RESUMO
Background: Chronic periodontitis (CP), caused by bacteria and fungi, appears in up to 66% of HIV-patients. The impact and association of HIV-treatment (HAART) and Candida itself has not been properly evaluated in the development and progression of CP. The immunopathogenesis is characterized by CD4+ T-cells activation and the balance between the T-helper 1 (Th1) and T-helper 2 (Th2) or a mixed cytokine profile. Currently, the associated causes of an immune response in HIV-patients with CP is controversial. Our aims were the determination of Candida spp. and cytokine profile in oral samples from HIV-positive patients with CP, considering the CD4+ T cells levels and HAART use. Methods: From 500 HIV-positive patients evaluated, 228 patients were enrolled. Patients were separated in groups: (A) n = 53 (≤200 CD4+ T-cells on HAART); (B) n = 57 (≤200 CD4+ T-cells without HAART); (C) n = 50 (>200 CD4+ T-cells without HAART); (D) n = 68 (>200 CD4+ T-cells on HAART). Candida spp. were isolated from the oral biofilm and crevicular fluid in CHROMagar and confirmed by endpoint PCR. Cytokine levels were measured by beads-based immunoassay in saliva by flow cytometry. Results: 147 patients (64.5%) were positive to Candida spp. and 204 strains were isolated; 138 (67.6%) were C. albicans and the remaining C. non-albicans species (C. glabrata>C. tropicalis>C. krusei>C. dubliniensis). In this study, CHROMagar showed good sensitivity (95%) but poor specificity (68%); since of the 152 samples identified as C. albicans, only 131 were confirmed by PCR; from the 10 samples identified as C. glabrata, only six were confirmed. Finally, of the 42 samples detected as C. tropicalis, only five were confirmed. When evaluating Candida spp. presence, group A and D had higher isolation, while group B had the highest species diversity. Whereas, group C had a significant reduction of Candida spp. Despite the presence of Candida and HAART, we found a Th1/Th2 hybrid profile in the saliva of patients with low CD4+ T-cell count (group A). Conclusion: Abundance and diversity of the Candida spp. detected in HIV-patients with CP could be related to HAART and low CD4+ T-cells levels. Also, the immunosuppression might promote a local Th1/Th2 hybrid cytokine profile.
Assuntos
Candida/imunologia , Candidíase Bucal/imunologia , Periodontite Crônica/imunologia , Citocinas/imunologia , Infecções por HIV/imunologia , Células Th1/imunologia , Células Th2/imunologia , Adulto , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Candida/classificação , Candida/fisiologia , Candidíase Bucal/microbiologia , Periodontite Crônica/microbiologia , Periodontite Crônica/virologia , Citocinas/metabolismo , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Saliva/efeitos dos fármacos , Saliva/imunologia , Saliva/metabolismo , Especificidade da Espécie , Células Th1/microbiologia , Células Th1/virologia , Células Th2/microbiologia , Células Th2/virologiaRESUMO
OBJECTIVE: This study aimed to determine whether Mycobacterium bovis Bacillus Calmette-Guérin (BCG) treatment can reverse an established allergic airway inflammation in a BALB/c mouse model of ovalbumin (OVA)-induced airway inflammation. METHODS: OVA sensitized BALB/c mice were challenged with aerosolized OVA on days 28 to 30, 34, 41 and 63. Mice were intranasal treated with BCG on days 35 and 42. Twenty-four hours after the last challenge, blood samples were collected to detect anti-OVA immunoglobulin isotypes, and bronchoalveolar lavage (BAL) was harvested for cell count. Additionally, lungs were collected for histological analysis, detection of the eosinophil peroxidase (EPO) activity and measurement of cytokines and CCL11. The expression of CTLA-4, Foxp3 and IL-10 was also determined in lung tissue by flow cytometry. RESULTS: BCG treatment was able to inhibit an established allergic Th2-response, by decreasing the allergen-induced eosinophilic inflammation, EPO activity, levels of CCL11 and IL-4, serum levels of IgE and IgG1. Mycobacteria treatment increased lung levels of IFN-γ, IL-10 and TGF-ß, and expressions of Foxp3 and CTLA-4 in CD4(+)T cells. Additionally, an increased production of IL-10 by CD8(+) T cells was observed, even though no detectable changes in CD4(+)IL-10(+) was noticed. CONCLUSION: BCG treatment inhibits features of allergic airway inflammation and the results suggest that the mechanism underlying the down-regulatory effects of BCG on OVA-induced airway inflammation appear to be associated with the induction of both Th1 and T regulatory immune responses.
Assuntos
Antialérgicos/administração & dosagem , Vacina BCG/administração & dosagem , Regulação para Baixo/imunologia , Mycobacterium bovis/imunologia , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Hipersensibilidade Respiratória/imunologia , Células Th2/imunologia , Animais , Antialérgicos/imunologia , Vacina BCG/imunologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Feminino , Imunoglobulina E/biossíntese , Imunoglobulina G/biossíntese , Inflamação/microbiologia , Inflamação/patologia , Inflamação/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Hipersensibilidade Respiratória/patologia , Hipersensibilidade Respiratória/prevenção & controle , Células Th2/efeitos dos fármacos , Células Th2/microbiologiaRESUMO
Leprosy is not eradicable with currently available diagnostics or interventions, as evidenced by its stable incidence. Early diagnosis of Mycobacterium leprae infection should therefore be emphasized in leprosy research. It remains challenging to develop tests based on immunological biomarkers that distinguish individuals controlling bacterial replication from those developing disease. To identify biomarkers for field-applicable diagnostics, we determined cytokines/chemokines induced by M. leprae proteins in blood of leprosy patients and endemic controls (EC) from high leprosy-prevalence areas (Bangladesh, Brazil, Ethiopia) and from South Korea, where leprosy is not endemic anymore. M. leprae-sonicate-induced IFN-γ was similar for all groups, excluding M. leprae/IFN-γ as a diagnostic readout. By contrast, ML2478 and ML0840 induced high IFN-γ concentrations in Bangladeshi EC, which were completely absent for South Korean controls. Importantly, ML2478/IFN-γ could indicate distinct degrees of M. leprae exposure, and thereby the risk of infection and transmission, in different parts of Brazilian and Ethiopian cities. Notwithstanding these discriminatory responses, M. leprae proteins did not distinguish patients from EC in one leprosy-endemic area based on IFN-γ. Analyses of additional cytokines/chemokines showed that M. leprae and ML2478 induced significantly higher concentrations of MCP-1, MIP-1ß, and IL-1ß in patients compared with EC, whereas IFN-inducible protein-10, like IFN-γ, differed between EC from areas with dissimilar leprosy prevalence. This study identifies M. leprae-unique Ags, particularly ML2478, as biomarker tools to measure M. leprae exposure using IFN-γ or IFN-inducible protein-10, and also shows that MCP-1, MIP-1ß, and IL-1ß can potentially distinguish pathogenic immune responses from those induced during asymptomatic exposure to M. leprae.
Assuntos
Citocinas/sangue , Hanseníase/epidemiologia , Hanseníase/imunologia , Mycobacterium leprae/imunologia , Adulto , Idoso , Antígenos de Bactérias/imunologia , Bangladesh/epidemiologia , Biomarcadores/sangue , Brasil/epidemiologia , Citocinas/biossíntese , Citocinas/genética , Etiópia/epidemiologia , Feminino , Humanos , Interferon gama/biossíntese , Interferon gama/sangue , Interferon gama/genética , Hanseníase/diagnóstico , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Células Th1/imunologia , Células Th1/microbiologia , Células Th2/imunologia , Células Th2/microbiologia , Adulto JovemRESUMO
Mycobacterium bovis Bacillus Calmette-Guerin (BCG) has been shown to down-regulate experimental allergic asthma, a finding that reinforced the hygiene hypothesis. We have previously found that recombinant BCG (rBCG) strain that express the genetically detoxified S1 subunit of pertussis toxin (rBCG-S1PT) exerts an adjuvant effect that enhances Th1 responses against BCG proteins. Here we investigated the effect of this rBCG-S1PT on the classical ovalbumin-induced mouse model of allergic lung disease. We found that rBCG-S1PT was more effective than wild-type BCG in preventing Th2-mediated allergic immune responses. The inhibition of allergic lung disease was not associated with increased concentration of suppressive cytokines or with an increased number of pulmonary regulatory T cells but was positively correlated with the increase in IFN-gamma-producing T cells and T-bet expression in the lung. In addition, an IL-12-dependent mechanism appeared to be important to the inhibition of lung allergic disease. The inhibition of allergic inflammation was found to be restricted to the lung because when allergen challenge was given by the intraperitoneal route, rBCG-S1PT administration failed to inhibit peritoneal allergic inflammation and type 2 cytokine production. Our work offers a nonclassical interpretation for the hygiene hypothesis indicating that attenuation of lung allergy by rBCG could be due to the enhancement of local lung Th1 immunity induced by rBCG-S1PT. Moreover, it highlights the possible use of rBCG strains as multipurpose immunomodulators by inducing specific immunity against microbial products while protecting against allergic asthma.
Assuntos
Hipersensibilidade/microbiologia , Mycobacterium bovis/imunologia , Mycobacterium bovis/metabolismo , Células Th1/microbiologia , Animais , Citocinas/metabolismo , Eosinófilos/microbiologia , Feminino , Interferon gama/metabolismo , Interleucina-12/genética , Interleucina-12/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Ovalbumina/metabolismo , Proteínas Recombinantes/metabolismo , Células Th2/microbiologiaRESUMO
The kinetics of macrophage and T lymphocyte apoptosis were determined in a well-characterized mouse model of pulmonary tuberculosis, comparing strains of intermediate (H37Rv) and high virulence (Beijing strain, code 9501000). Both strains induced a high percentage of apoptotic activated macrophages at days 1 and 3 post infection, although this was twofold lower in Beijing-infected mice. Progressive pneumonia started at day 14 (Beijing) or 21 (H37Rv) post infection. Pneumonic areas contained numerous macrophages with vacuolated cytoplasm (VM). In H37Rv infection few VM were apoptotic (8.7% at day 60), and the percentage was even lower in Beijing infection (1.4% at day 28). A high percentage of VM expressed the anti-apoptotic molecule Bcl-2 (H37Rv, 83%; Beijing, 95%). Both strains induced a progressive increase of apoptotic Th1 lymphocytes, peaking at day 60 in H37Rv infection, or 28 in Beijing infection. The peak was twofold higher in the latter. VM had strong FasL immunostaining, and confocal microscopy showed numerous apoptotic Th1 cells closely associated with them, suggesting that VM might induce apoptosis of Th1 cells. These results support the hypothesis that apoptosis of macrophages is associated with protection, while apoptosis of Th1 cells favors disease progression, and is related to the virulence of the mycobacterial strain.