Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 123
Filtrar
1.
J Vis Exp ; (195)2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37246862

RESUMO

Experimental autoimmune encephalomyelitis (EAE) induced by myelin oligodendrocyte glycoprotein (MOG) requires immunization by a MOG peptide emulsified in complete Freund's adjuvant (CFA) containing inactivated Mycobacterium tuberculosis. The antigenic components of the mycobacterium activate dendritic cells to stimulate T-cells to produce cytokines that promote the Th1 response via toll-like receptors. Therefore, the amount and species of mycobacteria present during the antigenic challenge are directly related to the development of EAE. This methods paper presents an alternative protocol to induce EAE in C57BL/6 mice using a modified incomplete Freund's adjuvant containing the heat-killed Mycobacterium avium subspecies paratuberculosis strain K-10. M. paratuberculosis, a member of the Mycobacterium avium complex, is the causative agent of Johne's disease in ruminants and has been identified as a risk factor for several human T-cell-mediated disorders, including multiple sclerosis. Overall, mice immunized with Mycobacterium paratuberculosis showed earlier onset and greater disease severity than mice immunized with CFA containing the strain of M. tuberculosis H37Ra at the same doses of 4 mg/mL. The antigenic determinants of Mycobacterium avium subspecies paratuberculosis (MAP) strain K-10 were able to induce a strong Th1 cellular response during the effector phase, characterized by significantly higher numbers of T-lymphocytes (CD4+ CD27+), dendritic cells (CD11c+ I-A/I-E+), and monocytes (CD11b+ CD115+) in the spleen compared to mice immunized with CFA. Furthermore, the proliferative T-cell response to the MOG peptide appeared to be highest in M. paratuberculosis-immunized mice. The use of an encephalitogen (e.g., MOG35-55) emulsified in an adjuvant containing M. paratuberculosis in the formulation may be an alternative and validated method to activate dendritic cells for priming myelin epitope-specific CD4+ T-cells during the induction phase of EAE.


Assuntos
Encefalomielite Autoimune Experimental , Mycobacterium avium subsp. paratuberculosis , Paratuberculose , Camundongos , Humanos , Animais , Encefalomielite Autoimune Experimental/etiologia , Autoantígenos , Paratuberculose/complicações , Camundongos Endogâmicos C57BL , Adjuvantes Imunológicos , Glicoproteína Mielina-Oligodendrócito , Peptídeos
2.
Nutrients ; 15(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36678131

RESUMO

Folate and vitamin B12 deficiency is highly prevalent among Crohn's disease (CD) patients. Furthermore, CD pathology can be mediated by Mycobacterium avium subsp. paratuberculosis (MAP) infection. However, the direct effect of folate (B9) and cobalamin (B12) deficiency during MAP infection remains uncharacterized. This study investigates how folate and B12 deficiency impedes macrophage apoptosis and exacerbates the inflammation in macrophages infected with MAP isolated from CD patients. Accordingly, we measured folate and B12 in ex vivo plasma samples collected from CD patients with or without MAP infection (N = 35 per group). We also measured the expression of the pro-inflammatory cytokines IL-1ß and TNF-α, cellular apoptosis and viability markers, and bacterial viability in MAP-infected macrophages cultured in folate and B12 deficient media. We determined that MAP-positive CD patients have significantly lower plasma folate and B12 in comparison to MAP-negative CD patients [414.48 ± 94.60 pg/mL vs. 512.86 ± 129.12 pg/mL, respectively]. We further show that pro-inflammatory cytokines IL-1ß and TNF-α are significantly upregulated during folate and vitamin B12 deprivation following MAP infection by several folds, while supplementation significantly reduces their expression by several folds. Additionally, depletion of folate, B12, and folate/B12 following MAP infection, led to decreased macrophage apoptosis from 1.83 ± 0.40-fold to 1.04 ± 0.08, 0.64 ± 0.12, and 0.45 ± 0.07 in folate-low, B12-low, and folate/B12-low cells, respectively. By contrast, folate and folate/B12 supplementation resulted in 3.38 ± 0.70 and 2.58 ± 0.14-fold increases in infected macrophages. Interestingly, changes in overall macrophage viability were only observed in folate-high, folate/B12-high, and folate/B12-low media, with 0.80 ± 0.05, 0.82 ± 0.02, and 0.91 ± 0.04-fold changes, respectively. Incubation of Caco-2 intestinal epithelial monolayers with supernatant from infected macrophages revealed that folate/B12 deficiency led to increased LDH release independent of oxidative stress. Overall, our results indicate that folate and B12 are key vitamins affecting cell survival and inflammation during MAP infection.


Assuntos
Doença de Crohn , Deficiência de Ácido Fólico , Paratuberculose , Deficiência de Vitamina B 12 , Humanos , Células CACO-2 , Doença de Crohn/complicações , Doença de Crohn/microbiologia , Citocinas , Ácido Fólico , Inflamação , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/complicações , Fator de Necrose Tumoral alfa , Vitamina B 12 , Vitaminas , Deficiência de Vitamina B 12/complicações , Deficiência de Ácido Fólico/complicações
3.
Front Immunol ; 12: 714179, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421917

RESUMO

This article prosecutes a case against the zoonotic pathogen Mycobacterium avium ss. paratuberculosis (MAP) as a precipitant of Alzheimer's disease (AD). Like the other major neurodegenerative diseases AD is, at its core, a proteinopathy. Aggregated extracellular amyloid protein plaques and intracellular tau protein tangles are the recognized protein pathologies of AD. Autophagy is the cellular housekeeping process that manages protein quality control and recycling, cellular metabolism, and pathogen elimination. Impaired autophagy and cerebral insulin resistance are invariant features of AD. With a backdrop of age-related low-grade inflammation (inflammaging) and heightened immune risk (immunosenescence), infection with MAP subverts glucose metabolism and further exhausts an already exhausted autophagic capacity. Increasingly, a variety of agents have been found to favorably impact AD; they are agents that promote autophagy and reduce insulin resistance. The potpourri of these therapeutic agents: mTOR inhibitors, SIRT1 activators and vaccines are seemingly random until one recognizes that all these agents also suppress intracellular mycobacterial infection. The zoonotic mycobacterial MAP causes a common fatal enteritis in ruminant animals. Humans are exposed to MAP from contaminated food products and from the environment. The enteritis in animals is called paratuberculosis or Johne's disease; in humans, it is the putative cause of Crohn's disease. Beyond Crohn's, MAP is associated with an increasing number of inflammatory and autoimmune diseases: sarcoidosis, Blau syndrome, autoimmune diabetes, autoimmune thyroiditis, multiple sclerosis, and rheumatoid arthritis. Moreover, MAP has been associated with Parkinson's disease. India is one county that has extensively studied the human bio-load of MAP; 30% of more than 28,000 tested individuals were found to harbor, or to have harbored, MAP. This article asserts an unfolding realization that MAP infection of humans 1) is widespread in its presence, 2) is wide-ranging in its zoonosis and 3) provides a plausible link connecting MAP to AD.


Assuntos
Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Suscetibilidade a Doenças , Imunossenescência , Inflamação/complicações , Resistência à Insulina , Paratuberculose/complicações , Doença de Alzheimer/patologia , Proteínas Amiloidogênicas/química , Proteínas Amiloidogênicas/metabolismo , Animais , Autofagia , Biomarcadores , Humanos , Mycobacterium avium subsp. paratuberculosis , Mycobacterium bovis/imunologia , Paratuberculose/imunologia , Paratuberculose/microbiologia
4.
Sci Rep ; 9(1): 6282, 2019 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-31000760

RESUMO

Recent evidence points at the role that human endogenous retroviruses (HERVs) may play through the activation of genes integrated across the human genome. Although a variety of genetic/epigenetic mechanisms maintain most HERVs silenced, independent environmental stimuli including infections may transactivate endogenous elements favoring pathogenic conditions. Several studies associated exposures to Mycobacterium avium subsp. paratuberculosis (MAP) with increased anti-MAP seroreactivity in T1D patients. Here, we assessed humoral responses against HERV envelope antigens (HERV-KEnv and HERV-WEnv) and four MAP-derived peptides with human homologs in distinct populations: Sardinian children at T1D risk (rT1D) (n = 14), rT1D from mainland Italy (n = 54) and Polish youths with T1D (n = 74) or obesity unrelated to autoimmunity (OB) (n = 26). Unlike Sardinian rT1D, youths displayed increased anti-HERV-WEnv Abs prevalence compared to age-matched OB or healthy controls (24.32 vs. 11.54%, p = 0.02 for Polish T1D/OB and 31.48 vs. 11.90%, p = 0.0025 for Italian rT1D). Anti-HERV-KEnv responses showed variable trends across groups. A strong correlation between Abs levels against HERV-WEnv and homologous peptides was mirrored by time-related Abs patterns. Elevated values registered for HERV-WEnv overlaped with or preceded the detection of T1D diagnostic autoantibodies. These results support the hypothesis of MAP infection leading to HERV-W antigen expression and enhancing the production of autoantibodies in T1D.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Retrovirus Endógenos/imunologia , Mycobacterium avium subsp. paratuberculosis/imunologia , Paratuberculose/imunologia , Adolescente , Anticorpos Anti-Idiotípicos/sangue , Anticorpos Anti-Idiotípicos/imunologia , Autoanticorpos/genética , Autoanticorpos/imunologia , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/virologia , Retrovirus Endógenos/genética , Epitopos/genética , Epitopos/imunologia , Feminino , Produtos do Gene env/genética , Produtos do Gene env/imunologia , Genoma Humano/genética , Humanos , Itália , Masculino , Mycobacterium avium subsp. paratuberculosis/patogenicidade , Paratuberculose/sangue , Paratuberculose/complicações , Paratuberculose/virologia , Peptídeos/genética , Peptídeos/imunologia , Proteínas da Gravidez/genética , Proteínas da Gravidez/imunologia , Ativação Transcricional/imunologia
5.
Can J Vet Res ; 81(2): 155-159, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28408784

RESUMO

Infection with small ruminant lentiviruses (SRLV) causes a variety of chronic inflammatory conditions that limit production. Mycobacterium avium subsp. paratuberculosis (MAP) is also a major production-limiting disease of sheep and goats, which causes severe inflammation of the small intestine. Previous studies have indicated that both SRLV and MAP are widespread in small ruminants in Ontario. This study estimated the prevalence of SRLV and MAP co-infection. Serum samples that were previously tested for MAP infection were re-tested for SRLV. The apparent prevalence of co-infection was low, with 3.4% [95% confidence interval (CI): 1.9 to 5.9] and 14.3% (95% CI: 11.6 to 17.5) of sheep and goats respectively, positive for both infections. However, co-infection is widespread with 36.8% (95% CI: 19.1 to 59.1) and 71.4% (95% CI: 52.8 to 84.9) of sheep and goat farms with 1 or more co-infected animals. A significant association was found between SRLV seropositivity and MAP fecal culture (P = 0.021), suggesting that co-infected goats may be more likely to shed MAP in their feces.


L'infection par lentivirus des petits ruminants (SRLV) provoque une variété d'états inflammatoires chroniques qui limitent la production. Mycobacterium avium subsp. paratuberculose (MAP) est aussi une maladie limitant la production majeure de moutons et de chèvres, ce qui provoque une inflammation grave de l'intestin grêle. Des études antérieures ont indiqué que les deux infections de SRLV et MAP sont très répandues dans l'Ontario petits ruminants. Cette étude a été réalisée pour estimer la prévalence de SRLV et MAP co-infection. Des échantillons de sérum qui avaient été préalablement testés pour l'infection de MAP ont été utilisés pour détecter des anticorps spécifiques SLRV. La prévalence de la co-infection était faible, avec 3,4 % intervalle de confiance (95% IC : 1,9­5,9) et 14,3 % (95% IC : 11,6­17,5) des ovins et caprins, respectivement, positive pour les deux infections. Cependant la co-infection est très répandue avec 36,8 % (95% IC : 19,1­59,1) et 71,4 % (95% IC : 52,8­84,9) des élevages ovins et caprins avec un ou plusieurs animaux co-infecté. Une association significative a été trouvée entre SRLV et séropositivité MAP culture fécale (P = 0,021), ce qui suggère que les chèvres co-infectés peuvent être plus susceptibles de jeter le MAP dans leurs excréments.(Traduit par les auteurs).


Assuntos
Doenças das Cabras/epidemiologia , Infecções por Lentivirus/veterinária , Lentivirus Ovinos-Caprinos/isolamento & purificação , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/complicações , Doenças dos Ovinos/epidemiologia , Animais , Estudos Transversais , Doenças das Cabras/microbiologia , Doenças das Cabras/virologia , Cabras , Infecções por Lentivirus/complicações , Infecções por Lentivirus/epidemiologia , Infecções por Lentivirus/virologia , Ontário/epidemiologia , Paratuberculose/diagnóstico , Paratuberculose/epidemiologia , Ovinos , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/virologia
6.
J Infect Dev Ctries ; 10(8): 857-62, 2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27580332

RESUMO

INTRODUCTION: Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of paratuberculosis or Johne's disease in ruminants. Its role in triggering autoimmunity, including type 1 diabetes mellitus (T1DM), has been reported in recent years. Due to the high contamination rate of MAP in Iran's livestock and the increasing outbreak of T1DM, we investigated this association in a small group of patients with T1DM in Iran. METHODOLOGY: Blood samples of 29 T1DM patients and 29 healthy control subjects were tested through enzyme-linked immunosorbent assay (ELISA) to detect antibodies against MAP3865c and ZnT8 homologous epitopes and the presence of MAP DNA. Blood samples were also cultured in mycobacterial growth indicator tubes and Herrold's egg yolk medium containing mycobactin J. RESULTS: The results of ELISA showed a significant difference between T1DM patients and healthy group. IS900 was also detected in 51.72% of T1DM patients but in none of the control group. None of the samples grew in culture media. CONCLUSIONS: Due to the presence of MAP DNA and antibodies against MAP peptides in a significant number of T1DM patients compared with healthy control subjects, we may consider MAP as a possible trigger of T1DM in Iran. This indicates that exposure to MAP occurred in the positive subjects. Identifying the sources of contamination and routes of MAP transmission to humans seems necessary to prevent and reduce the burden of MAP infection in Iran.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Testes Diagnósticos de Rotina/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/complicações , Paratuberculose/epidemiologia , Reação em Cadeia da Polimerase/métodos , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Sangue/imunologia , Sangue/microbiologia , Criança , Pré-Escolar , DNA Bacteriano/sangue , Diabetes Mellitus Tipo 1/etiologia , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Técnicas Microbiológicas , Mycobacterium avium subsp. paratuberculosis/genética , Mycobacterium avium subsp. paratuberculosis/imunologia , Adulto Jovem
7.
J Mol Neurosci ; 60(1): 91-3, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27370541

RESUMO

B cells are being recognized as one of the major players in the pathogenesis of multiple sclerosis (MS). The B cell activating factor (BAFF) system plays an essential role in B cell homeostasis and function in the periphery. Mycobacterium avium subspecies paratuberculosis (MAP) has been previously associated to MS in Sardinia. Antibodies against a MAP surface protein, MAP_2694, have been found significantly associated to MS patients, and this response was modified by interferon-ß therapy. Increased BAFF levels following IFN-ß therapy have been also described in MS patients. In this study, we evaluated whether soluble BAFF levels are comparable in men and women affected by MS and performed a correlation of the reported BAFF increase in MS patients under IFN-ß therapy with changes of humoral response against MAP_2694. For these reasons, we investigated 44 MS patients before and after IFN-ß therapy. A significant difference of BAFF levels was found between men and women with MS; moreover, we confirmed that IFN-ß therapy strongly induces BAFF serum levels, but this was not related to the modification of immunological response against MAP_2694. In conclusion, our study highlights that IFN-ß therapy induces the potent B cell survival factor BAFF without alterations of the humoral immune response against MAP.


Assuntos
Fator Ativador de Células B/sangue , Fatores Imunológicos/uso terapêutico , Interferon beta/uso terapêutico , Esclerose Múltipla/sangue , Mycobacterium avium/imunologia , Paratuberculose/sangue , Adulto , Anticorpos Antibacterianos/sangue , Estudos de Casos e Controles , Feminino , Humanos , Fatores Imunológicos/efeitos adversos , Interferon beta/efeitos adversos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Esclerose Múltipla/tratamento farmacológico , Paratuberculose/complicações
8.
Inflamm Bowel Dis ; 22(7): 1755-62, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27104824

RESUMO

Besides genetics and environmental factors, intestinal microbiota seem to play a major role in the pathogenesis of inflammatory bowel diseases. For many decades, it has been said that some enteropathogens may even trigger both inflammatory bowel disease development and disease flares. For this reason, stool testing had been performed in inflammatory bowel disease flares but current guidelines only recommend to rule out Clostridium difficile infection and there is no clear advice for other enteropathogens given that the scarce available evidence points at a low prevalence of this sort of intestinal superinfections with no clear impact on disease course. The present article reviews the current knowledge about the role of bacterial enteropathogens on disease pathogenesis and flares beyond C. difficile.


Assuntos
Doenças Inflamatórias Intestinais/microbiologia , Superinfecção/microbiologia , Aeromonas , Infecções por Campylobacter/complicações , Infecções por Chlamydia/complicações , Infecções por Escherichia coli/complicações , Humanos , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/tratamento farmacológico , Listeria monocytogenes , Listeriose/complicações , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/complicações , Fatores de Risco , Infecções por Salmonella/complicações , Superinfecção/complicações , Superinfecção/tratamento farmacológico , Yersiniose/complicações
9.
PLoS One ; 11(3): e0152063, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27019109

RESUMO

BACKGROUND: Association of Mycobacterium avium subspecies paratuberculosis (MAP) and Crohn's disease (CD) has been controversial due to contradictory reports. Therefore, we determined the prevalence of MAP in patients with CD and intestinal tuberculosis (ITB) and its association with clinical course. METHODOLOGY: Blood and intestinal biopsies were taken from 69 CD, 32 ITB patients and 41 patients with haemorrhoidal bleed who served as controls. qPCR targeting of MAP-specific IS900 gene was used to detect the presence of MAP DNA. qPCR results were further validated by sequencing. Immunohistochemistry (IHC) was used to detect the presence of MAP antigen in biopsy specimens. CD and ITB patients were followed-up for disease course and response to therapy. PRINCIPAL FINDINGS: The frequency of MAP-specific DNA in biopsies by qPCR was significantly higher in CD patients (23.2%, p = 0.03) as compared to controls (7.3%). No significant difference in intestinal MAP presence was observed between ITB patients (12.5%, p = 0.6) and controls (7.3%). MAP presence in blood of CD patients was 10.1% as compared to 4.9% in controls while no patients with ITB were found to be positive (p = 0.1). Using IHC for detection of MAP antigen, the prevalence of MAP in CD was 2.9%, 12.5% in ITB patients and 2.4% in controls. However, long-term follow-up of the patients revealed no significant associations between clinical characteristics and treatment outcomes with MAP positivity. CONCLUSION: We report significantly high prevalence of MAP in intestinal biopsies of CD patients. However, the presence of MAP does not affect the disease course and treatment outcomes in either CD or ITB patients.


Assuntos
Mycobacterium avium subsp. paratuberculosis/genética , Adulto , Antígenos/sangue , Doença de Crohn/complicações , Doença de Crohn/microbiologia , Doença de Crohn/patologia , DNA Bacteriano/química , DNA Bacteriano/metabolismo , Progressão da Doença , Feminino , Hemorroidas/microbiologia , Hemorroidas/patologia , Humanos , Imuno-Histoquímica , Masculino , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Mycobacterium avium subsp. paratuberculosis/metabolismo , Paratuberculose/complicações , Paratuberculose/epidemiologia , Paratuberculose/microbiologia , Fenótipo , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Tuberculose Gastrointestinal/complicações , Tuberculose Gastrointestinal/microbiologia , Tuberculose Gastrointestinal/patologia
10.
Reprod Domest Anim ; 51(2): 227-31, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26841136

RESUMO

This study was designed to examine (i) the seroprevalence of Mycobacterium avium subs paratuberculosis (MAP) in a high-producing dairy herd with clinical symptoms of bovine paratuberculosis, (ii) MAP seroconversion and seronegativation dynamics in the herd and (iii) possible relationships between MAP infection status and herd reproductive performance. One single blood test per cow was performed early post-partum on a monthly basis from day 10-40 post-partum during the first year of the study in 519 cows belonging to a commercial dairy herd. A subset of 111 cows that became pregnant during the study was tested again 60-200 days later during the early foetal period, immediately after the first confirmation of gestation at 58-64 days post-AI. Logistic regression analysis indicated no effect of any independent variable on MAP seropositivity and conception rate 28-34 days post-AI. MAP seropositivity was not a factor affecting the anoestrous, subfertility and early foetal loss rates. In the subset of 111 cows, animals that seroconverted had a 3.9 times greater risk of suffering from early foetal loss (30.3%, 10/33) than the remaining pregnant animals (10.3%, 8/78), (95% confidence interval: 1.11-13.4; p = 0.003). In conclusion, early foetal loss was positively correlated with seroconversion to MAP. Reproductive performance was not impaired by MAP infection.


Assuntos
Aborto Animal/microbiologia , Doenças dos Bovinos/microbiologia , Mycobacterium avium subsp. paratuberculosis/imunologia , Paratuberculose/complicações , Complicações Infecciosas na Gravidez/veterinária , Soroconversão , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/etiologia , Doenças dos Bovinos/imunologia , Feminino , Lactação , Paratuberculose/sangue , Paratuberculose/imunologia , Gravidez , Complicações Infecciosas na Gravidez/sangue
12.
Expert Rev Gastroenterol Hepatol ; 9(12): 1523-34, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26474349

RESUMO

Crohn's disease is a chronic inflammatory bowel disease of unknown cause, affecting approximately 1.4 million North American people. Due to the similarities between Crohn's disease and Johne's disease, a chronic enteritis in ruminant animals caused by Mycobacterium avium paratuberculosis (MAP) infection, MAP has long been considered to be a potential cause of Crohn's disease. MAP is an obligate intracellular pathogen that cannot replicate outside of animal hosts. MAP is widespread in dairy cattle and because of environmental contamination and resistance to pasteurization and chlorination, humans are frequently exposed through contamination of food and water. MAP can be cultured from the peripheral mononuclear cells from 50-100% of patients with Crohn's disease, and less frequently from healthy individuals. Association does not prove causation. We discuss the current data regarding MAP as a potential cause of Crohn's disease and outline what data will be required to firmly prove or disprove the hypothesis.


Assuntos
Doença de Crohn/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/complicações , Animais , Antibacterianos/uso terapêutico , Bovinos , Doença de Crohn/tratamento farmacológico , Doença de Crohn/epidemiologia , Doença de Crohn/genética , Predisposição Genética para Doença , Humanos , Paratuberculose/tratamento farmacológico , Paratuberculose/epidemiologia , Paratuberculose/imunologia
13.
Med Microbiol Immunol ; 204(6): 681-92, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25994082

RESUMO

Mycobacterium avium subsp. paratuberculosis (MAP) and adherent-invasive Escherichia coli (AIEC) have been implicated as primary triggers in Crohn's disease (CD). In this study, we evaluated the prevalence of MAP and E. coli (EC) DNA in peripheral blood from 202 inflammatory bowel disease (IBD) patients at various disease periods and compared against 24 cirrhotic patients with ascites (CIR) (non-IBD controls) and 29 healthy controls (HC). MAP DNA was detected by IS900-specific nested PCR, EC DNA by malB-specific nested PCR and AIEC identity, in selected samples, by sequencing of fimH gene. CD patients with active disease showed the highest MAP DNA prevalence among IBD patients (68 %). Infliximab treatment resulted in decreased MAP detection. CIR patients had high individual and coinfection rates (75 % MAP, 88 % EC and 67 % MAP and EC), whilst HC controls had lower MAP prevalence (38 %) and EC was undetectable in this control group. EC DNA prevalence in IBD patients was highly associated with CD, and 80 % of EC from the selected samples of CD patients analyzed carried the fimH30 allele, with a mutation strongly associated with AIEC. Our results show that coinfection with MAP and AIEC is common and persistent in CD, although the high MAP and EC detection in CIR patients suggested that colonization is, at least, partially dependent on increased gut permeability. Nevertheless, facilitative mechanisms between a susceptible host and these two potential human pathogens may allow their implication in CD pathogenesis.


Assuntos
Bacteriemia , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/epidemiologia , Escherichia coli , Doenças Inflamatórias Intestinais/complicações , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/complicações , Paratuberculose/epidemiologia , Adulto , Idoso , Coinfecção , DNA Bacteriano , Escherichia coli/genética , Feminino , Genes Bacterianos , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium avium subsp. paratuberculosis/genética , Prevalência , Estudos Prospectivos , Adulto Jovem
15.
World J Gastroenterol ; 20(23): 7403-15, 2014 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-24966610

RESUMO

Crohn's disease (CD) is a chronic inflammatory condition that plagues millions all over the world. This debilitating bowel disease can start in early childhood and continue into late adulthood. Signs and symptoms are usually many and multiple tests are often required for the diagnosis and confirmation of this disease. However, little is still understood about the cause(s) of CD. As a result, several theories have been proposed over the years. One theory in particular is that Mycobacterium avium subspecies paratuberculosis (MAP) is intimately linked to the etiology of CD. This fastidious bacterium also known to cause Johne's disease in cattle has infected the intestines of animals for years. It is believed that due to the thick, waxy cell wall of MAP it is able to survive the process of pasteurization as well as chemical processes seen in irrigation purification systems. Subsequently meat, dairy products and water serve as key vehicles in the transmission of MAP infection to humans (from farm to fork) who have a genetic predisposition, thus leading to the development of CD. The challenges faced in culturing this bacterium from CD are many. Examples include its extreme slow growth, lack of cell wall, low abundance, and its mycobactin dependency. In this review article, data from 60 studies showing the detection and isolation of MAP by PCR and culture techniques have been reviewed. Although this review may not be 100% comprehensive of all studies, clearly the majority of the studies overwhelmingly and definitively support the role of MAP in at least 30%-50% of CD patients. It is very possible that lack of detection of MAP from some CD patients may be due to the absence of MAP role in these patients. The latter statement is conditional on utilization of methodology appropriate for detection of human MAP strains. Ultimately, stratification of CD and inflammatory bowel disease patients for the presence or absence of MAP is necessary for appropriate and effective treatment which may lead to a cure.


Assuntos
Doença de Crohn/microbiologia , Mycobacterium avium subsp. paratuberculosis/patogenicidade , Paratuberculose/microbiologia , Animais , Técnicas Bacteriológicas , Doença de Crohn/diagnóstico , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Exposição Ambiental , Microbiologia de Alimentos , Humanos , Leite/microbiologia , Mycobacterium avium subsp. paratuberculosis/genética , Mycobacterium avium subsp. paratuberculosis/crescimento & desenvolvimento , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/complicações , Paratuberculose/diagnóstico , Paratuberculose/transmissão , Medição de Risco , Fatores de Risco , Microbiologia da Água , Abastecimento de Água , Zoonoses
16.
Vet Microbiol ; 171(1-2): 139-46, 2014 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-24794166

RESUMO

This study reports the performance of the single intradermal tuberculin (SIT) test and the interferon-gamma (IFN-γ) assay for Mycobacterium bovis in a cattle herd with high prevalence of paratuberculosis (PTB). A total of 58/350 animals were selected for necropsy based on one or more of the following criteria: positive to SIT, IFN-γ, a breeding cow that seroconverted to PTB and showed signs compatible with a wasting disease. Infection status was determined by post mortem diagnostic tests that included histopathology examination, mycobacterial cultures and PCR identification for M. bovis and Mycobacterium avium subsp. paratuberculosis (MAP). In 7/58 animals primary tuberculosis (TB) lesions, affecting only the retropharyngeal and/or mediastinal lymph nodes, were found; 3/7 animals were found SIT positive. PTB was confirmed in 35/58 animals, of which 30 had seroconverted and 14 had typical clinical signs. 45/58 animals were IFN-γ(+) using the most stringent criterion (cut-off point ≥ 0.05); however, IFN-γ test was only positive in 33 animals when using a higher threshold (cut-off point ≥ 0.1). Three animals co-infected also showed extensive TB and diffuse PTB lesions. These results show that the combined use of SIT and IFN-γ, as interpreted using official guidelines, detected all confirmed cases of TB. Individually, the sensitivity of the SIT was inadequate to diagnose TB-positive animals with an advanced stage of PTB. The large number of IFN-γ(+) animals with no visible TB lesion could be due, in part, to some protection conferred by prior infection with MAP.


Assuntos
Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Mycobacterium bovis/fisiologia , Paratuberculose/complicações , Teste Tuberculínico/veterinária , Tuberculose Bovina/complicações , Tuberculose Bovina/diagnóstico , Animais , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/patologia , Coinfecção , Feminino , Interferon gama/imunologia , Mycobacterium avium subsp. paratuberculosis/fisiologia , Mycobacterium bovis/genética , Mycobacterium bovis/imunologia , Paratuberculose/imunologia , Paratuberculose/patologia , Reação em Cadeia da Polimerase , Proteínas Recombinantes/imunologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espanha , Tuberculina/imunologia , Teste Tuberculínico/normas , Tuberculose Bovina/patologia
18.
Med Microbiol Immunol ; 203(3): 195-205, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24522266

RESUMO

Mycobacterium avium subspecies paratuberculosis (MAP) has been controversially linked with Crohn's disease (CD). Detection of MAP in CD has been highly variable, and one explanation might be the genetic heterogeneity of this syndrome. Many of the single nucleotide polymorphisms (SNPs) linked with CD are contained within genes that are associated with bacterial handling in general, and some are specifically implicated in susceptibility to mycobacterial disease. We tested a cohort of IBD patients (n = 149) to determine whether the presence of MAP was associated with a selection of these SNPs. Blood samples from CD patients (n = 84), ulcerative colitis (UC, n = 65) patients and healthy controls (n = 55) were examined for the presence of MAP and SNPs in ATG16L1, IL12B, NOD2/CARD15, NKx2-3, IL23R and IRGM. Statistical analysis was then used to determine whether there was any association between the presence of MAP and these SNPs. MAP, rs2241880 (ATG16L1) and rs10045431 (IL12B) were found to be significantly associated with CD. The presence of MAP was not related to the status of the SNPs in ATG16L1 or IL12B. We have found no evidence for the contribution of these SNPs to the presence of MAP in CD patients.


Assuntos
Proteínas de Transporte/genética , Doença de Crohn/genética , Subunidade p40 da Interleucina-12/genética , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Proteínas Relacionadas à Autofagia , Doença de Crohn/complicações , Doença de Crohn/microbiologia , Feminino , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Paratuberculose/complicações , Paratuberculose/microbiologia , Adulto Jovem
19.
Cytokine Growth Factor Rev ; 25(1): 57-65, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24529741

RESUMO

Type 1 diabetes (T1D) is due to antigen-specific assaults on the insulin producing pancreatic ß-cells by diabetogenic T-helper (Th)1 cells. (C-X-C motif) ligand (CXCL)10, an interferon-γ inducible Th1 chemokine, and its receptor, (C-X-C motif) receptor (CXCR)3, have an important role in different autoimmune diseases. High circulating CXCL10 levels were detected in new onset T1D patients, in association with a Th1 autoimmune response. Furthermore ß-cells produce CXCL10, under the influence of Th1 cytokines, that suppresses their proliferation. Viral ß-cells infections induce cytokines and CXCL10 expression, inducing insulin-producing cell failure in T1D. CXCL10/CXCR3 system plays a critical role in the autoimmune process and in ß-cells destruction in T1D. Blocking CXCL10 in new onset diabetes seems a possible approach for T1D treatment.


Assuntos
Quimiocina CXCL10/fisiologia , Diabetes Mellitus Tipo 1/etiologia , Receptores CXCR3/fisiologia , Animais , Autoanticorpos/fisiologia , Doenças Autoimunes/imunologia , Quimiocina CXCL10/biossíntese , Quimiocina CXCL10/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/virologia , Infecções por Enterovirus/complicações , Hepatite C/complicações , Humanos , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/fisiologia , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Paratuberculose/complicações
20.
Exp Biol Med (Maywood) ; 239(4): 436-41, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24569700

RESUMO

We wanted to determine if augmented innate immune activation is associated with lesion development in a mycobacterial enhanced intestinal injury model. We evaluated the local immune response in a Mycobacterium avium paratuberculosis + dextran sulfate sodium (Map + DSS) model using BALB/c and severe combined immunodeficient (SCID) mice. Map + DSS BALB/c and SCID mice displayed a similar disease phenotype. Moreover, Map + DSS SCID mice had increased expression of interleukin 1ß (IL-1ß), tumor necrosis factor α (TNF-α), inducible nitric oxide synthase (iNOS) and increased numbers of F4/80 positive cells. Additionally, Map antigen is co-localized with iNOS and IL-1ß positive cells. This suggests that subclinical Map infection promotes innate immune activation following injury to the intestinal epithelium.


Assuntos
Mycobacterium avium subsp. paratuberculosis/imunologia , Paratuberculose/imunologia , Animais , Ceco/microbiologia , Ceco/patologia , Sulfato de Dextrana , Imunidade Inata , Enteropatias/induzido quimicamente , Enteropatias/complicações , Enteropatias/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Paratuberculose/complicações , Paratuberculose/patologia , Redução de Peso
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA