Cytokine profile and pathology in human leishmaniasis

The clinical spectrum of leishmaniasis and control of the infection are influenced by the parasite-host relationship. The role of cellular immune responses of the Th1 type in the protection against disease in experimental and human leishmaniasis is well established. In humans, production of IFN-g is associated with the control of infection in children infected by Leishmania chagasi. In visceral leishmaniasis, an impairment in IFN-g production and high IL-4 and IL-10 levels (Th2 cytokines) are observed in antigen-stimulated peripheral blood mononuclear cells (PBMC). Moreover, IL-12 restores IFN-g production and enhances the cytotoxic response. IL-10 is the cytokine involved in down-regulation of IFN-g production, since anti-IL-10 monoclonal antibody (mAb) restores in vitro IFN-g production and lymphoproliferative responses, and IL-10 abrogates the effect of IL-12. In cutaneous and mucosal leishmaniasis, high levels of IFN-g are found in L. amazonensis-stimulated PBMC. However, low or absent IFN-g levels were observed in antigen-stimulated PBMC from 50% of subjects with less than 60 days of disease (24 ± 26 pg/ml). This response was restored by IL-12 (308 ± 342 pg/ml) and anti-IL-10 mAb (380 ± 245 pg/ml) (P<0.05). Later during the disease, high levels of IFN-g and TNF-a are produced both in cutaneous and mucosal leishmaniasis. After treatment there is a decrease in TNF-a levels (366 ± 224 pg/ml before treatment vs 142 ± 107 pg/ml after treatment, P = 0.02). Although production of IFN-g and TNF-a might be involved in the control of parasite multiplication in the early phases of Leishmania infection, these cytokines might also be involved in the tissue damage seen in tegumentary leishmaniasis

Mycobacterium leprae Recombinant Antigen Induces High Expression of Multifunction T Lymphocytes and Is Promising as a Specific Vaccine for Leprosy

Leprosy is a chronic disease caused by M. leprae infection that can cause severe neurological complications and physical disabilities. A leprosy-specific vaccine would be an important component within control programs but is still lacking. Given that multifunctional CD4 T cells [i.e., those capable of simultaneously secreting combinations of interferon (IFN)-γ, interleukin (IL)-2, and tumor necrosis factor (TNF)] have now been implicated in the protective response to several infections, we tested the hypothesis if a recombinant M. leprae antigen-specific multifunctional T cells differed between leprosy patients and their healthy contacts. We used whole blood assays and peripheral blood mononuclear cells to characterize the antigen-specific T cell responses of 39 paucibacillary (PB) and 17 multibacillary (MB) leprosy patients and 31 healthy household contacts (HHC). Cells were incubated with either crude mycobacterial extracts (M. leprae cell sonicate–MLCS) and purified protein derivative (PPD) or recombinant ML2028 protein, the homolog of M. tuberculosis Ag85B. Multiplex assay revealed antigen-specific production of IFN-γ and IL-2 from cells of HHC and PB, confirming a Th1 bias within these individuals. Multiparameter flow cytometry then revealed that the population of multifunctional ML2028-specific T cells observed in HHC was larger than that observed in PB patients. Taken together, our data suggest that these multifunctional antigen-specific T cells provide a more effective response against M. leprae infection that prevents the development of leprosy. These data further our understanding of M. leprae infection/leprosy and are instructive for vaccine development

Epidemiological characteristics and geographical distribution of schistosomiasis and geohelminths, in the State of Sergipe, according to data from the Schistosomiasis Control Program in Sergipe

INTRODUÇÃO: A esquistossomose é endêmica no Brasil, com elevada prevalência no Estado de Sergipe, apesar da existência do Programa de Controle da Esquistossomose (PCE). MÉTODOS: Foi realizado levantamento de dados do PCE-Sergipe de 2005 a 2008. A partir da matriz bruta formulou-se planilha de dados no software Access e analisou-se frequência e distribuição geográfica das infecções por Schistosoma mansoni e outros enteroparasitos. Estes dados foram exportados para o software Spring 5.0.5 para georreferenciamento e confecção de mapas temáticos de distribuição espacial e temporal por ano de avaliação. RESULTADOS: Foram positivos para S. mansoni 13,6% (14471/106287) de exames nos anos de 2005, 11,2% (16196/145069) em 2006, 11,8% (10220/86824) em 2007 e 10,6% (8329/78859) em 2008. A análise de mapas mostrou elevada prevalência da doença em Sergipe, em particular nos municípios Ilha das Flores, Santa Rosa de Lima, Santa Luzia do Itanhi e São Cristóvão. Além disso, avaliamos a associação entre as frequências dessas doenças parasitárias com indicadores sociais e de desenvolvimento dos diferentes municípios, de acordo com os dados do Instituto Brasileiro de Geografia e Estatística (IBGE) e da Superintendência de Recursos Hídricos (SRH). Observamos que os municípios com prevalência da esquistossomose maior do que 15% têm menor concentração de rede de esgotos (índice de higiene); p = 0,05. Adicionalmente, os municípios com prevalência de infecção por ancilostomídeos maior do que 10% apresentam um menor IDH educacional; p = 0,04. CONCLUSÕES: Ressalta-se a importância de maior controle dos fatores de risco ambientais e educacionais, na tentativa de reduzir prevalências dessas doenças parasitárias. ________________________________________________________________________________________ ABSTRACT: INTRODUCTION: Schistosomiasis is endemic in Brazil, with high prevalence in the State of Sergipe, despite the existence of the Schistosomiasis Control Program (PCE). METHODS: The data from Sergipe's PCE between 2005 and 2008 were surveyed. From the raw information, a database was created on a spreadsheet using the Access software. The frequency and geographic distribution of infections due to Schistosoma mansoni and other intestinal parasites were analyzed. These data were exported to the Spring 5.0.5 software for georeferencing and preparation of thematic maps of the spatial and temporal distribution according to year of evaluation. RESULTS: In 2005, 13.6% (14,471/106,287) of the tests were positive for S. mansoni, 11.2% (16,196/145,069) in 2006, 11.8% (10,220/86,824) in 2007 and 10.6% (8,329/78,859) in 2008. Analysis on the maps showed that there was high prevalence of the disease in Sergipe, and particularly in the municipalities of Ilha das Flores, Santa Rosa de Lima, Santa Luzia do Itanhi and São Cristóvão. Furthermore, we evaluated the association between the frequencies of these parasitic diseases and social and developmental indicators in the different municipalities, according to data from the Brazilian Institute for Geography and Statistics (IBGE) and the Department of Water Resources (SRH). We found that municipalities with schistosomiasis prevalence higher than 15% had lower coverage of sewage systems (hygiene index) (p = 0.05). Additionally, municipalities with hookworm prevalence higher than 10% had lower educational HDI (p = 0.04). CONCLUSIONS: The importance of greater control over environmental risk and educational factors needs to be emphasized in attempts to reduce the prevalence of these parasitic diseases

Effect of periodontal therapy on metabolic control and levels of IL-6 in the gingival crevicular fluid in type 2 diabetes mellitus

Background: The aim of this study was to compare the efficacy of metabolic control and levels of interleukin 6 (IL-6) in gingival crevicular fluid after periodontal therapy in type 2 diabetes mellitus (DM) and nondiabetic (NDM) patients. Methods: This study was performed in 20 subjects (10 type 2 DM and 10 NDM patients with generalized chronic periodontal disease. Both groups were recorded for clinical parameters (plaque index (PI), gingival index (GI), probing depth (PD), gingival recession (GR) and clinical attachment level (CAL)), metabolic control (fasting glucose levels, glycated a-hemoglobin (HbA1c), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TR)), and IL-6 levels at baseline and 3 months after periodontal treatment. Results: DM and NDM patients revealed significant statistical reductions for clinical parameters (P < 0.05, RM ANOVA) after 3 months. DM group had improvements on HbA1c and had significant statistical increased of TRG (P < 0.05, RM ANOVA) after 3 months. No differences of LDL/HDL and IL-6 levels were found after 3 months in both groups. Conclusion: DM group presented a significant reduction of HbA1c levels after periodontal therapy. However, TRG levels increased after 3 months, which suggest more confirmatory studies to investigate if these results will be repeated in other studies

CD4+ Th1 and Th17 responses and multifunctional CD8 T lymphocytes associated with cure or disease worsening in human visceral leishmaniasis

IntroductionIn VL, a proinflammatory phenotype is typically associated with enhanced phagocytosis and a Th1 mediated immune response resulting in infection control. In contrast, an anti-inflammatory phenotype, associated with a predominant regulatory response, typically enables intracellular multiplication of Leishmania parasites and disease progression.MethodsTo investigate the impact of chemotherapy on Th2 and Th17 immune responses in patients with visceral leishmaniasis (VL), we assessed all combinations of intracellular expression of IFN-γ, IL-10, IL-4 and IL-17 in the CD4+ and CD8+ T cell populations of peripheral blood mononuclear cell (PBMC) samples from patients, after antigenic stimulation with Leishmania lysate, throughout treatment and follow-up. As increases in spleen and liver sizes and decreases in hematocrit, hemogloblin, erythrocytes, monocytes, leukocytes and platelets levels are strongly related to the disease, we studied the correlations between the frequencies of T cells producing the afore mentioned cytokines, individually and in combination, and these variables, as markers of disease or cure.ResultsWe found that the frequency of IFN-γ-producingCD4+ T cells increased until the end of chemotherapy with Glucantime® or AmBisome ®, while IL-10, IL-4 and IL-17-producing CD4+ T cells peaked on day 7 following the start of treatment. Although the frequency of CD4+IL-17+ cells decreased during treatment an increase was observed after clinical cure. The frequency of CD4+ T cells producing only IFN-γ or IL-17 correlated with blood monocytes levels. Frequencies of double-producers of IFN-γ and IL-10 or IL-4 correlated positively with eosinophils and platelets levels. Together, this suggest that IFN-γ drives the immune response towards Th1 at cure. In contrast, and associated with disease or Th2 response, the frequency of CD4+ IL-10+ cells correlated positively with spleen sizes and negatively with circulating monocyte levels, while the frequency of CD4+ producing both IL-4 and IL-10 correlated negatively with platelets levels. The frequency of CD8+ single-producers of IFN-γ increased from day 21 to 90 while that of single-producers of IL-10 peaked on day 7, of IL-4 on day 30 and of IL-17, on day 180. IFN-γ expression in CD8+ single- and double-producers of cytokines was indicative of an immune response associated with cure. In contrast, frequencies of CD8+ double-producers of IL-4 and IL-10, IL-4 and IL-17 and IL-10 and IL-17 and producers of three and four cytokines, were associated with disease and were low after the cure. Frequencies of CD8+ T cells producing IFN-γ alone or with IL-17 were positively correlated with platelets levels. In contrast, as markers of disease: 1) frequencies of single producers of IL-10 correlated negatively with leukocytes levels, 2) frequencies of double producers of IL-4 and IL-10 correlated negatively with platelet, leukocyte, lymphocyte and circulating monocyte levels, 3) frequencies of triple-producers of IFN-γ, IL-4 and IL-10 correlated negatively with platelet, leukocyte and neutrophil levels and 4) frequencies of producers of IFN-γ, IL-4, IL-10 and IL-17 simultaneously correlated positively with spleen size, and negatively with leukocyte and neutrophil levels.DiscussionOur results confirmed that the clinical improvement of VL patients correlates with the decrease of an IL-4 and IL-10 CD4+Th2 response, the recovery of CD4+ Th1 and Th17 responses and the frequency of CD8+ single-producers of IFN-γ and double producers of IFN-γ and IL-17

Differential effects of antigens from L. braziliensis isolates from disseminated and cutaneous leishmaniasis on in vitro cytokine production

BACKGROUND: Disseminated leishmaniasis is an emerging infectious disease, mostly due to L. braziliensis, which has clinical and histopathological features distinct from cutaneous leishmaniasis. METHODS: In the current study we evaluated the in vitro production of the cytokines IFN-γ, TNF-α, IL-5 and IL-10 by peripheral blood mononuclear cells (PBMC) from 15 disseminated leishmaniasis and 24 cutaneous leishmaniasis patients upon stimulation with L. braziliensis antigens genotyped as disseminated leishmaniasis or cutaneous leishmaniasis isolates. RESULTS: Regardless of the source of L. braziliensis antigens, PBMC from cutaneous leishmaniasis patients produced significantly higher IFN-γ than PBMC from disseminated leishmaniasis patients. Levels of TNF-α by PBMC from cutaneous leishmaniasis patients were significantly higher than disseminated leishmaniasis patients only when stimulated by genotyped cutaneous leishmaniasis antigens. The levels of IL-5 and IL-10 production by PBMC were very low and similar in PBMCs from both disseminated leishmaniasis and cutaneous leishmaniasis patients. The immune response of each patient evaluated by the two L. braziliensis antigens was assessed in a paired analysis in which we showed that L. braziliensis genotyped as disseminated leishmaniasis isolate was more potent than L. braziliensis genotyped as cutaneous leishmaniasis isolate in triggering IFN-γ and TNF-α production in both diseases and IL-5 only in cutaneous leishmaniasis patients. CONCLUSION: This study provides evidence that antigens prepared from genotypically distinct strains of L. braziliensis induce different degrees of immune response. It also indicates that both parasite and host play a role in the outcome of L. braziliensis infection