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1.
Clin Exp Immunol ; 199(1): 79-87, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31518441

RESUMO

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease that primarily affects the axial skeleton. A predominance of innate versus adaptive immune responses have been reported in axSpA, indicating a prominent autoinflammatory component of the disease. Little is known about the lectin pathway proteins (LPPs) of the complement system in relation to axSpA. We have investigated LPPs in patients with axSpA and control individuals. Plasma samples were obtained from a cross-sectional cohort of 120 patients with a clinical diagnosis of axSpA and from 144 age- and gender-matched controls. The plasma concentrations of 11 LPPs were measured, using sandwich-type time-resolved immunofluorometric assays in patients and controls, and related to clinical diagnosis and disease activity. Three LPPs [H-ficolin (ficolin-3), L-ficolin (ficolin-2) and collectin liver 1 (CL-L1)] were significantly higher in axSpA patients than in controls (P < 0·0001) and one LPP, collectin kidney 1 (CL-K1), was significantly lower (P < 0·0001). Further, combining H- or L-ficolin concentrations above the 75th percentile of the respective H- or L-ficolin concentration measured in controls with human leucocyte antigen (HLA)-B27 positivity yielded axSpA diagnostic specificities of 99/99% and positive likelihood ratios of 68/62, respectively. H-ficolin and L-ficolin plasma concentrations were found to be elevated in axSpA patients regardless of time since diagnosis. H-ficolin and L-ficolin may represent diagnostic biomarkers for patients with axSpA and should be further evaluated. Our results showed no association between disease activity and the measured LPP concentrations. This result might be due to the cross-sectional design, and should be further investigated.


Assuntos
Lectinas/sangue , Espondilartrite/sangue , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Lectina de Ligação a Manose da Via do Complemento/imunologia , Estudos Transversais , Feminino , Antígeno HLA-B27/sangue , Antígeno HLA-B27/imunologia , Humanos , Lectinas/imunologia , Masculino , Pessoa de Meia-Idade , Espondilartrite/diagnóstico , Espondilartrite/imunologia , Espondilartrite/patologia , Ficolinas
2.
Clin Exp Immunol ; 198(1): 94-100, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31104331

RESUMO

Despite improvements in treatment, coronary artery disease is still responsible for one-third of all deaths globally, due predominantly to myocardial infarction (MI) and stroke. There is an important potential in developing new strategies for treatment of patients with these conditions. Inflammation, and in particular the actions of the complement system, has emerged as part of the pathogenesis in reperfusion injury in patients with MI. To further qualify this, we examined the association between the plasma levels of lectin pathway proteins and myocardial end-points, left ventricular ejection fraction (LVEF) and infarct size in a cohort of patients with ST-elevation myocardial infarction (STEMI). A blood sample was drawn the day after percutaneous coronary intervention from 73 patients with STEMI. The primary end-points, LVEF and infarct size, were measured with magnetic resonance imaging 6-9 days after the infarct. Complement pattern-recognition molecules of the lectin pathway (mannan-binding lectin, H-ficolin, L-ficolin and M-ficolin) were analysed along with soluble membrane attack complex (sMAC) and C-reactive protein (CRP) in plasma with immunofluorometric assays <50%. CRP correlated negatively with LVEF, regression coefficient = -0·17 (P = 0·01). None of the lectin pathway proteins correlated to LVEF or infarct size, nor did soluble membrane attack complex (sMAC). There were no differences in plasma levels of these complement proteins when comparing patients with ejection fraction <50% to patients with ejection fraction <50%. Pattern-recognition molecules of the lectin pathway and sMAC do not predict short-term cardiac outcomes after MI.


Assuntos
Coração/fisiopatologia , Lectinas/sangue , Infarto do Miocárdio/sangue , Função Ventricular Esquerda/fisiologia , Biomarcadores/sangue , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Humanos , Lectinas/metabolismo , Lectina de Ligação a Manose/metabolismo , Infarto do Miocárdio/metabolismo , Intervenção Coronária Percutânea/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/metabolismo , Volume Sistólico/fisiologia , Ficolinas
3.
Artigo em Inglês | MEDLINE | ID: mdl-28960583

RESUMO

Elderspeak is often used when talking to older individuals and is characterised by a slower and/or louder speech, a patronising tone, etc. A part of the reason of such communication can be found in the actual context of negative view of ageing. However, the link between view of ageing and elderspeak has never been objectively studied in oncology. Therefore, 40 healthcare professionals (physicians and medical students) record a podcast where they have to explain an endocrine therapy to two fictional patients (40- vs. 70-year old). Results show that when participants explained the treatment to the older patient, they used shorter utterances and made more repetitions. They also evoked fewer side effects such as sexual issues. Moreover, reduction in length of utterances and of word-per-minute rate was observed for older patient when participants have a positive view of ageing but for both patients when they have a negative view of ageing. In conclusion, physicians and medical students used elderspeak when they explained a treatment to older patients. Participants with a more negative view of ageing also unconsciously talked slower and made shorter utterances to a 40 -year-old patient.


Assuntos
Etarismo , Atitude do Pessoal de Saúde , Médicos , Fala , Estereotipagem , Estudantes de Medicina , Adulto , Idoso , Comunicação , Feminino , Humanos , Masculino , Corpo Clínico , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Relações Médico-Paciente , Adulto Jovem
4.
Am J Transplant ; 17(1): 265-271, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27341702

RESUMO

Kidney transplanted patients still have significantly higher mortality compared with the general population. The innate immune system may play an important role during periods, with suppression of the adaptive immune system. In the present study, two soluble pattern recognition molecules of the innate immune system were investigated, collectin liver 1 (CL-L1) and collectin kidney 1 (CL-K1). Potential associations of their pretransplant levels and long-term graft and recipient survival were examined. The levels of CL-L1 and CL-K1 were measured at the time of transplantation in 382 patients (≥17 years) transplanted in 2000-2001. The cohort was subsequently followed until December 31, 2014. Data on patient and graft survival were obtained from the Norwegian Renal Registry. Both high CL-L1 (≥376 ng/mL) and high CL-K1 (≥304 ng/mL) levels were significantly associated with overall mortality in multivariate Cox analyses with hazard ration (HR) 1.50, 95% confidence interval (CI) 1.09-2.07, p = 0.013 and HR 1.43, 95% CI 1.02-1.99, p = 0.038, respectively. Moreover, high CL-K1 levels were significantly associated with cardiovascular mortality. No association between measured biomarkers and death-censored graft loss was found. Finally, there was a significant correlation between these two collectins, r = 0.83 (95% CI 0.80-0.86). In conclusion, CL-L1 and CL-K1 were significantly associated with mortality in kidney transplant recipients.


Assuntos
Doenças Cardiovasculares/mortalidade , Colectinas/metabolismo , Rejeição de Enxerto/mortalidade , Falência Renal Crônica/cirurgia , Transplante de Rim/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/etiologia , Criança , Pré-Escolar , Estudos de Coortes , Lectina de Ligação a Manose da Via do Complemento , Feminino , Seguimentos , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Lactente , Testes de Função Renal , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Taxa de Sobrevida , Adulto Jovem
5.
Clin Exp Immunol ; 188(1): 138-147, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27925159

RESUMO

Since the discovery of the lectin pathway of complement activation, numerous clinical cohorts have been examined for one or more proteins, with the intention of uncovering the functions of the proteins or with the aim of discovering new biomarkers or diagnostic tools. To unveil the abnormal, it is pivotal to know the normal. Our aim was to describe the concentrations of the 11 known proteins of the lectin pathway in serum and plasma and to uncover possible gender differences, age and diurnal variations, which must be taken into account for investigation in different cohorts. We examined the concentrations of all lectin pathway proteins mannan-binding lectin (MBL), H-ficolin, L-ficolin, M-ficolin, collectin-K1, collectin-L1, MBL-associated serine protease 2 (MASP-2), MASP-3, MBL-associated protein of 44 kDa (MAp44) and MAp19 in 300 Danish blood donors in serum and ethylenediamine tetraacetic acid (EDTA) plasma in established assays, and we further developed a new assay to measure MASP-1 in the same samples. We found significant differences in concentrations between serum and plasma for all proteins except for MBL and MASP-3. H-ficolin, M-ficolin and MAp19 displayed convincing diurnal variation. H-ficolin, in particular, halved from morning to the middle of the night. There were gender differences for most proteins, whereas age did not seem to influence concentration. The present study underlines the necessity of considering which material to use, correct matching and a trial design that takes the nature of the protein into account in order for the outcome of cohort studies to have significant relevance.


Assuntos
Ativação do Complemento , Lectina de Ligação a Manose da Via do Complemento/imunologia , Proteínas do Sistema Complemento/imunologia , Ligação Proteica , Fatores Etários , Anticorpos Monoclonais/imunologia , Biomarcadores , Dinamarca , Feminino , Voluntários Saudáveis , Humanos , Masculino , Serina Proteases Associadas a Proteína de Ligação a Manose/antagonistas & inibidores , Serina Proteases Associadas a Proteína de Ligação a Manose/imunologia , Fatores Sexuais
6.
Clin Exp Immunol ; 189(1): 103-112, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28318015

RESUMO

Mounting evidence indicates that adverse activation of the complement system plays a role in the development of diabetic vascular complications. Plasma levels of the complement proteins mannan-binding lectin (MBL) and its associated serine proteases (MASP-1 and MASP-2) are elevated in diabetes. We hypothesized that single nucleotide polymorphisms (SNPs) in the MASP1 gene may contribute to altered plasma levels of the belonging gene products; MASP-1, MASP-3 and mannan-binding lectin-associated protein of 44 kDa (MAp44) in patients with type 2 diabetes. To investigate this, we compared plasma levels of MASP-1, MASP-3 and MAp44 in 100 patients with type 2 diabetes and 100 sex- and age-matched controls. Ten carefully selected SNPs were analysed using TaqMan® genotyping assay. Additionally, we included a streptozotocin-induced diabetes mouse model to directly examine the effect of inducing diabetes on MASP-1 levels. MASP-1 levels were significantly higher among patients with type 2 diabetes compared with healthy controls (P = 0·017). Five SNPs (rs874603, rs72549254, rs3774275, rs67143992, rs850312) in the MASP1 gene were associated with plasma levels of MASP-1, MASP-3 and MAp44. In the diabetes mouse model, diabetic mice had significantly higher MASP-1 levels than control mice (P = 0·003). In conclusion, MASP-1 levels were higher among patients with type 2 diabetes and diabetic mice. The mechanism behind this increase remains elusive.


Assuntos
Composição Corporal , Diabetes Mellitus Tipo 2/sangue , Lectina de Ligação a Manose/sangue , Serina Proteases Associadas a Proteína de Ligação a Manose/análise , Idoso , Animais , Glicemia , Estudos de Casos e Controles , Dinamarca , Diabetes Mellitus Experimental , Feminino , Genótipo , Humanos , Modelos Lineares , Masculino , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Estreptozocina
7.
Diabetes Metab Res Rev ; 33(5)2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28303635

RESUMO

BACKGROUND: Evidence links the lectin pathway of complement activation to diabetic kidney disease. Upon carbohydrate-recognition by pattern-recognition molecules, eg, mannan-binding lectin (MBL), the MBL-associated serine protease (MASP-2) is activated and initiates the complement cascade. The MASP2 gene encodes MASP-2 and the alternative splice product MBL-associated protein 19 (MAp19). Both MAp19 and MASP-2 circulate in complex with MBL. We tested the hypothesis that MAp19 and MASP-2 concentrations predict the risk of incident microalbuminuria. METHODS: Baseline MAp19 and MASP-2 were measured in 270 persons with newly diagnosed type 1 diabetes tracked for incidence of persistent microalbuminuria in a prospective observational 18-year-follow-up study. RESULTS: Seventy-five participants (28%) developed microalbuminuria during follow-up. MBL-associated protein 19 concentrations were higher in participants that later progressed to microalbuminuria as compared with those with persistent normoalbuminuria (268 ng/mL [95% CI, 243-293] vs 236 ng/mL [95% CI, 223-250], P = .02). Participants with MAp19 concentration within the highest quartile of the cohort had an increased risk of microalbuminuria as compared with participants with MAp19 concentration within the combined lower 3 quartiles in unadjusted Cox analysis, hazard ratio 1.86 ([95% CI, 1.17-2.96], P = .009). This remained significant in adjusted models, eg, adjusting for age, sex, HbA1c , systolic blood pressure, urinary albumin excretion, smoking, serum creatinine, and serum cholesterol. MBL-associated serine protease concentration was not associated with incidence of microalbuminuria. CONCLUSIONS: In conclusion, the results show an association between baseline MAp19 concentration and the incidence of microalbuminuria in an 18-year-follow-up study on persons with newly diagnosed type 1 diabetes.


Assuntos
Albuminúria/diagnóstico , Diabetes Mellitus Tipo 1/complicações , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Adolescente , Adulto , Albuminúria/epidemiologia , Albuminúria/metabolismo , Dinamarca/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Estudos Prospectivos , Adulto Jovem
8.
Scand J Immunol ; 84(1): 12-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27104295

RESUMO

The complement system is a part of the innate immune system and is involved in recognition and clearance of pathogens and altered-self structures. The lectin pathway of the complement system is initiated when soluble pattern recognition molecules (PRMs) with collagen-like regions bind to foreign or altered self-surfaces. Associated with the collagen-like stems of these PRMs are three mannan-binding lectin (MBL)-associated serine proteases (MASPs) and two MBL-associated proteins (MAps). The most studied of the PRMs, MBL, is present in serum mainly as trimeric and tetrameric oligomers of the structural subunit. We hypothesized that oligomerization of MBL may influence both the potential to bind to micro organisms and the interaction with the MASPs and MAps, thus influencing the ability to initiate complement activation. When testing binding at 37 °C, we found higher binding of tetrameric MBL to Staphylococcus aureus (S. aureus) than trimeric and dimeric MBL. In serum, we found that tetrameric MBL was the main oligomeric form present in complexes with the MASPs and MAp44. Such preference was confirmed using purified forms of recombinant MBL (rMBL) oligomers, where tetrameric rMBL interacted stronger with all of the MASPs and MAp44, compared to trimeric MBL. As a direct consequence of the weaker interaction with the MASPs, we found that trimeric rMBL was inferior to tetrameric rMBL in activating the complement system. Our data suggest that the oligomeric state of MBL is crucial both for the binding properties and the effector function of MBL.


Assuntos
Proteínas Sanguíneas/metabolismo , Ativação do Complemento , Lectina de Ligação a Manose/metabolismo , Multimerização Proteica , Staphylococcus aureus/fisiologia , Proteínas de Bactérias/metabolismo , Lectina de Ligação a Manose da Via do Complemento , Humanos , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Ligação Proteica
9.
Infection ; 44(3): 365-70, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26498284

RESUMO

Because of global mobility and migration resulting in a growing diversity of the donor pool, the risk for donor-derived tuberculosis in solid organ transplant recipients becomes more and more relevant, even in countries with a low overall tuberculosis incidence. Here, we describe a case series of donor-derived tuberculosis in 2 of 3 solid organ transplant recipients and one medical staff member in Germany resulting in the death of one recipient. This case series highlights the relevance of this topic to clinicians. It advocates for a better communication between organ procurement organizations and transplant centers regarding donor information and transplant recipient outcome. Furthermore, it underpins the necessity for a standardized critical incident reporting system in the german transplant system to improve short- and long-term recipient's safety, health and survival.


Assuntos
Transplante de Órgãos/efeitos adversos , Doadores de Tecidos , Transplantados , Transplantes/microbiologia , Tuberculose , Idoso , Antituberculosos/administração & dosagem , Antituberculosos/uso terapêutico , Feminino , Pessoal de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Tuberculose/transmissão
10.
Clin Exp Immunol ; 180(2): 227-32, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25533914

RESUMO

There is increasing evidence that the complement system plays an important role in diabetes and the development of diabetic vascular complications. In particular, mannan-binding lectin (MBL) levels are elevated in diabetes patients, and diabetes patients with diabetic nephropathy have higher MBL levels than diabetes patients with normal renal function. The MBL-associated serine proteases (MASPs) MASP-1, MASP-2 and MASP-3 and MBL-associated protein MAp44 have not yet been studied in diabetes patients. We therefore measured plasma levels of MASP-1, MASP-2, MASP-3 and MAp44 in 30 children with type 1 diabetes mellitus (T1DM) and 17 matched control subjects, and in 45 adults with T1DM and 31 matched control subjects. MASP-1 and MASP-2 levels were significantly higher in children and adults with T1DM than in their respective control groups, whereas MASP-3 and MAp44 levels did not differ between patients and controls. MASP-1 and MASP-2 levels correlated with HbA1c, and MASP levels decreased when glycaemic control improved. Because MASP-1 and MASP-2 have been shown to interact directly with blood coagulation, elevated levels of these proteins may play a role in the enhanced thrombotic environment and consequent vascular complications in diabetes.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Serina Proteases Associadas a Proteína de Ligação a Manose/imunologia , Adolescente , Adulto , Coagulação Sanguínea/imunologia , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/tratamento farmacológico , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/imunologia , Feminino , Hemoglobinas Glicadas/imunologia , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Trombose/sangue , Trombose/imunologia
11.
Clin Exp Immunol ; 182(2): 132-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26154564

RESUMO

The objective of this study was to explore the involvement of collectin liver 1 (CL-L1) and collectin kidney 1 (CL-K1) and other pattern recognition molecules (PRMs) of the lectin pathway of the complement system in a cross-sectional cohort of systemic lupus erythematosus (SLE) patients. Concentrations in plasma of CL-L1, CL-K1, mannan-binding lectin (MBL), M-ficolin, H-ficolin and L-ficolin were determined in 58 patients with SLE and 65 healthy controls using time-resolved immunoflourometric assays. The SLE patients' demographic, diagnostic, clinical and biochemical data and collection of plasma samples were performed prospectively during 4 months. CL-L1, CL-K1 and M-ficolin plasma concentrations were lower in SLE patients than healthy controls (P-values < 0.001, 0.033 and < 0.001, respectively). H-ficolin concentration was higher in SLE patients (P < 0.0001). CL-L1 and CL-K1 plasma concentrations in the individuals correlated in both patients and controls. Patients with low complement component 3 (C3) demonstrated a negative correlation between C3 and CL-L1 and CL-K1 (P = 0.022 and 0.031, respectively). Patients positive for anti-dsDNA antibodies had lower levels of MBL in plasma than patients negative for anti-dsDNA antibodies (P = 0.02). In a cross-sectional cohort of SLE patients, we found differences in the plasma concentrations of CL-L1, CL-K1, M-ficolin and H-ficolin compared to a group of healthy controls. Alterations in plasma concentrations of the PRMs of the lectin pathway in SLE patients and associations to key elements of the disease support the hypothesis that the lectin pathway plays a role in the pathogenesis of SLE.


Assuntos
Colectinas/imunologia , Lectina de Ligação a Manose da Via do Complemento/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Adolescente , Adulto , Estudos de Coortes , Colectinas/sangue , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Fluorimunoensaio/métodos , Glicoproteínas/sangue , Glicoproteínas/imunologia , Humanos , Lectinas/sangue , Lectinas/imunologia , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/diagnóstico , Lectina de Ligação a Manose/sangue , Lectina de Ligação a Manose/imunologia , Pessoa de Meia-Idade , Adulto Jovem , Ficolinas
12.
Nature ; 456(7222): 624-7, 2008 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-19052624

RESUMO

Interfaces between complex oxides are emerging as one of the most interesting systems in condensed matter physics. In this special setting, in which translational symmetry is artificially broken, a variety of new and unusual electronic phases can be promoted. Theoretical studies predict complex phase diagrams and suggest the key role of the charge carrier density in determining the systems' ground states. A particularly fascinating system is the conducting interface between the band insulators LaAlO(3) and SrTiO(3) (ref. 3). Recently two possible ground states have been experimentally identified: a magnetic state and a two-dimensional superconducting condensate. Here we use the electric field effect to explore the phase diagram of the system. The electrostatic tuning of the carrier density allows an on/off switching of superconductivity and drives a quantum phase transition between a two-dimensional superconducting state and an insulating state. Analyses of the magnetotransport properties in the insulating state are consistent with weak localization and do not provide evidence for magnetism. The electric field control of superconductivity demonstrated here opens the way to the development of new mesoscopic superconducting circuits.

13.
Clin Exp Immunol ; 173(1): 112-20, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23607747

RESUMO

Growing evidence suggests a prominent role of the complement system in the pathogenesis of cardio- and cerebrovascular diseases (CVD). Mannan-binding lectin-associated serine proteases (MASPs) MASP-1 and MASP-2 of the complement lectin pathway contribute to clot formation and may represent an important link between inflammation and thrombosis. MBL-associated protein MAp44 has shown cardioprotective effects in murine models. However, MAp44 has never been measured in patients with CVD and data on MASP levels in CVD are scarce. Our aim was to investigate for the first time plasma levels of MAp44 and MASP-1, -2, -3 concomitantly in patients with CVD. We performed a pilot study in 50 healthy volunteers, in stable coronary artery disease (CAD) patients with one-vessel (n = 51) or three-vessel disease (n = 53) and age-matched controls with normal coronary arteries (n = 53), 49 patients after myocardial infarction (MI) and 66 patients with acute ischaemic stroke. We measured MAp44 and MASP-1 levels by in-house time-resolved immunofluorometric assays. MASP-2 and MASP-3 levels were measured using commercial enzyme-linked immunosorbent assay kits. MASP-1 levels were highest in subacute MI patients and lowest in acute stroke patients. MASP-2 levels were lower in MI and stroke patients compared with controls and CAD patients. MASP-3 and MAp44 levels did not differ between groups. MASP or MAp44 levels were not associated with severity of disease. MASP and MAp44 levels were associated with cardiovascular risk factors including dyslipidaemia, obesity and hypertension. Our results suggest that MASP levels may be altered in vascular diseases. Larger studies are needed to confirm our results and elucidate the underlying mechanisms.


Assuntos
Isquemia Encefálica/sangue , Lectina de Ligação a Manose da Via do Complemento , Doença das Coronárias/sangue , Serina Proteases Associadas a Proteína de Ligação a Manose/análise , Infarto do Miocárdio/sangue , Doença Aguda , Idoso , Isquemia Encefálica/imunologia , Doença das Coronárias/imunologia , Diabetes Mellitus/sangue , Diabetes Mellitus/epidemiologia , Dislipidemias/sangue , Dislipidemias/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Hipertensão/sangue , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/imunologia , Sobrepeso/sangue , Sobrepeso/epidemiologia , Projetos Piloto , Fatores de Risco , Índice de Gravidade de Doença , Fumar/sangue , Fumar/epidemiologia
14.
Scand J Immunol ; 78(2): 181-93, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23672641

RESUMO

In the context of immunity, pattern recognition is the art of discriminating friend from foe and innocuous from noxious. The basis of discrimination is the existence of evolutionarily conserved patterns on microorganisms, which are intrinsic to these microorganisms and necessary for their function and existence. Such immutable or slowly evolving patterns are ideal handles for recognition and have been targeted by early cellular immune defence mechanisms such as Toll-like receptors, NOD-like receptors, RIG-I-like receptors, C-type lectin receptors and by humoral defence mechanisms such as the complement system. Complement is a proteolytic cascade system comprising around 35 different soluble and membrane-bound proteins. It constitutes a central part of the innate immune system, mediating several major innate effector functions and modulating adaptive immune responses. The complement cascade proceeds via controlled, limited proteolysis and conformational changes of constituent proteins through three activation pathways: the classical pathway, the alternative pathway and the lectin pathway, which converge in common effector functions. Here, we review the nature of the pattern recognition molecules involved in complement activation, as well as their close relatives with no or unknown capacity for activating complement. We proceed to examine the composition of the pattern recognition complexes involved in complement activation, focusing on those of the lectin pathway, and arrive at a new model for their mechanism of operation, supported by recently emerging evidence.


Assuntos
Lectina de Ligação a Manose da Via do Complemento/genética , Proteínas do Sistema Complemento/genética , Imunidade Humoral , Receptores de Reconhecimento de Padrão/imunologia , Complexo Antígeno-Anticorpo/genética , Complexo Antígeno-Anticorpo/imunologia , Via Alternativa do Complemento/genética , Via Clássica do Complemento/genética , Regulação da Expressão Gênica , Humanos , Imunidade Inata , Modelos Imunológicos , Multimerização Proteica , Proteólise , Receptores de Reconhecimento de Padrão/genética
15.
Scand J Immunol ; 77(3): 187-94, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23350935

RESUMO

Circulating mannan-binding lectin (MBL) levels are elevated in type 1 diabetes. Further, high MBL levels are associated with the development of diabetic nephropathy. In animals, a direct effect of MBL on diabetic kidney changes is observed. We hypothesized that MBL levels and detrimental complement activation increase as a consequence of diabetes. We measured plasma MBL before and 7 weeks after inducing diabetes by streptozotocin. Mice have two MBLs, MBL-A and MBL-C. Diabetes induction led to an increase in MBL-C concentration, whereas no change during the study was found in the control group. The increase in MBL-C was associated with the increasing plasma glucose levels. In accordance with the observed changes in circulating MBL levels, liver expression of Mbl2mRNA (encoding MBL-C) was increased in diabetes. Mbl1expression (encoding MBL-A) did not differ between diabetic and control animals. The estimated half-life of recombinant human MBL was significantly prolonged in mice with diabetes compared with control mice. Complement activation in plasma and glomeruli did not differ between groups. We demonstrate for the first time that MBL levels increase after induction of diabetes and in parallel with increasing plasma glucose. Our findings support the previous clinical observations of increased MBL in type 1 diabetes. This change may be explained by alternations in both MBL production and turnover.


Assuntos
Ativação do Complemento/imunologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Lectina de Ligação a Manose/imunologia , Animais , Glicemia/imunologia , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/imunologia , Modelos Animais de Doenças , Feminino , Expressão Gênica , Humanos , Insulina/deficiência , Insulina/genética , Insulina/imunologia , Lectina de Ligação a Manose/sangue , Lectina de Ligação a Manose/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Isoformas de Proteínas/sangue , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Clin Exp Immunol ; 167(2): 303-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22236007

RESUMO

The pattern recognition molecules H-ficolin, L-ficolin and M-ficolin bind to micro-organisms. They activate the lectin pathway of complement through mannan-binding lectin (MBL)-associated serine proteases (MASPs). Association between low MBL levels and infections in patients undergoing chemotherapy for haematological diseases has been observed previously. We now examine for MASP-2, MASP-3 and ficolin levels. We assessed the concentration of lectin pathway molecules as risk factors for infection in patients with haematological malignancy undergoing chemotherapy. Samples taken before the initiation of chemotherapy covering 117 chemotherapy cycles in 105 patients were available. MASPs and ficolins were measured by time-resolved immunoflourometric assays and the levels related to parameters of infections. End-points included febrile neutropenia, documented infections, bacteraemia or severe infections. Lower M-ficolin concentrations were found in patients who developed a severe infection: median 0·27 µg/ml compared to 0·47 µg/ml in patients who did not develop a severe infection (P = 0·01). Conversely, MASP-2 was higher in these patients: median 0·53 µg/ml compared to 0·37 µg/ml, respectively (P = 0·008). When considering M-ficolin levels below 0·36 µg/ml as deficient, the time to development of severe infection was shorter in the M-ficolin deficient group: the hazard ratio was 2·60 (95% confidence interval: 1·23-5·49). No associations were revealed between infections and H-ficolin, L-ficolin or MASP-3. Patients with low M-ficolin are more likely to develop severe infections, whereas MASP-2 showed the opposite.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Infecções Bacterianas/etiologia , Neoplasias Hematológicas/sangue , Lectinas/sangue , Serina Proteases Associadas a Proteína de Ligação a Manose/análise , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bacteriemia/sangue , Bacteriemia/etiologia , Bacteriemia/imunologia , Infecções Bacterianas/sangue , Infecções Bacterianas/imunologia , Suscetibilidade a Doenças , Feminino , Glicoproteínas/sangue , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/tratamento farmacológico , Humanos , Imunidade Inata , Hospedeiro Imunocomprometido , Lectinas/fisiologia , Masculino , Serina Proteases Associadas a Proteína de Ligação a Manose/fisiologia , Pessoa de Meia-Idade , Neutropenia/sangue , Neutropenia/induzido quimicamente , Neutropenia/complicações , Estudos Retrospectivos , Ficolinas
17.
Clin Exp Immunol ; 169(1): 38-48, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22670777

RESUMO

The pattern-recognition molecules mannan-binding lectin (MBL) and the three ficolins circulate in blood in complexes with MBL-associated serine proteases (MASPs). When MBL or ficolin recognizes a microorganism, activation of the MASPs occurs leading to activation of the complement system, an important component of the innate immune system. Three proteins are produced from the MASP1 gene: MASP-1 and MASP-3 and MAp44. We present an assay specific for MASP-1, which is based on inhibition of the binding of anti-MASP-1-specific antibody to MASP-1 domains coated onto microtitre wells. MASP-1 was found in serum in large complexes eluting in a position corresponding to ∼600 kDa after gel permeation chromatography in calcium-containing buffer and as monomers of ∼75 kDa in dissociating buffer. The concentration of MASP-1 in donor sera (n = 105) was distributed log-normally with a median value of 11 µg/ml (range 4-30 µg/ml). Serum and citrate plasma levels were similar, while the values in ethylenediamine tetraacetic acid plasma were slightly lower and in heparin plasma were 1·5 times higher than in serum. MASP-1 was present at adult level at 1 year of age, while it was 60% at birth. In normal healthy individuals the level of MASP-1 was stable throughout a 2-month period. After induction of an acute-phase reaction by operation we found an initial short decrease, concomitant with an increase in C-reactive protein levels, followed by an increase, doubling the MASP-1 concentration after 2 days. The present data prepare the ground for studies on the associations of MASP-1 levels with disease.


Assuntos
Reação de Fase Aguda/sangue , Reação de Fase Aguda/imunologia , Lectina de Ligação a Manose da Via do Complemento/imunologia , Serina Proteases Associadas a Proteína de Ligação a Manose/análise , Serina Proteases Associadas a Proteína de Ligação a Manose/imunologia , Adulto , Fatores Etários , Animais , Western Blotting/métodos , Proteína C-Reativa/análise , Cromatografia em Gel/métodos , Neoplasias Colorretais/sangue , Humanos , Imunidade Inata/imunologia , Imunoglobulina G/isolamento & purificação , Lactente , Recém-Nascido , Lectinas/análise , Lectinas/imunologia , Lectina de Ligação a Manose/sangue , Ratos , Ratos Wistar , Ficolinas
18.
Clin Dev Immunol ; 2012: 354894, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23227084

RESUMO

BACKGROUND: Serum levels of the mannose-binding lectin (MBL), which is an activator of the complement system, have been considered as a pathogenic factor in a broad range of diseases, and means of modulating MBL are therefore being evaluated. In this study we examine the effects of weight loss on MBL levels, and in continuation of this if MBL is synthesized in human adipose tissue. METHODS: 36 nondiabetic obese subjects received a very low-calorie diet (VLCD) of 800 kcal/day for 8 weeks. Blood samples were collected at baseline and after VLCD. Furthermore, we measured MBL mRNA levels by the real-time RT-PCR on human adipose tissue compared to liver tissue. RESULTS: The mean body weight was reduced from 106.3 ± 2.6 kg to 92.8 ± 2.4 kg, P < 0.0001. Median MBL at baseline was 746 µg/L (IQR 316-1190) versus 892 µg/L (IQR 336-1511) after 8 weeks, P = 0.23. No correlations were found between weight loss and changes in MBL (r = -0.098, P = 0.57). MBL real-time RT-PCR showed no expression of mRNA in adipose tissue, but as expected a good expression in liver tissue was seen. CONCLUSIONS: MBL levels are not affected by weight loss and MBL is not synthesized in human adipose tissue.


Assuntos
Lectina de Ligação a Manose/sangue , Redução de Peso/fisiologia , Tecido Adiposo/metabolismo , Adulto , Restrição Calórica/métodos , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Lectina de Ligação a Manose/genética , Lectina de Ligação a Manose/metabolismo , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/genética , Obesidade/metabolismo , RNA Mensageiro/genética , Adulto Jovem
19.
Rheumatol Int ; 32(5): 1457-63, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21461857

RESUMO

The innate immune system contributes to the development of rheumatoid arthritis (RA). A potent contributor to such processes is the complement system. The complement system is known to be activated in the inflammatory phases of osteoarthritis (OA). The lectin pathway of the complement system is activated through the recognition of pathogens or altered self-structures by mannan-binding lectin (MBL) or one of the three ficolins in collaboration with MBL-associated serine proteases (MASPs). We assessed the lectin pathway in plasma and synovial fluid (SF) of 27 RA patients and 30 OA patients by measuring MBL, MASP-2, MASP-3, M-ficolin, and H-ficolin. The concentration for all 5 proteins was significantly higher in plasma than in SF (P < 0.001) and the concentration in paired plasma and SF samples correlated in both RA and OA (significance levels between <0.001 and 0.02). The ratio of SF/plasma concentration was for all proteins significantly elevated in RA compared with OA patients (all P < 0.001). The M-ficolin concentration correlated with the neutrophils in both plasma (P = 0.01) and SF (P < 0.001) of RA, and in plasma of 78 controls (P = 0.03). To our knowledge, this is the first report on these proteins in SF, except for MBL where our results are in contrast to the one previous publication. The results support an important physiological role of the neutrophils in determining the M-ficolin levels in both RA and healthy adults. We suggest that quantifications of white blood cells should be included in future clinical investigations of M-ficolin.


Assuntos
Artrite Reumatoide/metabolismo , Proteínas do Sistema Complemento/metabolismo , Lectinas/metabolismo , Osteoartrite/metabolismo , Líquido Sinovial/metabolismo , Adulto , Idoso , Artrite Reumatoide/sangue , Artrite Reumatoide/imunologia , Biomarcadores/metabolismo , Estudos de Casos e Controles , Dinamarca , Feminino , Glicoproteínas/metabolismo , Humanos , Imunidade Inata , Masculino , Lectina de Ligação a Manose/metabolismo , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Pessoa de Meia-Idade , Neutrófilos/imunologia , Neutrófilos/metabolismo , Osteoartrite/sangue , Osteoartrite/imunologia , Líquido Sinovial/imunologia , Ficolinas
20.
Pneumologie ; 66(4): 224-30, 2012 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-22477483

RESUMO

The data on the quality of care of patients with lung cancer in Germany are insufficient. Although the National Lung Cancer Guideline from 2010 provides a good scientific basis for the management of the frequently complex pathways, no evidence exists showing how the relevant guideline recommendations are implemented nationwide or which treatment options generally are chosen in a tumour entity with one of the poorest prognoses. As part of the National Cancer Plan 2008, specific targets have been formulated for the systematic improvement of cancer care in Germany. As a main goal, the national re-organisation and harmonisation of tumor documentation and quality assurance are required for a sustainable improvement in the quality of care. This review article first describes the relevant terms and then examines how the specific targets of the National Cancer Plan have been implemented so far with regard to lung cancer care.


Assuntos
Atenção à Saúde/normas , Documentação/normas , Neoplasias Pulmonares/terapia , Guias de Prática Clínica como Assunto , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Sistema de Registros/normas , Padrão de Cuidado/normas , Alemanha , Humanos , Garantia da Qualidade dos Cuidados de Saúde/métodos
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