RESUMO
Sequence analysis of HPV16 isolates reveals the presence of genome variants with characteristic mutations. The HPV16 variants have different geographical distribution and diverge into four phylogenetic lineages (A, B, C and D) and 16 sub-lineages: A1, A2, A3 (previously known as European variants), A4 (Asian variant), B1, B2, B3, B4, C1, C2, C3, and C4 (African variants), D1 (North-American variant), D2, D3 (Asian-American variants) and D4. Population studies showed that infections with viruses belonging to specific HPV16 sublineages confer different risks of viral persistence and cancer. In this study, 39 HPV16-positive cervical smears from European women living in Calabria (Italy) were analyzed for the presence of HPV16 variants. Cervical DNA extracts were processed by PCR to amplify L1, the Long Control Region (LCR), E6 and E7, which were sequenced. The sequences were concatenated and the 3169 nucleotides long fragments were characterized by BLAST and phylogenetic analysis. A total of 96 Single Nucleotide Polymorphism (SNPs) were detected, 29 of which mapping in the L1, 45 in the LCR, 15 in the E6 and 7 in the E7. The most common SNP was the T350G (29/39 samples, 74.4%), causing the L83â¯V amino acid change in the E6. Most of the HPV16 isolates (89.7%) had 99% of nucleotide (nt) identity to members of the A1 and A2 sublineages, while 4 isolates had 99% nt identity to members of the B2, B4, C1 and D4 sublineages. In conclusion, viruses belonging to the A1, A2, B2, B4, C1 and D4 HPV16 sublineages were found to circulate in the Calabria region.
Assuntos
Variação Genética , Papillomavirus Humano 16/genética , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/virologia , Vagina/virologia , Esfregaço Vaginal , Adulto , DNA Viral , Feminino , Genótipo , Papillomavirus Humano 16/classificação , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 16/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Mutação , Proteínas Oncogênicas Virais/genética , Infecções por Papillomavirus/imunologia , Polimorfismo de Nucleotídeo Único , Esfregaço Vaginal/métodos , Adulto JovemRESUMO
In recent years, migration has become a significant challenge in Western countries. Migrant populations, coming from hyper-endemic areas, may present parasitic infections that remain latent and asymptomatic even for years, eventually leading to severe complications. Italian guidelines have been established to perform screening guided by the presence of symptoms and/or hypereosinophilia. Parasitological screening was conducted in a migrant population to carry out preventative measures. All migrants were asked to report any symptoms suggesting parasitic infections and list any previous treatment received. Travel data were recorded. Parasitological examination of stools and urine were conducted in all patients regardless of symptoms. In all, 208 consecutive patients were enrolled in our outpatient clinic from November 2016 to August 2017. Thirty-four patients were excluded due to the previous assumption of albendazole or because they did not exhibit suitable samples. Prevalence of parasitic infections was 33/174 (18.9%). A statistically significant difference for the prevalence of parasitic infections was not found between patients who were asymptomatic and without hypereosinophilia compared to those who presented symptoms and/or hypereosinophilia (27/151 [17.9%] vs. 6/23 [26.0%]; p=0.39). By contrast, a statistically significant difference was found for the length of time between arrival in Italy and parasitological examinations (4/51 [7.8%] migrants who arrived in Italy more than six months prior to screening vs. 29/123 [23.6%] migrants who arrived within six months; p= 0.016). Our results did not demonstrate any significant differences in prevalence of parasitic infections between symptomatic or hypereosinophilic and asymptomatic migrants. Thus we feel it inappropriate to support recent guidelines recommending parasitological examinations only in migrants with symptoms and/or hypereosinophilia. By contrast, it would appear important to perform parasitological screening in migrants as soon as possible after their arrival. Since such infestations, if untreated, could result in chronic diseases and complications, and could be transmitted in the host countries, our results have potential implications for public health.
Assuntos
Doenças Parasitárias/diagnóstico , Doenças Parasitárias/epidemiologia , Migrantes , Adolescente , Criança , Feminino , Humanos , Itália/epidemiologia , Masculino , Programas de Rastreamento/normas , Guias de Prática Clínica como Assunto , Prevalência , Estudos Prospectivos , Avaliação de Sintomas , Adulto JovemRESUMO
Preclinical studies suggested that IgG2c isotype may specifically impair skeletal muscle insulin sensitivity in mice. In this study we investigated the association between serum levels of the four IgG subclasses and insulin sensitivity in non-diabetic individuals. Total IgG, IgG1, IgG2, IgG3 and IgG4 levels were measured in 262 subjects. Whole-body insulin sensitivity was assessed by euglycemic hyperinsulinemic clamp. IgG2 levels were positively correlated with BMI, waist circumference, 2-h post-load glucose levels and complement C3. Serum IgG2, but not IgG1, IgG3 and IgG4 levels were negatively correlated with whole-body insulin sensitivity (r = -0.17; P = 0.003) and muscle insulin sensitivity index (r = -0.16; P = 0.03) after adjustment for age and gender. No significant correlation was found between IgG2 levels and hepatic insulin resistance assessed by HOMA-IR and liver IR index. In a multivariable regression analysis including variables known to affect insulin sensitivity such as age, gender, BMI, smoking, lipids, inflammatory markers, fasting and 2-h post-load glucose levels, IgG2 levels were independently associated with insulin-stimulated glucose disposal (ß = -0.115, 95% CI: -0.541 to -0.024; P = 0.03). These data demonstrate the independent association between higher levels of IgG2 and decreased whole-body insulin sensitivity, thus confirming in humans the animal-based evidence indicating the pathogenic role of IgG2 in insulin resistance.
Assuntos
Diabetes Mellitus Tipo 2/sangue , Imunoglobulina G/sangue , Resistência à Insulina/genética , Insulina/metabolismo , Adulto , Glicemia/genética , Estudos Transversais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Jejum , Feminino , Glucose/metabolismo , Técnica Clamp de Glucose , Humanos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Circunferência da CinturaRESUMO
Background/Aims: Correct renal function evaluation is based on estimated glomerular filtration rates (eGFR) and complementary renal damage biomarkers, such as neutrophil gelatinase associated lipocalin (NGAL). The aim of this study was to evaluate eGFR and NGAL modifications and renal impairment during treatment with a direct acting antiviral (DAA) for chronic hepatitis C virus (HCV) infection. METHODS: A retrospective cohort study evaluated eGFR modification during treatment with DAA. Subgroup analysis on serum NGAL was conducted in those receiving sofosbuvir/ledipasvir, with complete follow-up until week 12 after the end of treatment (FU-12). RESULTS: In the 102 enrolled patients, eGFR reduction was observed (from 86.22 mL/min at baseline to 84.43 mL/min at FU-12, P=0.049). Mean NGAL increased in 18 patients (from 121.89 ng/mL at baseline to 204.13 ng/mL at FU-12, P=0.014). At FU-12, 38.8% (7/18) of patients had a plasmatic NGAL value higher than the normal range (36-203 ng/mL) compared with 11.1% (2/18) at baseline (χ 2 =3,704; P=0.054). In contrast, eGFR did not change significantly over the follow-up in this subgroup. Conclusions: In conclusion, compared to a negligible eGFR decline observed in the entire cohort analyzed, a significant NGAL increase was observed after HCV treatment with DAA in a small subgroup. This could reflect tubular damage during DAA treatment rather than glomerular injury.
Assuntos
Rim/fisiopatologia , Lipocalina-2/sangue , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/patologia , Idoso , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Feminino , Genótipo , Taxa de Filtração Glomerular , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Índice de Gravidade de DoençaRESUMO
We aim to investigate some of the pathogenetic mediators of the human echinococcosis and to obtain updated epidemiological findings on cases of echinococcosis in Calabria, Southern Italy. Echinococcosis diagnosis was based on imaging, serological investigations, and molecular assay. Indeed, real-time PCR indicated the presence of G2/G3 genotypes of Echinococcus granulosus complex. Regarding pathogenesis, a relevant novel tool of immune depression should be deemed the reduced level of serum MCP-1. Also, we found a previously unreported VEGF, possibly associated with neovascularization requested by the parasite cyst metabolism. Cytokine profiles suggest a bias of the immunity toward Th2 and Treg responses. Nitric oxide levels exhibited a significant decrease one week after therapy versus basal level measured before surgery and/or chemotherapy. An increase of serum total IgE class and IgG4 subclass was found in Echinococcus-positive patients versus controls. Our data demonstrated an endemic spreading, at least in the province of Catanzaro and neighboring Calabria territories, for such parasitosis with the novel issue of the number of female overcoming male cases. In conclusion, the novel findings of this study were the increased VEGF and the reduced serum MCP-1 in the studied cases, as well as the number of Echinococcus-infected females overcoming the infected males.
Assuntos
Quimiocina CCL2/metabolismo , Equinococose/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Equinococose/imunologia , Echinococcus granulosus/imunologia , Echinococcus granulosus/patogenicidade , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th2/imunologia , Células Th2/metabolismoRESUMO
BACKGROUND: Although analysis of the Human papillomavirus (HPV) genotype spread in a particular area has a crucial impact on public health and prevention programmes, there is a lack of epidemiological data regarding HPV in the Calabria region of Italy. We therefore update information on HPV age/genotype distribution by retrospectively analysing a cohort of women, with and without cervical lesions, living in Calabria, who underwent HPV DNA testing; moreover, we also evaluated HPV age/genotype distribution in a subset of patients with cervical lesions. METHODS: Cervical scrape specimens obtained from 9590 women (age range 20-75 years) from January 2010 to December 2015 were tested for HPV DNA. Viral types were genotyped by Linear Array HPV Genotyping® test (Roche, USA) at the Clinical Microbiology Operative Unit of six hospitals located in four provinces of the Calabria region. Cervical scrape specimens were also used to perform Pap smears for cytological analysis in a subset of 405 women; cytological classification of the samples was performed according to the Bethesda classification system. RESULTS: A total of 2974 women (31%) (C.I. 95% 30.09-31.94) were found to be HPV DNA positive for at least one (57.3%) or several (42.7%) HPV genotypes. Of single genotype HPV infections, 46.5% and 36.4 % were classed as high-risk (HR, Group 1) and low-risk (LR, Group 3) respectively, while 16.9% were classed as probably/possibly carcinogenic and 0.2% undetermined risk. Stratified by age, total HPV distribution, showed the highest prevalence within the range 30-39 years (37.2%), while single genotype infection distribution displayed a peak in women from the age range 20-29 years (37.5%). The most common high-risk HPV type was HPV 16 (19.1%), followed by HPV 31 (9.1%). CONCLUSIONS: We provide epidemiological data on HPV age/genotype distribution in women living in the Calabria region with or without cytological abnormalities, further to the enhancement of HPV screening/prevention programmes for the local population.
RESUMO
Pregnant women with urinary schistosomiasis should be treated, but screening is not implemented in migrants. We report herein a case of a migrant diagnosed late into pregnancy, after diagnosis was made in her husband. Praziquantel was safe and effective. Schistosomiasis should be considered in pregnant women from endemic countries.
Assuntos
Complicações Parasitárias na Gravidez , Schistosoma haematobium/isolamento & purificação , Esquistossomose Urinária/parasitologia , Migrantes , Adulto , Animais , Anti-Helmínticos/administração & dosagem , Feminino , Humanos , Masculino , Praziquantel/administração & dosagem , Gravidez , Complicações Parasitárias na Gravidez/tratamento farmacológico , Esquistossomose Urinária/tratamento farmacológico , Adulto JovemRESUMO
Due to shared transmission routes, coinfection with Hepatitis C Virus (HCV) is common in patients infected by Human Immunodeficiency Virus (HIV). The immune-pathogenesis of liver disease in HIV/HCV coinfected patients is a multifactorial process. Several studies demonstrated that HIV worsens the course of HCV infection, increasing the risk of cirrhosis and hepatocellular carcinoma. Also, HCV might increase immunological defects due to HIV and risk of comorbidities. A specific cross-talk among HIV and HCV proteins in coinfected patients modulates the natural history, the immune responses, and the life cycle of both viruses. These effects are mediated by immune mechanisms and by a cross-talk between the two viruses which could interfere with host defense mechanisms. In this review, we focus on some virological/immunological mechanisms of the pathogenetic interactions between HIV and HCV in the human host.
Assuntos
Coinfecção/virologia , Infecções por HIV/complicações , Infecções por HIV/virologia , Hepatite C/complicações , Hepatite C/virologia , Animais , Antivirais/uso terapêutico , HIV , Hepacivirus , Humanos , Sistema Imunitário , Inflamação/patologia , Inflamação/virologia , Cirrose Hepática/patologia , Cirrose Hepática/virologiaRESUMO
Nasopharyngeal carcinoma (NPC) is a rare neoplasm which is associated with Epstein-Barr virus (EBV). First of all, we reviewed the literature on NPC treatment. Radio/chemotherapy is currently the gold standard but unfortunately is affected by rates of failure ranging from 7% up to 58%. Because NPC development is promoted by the EBV latent life cycle, EBV-targeted treatments were investigated. Firstly, forcing cytolytic virus activation through administration of gemcitabine and/or valproic acid before administration of a nucleoside analogue showed anti-tumoral activity in vitro as well as in murine model and it was also well tolerated in humans. Secondly, the association of autologous EBV-specific cytotoxic T lymphocytes with chemotherapy correlated with an improved median survival and was safe but not effective versus metastatic lesions. Thirdly, suppression of late membrane protein-1 in the clinic proved controversial because it gave resistance to chemotherapy and, on the other hand, increased radiosensitivity. Finally, we suggest future perspectives for clinical research which should include both prospective and observational cohort studies to assess the role of different risk factors in the development of NPC and the effectiveness of new investigational treatments.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Nasofaríngeas/terapia , Animais , Carcinoma , Quimiorradioterapia/métodos , Quimioterapia Adjuvante/métodos , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Medicina Baseada em Evidências , Humanos , Imunoterapia Adotiva/métodos , Ativação Linfocitária , Carcinoma Nasofaríngeo , Resultado do Tratamento , Ácido Valproico/administração & dosagem , GencitabinaRESUMO
We present clinical cases, which underline some difficulties in diagnosis and treatment of hepatitis C virus (HCV) infection. Case report #1 shows a patient who avoided clinical follow-up for HCV until the development of hepatocellular carcinoma. In this patient, non-invasive procedures did not allow to make a differential diagnosis between hydatidosis and hepatocellular carcinoma but diagnosis was only made with liver biopsy.
Assuntos
Carcinoma Hepatocelular/virologia , Hepacivirus/fisiologia , Hepatite C/virologia , Neoplasias Hepáticas/virologia , Idoso , Biópsia , Carcinoma Hepatocelular/diagnóstico , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C/diagnóstico , Humanos , Neoplasias Hepáticas/diagnóstico , MasculinoRESUMO
Circulation of HCV genotype 2 has been described in European Countries where numerous subtypes and unclassified HCV 2 lineages have been reported. In Italy, subtype 1b is the most prevalent, followed by genotype 2. In the present study, phylogeny of HCV 2c was investigated. The phylogeny of HCV 2c isolated from 54 Italian patients in the Calabria region (Southern Italy) was investigated by analyzing a fragment of the NS5B gene. Patients came from 5 metropolitan areas and a small village (Sersale). These areas were geographically dispersed throughout the entire region. A Bayesian coalescent-based framework was used to estimate origin and spreading of HCV 2c in this region. Phylogenetic analysis showed that 28 Italian sequences were intermixed with foreign HCV 2c reference sequences and grouped into 3 major clades: A, B, and C. Nineteen inter-clade sequences were associated uniquely with surgery as risk factor for HCV acquisition. By contrast, a sub-cluster within clade B was associated with blood transfusion. Moreover, sequences from Sersale village grouped in the Italian sub-cluster and were intermixed with 10 sequences from metropolitan areas. The three isolates with the longest branch came from Sersale and belonged to patients who had glass syringes as risk factor. HCV 2c isolates from the Calabria region shared a common ancestor whose origin was traced back to 1889. Our results suggest that, after its introduction - possibly as a result of population movements between Italy and African Countries during Italian colonialism - HCV 2c spread through multiple risk factors, not including intravenous drug use. So, transmission chains followed a pathway different from other European Countries. Although HCV incidence is decreasing, these ways are still ongoing, possibly justifying stability in the relative prevalence of HCV 2c.
Assuntos
Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C/epidemiologia , Filogenia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biologia Computacional , Bases de Dados Genéticas , Conjuntos de Dados como Assunto , Evolução Molecular , Feminino , Hepatite C/história , História do Século XX , História do Século XXI , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA , Proteínas não Estruturais Virais/genéticaRESUMO
Systemic Bartonella henselae infections are unusual in immunocompetent adults. However, here we report one such case of bartonellosis in a 34-year-old patient, who presented with fever and multinodular splenomegaly. We also describe a novel method of identifying Bartonella henselae by real-time quantitative polymerase chain reaction and sequencing of amplified products. This could prevent splenic bartonellosis being mistaken for lymphoma and thereby avert unnecessary splenectomy.
Assuntos
Infecções por Bartonella/microbiologia , Bartonella henselae/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Esplenopatias/microbiologia , Adulto , Antibacterianos/uso terapêutico , DNA Bacteriano , Feminino , Humanos , ImunocompetênciaRESUMO
BACKGROUND: Procalcitonin (PCT) is a polypeptide with several cationic aminoacids in its chemical structure and it is a well known marker of sepsis. It is now emerging that PCT might exhibit some anti-inflammatory effects. The present study, based on the evaluation of the in vitro interaction between PCT and bacterial lipopolisaccharide (LPS), reports new data supporting the interesting and potentially useful anti-inflammatory activity of PCT. RESULTS: PCT significantly decreased (p < 0.05) the limulus amoebocyte lysate (LAL) assay reactivity of LPS from both Salmonella typhimurium (rough chemotype) and Escherichia coli (smooth chemotype). Subsequently, the in vitro effects of PCT on LPS-induced cytokine release were studied in human peripheral blood mononuclear cells (PBMC). When LPS was pre-incubated for 30 minutes with different concentrations of PCT, the release of interleukin-10 (IL-10) and tumor necrosis factor alpha (TNFα) by PBMC decreased in a concentration-dependent manner after 24 hours for IL-10 and 4 hours for TNFα. The release of monocyte chemotactic protein-1 (MCP-1) exhibited a drastic reduction at 4 hours for all the PCT concentrations assessed, whereas such decrease was concentration-dependent after 24 hours. CONCLUSIONS: This study provides the first evidence of the capability of PCT to directly neutralize bacterial LPS, thus leading to a reduction of its major inflammatory mediators.
Assuntos
Calcitonina/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/imunologia , Precursores de Proteínas/metabolismo , Peptídeo Relacionado com Gene de Calcitonina , Células Cultivadas , Escherichia coli/química , Escherichia coli/imunologia , Humanos , Teste do Limulus , Salmonella typhimurium/química , Salmonella typhimurium/imunologiaRESUMO
Crucial steps in high-risk human papillomavirus (HR-HPV)-related carcinogenesis are the integration of HR-HPV into the host genome and loss of viral episomes. The mechanisms that promote cervical neoplastic progression are, however, not clearly understood. During HR-HPV infection, the HPV E5 protein is expressed in precancerous stages but not after viral integration. Given that it has been reported that loss of HPV16 episomes and cervical tumor progression are associated with increased expression of antiviral genes that are inducible by type I interferon (IFN), we asked whether E5, expressed in early phases of cervical carcinogenesis, affects IFN-ß signaling. We show that the HPV type 16 (HPV16) E5 protein expression per se stimulates IFN-ß expression. This stimulation is specifically mediated by the induction of interferon regulatory factor 1 (IRF-1) which, in turn, induces transcriptional activation of IRF-1-targeted interferon-stimulated genes (ISGs) as double-stranded RNA-dependent protein kinase R (PKR) and caspase 8. Our data show a new and unexpected role for HR-HPV E5 protein and indicate that HPV16 E5 may contribute to the mechanisms responsible for cervical carcinogenesis in part via stimulation of IFN-ß and an IFN signature, with IRF-1 playing a pivotal role. HPV16 E5 and IRF-1 may thus serve as potential therapeutic targets in HPV-associated premalignant lesions.
Assuntos
Interações Hospedeiro-Patógeno , Papillomavirus Humano 16/imunologia , Fator Regulador 1 de Interferon/metabolismo , Interferon beta/biossíntese , Queratinócitos/imunologia , Proteínas Oncogênicas Virais/metabolismo , Linhagem Celular , Papillomavirus Humano 16/patogenicidade , Humanos , Queratinócitos/virologiaRESUMO
Veillonella parvula is an anaerobic gram-negative coccus that is part of the normal flora of the animal and human mouth and gastrointestinal and genitourinary tracts. Oral V. parvula is involved in the development of early periodontal disease as well as different types of serious infections. Present data on molecular mechanisms responsible for innate immune response against Veillonella are very scanty. The aim of this study was to investigate the Toll-like receptor (TLR) pathways responsible for V. parvula lipopolysaccharide (LPS) and to identify the intracellular pathways induced by this recognition. V. parvula LPS stimulated tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) release in human peripheral blood mononuclear cells (PBMC) in a dose-dependent manner. Pretreatment of cells with a TLR4 antagonist significantly reduced TNF-alpha and IL-6 production in PBMC stimulated with either Veillonella or Escherichia coli LPS. However, V. parvula LPS was 10- to 100-fold less active than E. coli LPS for cytokine induction. TNF-alpha, IL-1beta, IL-6, and IL-10 were released in wild-type and TLR2(-/-), but not TLR4(-/-), mouse macrophage cultures. V. parvula LPS was able to activate the human PBMC p38 mitogen-activated protein kinase (MAPK). A specific p38 MAPK inhibitor strongly inhibited V. parvula LPS-induced TNF-alpha, IL-1beta, IL-6, and IL-10. In conclusion, V. parvula LPS is able to induce cytokine production in both human and murine in vitro models, although it is less effective than Enterobacteriaceae LPS. V. parvula LPS-stimulated cytokine induction, as well as p38 MAPK activation, are TLR4-dependent features.
Assuntos
Leucócitos Mononucleares/imunologia , Macrófagos Peritoneais/imunologia , Receptor 2 Toll-Like/imunologia , Receptor 4 Toll-Like/imunologia , Veillonella/imunologia , Animais , Bartonella quintana/imunologia , Escherichia coli/imunologia , Humanos , Interleucina-10/agonistas , Interleucina-10/imunologia , Interleucina-10/metabolismo , Interleucina-1beta/agonistas , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Interleucina-6/agonistas , Interleucina-6/imunologia , Interleucina-6/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Knockout , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/agonistas , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
Ascaris presence in humans has been associated with high levels of blood eosinophils and serum IgE. This study was designed to address the influence of Ascaris infection on allergic and inflammatory parameters of atopic subjects. A cross-sectional design was used, and atopic individuals to be assessed were divided into 3 groups including Ascaris-infected, anti-Ascaris IgG-positive (seropositive), and control subjects. All subjects enrolled had positive skin test reactivity to at least 1 perennial or seasonal allergen; however, levels of C-reactive protein, C3, and C4 were within normal range values. Eosinophil percentage was not significantly different among the groups studied. Total IgE and specific anti-Ascaris IgE levels in the seropositive group were significantly higher than concentrations found in both control and infected groups. Interleukin (IL)-4 release in Ascaris-infected patients was significantly increased versus seropositives, who were able to produce more IL-4 than controls. The levels of IL-10 were lower in the seropositives as well as infected subjects in comparison with controls. CD25(+) lymphocyte populations were significantly increased in the infected group versus the seropositives as well as the controls. Lung function tests of some selected seropositive subjects were significantly impaired. The same parameters of a representative infected patient were not different from controls. Our data on T helper type 2 cells (Th2) and regulatory T cells (Treg) features, as well as CD25(+) lymphocyte increase, suggest an Ascaris-induced mechanism leading to parasite survival. Moreover, the stable control of both T helper type 1 cells (Th1) and Th2 immunity cascades, paralleled by the absence of overwhelming inflammatory systemic reactions and lack of allergic syndromes, may result in a favorable host condition.
Assuntos
Ascaríase/imunologia , Ascaris lumbricoides/imunologia , Hipersensibilidade Imediata/imunologia , Imunoglobulina E/sangue , Subunidade alfa de Receptor de Interleucina-2/análise , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Idoso , Análise de Variância , Animais , Anticorpos Antiprotozoários/sangue , Estudos Transversais , Eosinófilos/imunologia , Fezes/parasitologia , Feminino , Humanos , Imunoglobulina E/metabolismo , Interferon gama/sangue , Interleucinas/sangue , Pessoa de Meia-Idade , Testes de Função Respiratória , Testes Cutâneos , Fator de Crescimento Transformador beta/sangue , Fator de Necrose Tumoral alfa/sangueRESUMO
Bartonella quintana (B. quintana) is a facultative, intracellular bacterium, which causes trench fever, chronic bacteraemia and bacillary angiomatosis. Little is known about the recognition of B. quintana by the innate immune system. In this review, we address the impact of Toll-like receptors (TLRs) on the recognition of B. quintana and the activation of the host defense. When experimental models using human mononuclear cells, transfected CHO cells, or TLR2-/- and TLR4-/- mice were used, differential effects of TLR2 and TLR4 have been observed. B. quintana micro-organisms stimulated cytokine production through TLR2-mediated signals, whereas no role for TLR4 in the recognition of this pathogen was observed. When single, water-phenol extraction was performed, B. quintana LPS, stimulated cytokine production in a TLR2-dependent manner. However, when double extraction was performed in order to generate highly purified LPS, B. quintana LPS entirely lost its capacity to stimulate cytokines, demonstrating that non-LPS components of B. quintana are responsible for the recognition through TLR2. Moreover, B. quintana LPS was shown to be a potent antagonist of Toll-like receptor 4 (TLR4). In conclusion, B. quintana is an inducer of cytokines through TLR2-, but not TLR4-, dependent mechanisms. This stimulation is induced by bacterial components other than lipopolysaccharide. B. quintana LPS is a naturally occurring antagonist of Toll-like receptor 4 (TLR4). In view of the role played by TLR4 in inflammation, B. quintana LPS may be useful as an anti-TLR4 agent with therapeutic potential in both infections and autoimmune inflammation.
Assuntos
Bartonella quintana/imunologia , Receptores Toll-Like/imunologia , Febre das Trincheiras/imunologia , Animais , Bartonella quintana/fisiologia , Citocinas/imunologia , Citocinas/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Lipopolissacarídeos/imunologia , Receptor 2 Toll-Like/imunologia , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/imunologia , Receptor 4 Toll-Like/metabolismo , Receptores Toll-Like/metabolismo , Febre das Trincheiras/metabolismo , Febre das Trincheiras/microbiologiaRESUMO
Bartonella quintana is a gram-negative microorganism that causes trench fever and chronic bacteremia. B. quintana lipopolysaccharide (LPS) was unable to induce the production of proinflammatory cytokines in human monocytes. Interestingly, B. quintana LPS is a potent antagonist of Toll-like receptor 4 (TLR4), as it inhibited both mRNA transcription and the release of tumor necrosis factor alpha, interleukin 1beta (IL-1beta), and IL-6 by Escherichia coli LPS in human monocytes, at ratios ranging from 1,000:1 to 10:1 (B. quintana LPS to E. coli LPS). Likewise, B. quintana LPS blocked the interaction of E. coli LPS with TLR4 in transfected cell lines. The extent of the inhibitory effect of B. quintana LPS was demonstrated in microarray studies, which showed downregulation of practically all genes induced by LPS in monocytes. Because of the role of TLR4 in inflammation, B. quintana LPS may prove useful as a potent anti-TLR4 agent with therapeutic potential in both infections and autoimmune inflammation.
Assuntos
Bartonella quintana/química , Bartonella quintana/imunologia , Lipopolissacarídeos/imunologia , Receptor 4 Toll-Like/antagonistas & inibidores , Células Cultivadas , Regulação para Baixo , Regulação Bacteriana da Expressão Gênica , Humanos , Interleucina-1beta/antagonistas & inibidores , Interleucina-6/antagonistas & inibidores , Monócitos/imunologia , Análise de Sequência com Séries de Oligonucleotídeos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/genéticaRESUMO
AIM: To evaluate the prevalence of Giardia lamblia (G. lamblia) infection in patients with irritable bowel syndrome (IBS) and dyspepsia and to establish which is the most accurate test to diagnose the infection in this setting. METHODS: One hundred and thirty-seven patients who consecutively attended the Outpatient Gastroenterology Clinic for the first time between January 2002 and December 2003 due to symptoms of IBS and/or dyspepsia were recruited. All patients underwent clinical evaluation, first-step haematology and chemistry tests, serologic assays for celiac disease, lactose-H(2) breath test, abdominal ultrasonography, and esophagogastroduodenoscopy. Helicobacter pylori status was evaluated. In patients with symptoms of IBS older than 45 years, colonoscopy was also performed. In all patients, duodenal biopsies and stool samples were examined for trophozoites and cysts of G. lamblia by several methods. RESULTS: G. lamblia was identified in 9 patients. The following diagnoses were also made: IBS (100/137, 73%), functional dyspepsia (62/137, 45%), organic dyspepsia (33/137, 24%), and lactose intolerance (75/137, 55%). A significant association was found between giardiasis and H pylori infection (c2=6.632, OR=12.4, CI=1.5-68.1). There were no symptoms that reliably allowed the recognition of giardiasis. Direct search of the parasite in duodenal biopsy and stool sample examinations gave concordant results in all cases while histological examination of duodenal biopsies displayed a low sensitivity (e.g., 22.2%). CONCLUSION: In this consecutive series, diagnosis of G. lamblia infection accounted for 6.5% of patients with IBS and dyspepsia. Duodenal biopsies for diagnosis of giardiasis may be unnecessary if stool sample examination is performed.
Assuntos
Dispepsia/complicações , Dispepsia/parasitologia , Giardia lamblia , Giardíase/complicações , Giardíase/diagnóstico , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/parasitologia , Adulto , Idoso , Animais , Biópsia , Duodeno/microbiologia , Duodeno/parasitologia , Duodeno/patologia , Fezes/parasitologia , Feminino , Infecções por Helicobacter/complicações , Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos ProspectivosRESUMO
Previous studies demonstrated that live Bartonella quintana often induces angioproliferative lesions in humans. It modulates endothelial cell apoptotic and inflammatory patterns, thus inducing a very early overexpression of caspase 8 and Apaf-1 and increasing mRNA production of TNF-alpha, interleukin-8, and E-selectin. However, starting at 10 hours postinfection, the bacteria provoke antiapoptotic effects that induce an increase of bcl-2 gene transcription. To gain further insight into the cellular mechanisms that regulate apoptosis, survival and proliferation, we studied the modulation of mitogen-activated protein kinase (MAPK) and the activation state of cdc2 kinase, which regulates progression into mitosis. Confocal microscopy findings indicated a maximum rate of Bartonella entry into host cells between postinfection hours 6 and 10. Live bacteria caused substantially higher apoptosis of human umbilical vein endothelial cells-cryopreserved (HUVEC-C) than heat- and trypsin-inactivated microorganisms. During the first 6 hours postinfection, B. quintana triggered a peak of apoptosis, induced activation of p38 MAPK and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), with bacterial clusters appearing at the cellular surface of the HUVEC-C. However, at 8 to 24 hours postinfection, B. quintana was internalized and inhibited proapoptotic signals such as p38 MAPK and SAPK/JNK while inducing antiapoptotic signals. Indeed, expression of the bcl-2 gene and the increase of the bcl-2 kinase active form was concomitant to activation of mitosis, as shown by cdc2 protein activation. These data thus suggest that mechanisms that induce mitotic activity and inhibit apoptotic signals may contribute to the ability of B. quintana to cause vascular proliferation.