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1.
Chinese Critical Care Medicine ; (12): 438-441, 2023.
Article in Chinese | WPRIM | ID: wpr-982609

ABSTRACT

Sepsis-associated coagulopathy refers to extensive coagulation activation accompanied by a high risk of bleeding and organ failure. In severe cases, it is manifested as disseminated intravascular coagulation (DIC) and leads to multiple organ dysfunction syndrome (MODS). Complement is an important component of the innate immune system and plays an important role in defending against invasion of pathogenic microorganisms. The early pathological process of sepsis involves excessive activation of the complement system, which forms an extremely complex network through interactions with the coagulation, kinin and fibrinolytic system, amplifying and exacerbating the systemic inflammatory response. In recent years, it has been suggested that uncontrolled complement activation system can exacerbate sepsis-associated coagulation dysfunction or even DIC, indicating the potential value of intervening in the complement system in the treatment of septic DIC, and related research progress is reviewed in this article in order to provide new ideas for the discovery of sepsis-associated coagulopathy therapy drugs.


Subject(s)
Humans , Blood Coagulation Disorders , Complement Activation , Blood Coagulation , Multiple Organ Failure , Sepsis
2.
Acta bioquím. clín. latinoam ; 54(4): 437-453, jul. 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1149033

ABSTRACT

Resumen El sistema del complemento juega un papel central en la inmunidad innata, es una línea de defensa contra patógenos y participa en la homeostasis. La activación anormal del complemento contribuye al desarrollo de patologías de variable severidad, tanto inmunológicas y hematológicas como renales. Entre ellas, las microangiopatías trombóticas (MAT) representan un grupo de enfermedades raras con manifestaciones clínicas comunes caracterizadas por anemia hemolítica no inmune, trombocitopenia y daño de órgano(s) blanco. Si bien la clasificación de las MAT sigue siendo desafiante y no ha sido internacionalmente estandarizada, la descripción de entidades asociadas a anomalías del complemento fue comprobada con la eficiencia de la terapia anticomplemento en los pacientes. Las herramientas de diagnóstico desarrolladas en las últimas décadas son esenciales actualmente para diferenciar las MAT más características del grupo; esto es, la púrpura trombótica trombocitopénica (PTT) y el síndrome urémico hemolítico (SUH). En el presente trabajo se presenta una revisión del funcionamiento del sistema del complemento en condiciones fisiológicas, para poder explicar luego cuáles son las alteraciones del sistema implicadas en el desarrollo de las MAT y describir las herramientas disponibles para detectarlas en el laboratorio.


Abstract The complement system plays a crucial role in the innate immune response, being the first-line defense against pathogens and regulating homeostasis. Uncontrolled complement activation can cause immunologic, hematologic as well as renal syndromes of variable severity. Among them, thrombotic microangiopathies (TMA) represent a group of rare diseases characterised by similar clinical manifestations such as microangiopathic hemolytic anemia (MAHA), peripheral thrombocytopenia and organ injury. Although TMA classification is still challenging and no international consensus has been reached, complement-associated disorders have been described thanks to the efficiency of anti-complement therapy in patients. Diagnostic tools developed in the last decades are essential to differentiate the two most well characterized TMA: thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS). This review will describe how the complement system works in physiological conditions in order to explain how complement abnormalities are involved in TMA, and finally how to detect those anomalies using laboratory tests.


Resumo O sistema do complemento desempenha um papel central na imunidade inata, sendo uma linha de defesa contra patógenos e participando da homeostase. A ativação anormal do complemento contribui para o desenvolvimento de patologias de gravidade variável, como imunológicas, hematológicas e renais. Entre elas, as microangiopatias trombóticas (MAT) representam um grupo de doenças raras com manifestações clínicas comuns caracterizadas por anemia hemolítica não imune, trombocitopenia e lesão de órgão(s) alvo. Embora a classificação das MAT continue sendo desafiadora e não tenha sido padronizada internacionalmente, a descrição de entidades associadas a anomalias do complemento foi comprovada com a eficiência da terapia anticomplemento nos pacientes. As ferramentas de diagnóstico desenvolvidas nas últimas décadas são atualmente essenciais para diferenciar as MAT mais características do grupo, que são a púrpura trombocitopênica trombótica (PTT) e a síndrome hemolítica urêmica atípica (SHU). Neste trabalho, é apresentada uma revisão do funcionamento do sistema de complemento em condições fisiológicas, a fim de explicar posteriormente quais são as alterações do sistema compreendidas no desenvolvimento das MAT, e descrever as ferramentas disponíveis para detectá-las em laboratório.


Subject(s)
Humans , Biomarkers/analysis , Complement Activation/physiology , Thrombotic Microangiopathies/diagnosis , Thrombocytopenia/diagnosis , Atypical Hemolytic Uremic Syndrome/diagnosis , Homeostasis , Anemia, Hemolytic/diagnosis
3.
Med. lab ; 24(1): 24-57, 2020.
Article in Spanish | LILACS, COLNAL | ID: biblio-1097020

ABSTRACT

El trasplante renal constituye la mejor opción de tratamiento para los pacientes con enfermedad renal crónica terminal. La supervivencia del injerto es de gran importancia y puede ser afectada por factores inmunológicos o no inmunológicos; esto unido al número de pacientes en las listas de espera, hace necesario definir estrategias de manejo que permitan tener mejores resultados a largo plazo. Objetivo. Determinar las características clínicas y humorales, y los desenlaces en receptores de trasplante renal o combinado hígado-riñón, altamente sensibilizados, que recibieron profilaxis combinada con inmunoglobulina intravenosa y plasmaféresis en el Hospital San Vicente Fundación, en Colombia. Materiales y métodos. Se realizó un estudio retrospectivo, observacional, descriptivo, que incluyó los pacientes trasplantados entre el 4 de julio de 2010 y el 19 de abril de 2017. Como variables se incluyeron, entre otras, la etiología de la enfermedad renal crónica, el tipo de terapia recibida, y el tiempo en lista de espera en días. Como desenlace se evaluó la presencia de rechazo, el tipo de rechazo, la pérdida del injerto, las complicaciones y la muerte. Resultados. Del total de 25 pacientes, el 100% recibió inmunoglobulina intravenosa y el 84% plasmaféresis. El 12% presentó rechazo del injerto, todos de tipo humoral, y el 20% perdió el injerto. Discusión. A pesar de la gran variedad de protocolos propuestos en la literatura, en esta población especial no se ha establecido un protocolo óptimo de inmunosupresión. El protocolo en nuestra pequeña cohorte no tuvo un impacto negativo en el porcentaje de infecciones postrasplante ni en la pérdida del injerto renal, pero sí redujo el tiempo en las listas de espera; por lo tanto, se requieren estudios adicionales para confirmar los hallazgos encontrados en este estudio


Kidney transplantation is the best treatment option for patients with terminal chronic kidney disease, regardless of the etiology, making graft survival an important feature, which may be affected by immunological or non-immunological factors. This, added to the increasing number of patients on waiting lists, makes it necessary to define management strategies for these patients that allow better long-term results. Objectives. To determine the clinical, humoral and outcome characteristics in highly sensitized recipients of kidney and simultaneous kidneyliver transplant who received combined prophylaxis with intravenous immunoglobulin and plasmapheresis therapy in a Colombian medical center. Materials and methods. A retrospective, observational, descriptive study was carried out that included the transplanted patients between July 4, 2010 and April 19, 2017. Variables included the etiology of chronic kidney disease, the type of therapy received, and waiting time in days, among others. As outcomes, the presence of rejection, type of rejection, graft loss, complications and death were evaluated. Results. From a total of 25 patients, 100% received intravenous immunoglobulin and 84% plasmapheresis. Twelve percent presented graft rejection, all humoral, and 20% lost the graft. Discussion. Despite the great variety of protocols proposed in the literature, an optimal immunosuppression protocol has not been established for this particular population. The protocol in our small cohort did not have a negative impact on the percentage of post-transplant infections nor in the loss of the renal graft, but it did reduce waiting time; therefore, additional studies are required to confirm the findings in this study


Subject(s)
Kidney Transplantation , Plasmapheresis , Complement Activation , Graft Rejection
4.
Acta méd. colomb ; 44(4): 42-44, Oct.-Dec. 2019. tab
Article in English | LILACS, COLNAL | ID: biblio-1124060

ABSTRACT

Abstract Atypical hemolytic-uremic syndrome (aHUS) is a diagnosis of exclusion which should be proposed in cases where there is microangiopathic hemolytic anemia, thrombocytopenia and acute kidney injury. It is associated with mutations which cause dysregulation of the complement system and implies an adverse prognosis and a high risk of progression to chronic kidney disease. Following, we present the case of a patient with aHUS, highlighting the effect and importance of biologic therapy with the monoclonal antibody eculizumab. (Acta Med Colomb 2019; 44. DOI:https://doi.org/10.36104/amc.2019.1301).


Resumen El síndrome hemolítico urémico atípico (SHUa) constituye un diagnóstico de exclusión que debe plantearse ante la presencia de anemia hemolítica microangiopática, trombocitopenia y lesión renal aguda. Está asociado con mutaciones que provocan una disregulación del sistema del complemento e implica un pronóstico adverso y alto riesgo de progresión a enfermedad renal crónica. A continuación, presentamos el caso de un paciente con SHUa resaltando el efecto e importancia de la terapia biológica con el anticuerpo monoclonal eculizumab. (Acta Med Colomb 2019; 44. DOI:https://doi.org/10.36104/amc.2019.1301).


Subject(s)
Male , Adult , Atypical Hemolytic Uremic Syndrome , Complement Activation , Thrombotic Microangiopathies , Kidney Failure, Chronic , Antibodies, Monoclonal
5.
Arch. Health Sci. (Online) ; 26(1): 62-66, 28/08/2019.
Article in Portuguese | LILACS | ID: biblio-1046127

ABSTRACT

Introdução: O sistema complemento é composto por diversas proteínas plasmáticas e é um importante mecanismo de defesa da imunidade inata e adquirida, que exerce funções homeostáticas e fisiológicas, como a remoção de células apoptóticas e complexos imunes. A deficiência neste mecanismo pode ser hereditária ou adquirida, e leva ao aumento da susceptibilidade a doenças infecciosas e não infecciosas, raras e fatais. Objetivo: Descrever as principais causas e consequências da deficiência do sistema complemento e relacioná-las com múltiplas patologias. Material e Métodos: Trata-se de uma revisão bibliográfica narrativa, tendo como base de dados, artigos publicados no Scientific Electronic Library Online (SciELO), National Library of Medicine (PubMed), Medical Literature Analysis and retrieval System Online (MEDLINE), nos últimos 5 anos. Resultados: A associação do complemento e doenças foram observadas em situações de deficiência do sistema complemento, anormalidades na regulação e nas inflamações. Mutações genéticas ou aumento do consumo do complemento levam à ativação imprópria ou excessiva do complemento, podendo conduzir a consequências lesivas e ao desenvolvimento de diversas doenças, como, lúpus eritematoso sistêmico, síndrome urêmica hemolítica atípica, glomerulopatia C3, hemoglobinúria paroxística noturna, glomerulonefrite pós-infecciosas, artrite reumatoide, dentre outras. Conclusão: É evidente a participação do sistema complemento na patogênese e patogenia de diversas doenças. O investimento em pesquisas, que visem ampliar o entendimento do papel do mecanismo do sistema complemento, pode contribuir para o desenvolvimento de intervenções terapêuticas paliativas e ou de cura de diversas doenças, com a consequente melhoria da qualidade de vida dos indivíduos acometidos.


Introduction: The complement system is composed of several plasma proteins and is an important defense mechanism of innate and acquired immunity, which exerts homeostatic and physiological functions, such as the removal of apoptotic cells and immune complexes. Deficiency in this mechanism may be hereditary or acquired, and leads to increased susceptibility to infectious and non-infectious, rare and fatal diseases. Objective: To describe the main causes and consequences of the deficiency of the complement system and to relate them to multiple pathologies. Material and Methods: This is a bibliographical narrative review, based on data published in SciELO (Scientific Electronic Library Online), PubMed (National Library of Medicine), MEDLINE (Medical Literature Analysis and retrieval System Online), last five years. Results:The associations of complement and diseases were observed in situations of deficiency of the complement system, abnormalities in regulation and inflammation. Genetic mutations lead to inappropriate or excessive activation of the complement, as well as increased the consumption of the complement. This can lead to harmful consequences and the development of several diseases, such as systemic lupus erythematosus, atypical hemolytic uremic syndrome, C3 glomerulopathy, nocturnal paroxysmal hemoglobinuria, postpartum glomerulonephritis, infectious diseases, rheumatoid arthritis, among others. Conclusion: The participation of the complement system in the pathogenesis and pathogenesis of several diseases is evident. Investing in research, aimed at broadening the understanding of the role of the complement system mechanism, may contribute to the development of palliative therapeutic interventions and or cure of various diseases, with the consequent improvement in the quality of life of affected individuals.


Subject(s)
Complement System Proteins/deficiency , Disease/etiology , Complement System Proteins/genetics , Complement Activation
6.
Childhood Kidney Diseases ; : 93-99, 2019.
Article in English | WPRIM | ID: wpr-785578

ABSTRACT

C3 glomerulopathy is a renal disorder involving dysregulation of alternative pathway complement activation. In most instances, a membranoproliferative pattern of glomerular injury with a prevalence of C3 deposition is observed by immunofluorescence microscopy. Dense deposit disease (DDD) and C3 glomerulonephritis (C3GN) are subclasses of C3 glomerulopathy that are distinguishable by electron microscopy. Highly electron-dense transformation of glomerular basement membrane is characteristic of DDD. C3GN should be differentiated from post-infectious glomerulonephritis and other immune complex-mediated glomerulonephritides showing C3 deposits.


Subject(s)
Complement Activation , Complement Pathway, Alternative , Dichlorodiphenyldichloroethane , Glomerular Basement Membrane , Glomerulonephritis , Glomerulonephritis, Membranoproliferative , Microscopy, Electron , Microscopy, Fluorescence , Pathology , Prevalence
7.
Blood Research ; : 218-228, 2019.
Article in English | WPRIM | ID: wpr-763074

ABSTRACT

BACKGROUND: Atypical hemolytic uremic syndrome (aHUS) involves dysregulation of the complement system, but whether this also occurs in thrombotic thrombocytopenic purpura (TTP) remains unclear. Although these conditions are difficult to differentiate clinically, TTP can be distinguished by low (<10%) ADAMTS13 activity. The aim was to identify the differences in complement activation products between TTP and aHUS and investigate ADAMTS13 activity as a prognostic factor in aHUS. METHODS: We analyzed patients with thrombotic microangiopathy diagnosed as TTP (N=48) or aHUS (N=50), selected from a Korean registry (N=551). Complement activation products in the plasma samples collected from the patients prior to treatment and in 40 healthy controls were measured by ELISA. RESULTS: The levels of generalized (C3a), alternate (factor Bb), and terminal (C5a and C5b-9) markers were significantly higher (all P<0.01) in the patients than in the healthy controls. Only the factor Bb levels significantly differed (P=0.008) between the two disease groups. In aHUS patients, high normal ADAMTS13 activity (≥77%) was associated with improved treatment response (OR, 6.769; 95% CI, 1.605–28.542; P=0.005), remission (OR, 6.000; 95% CI, 1.693–21.262; P=0.004), exacerbation (OR, 0.242; 95% CI, 0.064–0.916; P=0.031), and disease-associated mortality rates (OR, 0.155; 95% CI, 0.029–0.813; P=0.017). CONCLUSION: These data suggest that complement biomarkers, except factor Bb, are similarly activated in TTP and aHUS patients, and ADAMTS13 activity can predict the treatment response and outcome in aHUS patients.


Subject(s)
Humans , Atypical Hemolytic Uremic Syndrome , Biomarkers , Complement Activation , Complement System Proteins , Enzyme-Linked Immunosorbent Assay , Mortality , Plasma , Purpura, Thrombotic Thrombocytopenic , Thrombotic Microangiopathies
8.
J. bras. nefrol ; 40(1): 77-81, Jan.-Mar. 2018. tab
Article in English | LILACS | ID: biblio-893816

ABSTRACT

ABSTRACT Scleroderma is an autoimmune disease that affects multiple systems. While pathophysiologic mechanisms governing the development of scleroderma are relatively poorly understood, advances in our understanding of the complement system are clarifying the role of complement pathways in the development of atypical hemolytic uremic syndrome and scleroderma renal crisis. The abundant similarities in their presentation as well as the clinical course are raising the possibility of a common underlying pathogenesis. Recent reports are emphasizing that complement pathways appear to be the unifying link. This article reviews the role of complement system in the development of atypical hemolytic uremic syndrome and scleroderma renal crisis, and calls for heightened awareness to the development of thrombotic angiopathy in patients with scleroderma.


RESUMO A esclerodermia é uma doença autoimune que afeta múltiplos sistemas. Embora os mecanismos fisiopatológicos que regem o desenvolvimento da esclerodermia sejam relativamente pouco compreendidos, os avanços em nossa compreensão do sistema do complemento estão esclarecendo o papel das vias do complemento no desenvolvimento da síndrome urêmica hemolítica atípica e da crise renal da esclerodermia. As abundantes semelhanças em sua apresentação, bem como o curso clínico, estão aumentando a possibilidade de uma patogênese subjacente comum. Relatórios recentes estão enfatizando que as vias de complemento parecem ser o link unificador. Este artigo analisa o papel do sistema do complemento no desenvolvimento da síndrome urêmica hemolítica atípica e da crise renal na esclerodermia, e exige maior conscientização para com o desenvolvimento da angiopatia trombótica em pacientes com esclerodermia.


Subject(s)
Humans , Scleroderma, Systemic/immunology , Complement Activation , Acute Kidney Injury/physiopathology , Acute Kidney Injury/immunology , Atypical Hemolytic Uremic Syndrome/physiopathology , Atypical Hemolytic Uremic Syndrome/immunology , Scleroderma, Systemic/physiopathology
9.
Mem. Inst. Oswaldo Cruz ; 113(8): e180120, 2018. tab, graf
Article in English | LILACS | ID: biblio-955114

ABSTRACT

BACKGROUND Melanin production has been associated with virulence in various pathogenic fungi, including Fonsecaea pedrosoi, the major etiological agent for chromoblastomycosis, a subcutaneous fungal disease that occurs in South America. OBJECTIVE The aim of this study was to evaluate the effects of acid-basic extracted F. pedrosoi melanin particles and fungal cell ghosts obtained by Novozym 234 treatment on their ability to activate the human complement system. METHODS The ability of melanin particles and fungal cell ghosts to activate the human complement system was evaluated by complement consumption, immunofluorescence, and enzyme-linked immunosorbent assay (ELISA). FINDINGS Unsensitised melanin particles and melanin ghosts presented complement consumption of 82.67 ± 2.08% and 96.04 ± 1.13%, respectively. Immunofluorescence assays revealed intense deposition of the C3 and C4 fragments on the surface of melanin particles and ghosts extracted from F. pedrosoi. Deposition of the C3, C4, and C5 fragments onto melanin samples and zymosan was confirmed by ELISA. Deposition of small amounts of C1q and C9 onto melanin samples and zymosan was detected by ELISA. CONCLUSION Fonsecaea pedrosoi melanin particles and fungal cell ghosts activated the complement system mainly through an alternative pathway.


Subject(s)
Humans , Ascomycota/chemistry , Complement Activation , Melanins/isolation & purification , Melanins/biosynthesis , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique
10.
J. bras. nefrol ; 39(4): 370-375, Oct.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-893785

ABSTRACT

Abstract Introduction: Membranous nephropathy (MN) is one of the major causes of nephrotic syndrome. The complement system plays a key role in the pathophysiology of MN. Objectives: To identify the complement pathway possibly activated in MN cases and correlate the presence of C4d with more severe clinical and histological markers. Methods: Sixty nine cases from renal biopsy with membranous nephropathy were investigated. The presence of C1q was analyzed by direct immunofluorescence; and expression of C4d by immunohistochemistry. Clinical and epidemiological data were obtained upon biopsy request. Results: The presence of focal segmental glomerulosclerosis, global glomerulosclerosis, vascular lesions and tubulointerstitial fibrosis were collected by anatomopathological report. C4d(+) was found in 58 (84%), and C1q(+) was found in 12 (17%) of the cases. Twelve patients had C4d(+)/C1q(+), 46 had C4d(+)/C1q(-), and 11 patients had C4d(-)/C1q(-), probably indicating the activation of the classical, lectin and alternative pathways, respectively. Conclusion: C4d was associated with increased interstitial fibrosis, but not with clinical markers of poor prognosis. Through the deposition of C4d and C1q we demonstrated that all complement pathways may be involved in MN, highlighting the lectin pathway. The presence of C4d has been associated with severe tubulointerstitial lesions, but not with clinical markers, or can be taken as a universal marker of all cases of MN.


Resumo Introdução: A Glomerulopatia membranosa (GM) é uma das principais causas da síndrome nefrótica. O sistema do complemento desempenha um papel chave na fisiopatologia do GM. Objetivos: Identificar a via do complemento possivelmente ativada nos casos de GM e correlacionar a presença de C4d com marcadores clínicos e histológicos mais graves. Métodos: Foram investigados 69 casos de biópsia renal com GM. A presença de C1q foi analisada por imunofluorescência direta e a expressão de C4d por imunohistoquímica. Dados clínicos e epidemiológicos foram obtidos mediante solicitação de biópsia renal. Resultados: A presença de glomerulosclerose segmentar focal, glomeruloesclerose global, lesões vasculares e fibrose tubulointersticial foi coletada por relato anatomopatológico. C4d (+) foi encontrado em 58 (84%), e C1q (+) foi encontrado em 12 (17%) casos. Doze pacientes tinham C4d (+)/C1q (+), 46 tinham C4d (+)/C1q (-) e 11 pacientes tinham C4d (-)/C1q (-), indicando provavelmente a ativação da via clássica, da lectina e da alternativa, respectivamente. Conclusão: O C4d foi associado ao aumento da fibrose intersticial, mas não com marcador clínico de mau prognóstico. Através da deposição de C4d e C1q, demonstrou-se que todas as vias do complemento podem estar envolvidas em GM, destacando a via da lectina. A presença de C4d tem sido associada a lesões tubulointersticiais graves, mas não com marcadores clínicos, ou pode ser tomada como um marcador universal de todos os casos de GM.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Complement System Proteins/biosynthesis , Glomerulonephritis, Membranous/immunology , Peptide Fragments/biosynthesis , Biomarkers , Complement C4b/biosynthesis , Complement Activation
11.
Arq. Asma, Alerg. Imunol ; 1(2): 183-188, abr.jun.2017. ilus
Article in Portuguese | LILACS | ID: biblio-1380367

ABSTRACT

Nefropatia membranosa idiopática é uma causa de síndrome nefrótica cuja etiopatogenia não está completamente esclarecida. Trata-se de uma doença imunologicamente mediada, na qual a deposição de imunocomplexos decorre da reação antígenoanticorpo in situ, na região subepitelial glomerular. A maioria dos antígenos envolvidos identificados são alvos da IgG4, subclasse predominante em imunofluorescências renais na nefropatia membranosa idiopática, em contraste com as formas secundárias da doença, nas quais IgG1, IgG2 e IgG3 prevalecem. Apesar da IgG4 ser um subtipo de imunoglobulina com baixa capacidade de ativação do complemento, há várias evidências deste envolvimento na glomerulopatia (GMP). Esses dados, em conjunto com achados de depósitos glomerulares de lectina ligadora de manose, um dos principais componentes da via das lectinas do complemento, podem sugerir que tanto a via da lectina como a IgG4 estão envolvidas nesta patologia. Os motivos que desencadeiam a formação dos imunocomplexos e a ativação das vias do complemento nesta doença são incertos. A hipótese mais aceita é a de que a nefropatia membranosa idiopática resulte do conjunto de três condições: presença de proteínas com conformações alteradas que passam a atuar como autoantígenos, anticorpos do tipo IgG4 contra estes antígenos, e susceptibilidade genética. O objetivo foi verificar o possível papel da IgG4 na etiopatogenia da nefropatia membranosa primária segundo o que foi publicado até o momento na base de dados MEDLINE/PubMed, a partir de uma revisão narrativa.


Idiopathic membranous nephropathy is a frequent cause of nephrotic syndrome and its etiopathogenesis is not fully elucidated. In this immune mediated disease, the deposition of immune complexes is the result of an antigen-antibody reaction in situ, in the glomerular subepithelial region. Most of the antigens involved and so far identified are targets of IgG4, a predominant IgG subclass in renal immunofluorescence analysis of idiopathic membranous nephropathy, in contrast with secondary forms of the disease, in which IgG1, IgG2 and IgG3 are prevalent. Even though IgG4 is an immunoglobulin subclass with low complement activation capacity, there is abundant evidence of its involvement in the glomerulopathy. These data, together with findings of glomerular deposition of mannose-binding lectin ­ a major component of the lectin pathway in the complement system ­ may suggest that both the lectin pathway and IgG4 are involved in this pathology. The reasons behind the formation of immune complexes and the activation of complement pathways in this disease are unknown. The most widely accepted hypothesis is that idiopathic membranous nephropathy stems from a combination of three conditions: presence of proteins with altered conformations, which start to act as autoantigens; IgG4 antibodies against these antigens; and genetic susceptibility. The objective of this narrative review was to analyze the possible role of IgG4 in the etiopathogenesis of primary idiopathic membranous nephropathy based on articles published to date in the MEDLINE/PubMed database.


Subject(s)
Humans , Male , Female , Immunoglobulin G , Glomerulonephritis, Membranous , Complement Activation , Autoantigens , Review Literature as Topic , Antigen-Antibody Complex
12.
Experimental & Molecular Medicine ; : e320-2017.
Article in English | WPRIM | ID: wpr-212092

ABSTRACT

The complement system is an innate immune defense machinery comprising components that deploy rapid immune responses and provide efficient protection against foreign invaders and unwanted host elements. The complement system is activated upon recognition of pathogenic microorganisms or altered self-cells by exclusive pattern recognition molecules (PRMs), such as collectins, ficolins and pentraxins. Recent accumulating evidence shows that the different classes of effector PRMs build up a co-operative network and exert synergistic effects on complement activation. In this review, we describe our updated view of the crosstalk between previously unlinked PRMs in complement activation and the potential pathogenic effects during infection and inflammation.


Subject(s)
Collectins , Complement Activation , Complement System Proteins , Inflammation
13.
Chinese journal of integrative medicine ; (12): 101-109, 2016.
Article in English | WPRIM | ID: wpr-310897

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the action of Shen-Fu Injection (SFI) in regulating the expression of the serum complements and inflammatory cytokines synthesized and released in response to the stress of global ischemia accompanying cardiac arrest (CA) and resuscitation.</p><p><b>METHODS</b>Thirty pigs were randomly divided into the sham (n=6) and 3 returns of spontaneous circulation (ROSC) groups (n=24). After 8-min untreated ventricular fibrillation and 2-min basic life support, 24 pigs of the ROSC groups were randomized into three groups (n=8 per group), which received central venous injection of SFI (SFI group), epinephrine (EP group), or saline (SA group). Hemodynamic status and blood samples were obtained at 0, 0.5, 1, 2, 4, 6, 12, and 24 h after ROSC.</p><p><b>RESULTS</b>Serum concentrations of specific activation markers of the complement system C3, C4 and C5b-9 were increased during cardiopulmonary resuscitation through 24 h after ROSC. There were intense changes of various pro-inflammatory cytokines and anti-inflammatory cytokines as early as 0.5 h after CA. Compared with the EP and SA groups, SFI treatment reduced the proinflammatory cytokines levels of interleukin (IL)-6, IL-8 and tumor necrosis factor α (TNF-α, P<0.05), and increased the anti-inflammatory cytokine levels of IL-4 and IL-10 (P<0.05). Further, SFI treatment decreased the values of C3, C4 and C5b-9 compared with the EP and SA groups.</p><p><b>CONCLUSIONS</b>SFI, derived from the ancient Chinese medicine, has significant effects in attenuating post-resuscitation immune dysfunction by modulating the expression of complements and cytokines levels. The current study provided an experimental basis for the clinical application of a potential pharmacologic target for post resuscitation immune dysfunction.</p>


Subject(s)
Animals , Male , Aconitine , Chemistry , Pharmacology , Cardiopulmonary Resuscitation , Complement Activation , Complement System Proteins , Metabolism , Cytokines , Blood , Drugs, Chinese Herbal , Pharmacology , Ginsenosides , Chemistry , Pharmacology , Hemodynamics , Inflammation Mediators , Metabolism , Injections , Models, Animal , Oxygen , Metabolism , Survival Analysis , Sus scrofa
14.
Clinics ; 70(2): 81-86, 2/2015. tab, graf
Article in English | LILACS | ID: lil-741422

ABSTRACT

OBJECTIVES: Many authors recommend posterior cruciate ligament-retaining arthroplasty with the intention to maintain the proprioception properties of this ligament. Preservation of the neuroreceptors and nervous fibers may be essential for retaining the proprioception function of the posterior cruciate ligament. The present study was thus developed to evaluate the presence of neural structures in the posterior cruciate ligament resected during posterior stabilized arthroplasty in osteoarthritis patients. In particular, clinical, radiographic and histological parameters were correlated with the presence or absence of neural structures in the posterior cruciate ligament. METHODS: In total, 34 posterior cruciate ligament specimens were stained with hematoxylin-eosin and Gomori trichrome. An immunohistochemical analysis using antibodies against the S100 protein and neurofilaments was also performed. The presence of neural structures was correlated with parameters such as tibiofemoral angulation, histological degeneration of the posterior cruciate ligament, Ahlbäck radiological classification, age, gender and the histologic pattern of the synovial neurovascular bundle around the posterior cruciate ligament. RESULTS: In total, 67.5% of the cases presented neural structures in the posterior cruciate ligament. In 65% of the cases, the neurovascular bundle was degenerated. Nervous structures were more commonly detected in varus knees than in valgus knees (77% versus 50%). Additionally, severe histologic degeneration of the posterior cruciate ligament was related to neurovascular bundle degeneration. CONCLUSIONS: Severe posterior cruciate ligament degeneration was related to neurovascular bundle compromise. Neural structures were more commonly detected in varus knees. Intrinsic neural structures were detected in the majority of the posterior cruciate ligaments of patients submitted to knee arthroplasty for osteoarthritis. .


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Burns/blood , Burns/pathology , Complement Activation/physiology , /metabolism , /blood , Biomarkers/blood , Burns/metabolism , Enzyme-Linked Immunosorbent Assay , Prognosis
15.
Rio de Janeiro; s.n; 2015. xviii,120 p. ilus, tab, graf.
Thesis in Portuguese | LILACS | ID: lil-781862

ABSTRACT

O Sistema Complemento (SC) desempenha papel importante no controle de infecções atuando na eliminação do patógeno e na regulação da resposta imune. Contudo, uma ativação desregulada do SC gera efeitos deletérios ao hospedeiro, contribuindo para a patogênese de diversas doenças, como na Dengue. Entretanto, o envolvimento do SCna infecção pelo vírus Dengue (DENV) ainda tem vários aspectos a serem investigados. Assim, avaliamos a contribuição do SC na infecção in vitro de monócitos pelo DENV; o perfil de expressão dos Receptores de Complemento (CR) CR1, CR2,CR3, CR4, CD46, CD55 e CD59, e de moléculas de ativação nos monócitos e linfócitos T circulantes de pacientes infectados pelos DENV-1,-2 ou -4 por citometria de fluxo.Dosamos os níveis de SC5b-9 e citocinas em pacientes por ELISA. Avaliamos ainda, a contribuição da ativação do SC na permeabilidade e viabilidade endotelial, utilizando modelo in vitro de células endoteliais (CEs) pela medida da resistência elétrica transendotelial (TEER) e liberação de LDH sobrenadante de culturas. Por fim investigamos a interação DENV-2 com componentes purificados do SC por eletroforesedas proteínas. Como achados principais, observamos diminuição na frequência de monócitos CD14+ expressando CR3, CR4 e CD59 em pacientes comparado aos controles saudáveis. De forma interessante, o bloqueio do CR3 levou à diminuição em cerca de 30 por cento da infecção in vitro pelo DENV-2 em monócitos, sem alterar o fenótipo de ativação ou a ativação da caspase-1 destas células. No entanto, com o bloqueio deCR3, detectamos diminuição na produção de TNF-alfa e IFN-alfa. Não observamos diferença significativa na frequência de linfócitos T expressando CR3, CD46, CD55 eCD59 de em pacientes-Dengue-4...


Subject(s)
Humans , Complement Activation , Dengue/diagnosis , Dengue/epidemiology , Receptors, Complement , Fluorescent Antibody Technique, Indirect
16.
China Journal of Chinese Materia Medica ; (24): 2503-2507, 2015.
Article in English | WPRIM | ID: wpr-284784

ABSTRACT

Allergic reactions caused by traditional Chinese medicine injections (TCMIs) become a greatest concern in the clinic application safety. The integral animal evaluation method commonly used in the preclinical evaluation for allergic reactions of TCMIs was not sensitive, specific, quick and objective in observation indexes. Therefore, more researchers have paid attention to the in vitro test method for evaluating allergic reactions induced by TCMIs. Currently, the methods for evaluating allergic reactions induced by TCMIs are mainly targeted at type I allergic reaction and anaphylactic reaction, with only a few in vitro methods for evaluating type II allergic reaction. In this paper, researchers summarized relevant literatures published about evaluation methods for allergic reactions induced by TCMIs in recent years.


Subject(s)
Animals , Humans , Complement Activation , Drug Hypersensitivity , Diagnosis , Injections , Medicine, Chinese Traditional
17.
Korean Journal of Pediatrics ; : 239-244, 2015.
Article in English | WPRIM | ID: wpr-28898

ABSTRACT

The complement system is part of the innate immune response and as such defends against invading pathogens, removes immune complexes and damaged self-cells, aids organ regeneration, confers neuroprotection, and engages with the adaptive immune response via T and B cells. Complement activation can either benefit or harm the host organism; thus, the complement system must maintain a balance between activation on foreign or modified self surfaces and inhibition on intact host cells. Complement regulators are essential for maintaining this balance and are classified as soluble regulators, such as factor H, and membrane-bound regulators. Defective complement regulators can damage the host cell and result in the accumulation of immunological debris. Moreover, defective regulators are associated with several autoimmune diseases such as atypical hemolytic uremic syndrome, dense deposit disease, age-related macular degeneration, and systemic lupus erythematosus. Therefore, understanding the molecular mechanisms by which the complement system is regulated is important for the development of novel therapies for complement-associated diseases.


Subject(s)
Adaptive Immunity , Antigen-Antibody Complex , Autoimmune Diseases , Autoimmunity , B-Lymphocytes , Complement Activation , Complement Factor H , Complement System Proteins , Glomerulonephritis, Membranoproliferative , Hemolytic-Uremic Syndrome , Immunity, Innate , Lupus Erythematosus, Systemic , Macular Degeneration , Physiology , Regeneration
18.
J. bras. nefrol ; 36(2): 208-220, Apr-Jun/2014. tab, graf
Article in Portuguese | LILACS | ID: lil-714671

ABSTRACT

O grupo de doenças que podem manifestar-se com MAT podem apresentar superposição clínica, dificultando o diagnóstico diferencial. Entre estas ressaltamos a PTT e SHU, sendo que esta última pode ocorrer pela ação de toxinas, doenças sistêmicas, hiperativação da via alterantiva descontrolada por alterações nas proteínas reguladoras desta via (SHUa) e por fim, idiopática. Deve-se proceder a uma série de exames para diferenciá-las. Ressaltando que SHUa é um diagnóstico de exclusão de outras causas de MAT. O tratamento da SHUa com infusão de plasma ou plasmaferese, resulta na maior parte dos casos com boa resposta, especialmente hematológica a curto-prazo, porém é uma doença grave e devastadora e, pode levar a óbito e doença renal crônica terminal. Tratamento com plasma apresenta grande recorrência da doença a longo-prazo e evolução renal desfavorável. Eculizumab, um anticorpo monoclonal anti-C5, tem surgido como uma esperança no prognóstico a curto e a longo-prazo nestes pacientes.


There is a group of diseases that may manifest with thrombotic microangiopathy and present clinical overlap. Among these we emphasize the thrombotic thrombocytopenic purpura and Hemolytic Uremic Syndrome, and the latter can occur by the action of toxins, systemic diseases, overactivation of the alternative complement system pathway, which can occur due to changes in regulatory proteins (atypical HUS) and finally, idiopathic. You must carry out a series of tests to differentiate them. aHUS is a diagnosis of exclusion of other causes of MAT. The treatment of aHUS with plasma therapy, results in most cases with good shortterm response, especially hematological; however, it is a progressive and devastating disease and can lead to death and terminal chronic renal disease. Treatment with plasma displays great recurrence of long-term disease and renal insufficiency. Eculizumab, a monoclonal antibody anti-C5, has been associated with hematological remission, benefits on renal function and no need of plasma therapy.


Subject(s)
Humans , Child , Hemolytic-Uremic Syndrome/diagnosis , Hemolytic-Uremic Syndrome/immunology , Hemolytic-Uremic Syndrome/therapy , Purpura, Thrombotic Thrombocytopenic/diagnosis , Complement Activation , Diagnosis, Differential
19.
Korean Journal of Anesthesiology ; : 481-485, 2014.
Article in English | WPRIM | ID: wpr-86640

ABSTRACT

We experienced a living donor liver transplantation for a 26-month-old girl with complement factor H deficiency. Complement factor H is a plasma protein that regulates the activity of the complement pathway. Complement overactivity induced by complement factor H deficiency is associated with atypical hemolytic uremic syndrome. Liver transplantation can be the proper treatment for this condition. During the liver transplantation of these patients, prevention of the complement overactivation is necessary. Minimizing complement activation, through the use of modalities such as plasma exchange before the surgery and transfusion of fresh frozen plasma throughout the entire perioperative period, may be the key for successful liver transplantation in these patients.


Subject(s)
Child, Preschool , Female , Humans , Complement Activation , Complement Factor H , Complement System Proteins , Hemolytic-Uremic Syndrome , Liver Transplantation , Living Donors , Perioperative Period , Plasma , Plasma Exchange
20.
Laboratory Medicine Online ; : 152-156, 2014.
Article in Korean | WPRIM | ID: wpr-178084

ABSTRACT

BACKGROUND: In vitro levels of complement C3 and C4 proteins are sensitive to storage conditions. To avoid in vitro complement activation when testing is delayed, serum should be frozen at -20degrees C within 2 hr of venipuncture. However, this is impractical in routine laboratory work. Therefore, we investigated alterations in C3 and C4 levels in refrigerated specimens over time and derived formulae to estimate initial levels of complement concentrations in delayed testing. METHODS: Ten fresh specimens were measured for C3 and C4 concentrations and were refrigerated at 4degrees C. We measured C3 and C4 levels in refrigerated samples daily for 4 days using an automated nephelometer (Beckman Coulter Inc., USA). RESULTS: C3 and C4 levels were significantly increased over time in refrigerated specimens (P<0.001, P<0.001, respectively). The increments in C3 and C4 levels were described by the equations: C3 (mg/dL)=3.55x+87.18 (r=0.9909), and C4 (mg/dL)=0.72x+22.3 (r=0.9395), where x=the number of days samples were refrigerated before testing. Increases in C3 and C4 concentrations were described on a percentage basis by the equations: DeltaC3 (%)=4.14x+1.07 (r=0.9903), and DeltaC4 (%)=3.57x+2.48 (r=0.9405). CONCLUSIONS: As the measured C3 and C4 concentrations increased by 3.55 mg/dL (4.1%) and 0.72 mg/dL (3.6%) per day in refrigerated specimens, the levels of C3 and C4 should be adjusted in delayed testing. We proposed that the formulae presented be used to back-calculate initial levels of C3 and C4 concentrations.


Subject(s)
Complement Activation , Complement C3 , Complement C4 , Complement System Proteins , Phlebotomy
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