos Animais de Doenças , Masculino , Camundongos , Fator de Crescimento Transformador beta , Fatores de Crescimento Transformadores/imunologiaRESUMO
BACKGROUND: Comorbidity from tegumentary leishmaniasis and AIDS is poorly characterized. OBJECTIVES: To describe a series of patients coinfected with Leishmania and human immunodeficiency virus (HIV). METHODS: Clinical records from patients were analysed by demographic data, clinical manifestations, diagnoses, treatments and outcomes. RESULTS: Fifteen cases of AIDS/tegumentary leishmaniasis were found. The diagnosis of leishmaniasis was confirmed by the detection of Leishmania amastigotes or antigens from the cutaneous or mucosal lesions. The mean CD4+ T-cell count was 84 cells mm(-3) (range 8-258) and all patients were classified as having AIDS according to the Centers for Disease Control and Prevention. A wide range of manifestations was found, varying from a single ulcer to multiple and polymorphic lesions. Mucosal lesions were present in 80% and cutaneous lesions in 73% of patients (53% with mucocutaneous form), disseminated lesions in 60% and genital lesions in 27% of patients. All patients received anti-Leishmania therapy and 53% showed relapses. Sixty-seven per cent received highly active antiretroviral therapy but showed no difference in outcomes and relapses compared with those not using medication. Forty per cent died during the study period. In these patients, the anti-Leishmania antibody and Montenegro skin test were useful in the diagnosis of leishmaniasis, probably because leishmaniasis preceded immunosuppression due to HIV infection. CONCLUSIONS: Clinical manifestations of tegumentary leishmaniasis in HIV-infected patients are diverse. Our data emphasize possible unusual manifestations of this disease in HIV-infected patients, particularly in severely immunosuppressed cases (< 200 CD4+ cells mm(-3)).
Assuntos
Infecções Oportunistas Relacionadas com a AIDS/patologia , HIV-1 , Leishmaniose Cutânea/patologia , Mucosa/patologia , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Adulto , Contagem de Linfócito CD4 , Diagnóstico Diferencial , Métodos Epidemiológicos , Feminino , HIV-1/imunologia , Humanos , Hospedeiro Imunocomprometido , Leishmaniose Cutânea/imunologia , Masculino , Pessoa de Meia-Idade , Mucosa/imunologiaAssuntos
Infecções Oportunistas Relacionadas com a AIDS/imunologia , Leishmaniose/imunologia , Infecções Oportunistas Relacionadas com a AIDS/complicações , Animais , Relação CD4-CD8 , Citocinas/imunologia , Humanos , Imunidade Celular/imunologia , Interleucinas/imunologia , Leishmaniose/complicações , RNA Viral/sangue , Carga Viral , Replicação ViralRESUMO
Leishmaniasis is a disease caused by protozoa of the genus Leishmania, and visceral leishmaniasis is a form in which the inner organs are affected. Since knowledge about immunity in experimental visceral leishmaniasis is poor, we present here a review on immunity and immunosuppression in experimental visceral leishmaniasis in mouse and hamster models. We show the complexity of the mechanisms involved and differences when compared with the cutaneous form of leishmaniasis. Resistance in visceral leishmaniasis involves both CD4+ and CD8+ T cells, and interleukin (IL)-2, interferon (IFN)-gamma, and IL-12, the latter in a mechanism independent of IFN-gamma and linked to transforming growth factor (TGF)-beta production. Susceptibility involves IL-10 but not IL-4, and B cells. In immune animals, upon re-infection, the elements involved in resistance are different, i.e., CD8+ T cells and IL-2. Since one of the immunopathological consequences of active visceral leishmaniasis in humans is suppression of T-cell responses, many studies have been conducted using experimental models. Immunosuppression is mainly Leishmania antigen specific, and T cells, Th2 cells and adherent antigen-presenting cells have been shown to be involved. Interactions of the co-stimulatory molecule family B7-CTLA-4 leading to increased level of TGF-beta as well as apoptosis of CD4+ T cells and inhibition of macrophage apoptosis by Leishmania infection are other components participating in immunosuppression. A better understanding of this complex immune response and the mechanisms of immunosuppression in experimental visceral leishmaniasis will contribute to the study of human disease and to vaccine development.
Assuntos
Citocinas/imunologia , Leishmaniose Visceral/imunologia , Linfócitos T/imunologia , Fatores de Crescimento Transformadores/imunologia , Animais , Linfócitos B/imunologia , Cricetinae , Modelos Animais de Doenças , Terapia de Imunossupressão , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Leishmaniasis is a disease caused by protozoa of the genus Leishmania, and visceral leishmaniasis is a form in which the inner organs are affected. Since knowledge about immunity in experimental visceral leishmaniasis is poor, we present here a review on immunity and immunosuppression in experimental visceral leishmaniasis in mouse and hamster models. We show the complexity of the mechanisms involved and differences when compared with the cutaneous form of leishmaniasis. Resistance in visceral leishmaniasis involves both CD4+ and CD8+ T cells, and interleukin (IL)-2, interferon (IFN)-gamma, and IL-12, the latter in a mechanism independent of IFN-gamma and linked to transforming growth factor (TGF)-á production. Susceptibility involves IL-10 but not IL-4, and B cells. In immune animals, upon re-infection, the elements involved in resistance are different, i.e., CD8+ T cells and IL-2. Since one of the immunopathological consequences of active visceral leishmaniasis in humans is suppression of T-cell responses, many studies have been conducted using experimental models. Immunosuppression is mainly Leishmania antigen specific, and T cells, Th2 cells and adherent antigen-presenting cells have been shown to be involved. Interactions of the co-stimulatory molecule family B7-CTLA-4 leading to increased level of TGF-á as well as apoptosis of CD4+ T cells and inhibition of macrophage apoptosis by Leishmania infection are other components participating in immunosuppression. A better understanding of this complex immune response and the mechanisms of immunosuppression in experimental visceral leishmaniasis will contribute to the study of human disease and to vaccine development.
Assuntos
Cricetinae , Animais , Camundongos , Citocinas , Leishmaniose Visceral , Linfócitos T , Fatores de Crescimento Transformadores , Linfócitos B , Modelos Animais de Doenças , Terapia de Imunossupressão , Camundongos Endogâmicos BALB CRESUMO
Oxidative processes leading to the generation of oxidized low density lipoprotein (oxLDL) particles have been suggested to be an important factor in the pathogenesis of atherosclerosis. After initiation of the oxidative process, LDL undergoes a progressive protein and lipid fragmentation. To understand this process and the role of oxLDL in various diseases of inflammatory origin, we have generated mouse monoclonal antibodies against copper-oxidized human LDL. Mice were immunized intrasplenically and after one intravenous boost the spleen cells were fused with the Sp2/0 hybridoma fusion partner. The hybridoma clones obtained after selection and cloning were analyzed for reactivity against oxLDL with various degrees of copper-mediated oxidative modifications. Three hybridoma clones were purified and further characterized. The following observations were made: 1) the intrasplenic route of immunization, avoiding the use of mycobacterial adjuvants, yielded a high frequency of positive clones; 2) the individual hybridomas reacted against LDL with various degrees of oxidative modifications; 3) the monoclonal antibodies could be used in ELISA and to detect oxLDL in immunohistochemical tissue staining, and 4) the monoclonal antibodies also detected oxLDL from hamsters and rabbits. We conclude that these monoclonal antibodies could be useful to further investigate the role of oxLDL in inflammation and in the immune response.