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1.
Am J Transplant ; 16(1): 325-33, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26280899

RESUMO

Klotho is an anti-aging factor mainly produced by renal tubular epithelial cells (TEC) with pleiotropic functions. Klotho is down-regulated in acute kidney injury in native kidney; however, the modulation of Klotho in kidney transplantation has not been investigated. In a swine model of ischemia/reperfusion injury (IRI), we observed a remarkable reduction of renal Klotho by 24 h from IRI. Complement inhibition by C1-inhibitor preserved Klotho expression in vivo by abrogating nuclear factor kappa B (NF-kB) signaling. In accordance, complement anaphylotoxin C5a led to a significant down-regulation of Klotho in TEC in vitro that was NF-kB mediated. Analysis of Klotho in kidneys from cadaveric donors demonstrated a significant expression of Klotho in pre-implantation biopsies; however, patients affected by delayed graft function (DGF) showed a profound down-regulation of Klotho compared with patients with early graft function. Quantification of serum Klotho after 2 years from transplantation demonstrated significant lower levels in DGF patients. Our data demonstrated that complement might be pivotal in the down-regulation of Klotho in IRI leading to a permanent deficiency after years from transplantation. Considering the anti-senescence and anti-fibrotic effects of Klotho at renal levels, we hypothesize that this acquired deficiency of Klotho might contribute to DGF-associated chronic allograft dysfunction.


Assuntos
Complemento C5a/farmacologia , Função Retardada do Enxerto/etiologia , Glucuronidase/metabolismo , Rejeição de Enxerto/etiologia , Transplante de Rim/efeitos adversos , Complicações Pós-Operatórias , Traumatismo por Reperfusão/etiologia , Injúria Renal Aguda/cirurgia , Animais , Western Blotting , Células Cultivadas , Função Retardada do Enxerto/metabolismo , Função Retardada do Enxerto/patologia , Glucuronidase/genética , Rejeição de Enxerto/metabolismo , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto , Humanos , Técnicas Imunoenzimáticas , Fatores Imunológicos/farmacologia , Proteínas Klotho , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Transplante Homólogo
2.
J Small Anim Pract ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39113158

RESUMO

OBJECTIVES: To describe the clinical features and oncologic outcome for cats with primary rib tumours. MATERIALS AND METHODS: Medical records for cats with surgically treated primary rib tumours from six veterinary referral centres were reviewed. Signalment, preoperative clinical signs, reconstruction technique, and surgical and oncologic outcome were retrieved from medical records or by telephone interview with owners and/or referring veterinarians. RESULTS: Of the eight cats with primary rib tumours, three had hemangiosarcoma, two had osteosarcoma and one cat each had chondrosarcoma, osteochondroma and osteoma. The size of the primary rib mass ranged from 2 × 2 × 1.6 cm to 9 × 7 × 7.5 cm. Three minor and one major complication developed during the immediate post-operative period. Surgery consisted of thoracic wall resection in all cats. All animals survived the procedure and the median time to discharge was 3 days. The survival time for benign tumours was 150 (case 5) and 466 (case 4) days, while for malignant tumours ranged from 105 to 550 days (cases 1 to 3, cases 6 to 8). CLINICAL SIGNIFICANCE: Hemangiosarcoma and osteosarcoma were the most represented primary rib tumours in this cohort of cats. Wide surgical excision and adjuvant chemotherapy is recommended for cats with hemangiosarcoma and osteosarcoma, but the prognosis remains guarded. Prognosis appears to be fair for the other tumour types.

3.
Eur J Clin Microbiol Infect Dis ; 32(9): 1129-33, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23504236

RESUMO

The purpose of this investigation was to evaluate the effectiveness of posterior pharyngeal and nasopharyngeal swabs in identifying and quantifying meningococcal carriage. Two swab samples were obtained from 564 healthy adolescents aged 15-19 years, the first taken from the posterior pharyngeal wall through the mouth and the second through the nose. Bacterial genomic DNA was extracted and screened for Neisseria meningitidis by means of two separate singleplex real-time polymerase chain reactions (real-time PCRs) in order to identify the CtrA and sodC genes. Subsequently, N. meningitidis-positive samples underwent a further singleplex real-time PCR in order to determine the N. meningitidis serogroup, and the DNA was quantified by means of standard curves. Thirty-seven subjects (6.6 %) were found to be carriers of N. meningitidis. The most frequently carried serogroup was serogroup B (15 cases, 40.5 %); serogroups A, Y, X, W135 and Z were found in, respectively, two (5.4 %), five (13.5 %), four (10.8 %), three (8.1 %) and one subject (2.7 %); the serogroup was not identified in seven cases. The detection of carrier status was significantly more frequent using posterior pharyngeal swabs (5.3 % vs. 2.1 %; p = 0.004), which also contained a significantly larger number of N. meningitidis genomic copies (4.91 ± 1.39 vs. 2.50 ± 0.8 log10 genomic copies/mL; p < 0.001). Posterior pharyngeal swabs seem to be better than nasopharyngeal swabs for detecting N. meningitidis carriage in large-scale epidemiological studies because they identify a significantly larger number of pathogen carriers and recover a significantly larger amount of bacterial DNA.


Assuntos
DNA Bacteriano/análise , Infecções Meningocócicas/diagnóstico , Nasofaringe/microbiologia , Adolescente , Carga Bacteriana , Proteínas de Bactérias/genética , Portador Sadio/microbiologia , Técnicas e Procedimentos Diagnósticos , Feminino , Humanos , Masculino , Infecções Meningocócicas/microbiologia , Neisseria meningitidis/genética , Neisseria meningitidis/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
4.
Clin Exp Allergy ; 42(6): 929-35, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22909164

RESUMO

BACKGROUND: Hereditary angioedema (HAE) owing to C1 inhibitor deficiency is an autosomal dominant disorder, characterized by recurrent, potentially life-threatening, localized attacks of tissue swelling. Current treatment involves the infusion of C1 inhibitor protein (C1-INH) isolated from human plasma. OBJECTIVES: This open-label extension to a European, Israeli and Argentinean randomized study (NCT00262301) aimed to investigate the efficacy and safety of recombinant human C1 inhibitor (rhC1-INH) as a first-line treatment following an HAE attack, together with its effect on subsequent attacks. METHODS: An HAE-specific visual analogue scale (VAS) 0-100 mm was used by patients to assess the severity of attack at four anatomical locations. Patients were treated with one, single-vial, fixed-dose of rhC1-INH (2100 U), followed by up to two further vials at the investigators discretion. The primary end-point was the time from first rhC1-INH injection to first onset of relief of symptoms (≥ 20 mm decrease on VAS). Response to treatment was defined as the onset of relief within 4 h. RESULTS: A total of 57 patients were treated for 194 HAE attacks. Overall, sustained relief of symptoms was achieved in 87% of rhC1-INH-treated patients within 4 h of treatment, with 57% of attacks requiring only one vial of rhC1-INH. When categorized by successive attacks experienced by individual patients, the response rate to rhC1-INH treatment was 96%, 83%, 87%, 80% and 80% for attacks 1-5 respectively. Treatment with rhC1-INH was well tolerated, with no discontinuations owing to treatment-emergent adverse events and no adverse events relating to immunogenicity. CONCLUSIONS AND CLINICAL RELEVANCE: Treatment with rhC1-INH provides fast-onset relief for an HAE attack, with a high rate of therapeutic response maintained throughout subsequent attacks.


Assuntos
Angioedemas Hereditários/tratamento farmacológico , Proteína Inibidora do Complemento C1/uso terapêutico , Inativadores do Complemento/uso terapêutico , Adolescente , Adulto , Idoso , Proteína Inibidora do Complemento C1/administração & dosagem , Proteína Inibidora do Complemento C1/efeitos adversos , Inativadores do Complemento/administração & dosagem , Inativadores do Complemento/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
5.
Int J Immunopathol Pharmacol ; 24(4): 1115-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22230421

RESUMO

Acquired angioedema (AAE) with C1 inhibitor deficiency is often associated to B cell lymphoproliferative disorders or autoimmune diseases. We report a case of AAE associated with IgM anti-cardiolipin antibodies, with frequent edematous attacks, that disappeared completely after a slight immunosuppression and danazol therapy.


Assuntos
Angioedema/imunologia , Anticorpos Anticardiolipina/sangue , Proteínas Inativadoras do Complemento 1/deficiência , Imunoglobulina M/sangue , Idoso , Angioedema/diagnóstico , Angioedema/tratamento farmacológico , Azatioprina/uso terapêutico , Proteína Inibidora do Complemento C1 , Danazol/uso terapêutico , Feminino , Humanos , Imunossupressores/uso terapêutico , Ticlopidina/uso terapêutico , Resultado do Tratamento
6.
Transfus Clin Biol ; 28(1): 89-91, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33285299

RESUMO

This study shows clinical efficacy and safety profile of an off-label use of caplacizumab for the treatment of immune-mediated thrombotic thrombocytopenic purpura in a middle-aged obese male patient manifesting aphasia, weakness and unconsciousness. Routine blood tests revealed haemolytic anaemia, severe thrombocytopenia (platelet count=20×109/L) and moderate creatinine increase. Diagnosis was based on the clinical judgement and laboratory determinations (undetectable ADAMTS13 activity and presence of anti-ADAMTS13 antibodies). The patient underwent plasma-exchange and an adjunctive treatment with prednisone (1mg/Kg/day), but the occurrence of a refractory and exacerbated form of disease suggested also using rituximab (375mg/m2 weekly for 4 weeks) and caplacizumab as salvage treatments. The caplacizumab was given at 10mg/day subcutaneously without the first intravenous bolus. Because von Willebrand factor inhibition, platelet count recovery and remission of symptoms were achieved, use of caplacizumab with this scheme appeared to be as effective as the approved one. Although this is an off-label use, this case highlights the potential of this new treatment, in terms of drug's efficacy and safety.


Assuntos
Uso Off-Label , Púrpura Trombocitopênica Trombótica , Anticorpos de Domínio Único , Proteína ADAMTS13 , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/tratamento farmacológico , Troca Plasmática , Púrpura Trombocitopênica Trombótica/tratamento farmacológico , Anticorpos de Domínio Único/uso terapêutico
7.
Clin Nephrol ; 73(1): 36-43, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20040350

RESUMO

BACKGROUND: Mental disorders are frequent in hemodialysis (HD) patients. Depression and anxiety along with physical co-morbidity affect quality of life (QOL). Uremia is associated with inflammation and release of cytokines by lymphomonocytes. Inflammatory cytokines are relevant in depression. The aim of this study was to assess the psychological alterations and QOL in HD patients, and to correlate them with pattern of cytokine production. PATIENTS: 30 HD patients and 20 subjects with CKD Stage I-II K-DOQI. Psychometric tests were administered: 1) Hospital Anxiety and Depression Scale (HADS) composed of an anxiety subscale (HADS-A) and a depression subscale (HADS-D); 2) Kidney Disease Quality of Life (KDQOL) modified, including a cognitive function subscale (KDQOL-CF). Whole blood samples collected at beginning of HD session were diluted with RPMI/heparin and incubated for 24 h in presence of lipopolysaccharide (LPS). IL-1Gamma, IL-6, TNF-alpha and IL-10 were assayed on supernatants and results were normalized per number of lymphomonocytes (ng/106 cells). RESULTS: A depressive mood was more frequent in HD patients (50%) than controls (20%, p < 0.0001). No difference for anxiety (HD = 43%, controls = 45%) was observed. QOL score was significantly lower in HD than controls (p = 0.006) and correlated inversely with HADS total, HADS-A and HADS-D (p < 0.0001). Albumin, Kt/V and phosphate were comparable in patients with or without anxiety or depression. Cytokine production was significantly higher in HD patients than controls (IL-1beta p = 0.05; IL-6 p = 0.010; TNF-alpha p < 0.0001; IL-10, p = 0.0019). HD patients with the HADS-A positive for anxiety showed higher IL-6 production (p = 0.026), while IL-1beta levels were not associated with symptoms of depression. KDQOL-CF correlated inversely with levels of IL-6, TNF-alpha and IL-10. CONCLUSIONS: HD patients have symptoms of depression and anxiety that negatively affect QOL. These symptoms are independent of the efficiency of dialysis and nutritional status. On the contrary, IL-6 is linked to the presence of psychological discomfort in these patients.


Assuntos
Citocinas/sangue , Falência Renal Crônica/psicologia , Qualidade de Vida/psicologia , Diálise Renal/psicologia , Adulto , Idoso , Ansiedade/sangue , Ansiedade/psicologia , Depressão/sangue , Depressão/psicologia , Emoções , Feminino , Humanos , Inflamação/sangue , Inflamação/psicologia , Falência Renal Crônica/sangue , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença , Inquéritos e Questionários
8.
J Small Anim Pract ; 59(7): 415-421, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29665060

RESUMO

OBJECTIVE: To describe the use of a caudal superficial epigastric flap in combination with a full-thickness oral mucosal/submucosal graft for single-stage reconstruction of extensive preputial defects in dogs. MATERIALS AND METHODS: Medical records of dogs with extensive preputial defects either of traumatic origin or derived from tumour excision were reviewed. In all dogs, the prepuce was reconstructed using a full-thickness oral mucosal/submucosal graft combined with a caudal superficial epigastric axial pattern flap during a single surgical procedure. Outcome was assessed by routine clinical examinations for 6 months postoperatively, and through telephone follow-up thereafter. RESULTS: Six dogs were included. The caudal superficial epigastric axial pattern flap healed without complications in all dogs, while the full-thickness oral mucosal/submucosal graft failed in one dog. In this individual the skin flap underwent contracture 30 days after surgery and preputial advancement was required. One dog showed postoperative discomfort during urination, which was successfully managed with a Foley catheter and analgesic administration. Three dogs developed paraphimosis at 30, 80 and 90 days, respectively, and required further surgery. Long-term results were good in all dogs. CLINICAL SIGNIFICANCE: The use of a full-thickness oral mucosal/submucosal graft combined with a caudal superficial epigastric axial pattern flap is feasible for single-stage preputial reconstruction in dogs. Attention should be paid to create a sufficiently large preputial opening, in order to prevent paraphimosis.


Assuntos
Doenças do Cão/cirurgia , Procedimentos de Cirurgia Plástica/veterinária , Procedimentos Cirúrgicos Urológicos Masculinos/veterinária , Animais , Cães , Masculino , Mucosa Bucal/transplante , Parafimose/cirurgia , Parafimose/veterinária , Complicações Pós-Operatórias/veterinária , Procedimentos de Cirurgia Plástica/métodos , Transplante de Pele/métodos , Transplante de Pele/veterinária , Retalhos Cirúrgicos/veterinária , Resultado do Tratamento , Procedimentos Cirúrgicos Urológicos Masculinos/métodos
10.
Kidney Int Suppl ; 41: S221-5, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8320926

RESUMO

The role of the complement system in the induction of cytokine release is controversial. Plasma terminal C complex C5b-9 along with Bb and C4d fragments were evaluated in 22 patients during routine acetate or bicarbonate hemodialysis using cuprophane membranes and hemodiafiltration (HDF) or acetate-free-biofiltration (AFB) using polyacrylonitrile (PAN) membranes. In a subgroup of six uremic patients we also evaluated the release of tumor necrosis factor (TNF alpha) and interleukin-6 (IL-6) from monocytes before and after six subsequent sessions with bicarbonate-cuprophane, HDF and AFB-PAN. At beginning of the dialysis increased plasma C5b-9 levels were found in patients treated by acetate or bicarbonate-cuprophane. Moreover, a rapid significant (P < 0.001) increase of C5b-9 levels occurred in both groups 15 minutes after the onset of the hemodialysis procedure with a plateau at 180 minutes. In contrast, only a slight increase in the plasma C5b-9 levels was observed in patients dialysed with HDF or AFB using PAN membranes. This increase was more pronounced with HDF at 0 minutes compared with controls. A positive linear correlation was found in all patients between C5b-9 generation and plasma Bb levels at different times in the dialysis session. The production of C4d fragment remained unchanged in all groups, indicating that C5b-9 complex generation is due to the prevalent alternative complement pathway activation. The pattern of cytokine production strictly resembled the complement system activation and C5b-9 generation.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Complexo de Ataque à Membrana do Sistema Complemento/biossíntese , Citocinas/biossíntese , Diálise Renal , Idoso , Materiais Biocompatíveis , Feminino , Hemofiltração , Humanos , Masculino , Membranas Artificiais , Monócitos/fisiologia
11.
G Ital Nefrol ; 19(5): 575-84, 2002.
Artigo em Italiano | MEDLINE | ID: mdl-12439848

RESUMO

Chronic renal failure and haemodialysis patients are prone to develop encephalopathy. The causes of encephalopathy are often unclear. Clinical signs of encephalopathy in the uraemic patient often overlap with several other affections causing neurological disorders. Whenever basal ganglia are anatomically involved, movement disorders arise, including chorea. Some acute and chronic neurological syndromes associated with chronic uraemia have consistently been reported (uraemic encephalopathy, dialysis disequilibrium syndrome, dialysis dementia, nephroangiosclerosis neuropathy and ageing neuropathy). Other clinical conditions in which neurological involvement exists are not so frequent in both haemodialysis patients and in the general population (Wernicke's encefalopathy, Creutzfeldt-Jacob disease). Because of the non specific symptoms and the very heterogeneous aetiology, a careful physical examination should be performed in haemodialysis patients with clinical signs of encephalopathy and the main metabolic alterations should be sought; moreover, central nervous system imaging examination is often appropriate. In case of basal ganglia anatomical involvement, supported by findings of imaging techniques, it is necessary to evaluate individual causes of encephalopathy by means of more accurate tests including analysis of cerebro-spinal fluid, measurement of plasma levels of vitamin B components and laboratory tests searching for more uncommon diseases such as Huntington's chorea and Wilson's disease.


Assuntos
Coreia/etiologia , Diálise Renal/efeitos adversos , Uremia/complicações , Idoso , Anemia Megaloblástica/complicações , Anemia Megaloblástica/tratamento farmacológico , Gânglios da Base/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encefalopatias Metabólicas/complicações , Encefalopatias Metabólicas/diagnóstico , Corpo Estriado/patologia , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/etiologia , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/terapia , Neuropatias Diabéticas/etiologia , Retinopatia Diabética/etiologia , Diagnóstico Diferencial , Resistência a Medicamentos , Disartria/etiologia , Eritropoetina/uso terapêutico , Haloperidol/uso terapêutico , Humanos , Hipertensão/complicações , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Imageamento por Ressonância Magnética , Masculino , Tomografia Computadorizada por Raios X , Uremia/terapia , Complexo Vitamínico B/uso terapêutico , Encefalopatia de Wernicke/diagnóstico
12.
Vet Comp Orthop Traumatol ; 26(5): 408-15, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23800871

RESUMO

Loosening of the acetabular cup is one of the most common complications following total hip replacement and has an incidence rate of 1.8% to 36.8%. The objective of this study was to describe the surgical technique for the application of a cementless acetabular component specifically designed for treatment of cup loosening and preliminary clinical experience. The Kyon revision cup is composed of two components; the first is a perforated titanium outer shell with holes for 2.4 mm titanium screws, which is impacted into the acetabulum after removal of the loose cup and reaming of the acetabulum. It is secured with a variable number of screws. The second component is an inner plain titanium cup with an ultra-high-molecular-weight polyethylene insert, which is impacted into the outer shell to obtain press-fit stability. This revision cup was used in 31 dogs with cup loosening and a minimum follow-up period of six months. There were four intra-operative complications and two postoperative complications. The main intra-operative complication was difficulty inserting the inner cup into the outer shell. Postoperative complications included craniodorsal hip luxation in one dog, which was successfully managed, and cup loosening in another dog, which required explantation of the prosthesis. The main advantage of the revision cup appears to be increased implant stability afforded by screw fixation. Our initial clinical results in 31 dogs were promising; all but one dog had a successful clinical outcome.


Assuntos
Acetábulo/cirurgia , Artroplastia de Quadril/veterinária , Doenças do Cão/cirurgia , Prótese de Quadril/veterinária , Falha de Prótese , Animais , Artroplastia de Quadril/instrumentação , Cães , Feminino , Masculino , Complicações Pós-Operatórias/cirurgia , Desenho de Prótese
16.
Kidney Int ; 70(3): 477-85, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16775601

RESUMO

Mechanisms for human membranous glomerulonephritis (MGN) remain elusive. Most up-to-date concepts still rely on the rat model of Passive Heymann Nephritis that derives from an autoimmune response to glomerular megalin, with complement activation and membrane attack complex assembly. Clusterin has been reported as a megalin ligand in immunodeposits, although its role has not been clarified. We studied renal biopsies of 60 MGN patients by immunohistochemistry utilizing antibodies against clusterin, C5b-9, and phosphorylated-protien kinase C (PKC) isoforms (pPKC). In vitro experiments were performed to investigate the role of clusterin during podocyte damage by MGN serum and define clusterin binding to human podocytes, where megalin is known to be absent. Clusterin, C5b-9, and pPKC-alpha/beta showed highly variable glomerular staining, where high clusterin profiles were inversely correlated to C5b-9 and PKC-alpha/beta expression (P=0.029), and co-localized with the low-density lipoprotein receptor (LDL-R). Glomerular clusterin emerged as the single factor influencing proteinuria at multivariate analysis and was associated with a reduction of proteinuria after a follow-up of 1.5 years (-88.1%, P=0.027). Incubation of podocytes with MGN sera determined strong upregulation of pPKC-alpha/beta that was reverted by pre-incubation with clusterin, serum de-complementation, or protein-A treatment. Preliminary in vitro experiments showed podocyte binding of biotinilated clusterin, co-localization with LDL-R and specific binding inhibition with anti-LDL-R antibodies and with specific ligands. These data suggest a central role for glomerular clusterin in MGN as a modulator of inflammation that potentially influences the clinical outcome. Binding of clusterin to the LDL-R might offer an interpretative key for the pathogenesis of MGN in humans.


Assuntos
Clusterina/metabolismo , Glomerulonefrite Membranosa/metabolismo , Proteína Quinase C-alfa/metabolismo , Proteína Quinase C/metabolismo , Adulto , Idoso , Biópsia , Proteínas Sanguíneas/farmacologia , Células Cultivadas , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Feminino , Seguimentos , Glomerulonefrite Membranosa/patologia , Humanos , Masculino , Fosforilação , Podócitos/efeitos dos fármacos , Podócitos/metabolismo , Podócitos/patologia , Prognóstico , Proteína Quinase C beta , Receptores de LDL/metabolismo
17.
Lab Invest ; 64(4): 508-19, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2016857

RESUMO

IgA immune complexes (IgA-IC) are considered the primary cause of IgA nephropathy. Despite the consistent findings of IgA and frequently C3 glomerular deposits in most patients, the renal histopathologic lesion may vary from mild mesangial involvement to severe sclerosis. In the IgA immune deposits, IgA and C3 are considered to be relatively constant, whereas the composition of the antigen is expected to vary according to its origin. This report explored th possibility that the histopathologic lesion is a function of the antigen in an IgA immune deposit. To test this hypothesis we developed a passive model of IgA nephropathy whereby glomerular IgA deposits can capture, in situ, circulating antigens. In this model, glomerular IgA deposits (IgA/IgA-IC) were induced by administration of a constant amount of IgA anti-dinitrophenyl (antibody) and dinitrophenyl-conjugated IgA anti-phosphorylcholine (PC) as an antigen. The latter also served as antibody to capture, in situ, circulating PC-containing antigens. Mice that received only IgA/IgA-IC developed glomerular IgA and C3 deposits and a focal increase in mesangial cells and matrix, but no evidence of renal damage. A diffuse increase in mesangial cells and matrix developed in mice treated with IgA/IgA-IC and either PC-Ficoll (carbohydrate antigen) or PC conjugate of bovine serum albumin (protein antigen). In contrast, mice that received IgA/IgA-IC and pneumococcal C polysaccharide, a PC-containing antigen, developed severe diffuse mesangial hypercellularity with segmental necrosis and thrombosis. These mice also developed proteinuria and hematuria. Our results demonstrate that the antigen plays a critical role in development of glomerulonephritis associated with IgA-IC.


Assuntos
Complexo Antígeno-Anticorpo/análise , Antígenos de Bactérias/imunologia , Mesângio Glomerular/patologia , Glomerulonefrite por IGA/patologia , Imunoglobulina A/análise , Glomérulos Renais/patologia , Polissacarídeos Bacterianos/imunologia , Animais , Antígenos de Bactérias/administração & dosagem , Complemento C3/análise , Feminino , Imunofluorescência , Mesângio Glomerular/imunologia , Mesângio Glomerular/ultraestrutura , Glomerulonefrite por IGA/imunologia , Imunoglobulina A/imunologia , Glomérulos Renais/imunologia , Glomérulos Renais/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Polissacarídeos Bacterianos/administração & dosagem
18.
Am J Kidney Dis ; 12(5): 433-6, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3055971

RESUMO

Sera from patients with IgA nephropathy (IgAN) have a reduced capacity to solubilize immune complexes. The in vitro complement-mediated solubilization of immune complexes containing IgG (bovine serum albumin [BSA]-anti-BSA) or IgA (DNP29-BSA-anti-DNP) was decreased, despite normal serum levels of complement. The close correlation between low values for complement-mediated solubilization and high serum levels of polymeric IgA and/or IgA rheumatoid factor indicates that these macromolecules interfere with the process. These findings suggest that polymeric IgA produced during stimulation of mucosae specifically interferes with immune complex solubilization. Further studies are necessary to elucidate the mechanisms. The decreased complement-mediated solubilization in patients with IgAN could be responsible for persistently high levels of immune complexes containing IgA or IgG in the circulation and their continual deposition in the mesangium.


Assuntos
Complexo Antígeno-Anticorpo/imunologia , Proteínas do Sistema Complemento/imunologia , Glomerulonefrite por IGA/imunologia , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Humanos , Polímeros
19.
Nephron ; 62(4): 373-81, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1300432

RESUMO

IgA nephropathy is the most common form of primary glomerulonephritis worldwide. About one quarter of patients progress to terminal renal failure 10 years after the apparent clinical onset. Therefore, the disease represents a social problem in terms of number of patients requiring maintenance hemodialysis. Despite the intense research effort devolved to clarify the pathogenesis of IgA nephropathy, the exact relationship linking the several factors involved is still unknown. In this review we analyze the experimental works reported since 1979, when the first animal model of IgA nephropathy was published by Rifai et al. We also discuss the interplay between experimental data and clinical observations to maximize the information gathered from the different animal models. Finally, we report the new insights into the role played by cytokines, growth factors and autacoids.


Assuntos
Glomerulonefrite por IGA/fisiopatologia , Animais , Complexo Antígeno-Anticorpo , Antígenos/imunologia , Ativação do Complemento , Citocinas/fisiologia , Dieta , Modelos Animais de Doenças , Gliadina/imunologia , Substâncias de Crescimento/fisiologia , Humanos , Imunização , Rim/fisiopatologia , Glomérulos Renais/imunologia , Mucosa/imunologia , Viroses/complicações
20.
J Am Soc Nephrol ; 2(10 Suppl): S167-72, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1600132

RESUMO

Immunoglobulin A nephropathy (IgAN) is an immune complex (IC) glomerulonephritis (GN) that represents one of the most common forms of primary glomerular disease. Proliferation of mesangial cells and the increase of mesangial matrix are histological hallmarks of mesangioproliferative GN. Increased serum levels of IgA, polymeric IgA, IgA rheumatoid factor, IgA-IC, and spontaneous or pokeweed mitogen-induced production of IgA by peripheral blood mononuclear cells are major humoral immune alterations reported in IgAN. Recently, we focused on the role of cytokines and growth factors in the mediation of glomerular injury. Platelet-derived growth factor, transforming growth factor beta, interleukin (IL)-1 and IL-6 are expressed by and act on mesangial cells. Increased expression of platelet-derived growth factor was found in both an active model of IgAN and in renal biopsies of patients with proliferative GN. A strict correlation between increased expression of B-chain mRNA and mesangial proliferation was found. Cytokines such as IL-1, interferon gamma, and IL-6, released by infiltrating mononuclear cells or produced locally by mesangial cells, affect the glomerular response to IgA-IC. In a passive murine experimental model of IgAN, IL-1 and interferon gamma increased mesangial hypercellularity, whereas IL-6 was highly pathogenic when associated to IL-1. In conclusion, classical immunological mechanisms in mesangial GN could interact with other pathways involving cytokines and growth factors in the progression of glomerular injury.


Assuntos
Glomerulonefrite por IGA/imunologia , Glomerulonefrite Membranoproliferativa/imunologia , Animais , Citocinas/fisiologia , Glomerulonefrite por IGA/etiologia , Glomerulonefrite por IGA/patologia , Glomerulonefrite Membranoproliferativa/etiologia , Glomerulonefrite Membranoproliferativa/patologia , Substâncias de Crescimento/fisiologia , Humanos
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