RESUMO
Loss-of-function (LOF) mutations in NFKB1, coding for p105, may cause common variable immunodeficiency due to dysregulation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κΒ) pathway. Monoallelic LOF variants of NFKB1 can predispose to uncontrolled inflammation including sterile necrotizing fasciitis or pyoderma gangrenosum. In this study, we explored the impact of a heterozygous NFKB1 c.C936T/p.R157X LOF variant on immunity in sterile fasciitis patients and their family members. The p50 or p105 protein levels were reduced in all variant carriers. Interleukin-1ß (IL-1ß) and interleukin-8 (IL-8) levels were elevated in vitro, potentially contributing to the very high neutrophil counts observed during fasciitis episodes. Phosphorylation of p65/RelA was reduced in p.R157X neutrophils suggesting defective activation of canonical NF-κB. Oxidative burst after NF-κB-independent phorbol 12-myristate 13-acetate (PMA) stimulation was similar in both p.R157X and control neutrophils. Comparable amounts of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex subunits were found in p.R157X and control neutrophils. However, a compromised oxidative burst was observed in p.R157X neutrophils following activation of NF-κB-dependent mechanisms following stimulation of toll-like receptor 2 (TLR2) and Dectin-1. Neutrophil extracellular trap formation was not affected by p.R157X. In summary, the NFKB1 c.C936T/p.R157X LOF variant has an impact on inflammation and neutrophil function and may play a role in the pathogenesis of sterile necrotizing fasciitis.
Assuntos
Fasciite Necrosante , NF-kappa B , Humanos , NF-kappa B/metabolismo , Neutrófilos/metabolismo , Fasciite Necrosante/genética , Explosão Respiratória , Inflamação/genética , Inflamação/metabolismo , Subunidade p50 de NF-kappa B/genéticaRESUMO
OBJECTIVE: Oxidized epitopes such as malondialdehyde-acetaldehyde (MAA) play a crucial role in the progression of atherosclerosis through activation of the humoral immune response. The exact mechanism of the association between atherosclerosis and periodontal diseases is not fully understood. The aim of the current study is to evaluate the association of oral humoral immune response to oxidized epitopes with parameters of periodontal disease. MATERIALS AND METHODS: The Parogene cohort consist of patients who have undergone coronary angiography due to cardiac symptoms. In this study, 423 patients were randomly selected for an extensive oral examination. Salivary Immunoglobulin A to oxidized epitopes and bacterial antigens was determined by chemiluminescence immunoassay. RESULTS: In a binary logistic regression model adjusted with periodontal disease confounders, periodontal pocket depth (PPD) 4-5 mm associated with salivary IgA antibodies to MAA-LDL (p = 0.034), heat shock protein 60 of Aggregatibacter actinomycetemcomitans (p = 0.045), Porphyromonas gingivalis (p = 0.045), A. actinomycetemcomitans (p = 0.005), P. intermedia (p = 0.020), and total IgA (p = 0.003). CONCLUSIONS: The current study shows the association of salivary IgA to MAA-LDL with PPD 4-5 mm in a cohort of patients with chronic coronary artery disease. Humoral immune cross-reactivation to oxidized epitopes such MAA-LDL could partly explain the link of periodontitis with systemic diseases.
Assuntos
Aterosclerose , Doenças Periodontais , Acetaldeído/metabolismo , Aggregatibacter actinomycetemcomitans , Antígenos de Bactérias/metabolismo , Chaperonina 60/metabolismo , Epitopos/metabolismo , Humanos , Imunoglobulina A/metabolismo , Imunoglobulina A Secretora/metabolismo , Malondialdeído/metabolismo , Bolsa Periodontal , Porphyromonas gingivalis/metabolismoRESUMO
Malondialdehyde acetaldehyde (MAA) adducts are generated under oxidative stress and shown to be highly immunogenic. Our aim was to investigate the recognition of MAA adducts by human natural antibodies in newborns before or at the time of full-term pregnancy. Plasma samples of pre-term (n = 11) and full-term (n = 36) newborns were enriched in specific IgM binding to MAA adducts compared with the maternal plasma IgM levels. Umbilical cord blood lymphocyte phage display library was generated to clone Fabs that specifically recognized MAA adducts without cross-reactivity to malondialdehyde. Fab clones from the antibody libraries of the pre-term and full-term newborns showed high sequence homology to the germline genes encoding the variable regions of antibodies, confirming that these Fabs represented the natural antibody repertoire of human fetuses. The MAA-specific umbilical cord blood Fabs bound to apoptotic human endothelial cells and the binding was efficiently competed with MAA adducts. The MAA-specific Fabs also recognized epitopes on advanced atherosclerotic lesions, and the uptake of infrared (IR)-labeled MAA-low-density lipoprotein by mouse J774A.1 macrophages was significantly reduced in the presence of these Fabs. In conclusion, MAA adducts were identified as one of the major antigenic targets for human natural antibodies already before the time of birth. MAA-specific natural antibodies are suggested to regulate apoptotic cell clearance starting from fetal development and to participate in the immunomodulation of atherosclerosis development during adulthood.
Assuntos
Acetaldeído/imunologia , Imunoglobulina M/imunologia , Malondialdeído/imunologia , Estresse Oxidativo/imunologia , Placa Aterosclerótica/imunologia , Polímeros/metabolismo , Apoptose/imunologia , Feminino , Sangue Fetal/imunologia , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Imunoglobulina M/genética , Recém-Nascido , Masculino , Biblioteca de Peptídeos , Fagocitose , Gravidez , Engenharia de Proteínas , SuéciaRESUMO
We aimed to study levels of natural antibodies in plasma, and their associations to clinical and fecal biomarkers, before and 6 months after Roux-en-Y gastric bypass (RYGB) surgery. Thirty individuals with obesity [16 type 2 diabetic, 14 non-diabetic (ND)] had RYGB surgery. Total plasma IgA, IgG and IgM antibody levels and specific antibodies to oxidized low-density lipoprotein (oxLDL), malondialdehyde-acetaldehyde adducts, Porphyromonas gingivalis gingipain A hemagglutinin domain (Rgp44), and phosphocholine were measured using chemiluminescence immunoassay. Associations between plasma and fecal antibodies as well as clinical markers were analyzed. RYGB surgery reduced blood pressure, and the glycemic state was improved. A higher level of diastolic blood pressure was associated with lower plasma antibodies to oxLDL after surgery. Also, lower level of glucose markers associated with lower level of plasma antibodies to bacterial virulence factors. Antibodies to oxLDL decreased after surgery, and positive association between active serum lipopolysaccharide and specific oxLDL antibodies was detected. Total IgG levels decreased after surgery, but only in ND individuals. Reduced level of total plasma IgG, improved state of hypertension and hyperglycemia and their associations with decreased levels of specific antibodies in plasma, suggest an improved state of systemic inflammation after RYGB surgery.
Assuntos
Diabetes Mellitus Tipo 2 , Derivação Gástrica , Humanos , Glicemia , Pressão Sanguínea , Glucose , Imunoglobulina M , Imunoglobulina GRESUMO
Phosphatidylethanol (PEth) is a group of alcohol-modified phospholipids present in cell membranes after heavy drinking. Our aim was to demonstrate the presence of human plasma antibodies binding to PEth and to address their specificity and value in detecting subjects engaged in heavy alcohol consumption. Antibodies to PEth were analyzed in plasma from heavy drinkers (n=20), patients with alcoholic pancreatitis (n=58) and control subjects (n=24), using chemiluminescent immunoassay. Heavy drinkers and patients with alcoholic pancreatitis demonstrated significantly lower levels of plasma IgG, IgA and IgM titers to PEth compared with controls (P<0.001). The specificity of the antibodies to PEth was demonstrated with competitive liquid phase immunoassays and flow cytometry. The plasma IgG, but not IgA or IgM, titers to PEth in heavy drinkers correlated with the whole blood PEth concentration determined by liquid chromatography-mass spectrometry (r=0.655, P=0.002). Compared with traditional markers for alcohol abuse (aspartate aminotransferase, gamma-glutamyl transpeptidase and mean corpuscular volume), receiver operating characteristic curve analysis showed that a low plasma IgA to PEth had the highest area under the curve (AUC 0.940, P<0.001). In conclusion, plasma IgG, IgA and IgM antibodies binding specifically to PEth were found in subjects of all study groups. Subjects with heavy alcohol consumption showed markedly lower plasma immunoglobulin levels to PEth, potentially making them useful as a biomarker to distinguish heavy from moderate alcohol use.
Assuntos
Consumo de Bebidas Alcoólicas , Alcoolismo , Anticorpos/sangue , Glicerofosfolipídeos/imunologia , Pancreatite Alcoólica , Adulto , Consumo de Bebidas Alcoólicas/sangue , Consumo de Bebidas Alcoólicas/imunologia , Alcoolismo/diagnóstico , Alcoolismo/imunologia , Biomarcadores/sangue , Estudos de Casos e Controles , Cromatografia Líquida , Feminino , Humanos , Imunoensaio , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Pancreatite Alcoólica/diagnóstico , Pancreatite Alcoólica/imunologia , Curva ROC , Sensibilidade e EspecificidadeRESUMO
Krüppel-like factor 2 (KLF2) is a transcription factor with significant roles in development, maturation, differentiation, and proliferation of several cell types. In immune cells, KLF2 regulates maturation and trafficking of lymphocytes and monocytes. KLF2 participates in regulation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway. Although pulmonary arterial hypertension (PAH) related to KLF2 genetic variant has been suggested, genetic role of KLF2 associated with immune dysregulation has not been described. We identified a family whose members suffered from lymphopenia, autoimmunity, and malignancy. Whole exome sequencing revealed a KLF2 p.(Glu318Argfs*87) mutation disrupting the highly conserved zinc finger domain. We show a reduced amount of KLF2 protein, defective nuclear localization and altered protein-protein interactome. The phenotypically variable positive cases presented with B and T cell lymphopenia and abnormalities in B and T cell maturation including low naive T cell counts and low CD27+IgD-IgM- switched memory B cells. KLF2 target gene (CD62L) expression was affected. Although the percentage of (CD25+FOXP3+, CD25+CD127-) regulatory T cells (Treg) was high, the naive Treg cells (CD45RA+) were absent. Serum IgG1 levels were low and findings in one case were consistent with common variable immunodeficiency (CVID). Transcription of NF-κß pathway genes and p65/RelA phosphorylation were not significantly affected. Inflammasome activity, transcription of genes related with JAK/STAT pathway and interferon signature were also comparable to controls. Evidence of PAH was not found. In conclusion, KLF2 variant may be associated with familial immune dysregulation. Although the KLF2 deficient family members in our study suffered from lymphopenia, autoimmunity or malignancy, additional study cohorts are required to confirm our observations.
Assuntos
Linfopenia , Nascimento Prematuro , Feminino , Humanos , Janus Quinases , Fatores de Transcrição STAT , Transdução de Sinais , Dedos de Zinco , Fatores de Transcrição Kruppel-Like/genética , ZincoRESUMO
Obesity is associated with low-grade inflammation and increased systemic oxidative stress. Roux-en-Y gastric bypass (RYGB) surgery is known to ameliorate the obesity-induced metabolic dysfunctions. We aimed to study the levels of natural antibodies in feces, before and 6 months after RYGB surgery in obese individuals with and without type 2 diabetes (T2D). Sixteen individuals with T2D and 14 non-diabetic (ND) individuals were operated. Total IgA, IgG and IgM antibody levels and specific antibodies to oxidized low-density lipoprotein (oxLDL), malondialdehyde-acetaldehyde adducts (MAA adducts), Porphyromonas gingivalis gingipain A hemagglutinin domain (Rgp44) and phosphocholine (PCho) were measured using chemiluminescence immunoassay. Total fecal IgA was elevated, while total IgM and IgG were not affected by the surgery. Fecal natural IgM specific to oxLDL decreased significantly in both T2D and ND individuals, while fecal IgM to Rgp44 and PCho decreased significantly in T2D individuals. A decrease in IgG to MAA-LDL, Rgp44 and PCho was detected. RYGB surgery increases the levels of total fecal IgA and decreases fecal natural IgG and IgM antibodies specific to oxLDL. Natural antibodies and IgA are important in maintaining the normal gut homeostasis and first-line defense against microbes, and their production is markedly altered with RYGB surgery.
Assuntos
Diabetes Mellitus Tipo 2 , Derivação Gástrica , Acetaldeído , Diabetes Mellitus Tipo 2/cirurgia , Fezes , Cisteína Endopeptidases Gingipaínas , Hemaglutininas , Humanos , Imunoglobulina A , Imunoglobulina G , Imunoglobulina M , Lipoproteínas LDL , Malondialdeído , Obesidade/cirurgia , FosforilcolinaRESUMO
Natural Abs are produced by B lymphocytes in the absence of external Ag stimulation. They recognise self, altered self and foreign Ags, comprising an important first-line defence against invading pathogens and serving as innate recognition receptors for tissue homeostasis. Natural IgG Abs have been found in newborns and uninfected individuals. Yet, their physiological role remains unclear. Previously, no natural IgG Abs to oxidation-specific epitopes have been reported. Here, we show the cloning and characterisation of mouse IgG mAbs against malondialdehyde acetaldehyde (MAA)-modified low-density lipoprotein. Sequence analysis reveals high homology with germline genes, suggesting that they are natural. Further investigation shows that the MAA-specific natural IgG Abs cross-react with the major periodontal pathogen Porphyromonas gingivalis and recognise its principle virulence factors gingipain Kgp and long fimbriae. The study provides evidence that natural IgGs may play an important role in innate immune defence and in regulation of tissue homeostasis by recognising and removing invading pathogens and/or modified self-Ags, thus being involved in the development of periodontitis and atherosclerosis.
Assuntos
Anticorpos Monoclonais/metabolismo , Imunoglobulina G/metabolismo , Periodontite/imunologia , Porphyromonas gingivalis/fisiologia , Receptores de Reconhecimento de Padrão/metabolismo , Acetaldeído/química , Acetaldeído/metabolismo , Animais , Anticorpos Monoclonais/isolamento & purificação , Células Clonais , Epitopos de Linfócito B/metabolismo , Proteínas de Fímbrias/metabolismo , Cisteína Endopeptidases Gingipaínas/metabolismo , Imunidade Inata , Imunoglobulina G/isolamento & purificação , Lipoproteínas LDL/química , Lipoproteínas LDL/metabolismo , Malondialdeído/química , Malondialdeído/metabolismo , Camundongos , Camundongos Knockout , Oxirredução , Receptores de LDL/genética , Receptores de Reconhecimento de Padrão/isolamento & purificaçãoRESUMO
IgA is the most abundant Ab in the human body. However, most patients with selective IgA deficiency (SIgAD) are asymptomatic. IgM, and to lesser extent IgG Abs, are generally presumed to compensate for the lack of IgA in SIgAD by multiplying and adopting functions of IgA. We used data from the Northern Finland Birth Cohort 1966 to investigate whether SIgAD patients have differences in levels of natural Abs to oxidized epitopes compared with 20 randomly selected healthy controls. First, we screened the saliva and serum samples from the Northern Finland Birth Cohort 1966 cohort (n = 1610) for IgA concentration. We detected five IgA-deficient subjects, yielding a prevalence of 0.3%, which is consistent with the general prevalence of 0.25% in the Finnish population. To detect natural Abs, we used malondialdehyde acetaldehyde-low-density lipoprotein (MAA-LDL), an Ag known to bind natural Abs. In this study, we show that natural secretory IgM and IgG Abs to MAA-DL were significantly increased in subjects with SIgAD. Given that secretory IgA is an important part of mucosal immune defense and that, in the gut microbiota, dysbiosis with SIgAD patients has been observed, we characterized the oral bacterial microbiota of the subjects with and without SIgAD using high-throughput 16S rRNA gene sequencing. We found no significant alterations in diversity and composition of the oral microbiota in subjects with SIgAD. Our data suggest that increased levels of secretory natural Abs in patients with SIgAD could be a compensatory mechanism, providing alternative first-line defense against infections and adjusting mucosal milieu to maintain a healthy oral microbiota.
Assuntos
Microbioma Gastrointestinal/imunologia , Deficiência de IgA/imunologia , Imunoglobulina A/imunologia , Imunoglobulina M/imunologia , Bactérias/genética , Coorte de Nascimento , Estudos de Casos e Controles , Feminino , Finlândia , Humanos , Imunoglobulina G/imunologia , Lipoproteínas LDL/imunologia , Masculino , Malondialdeído/imunologia , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Saliva/imunologiaRESUMO
Atherosclerosis is a chronic inflammatory disease and major cause of mortality worldwide. One of the crucial steps for atherosclerotic plaque development is oxidation of low-density lipoprotein (LDL). Through the oxidation, highly immunogenic epitopes are created and the immune system is activated. Association between atherosclerosis and periodontal diseases is well documented, and one of the main oral pathogens common in periodontitis is Aggregatibacter actinomycetemcomitans (Aa). Heat shock protein 60 (HSP60) is an important virulence factor for Aa bacteria and a strong activator of the immune system. Cross-reactivity of HSP60 and oxidized LDL (OxLDL) antibodies could be a potential mechanism in the progression of atherosclerosis and one possible link between atherosclerosis and periodontitis. Human plasma samples from neonates and mothers were analyzed to determine if antibody titer to Aa-HSP60 protein is already present in newborns. Further objectives were to characterize antibody response in Aa-HSP60 immunized mice and to determine possible antibody cross-reaction with oxidized LDL. We demonstrated that newborns already have IgM antibody levels to Aa-HSP60. We also showed that in mice, Aa-HSP60 immunization provoked IgG and IgM antibody response not only to Aa-HSP60 but also to malondialdehyde acetaldehyde-modified LDL (MAA-LDL). Competition assay revealed that the antibodies were specific to Aa-HSP60 and cross-reacted with MAA-LDL. Our results suggest a possibility of molecular mimicry between Aa-HSP60 and MAA-LDL, making it intriguing to speculate on the role of HSP60 protein in atherosclerosis that manifests at young age.
Assuntos
Aggregatibacter actinomycetemcomitans/metabolismo , Chaperonina 60/imunologia , Imunidade Humoral , Lipoproteínas LDL/imunologia , Aggregatibacter actinomycetemcomitans/imunologia , Animais , Reações Antígeno-Anticorpo , Chaperonina 60/genética , Chaperonina 60/metabolismo , Reações Cruzadas , Feminino , Sangue Fetal/metabolismo , Humanos , Imunoensaio , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologiaRESUMO
BACKGROUND: Rare tonsillar granulomas may be caused for example by infections, malignancies or sarcoidosis. Granulomas also occur in inborn errors of immunity (IEI) such as common variable immunodeficiency (CVID) with B cell maturation defects and hypogammaglobulinemia. CVID shares various features with sarcoidosis and drug-induced secondary hypogammaglobulinemia; careful consideration of differential diagnosis between these conditions is warranted. CASE PRESENTATION: A 29-year-old female with epilepsy developed dysphagia, dyspnea and impaired exercise tolerance. Obstruction caused by swollen lingual tonsil and edema in the epiglottis and arytenoid mucosa were found. Lingual tonsil and epiglottis biopsies displayed non-necrotizing granulomas. There was no evidence of viral, bacterial, mycobacterial or fungal infections. Chest X-ray, computerized tomography of chest and ultrasound of neck and abdomen remained unremarkable. Positron emission tomography/computed tomography (PET/CT) showed laryngeal enhancement. Empiric antimicrobials combined with prednisolone were insufficient to control her disease. In immunological evaluation, the patient had normal counts of B and T cells. Proportions of CD27+ memory B cells (30.3%) and IgD-IgM-CD27+ switched memory B cells (7.2%; normal range 6.5-29.2%) were normal. Percentage of activated CD21low B cells was high (6.6%; normal range 0.6-3.5%). IgG (3.5 g/L; normal range 6.77-15.0 g/l) and all IgG subclass concentrations were low. Anti-polysaccharide responses were impaired, with 3/10 serotypes reaching a level of 0.35 µg/ml after immunization with Pneumovax®. The findings were consistent with hypogammaglobulinemia resembling CVID, possibly secondary to antiepileptic medication. Her dyspnea and dysphagia responded favorably to subcutaneous IgG and rituximab. CONCLUSIONS: Tonsillar granulomas can be the presenting and only clinical feature of B cell deficiency, highlighting the diversity of symptoms and findings in primary or secondary immunodeficiencies.
RESUMO
BACKGROUND: Pneumococcus is a leading cause of childhood pneumonia worldwide. Pneumococcal conjugate vaccines (PCV) have demonstrated efficacy against childhood invasive pneumococcal disease (IPD) and pneumonia in the United States and Africa. No information is available from Asia on the impact of PCV on childhood pneumonia. METHODS: We conducted a randomized, placebo-controlled, double-blind trial in Bohol, the Philippines (ISRCTN 62323832). Children 6 weeks to <6 months of age were randomly allocated to receive 3 doses of either an 11-valent PCV (11PCV, sanofi pasteur, Lyon, France) or a saline placebo, with a minimum interval of 4 weeks between doses to determine vaccine efficacy (VE) against the primary outcome of a child experiencing first episode of community-acquired radiologically defined pneumonia in the first 2 years of life. Secondary end points were clinical pneumonia, IPD, safety, and immunogenicity. RESULTS: Twelve thousand one hundred ninety-one children were enrolled. By per protocol (PP) analysis, 93 of 6013 fully vaccinated 11PCV recipient children had a first episode of radiologic pneumonia compared with 120 of 6018 placebo recipients. VE against radiologically defined pneumonia for the PP cohort of children 3 to 23 months old was 22.9% (95% CI: -1.1, 41.2; P = 0.06), for the prespecified subgroups of children 3 to 11 months of age, 34.0% (95% CI: 4.8, 54.3; P = 0.02), and of those 12 to 23 months old, 2.7% (95% CI: -43.5, 34.0; P = 0.88). By intent-to-treat (ITT) analysis, 119 of 6097 11PCV recipient children had an episode of radiologic pneumonia compared with 141 of 6094 placebo recipients. VE against radiologic pneumonia for the ITT cohort of children <2 years old was 16.0% (95% CI -7.3, 34.2; P = 0.16), for a subgroup of children <12 months of age, 19.8% (95% CI: -8.8, 40.8; P = 0.15). VE against clinical pneumonia by PP was not significant (VE 0.1%; 95% CI -9.4, 8.7; P = 0.99). IPD was rare: only 3 cases of IPD due to vaccine serotypes were observed during the study. 11PCV was immunogenic and well tolerated. Among 11PCV recipients, a small excess of serious adverse respiratory events was observed in the first 28 days after the first and second dose of vaccine, and of nonrespiratory events after the first dose. An excess of pneumonia episodes in 11PCV recipients in the month following the second dose of vaccination was the principal reason for lower VE by ITT analysis than by PP analysis. CONCLUSIONS: In PP analysis, a 22.9% reduction of community-acquired radiologically confirmed pneumonia in children younger than 2 years of age in the 11-valent tetanus-diphtheria toxoid-conjugated PCV vaccinated group was observed; a reduction similar as observed in other PCV trials. We could not demonstrate any VE against clinical pneumonia. Our finding confirms for the first time that in a low-income, low-mortality developing country in Asia, at least one-fifth of radiologically confirmed pneumonia is caused by pneumococcus, and thus preventable by PCV. Whether PCV should be included in national program in such settings, however, depends on careful country specific disease burden measurement and cost-effectiveness calculation.
Assuntos
Vacinas Pneumocócicas , Pneumonia Pneumocócica/prevenção & controle , Anticorpos Antibacterianos/sangue , Método Duplo-Cego , Humanos , Imunização Secundária , Imunoglobulina G/sangue , Lactente , Filipinas/epidemiologia , Vacinas Pneumocócicas/efeitos adversos , Vacinas Pneumocócicas/imunologia , Pneumonia Pneumocócica/diagnóstico por imagem , Pneumonia Pneumocócica/epidemiologia , Modelos de Riscos Proporcionais , Radiografia , Vacinas Conjugadas/efeitos adversos , Vacinas Conjugadas/imunologiaRESUMO
BACKGROUND: Phosphatidylethanol (PEth) is a promising new marker for detecting long-term alcohol abuse with excellent sensitivity and specificity. Current methods are based on the high performance liquid chromatography-mass spectrometric method and therefore require high levels of expertise and expensive instrumentation. This study was designed to generate PEth-specific monoclonal antibodies for PEth immunoassay development. METHODS: C57/BL6 mice were immunized with PEth in 3 different carriers, mouse serum albumin, mouse high-density lipoproteins, and human low-density lipoprotein (LDL). Mouse splenocytes were fused with a mouse myeloma cell line using the hybridoma technique. Mouse IgM-producing cell lines were selected by limiting dilutions. Binding characteristics of the anti-PEth antibodies were studied using luminometric immunoassays and sequence analysis of the variable region mRNA sequences of the antibodies. Produced antibodies were purified by chromatographic methods. PEth was detected with these antibodies in fluorescence immunoassay and flow cytometric analysis. RESULTS: We generated monoclonal cell lines (2B1 and 2E9) that produce IgM antibodies binding specifically to PEth but not to structurally or chemically similar phospholipids, such as phosphatidylcholine, phosphatidic acid, and cardiolipin. We show here that these anti-PEth antibodies can be used to detect PEth in a fluorescent PEth assay and FACS analysis of human red blood cell samples spiked with PEth. CONCLUSIONS: The present study shows that PEth-specific monoclonal antibodies can be generated using traditional hybridoma technique. Immunogenicity of PEth was enhanced using human LDL as an immunization carrier. The generated monoclonal anti-PEth antibodies, 2B1 and 2E9 bind to PEth in fluid phase and in biological membranes.
Assuntos
Alcoolismo/diagnóstico , Anticorpos Monoclonais/biossíntese , Biomarcadores/análise , Glicerofosfolipídeos/análise , Glicerofosfolipídeos/imunologia , Imunoensaio , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Sequência de Bases , Linhagem Celular , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Hibridomas/imunologia , Imunização , Imunoglobulina M/biossíntese , Região Variável de Imunoglobulina/genética , Lipoproteínas HDL , Lipoproteínas LDL , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/química , Análise de Sequência de RNARESUMO
Treatment of periodontitis has beneficial effects on systemic inflammation markers that relate to progression of atherosclerosis. We aimed to investigate whether immunization with A hemagglutinin domain (Rgp44) of Porphyromonas gingivalis (Pg), a major etiologic agent of periodontitis, would lead to an antibody response cross-reacting with oxidized low-density lipoprotein (OxLDL) and how it would affect the progression of atherosclerosis in low-density lipoprotein receptor-deficient (LDLR-/-) mice. The data revealed a prominent IgM but not IgG response to malondialdehyde-acetaldehyde modified LDL (MAA-LDL) after Rgp44 and Pg immunizations, implying that Rgp44/Pg and MAA adducts may share cross-reactive epitopes that prompt IgM antibody production and consequently confer atheroprotection. A significant negative association was observed between atherosclerotic lesion and plasma IgA to Rgp44 in Rgp44 immunized mice, supporting further the anti-atherogenic effect of Rgp44 immunization. Plasma IgA levels to Rgp44 and to Pg in both Rgp44- and Pg-immunized mice were significantly higher than those in saline control, suggesting that IgA to Rgp44 could be a surrogate marker of immunization in Pg-immunized mice. Distinct antibody responses in plasma IgA levels to MAA-LDL, to Pg lipopolysaccharides (Pg-LPS), and to phosphocholine (PCho) were observed after Rgp44 and Pg immunizations, indicating that different immunogenic components between Rpg44 and Pg may behave differently in regard of their roles in the development of atherosclerosis. Immunization with Rgp44 also displayed atheroprotective features in modulation of plaque size through association with plasma levels of IL-1α whereas whole Pg bacteria achieved through regulation of anti-inflammatory cytokine levels of IL-5 and IL-10. The present study may contribute to refining therapeutic approaches aiming to modulate immune responses and inflammatory/anti-inflammatory processes in atherosclerosis.
Assuntos
Adesinas Bacterianas/imunologia , Anticorpos Antibacterianos/biossíntese , Proteínas de Bactérias/imunologia , Cisteína Endopeptidases/imunologia , Imunoglobulina M/biossíntese , Lipoproteínas LDL/imunologia , Porphyromonas gingivalis/imunologia , Acetaldeído/análogos & derivados , Adesinas Bacterianas/química , Animais , Anticorpos Antibacterianos/metabolismo , Aterosclerose/etiologia , Aterosclerose/imunologia , Aterosclerose/prevenção & controle , Proteínas de Bactérias/química , Infecções por Bacteroidaceae/complicações , Infecções por Bacteroidaceae/imunologia , Infecções por Bacteroidaceae/microbiologia , Reações Cruzadas , Cisteína Endopeptidases/química , Modelos Animais de Doenças , Feminino , Cisteína Endopeptidases Gingipaínas , Humanos , Imunização , Imunoglobulina M/metabolismo , Lectinas/química , Lectinas/imunologia , Lipoproteínas LDL/química , Malondialdeído/análogos & derivados , Malondialdeído/imunologia , Camundongos , Camundongos Knockout , Periodontite/complicações , Periodontite/imunologia , Periodontite/microbiologia , Domínios Proteicos , Receptores de LDL/deficiência , Receptores de LDL/genéticaRESUMO
OBJECTIVE: Tetracycline derivatives affect many cellular functions relevant to chronic cardiovascular pathologies, including cell proliferation, migration and matrix remodelling. Accordingly, we sought to determine whether they may modulate the pathologic characteristics known to be significantly involved in human aortic valve stenosis, such as gelatinase production, apoptosis, expression of vascular endothelial growth factor (VEGF) and tumour necrosis factor-alpha (TNF-alpha). METHODS: The effects of tetracycline derivatives (tetracycline and CMTs-3, -5, -8) on MMP-2 and -9 and their endogenous tissue inhibitor (TIMP-1 and -2) production profiles in explanted human aortic valve pieces were examined by means of gelatine zymography and reverse zymography. Chemiluminescent ELISA was performed to assess VEGF and TNF-alpha concentrations in the medium, and in order to evaluate programmed cell death, in situ labelling of the 3'-ends of the DNA fragments generated by apoptosis-associated endonucleases was performed. RESULTS: CMT-3 and -8 lowered the MMP-9 and VEGF levels significantly in a drug-, dose-, and time-dependent manner. MMP-2 and TIMPs remained unchanged, emphasizing the specificity of CMTs to MMP-9 production on the one hand and restoring the beneficial equilibrium of MMP-9 and TIMPs on the other. Tetracycline was the only drug with a significant impact on net gelatinolytic activity, suggesting that the effect of tetracycline is more extensive concerning total MMP activity. CONCLUSIONS: Tetracycline derivatives may have therapeutic effects on the pathologic remodellation of advanced human aortic stenosis through the inhibition of MMP-9 and VEGF production.
Assuntos
Estenose da Valva Aórtica/metabolismo , Tetraciclinas/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Estenose da Valva Aórtica/patologia , Apoptose/fisiologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Gelatinases/metabolismo , Humanos , Técnicas In Vitro , Inibidores Teciduais de Metaloproteinases/metabolismoRESUMO
Aims. This study investigated the association of autoantibodies binding to oxidized low-density lipoproteins (oxLDL) in diabetic retinopathy (DR). Methods. Plasma from 229 types 1 and 2 patients with DR including diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) was analysed with ELISA-based assay to determine IgA, IgG, and IgM autoantibody levels binding to oxLDL. The controls were 106 diabetic patients without retinopathy (NoDR) and 139 nondiabetic controls (C). Results. PDR group had significantly higher IgA autoantibody levels than DME or NoDR: mean 94.9 (SD 54.7) for PDR, 75.5 (41.8) for DME (p = 0.001), and 76.1 (48.2) for NoDR (p = 0.008). There were no differences in IgG, IgM, or IgA that would be specific for DR or for DME. Type 2 diabetic patients had higher levels of IgA autoantibodies than type 1 diabetic patients (86.0 and 65.5, resp., p = 0.004) and the highest levels in IgA were found in type 2 diabetic patients with PDR (119.1, p > 0.001). Conclusions. IgA autoantibodies were increased in PDR, especially in type 2 diabetes. The high levels of IgA in PDR, and especially in type 2 PDR patients, reflect the inflammatory process and enlighten the role of oxLDL and its autoantibodies in PDR.
Assuntos
Autoanticorpos/sangue , Retinopatia Diabética/imunologia , Imunoglobulina A/sangue , Lipoproteínas LDL/imunologia , Adulto , Idoso , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/imunologia , Retinopatia Diabética/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Moderate alcohol consumption is associated with an increase in plasma high density lipoprotein (HDL) cholesterol concentration and a decrease in low density lipoprotein (LDL) cholesterol concentration. Changes in the concentration and composition of lipoproteins are estimated to account for more than half of alcohol's protective effect for coronary heart disease. Alcohol intake also affects plasma proteins involved in lipoprotein metabolism: cholesteryl ester transfer protein, phospholipid transfer protein, lecithin:cholesterol acyltransferase, lipoprotein lipase, hepatic lipase, and phospholipases. In addition, alcohol intake may result in acetaldehyde modification of apolipoproteins. Furthermore, "abnormal" lipids, phosphatidylethanol and fatty acid ethyl esters are formed in the presence of ethanol and are associated with lipoproteins in plasma. Ethanol and ethanol-induced modifications of lipids may modulate the effects of lipoproteins on the cells in the arterial wall. The molecular mechanisms involved in these processes are complex, requiring further study to better understand the specific effects of ethanol in the pathogenesis of atherosclerosis. This review discusses the effects of ethanol on lipoproteins and lipoprotein metabolism, as well as the novel effects of lipoproteins on vascular wall cells.
RESUMO
Knowledge of the quality and conformity of antimicrobial resistance data is important for comparing resistance rates regionally and over time. In this study, we have evaluated these features of the Finnish national susceptibility surveillance data for two respiratory tract pathogens, Streptococcus pneumoniae and Haemophilus influenzae. For this purpose internal quality control results for two isolates (S. pneumoniae ATCC 49619 and H. influenzae ATCC 49247) were analyzed from 21 clinical microbiology laboratories over a 3-year period. The results show that standardization of the susceptibility testing methods has proceeded well. The number of protocols used for susceptibility testing has declined (from seventeen methods to two with S. pneumoniae and from eleven to three with H. influenzae) and the reproducibility is good. Nevertheless, we noticed that a few laboratories test and report susceptibility results without defined break-points and even include antimicrobials with questionable therapeutic effect. Another non-compliance with the standard was a lack of a regular control system to verify the attainment of the intended quality of results in some laboratories. Interlaboratory analysis of quality control results is a good way to evaluate the quality and conformity of national resistance data. Finnish laboratories have produced very reproducible and accurate susceptibility results in the pre-EUCAST period, which ended in 2011.
Assuntos
Antibacterianos/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/normas , Haemophilus influenzae/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Azitromicina/farmacologia , Finlândia , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Urinary tract infection (UTI) is the most common diagnosis made in prescribing antimicrobials in long-term care facilities (LTCF). The diagnostic criteria for UTI vary among institutions and prescribers. Our aim was to reduce the inappropriate use of antimicrobials in LTCFs. METHODS: A team comprising infectious disease consultant, infection control nurse, and geriatrician visited all LTCFs for older persons (2,321 patients in 25 primary care hospitals and 39 nursing homes and dementia units) in the Central Finland Healthcare District (population 267,000) during 2004-2005. The site visits consisted of a structured interview concerning patients, ongoing systematic antimicrobials, and diagnostic practices for UTI. Following the visits, regional guidelines for prudent use of antimicrobials in LTCFs were published, and the use of antimicrobials was followed up by an annual questionnaire. RESULTS: The proportions of patients receiving antimicrobials in 2005, 2006, 2007, and 2008 were 19.9%, 16.9%, 16.2%, and 15.4%, respectively. Most of the antibiotics were used for UTI (range by year, 66.6%-81.1%). From 2005 through 2008, the proportion of patients on antibiotic prophylaxis for UTI decreased from 13% to 6%. The decrease was statistically significant in both types of settings. CONCLUSION: The visits and guidelines were associated with a reduction in the usage of antimicrobials. To sustain this, UTI surveillance and close collaboration between infection control experts and LTCFs are crucial.
Assuntos
Antibacterianos/uso terapêutico , Antibioticoprofilaxia/normas , Infecção Hospitalar/tratamento farmacológico , Controle de Infecções/tendências , Infecções Urinárias/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antibioticoprofilaxia/estatística & dados numéricos , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Feminino , Finlândia , Instituição de Longa Permanência para Idosos , Humanos , Assistência de Longa Duração , Masculino , Casas de Saúde , Inquéritos e Questionários , Infecções Urinárias/microbiologia , Infecções Urinárias/prevenção & controleRESUMO
Electrical impedance tomography is a highly unstable problem with respect to measurement and modeling errors. This instability is especially severe when absolute imaging is considered. With clinical measurements, accurate knowledge about the body shape is usually not available, and therefore an approximate model domain has to be used in the computational model. It has earlier been shown that large reconstruction artefacts result if the geometry of the model domain is incorrect. In this paper, we adapt the so-called approximation error approach to compensate for the modeling errors caused by inaccurately known body shape. This approach has previously been shown to be applicable to a variety of modeling errors, such as coarse discretization in the numerical approximation of the forward model and domain truncation. We evaluate the approach with a simulated example of thorax imaging, and also with experimental data from a laboratory setting, with absolute imaging considered in both cases. We show that the related modeling errors can be efficiently compensated for by the approximation error approach. We also show that recovery from simultaneous discretization related errors is feasible, allowing the use of computationally efficient reduced order models.