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1.
Eur Ann Allergy Clin Immunol ; 47(2): 54-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25781195

RESUMO

OBJECTIVES: The aim of this study was to investigate if co-morbid conditions as hepatitis C virus infection and celiac disease may be associated to undifferentiated connective tissue disease. METHODS: We studied retrospectively and prospectively 52 patients with diagnosis of undifferentiated connective tissue disease, subdivided, according to Vaz criteria, in systemic lupus erythematosus, systemic sclerosis and Sjögren's syndrome-like subgroups. Serological markers of celiac disease as anti-gliadin, anti-endomysium and anti-tissue transglutaminase antibodies were investigated. An esophagogastroduodenoscopy with duodenal biopsy and histological examination was proposed to patients with positive celiac disease serology. In addition antibodies directed to hepatitis C virus and total IgA-antibodies were investigated. RESULTS: Six patients (11,5%) were positive for celiac disease serological tests although two of them were asymptomatic. Four patients underwent an esophagogastroduodenoscopy, showing total or subtotal villous atrophy at duodenal biopsies. Hepatitis C virus serology was negative in all patients and none had IgA deficiency. 83% of celiac patients showed a scleroderma-like phenotype. We observed a statistically higher incidence of autoimmune symptoms in patients with gluten sensitivity. Fatigue and myalgia regressed early after the beginning of gluten-free diet. CONCLUSIONS: In our cohort of patients the prevalence of celiac disease was higher than that reported in the general population. We believe that all patients with diagnosis of undifferentiated connective tissue disease, especially those with a systemic sclerosis-like presentation, should be investigated for celiac disease, even in absence of gastrointestinal symptoms. Gluten-free diet should be early recommended to all patients having undifferentiated connective tissue disease and gluten sensitivity.


Assuntos
Doença Celíaca/epidemiologia , Doenças do Tecido Conjuntivo/epidemiologia , Adulto , Idoso , Autoanticorpos/sangue , Biomarcadores/sangue , Biópsia , Doença Celíaca/sangue , Doença Celíaca/diagnóstico , Doença Celíaca/dietoterapia , Doença Celíaca/imunologia , Comorbidade , Doenças do Tecido Conjuntivo/sangue , Doenças do Tecido Conjuntivo/diagnóstico , Doenças do Tecido Conjuntivo/imunologia , Dieta Livre de Glúten , Duodeno/patologia , Endoscopia Gastrointestinal , Feminino , Hepatite C/epidemiologia , Humanos , Lúpus Eritematoso Sistêmico/epidemiologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Cidade de Roma/epidemiologia , Escleroderma Sistêmico/epidemiologia , Testes Sorológicos , Síndrome de Sjogren/epidemiologia , Adulto Jovem
2.
Genes Immun ; 15(7): 500-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25030430

RESUMO

The host genetic basis of mixed cryoglobulin vasculitis is not well understood and has not been studied in large cohorts. A genome-wide association study was conducted among 356 hepatitis C virus (HCV) RNA-positive individuals with cryoglobulin-related vasculitis and 447 ethnically matched, HCV RNA-positive controls. All cases had both serum cryoglobulins and a vasculitis syndrome. A total of 899 641 markers from the Illumina HumanOmni1-Quad chip were analyzed using logistic regression adjusted for sex, as well as genetically determined ancestry. Replication of select single-nucleotide polymorphisms (SNPs) was conducted using 91 cases and 180 controls, adjusting for sex and country of origin. The most significant associations were identified on chromosome 6 near the NOTCH4 and MHC class II genes. A genome-wide significant association was detected on chromosome 6 at SNP rs9461776 (odds ratio=2.16, P=1.16E-07) between HLA-DRB1 and DQA1: this association was further replicated in additional independent samples (meta-analysis P=7.1 × 10(-9)). A genome-wide significant association with cryoglobulin-related vasculitis was identified with SNPs near NOTCH4 and MHC Class II genes. The two regions are correlated and it is difficult to disentangle which gene is responsible for the association with mixed cryoglobulinemia vasculitis in this extended major histocompatibility complex region.


Assuntos
Crioglobulinas/análise , Hepatite C/complicações , Polimorfismo de Nucleotídeo Único , Vasculite/genética , Estudos de Casos e Controles , Cromossomos Humanos Par 6/genética , Crioglobulinemia/etiologia , Crioglobulinemia/genética , Feminino , Genes MHC da Classe II , Estudo de Associação Genômica Ampla , Humanos , Masculino , Proteínas Proto-Oncogênicas/genética , Receptor Notch4 , Receptores Notch/genética , Vasculite/etiologia
3.
Rheumatology (Oxford) ; 47(11): 1659-63, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18713771

RESUMO

OBJECTIVE: To investigate the contribution of inherited and acquired thrombophilic defects to the clinical manifestations of mixed cryoglobulinaemia vasculitis. METHODS: The following thrombophilic defects were investigated in 64 consecutive patients with HCV-associated mixed cryoglobulinaemia: aPLs, lupus anti-coagulant, homocysteinaemia, protein C and protein S concentrations, activated protein C resistance, plasminogen activator inhibitor-1 4G4G and 5G5G genotypes, and the presence of mutations of factor V (Leiden and H1299R), of prothrombin (G20210A) and of methyl tetrahydrofolate reductase (C677T and A1298C). Additional variables were demographic data, duration of the disease, cryocrit level and vascular risk factors (diabetes, hypertension, hypercholesterolaemia and smoking habit). The following clinical manifestations of mixed cryoglobulinaemia were analysed as dependent covariates: severity of purpura, presence of necrotic skin ulcers, presence of peripheral neuropathy and presence of kidney disease. RESULTS: Logistic regression analysis identified hyperhomocysteinaemia as a risk factor for severe purpura (P < 0.0001) and for the presence of skin ulcers (P < 0.0001), whereas none of the other thrombophilic defects influenced the clinical presentation of mixed cryoglobulinaemia. Purpura improved in two patients after lowering homocysteine with vitamin supplementation. CONCLUSIONS: Hyperhomocysteinaemia may be a risk factor for severe cutaneous manifestations in mixed cryoglobulinaemia.


Assuntos
Crioglobulinemia/complicações , Hiper-Homocisteinemia/complicações , Úlcera Cutânea/etiologia , Vasculite/etiologia , Resistência à Proteína C Ativada , Adulto , Idoso , Estudos de Casos e Controles , Crioglobulinemia/genética , Fator V/genética , Feminino , Humanos , Hiper-Homocisteinemia/genética , Modelos Logísticos , Inibidor de Coagulação do Lúpus/genética , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Protrombina/genética , Fatores de Risco , Pele/irrigação sanguínea , Úlcera Cutânea/genética , Vasculite/genética
4.
Am J Med ; 83(4): 726-30, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3674059

RESUMO

Seven patients with type II idiopathic mixed cryoglobulinemia were treated with recombinant human leukocyte interferon (alpha interferon). In all of them, a conspicuous reduction of circulating cryoglobulins was noted, together with a definite, remarkable improvement of the clinical pattern. The immunologic parameters (natural killer cell activity and phagocytosis, among others) improved as well; side effects were usually mild and transient. Increases in the cryoglobulin level occurred in a few cases, but they were at least partly sensitive to readministration of alpha interferon treatment. The favorable results obtained in these cases of idiopathic cryoglobulinemia seem to be consistent and prolonged.


Assuntos
Crioglobulinemia/terapia , Interferon Tipo I/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Adulto , Idoso , Crioglobulinemia/imunologia , Crioglobulinas/imunologia , Feminino , Humanos , Células Matadoras Naturais/imunologia , Masculino , Pessoa de Meia-Idade , Fagocitose
5.
Am J Med ; 99(4): 386-91, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7573094

RESUMO

PURPOSE: The purpose of this study was to assess whether granulocytopenia observed in 3 of 38 patients with essential mixed cryoglobulinemia who were treated with low-dose interferon was due to the underlying disease or to synergistic toxicity of interferon with other drugs. PATIENTS AND METHODS: Adverse effects of interferon therapy were monitored in 38 patients affected with type II essential mixed cryoglobulinemia. Patients were treated with 3 million units (MU), daily or on alternate days, of recombinant interferon-alpha 2a (35 patients) or with natural interferon-beta (3 patients). The duration of treatment ranged between 6 and 15 months; the total duration of follow-up, including after therapy, ranged between 8 and 93 months. RESULTS: None of 35 patients treated with interferon alone developed significant hematologic alterations. In addition, none of 7 patients treated with angiotensin-converting enzyme (ACE) inhibitors alone showed hematologic toxicity. Three patients who were treated with a combination of interferon and ACE inhibitors developed severe granulocytopenia a few days after starting treatment. Granulocytopenia subsided within 1 to 2 weeks after suspending therapy. Resumption of treatment with this drug combination produced a granulocytopenia relapse in 1 patient. In these 3 patients, interferon treatment alone, or ACE inhibitor monotherapy, was not followed by granulocytopenia. CONCLUSION: Although severe hematologic toxicity rarely develops in patients treated with low-dose interferon, granulocytopenia occurred in all 3 of our patients with mixed cryoglobulinemia who were treated with a combination of low-dose interferon-alpha 2a and ACE inhibitors. Neither drug alone was toxic in any of our cryoglobulinemic patients, indicating a high risk of severe hematologic toxicity for this drug combination, at least in patients with this disease. Physicians should be aware of this danger when using interferon treatment in patients with this, or possibly other, disorder(s) that also require antihypertensive therapy.


Assuntos
Agranulocitose/induzido quimicamente , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Antivirais/efeitos adversos , Crioglobulinemia/tratamento farmacológico , Interferon-alfa/efeitos adversos , Adulto , Idoso , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Antivirais/uso terapêutico , Crioglobulinemia/virologia , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Pessoa de Meia-Idade , Proteínas Recombinantes
6.
J Biol Regul Homeost Agents ; 8(2): 56-9, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7863814

RESUMO

A subset of patients treated with recombinant interferon alpha-2a (rIFN-alpha 2a) for idiopathic mixed cryoglobulinemia (IMC) developed clinical resistance to therapy after a sustained response. Neutralizing antibodies to rIFN-alpha 2a were found in the sera of three out of four such patients, and in none of the patients who remained responsive to treatment. rIFN-alpha 2a neutralizing antibodies appeared in serum samples of the former three patients 1, 5 and 6 months before evidence for clinical resistance, respectively. Antibody titres to rIFN-alpha 2a were consistently higher than those to natural interferon (nIFN). In the fourth patient with clinical resistance, neutralizing antibodies could not be detected by a very sensitive bioassay in any of several serum samples taken before and after relapse. All the four patients could be reinduced into remission by the administration of nIFN-alpha. These data indicate that mechanisms other than the production of neutralizing antibodies can mediate acquired resistance to IFN therapy. Furthermore, both antibody-related and -unrelated resistance can be overcome by switching to different species of IFN-alpha.


Assuntos
Crioglobulinemia/terapia , Interferon-alfa/efeitos adversos , Interferon-alfa/uso terapêutico , Anticorpos/sangue , Crioglobulinemia/imunologia , Resistência a Medicamentos , Humanos , Interferon alfa-2 , Interferon-alfa/imunologia , Testes de Neutralização , Proteínas Recombinantes , Recidiva , Indução de Remissão
7.
Minerva Gastroenterol Dietol ; 48(4): 319-29, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16491057

RESUMO

The delineation of the association of HCV infection with mixed cryoglobulinemia has provided new insight into the etiology and pathogenesis of this extrahepatic manifestation of the infection. Yet very little evidence has been obtained thus far on the specific roles of virus in production of the monoclonal rheumatoid factors responsible for classic type II cryoglobulins and the associated clinical manifestations. The problematic areas of investigation that have in some instances generated misconceptions due to lack of data are reviewed. These include the prevalence and heterogeneity of mixed cryoglobulins; clinical manifestations such as liver cirrhosis, membranoproliferative glomerulonephritis, autoimmunity, progression of cryoglobulinemia from type III to type II, development of B cell malignancies; determination of lineages based on immunoglobulin gene utilization; and the anti-viral treatment of patients with mixed cryoglobulinemia.

8.
Ital Heart J ; 1(7): 487-92, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10933332

RESUMO

BACKGROUND: The aim of this study was to evaluate the incidence of morphologic and functional cardiac abnormalities in patients with systemic lupus erythematosus and correlate the data with antiphospholipid antibody (aPL) levels. METHODS: Ninety-one patients with systemic lupus erythematosus were enrolled and divided into two groups according to the presence (Group 1, n = 45) or absence of aPL (Group 2, n = 46). All patients underwent standard two-dimensional and Doppler echocardiographic examination. aPL were detected by a standardized and validated ELISA test. Five patients with regional ventricular dysfunction also underwent coronary angiography. The chi2 test was used for the statistical analysis of the data. For smaller groups of samples the Fisher's exact test was employed. RESULTS: Pericardial effusion was detected in 19 patients without any statistical difference between the two groups. A valvular involvement was present in 39 patients: a moderate-severe degree was more frequent in Group 1 (p = 0.02). Regional wall motion abnormalities were observed in 8 patients: only 1 in Group 2 and 7 in Group 1 (p = 0.03). Coronary angiography showed normal arteries in all patients of Group 1. CONCLUSIONS: aPL play a role in the pathogenesis of the severity of valvular lesions as well as in regional myocardial dysfunction, suggesting a small vessel disease.


Assuntos
Anticorpos Antifosfolipídeos/sangue , Ecocardiografia , Cardiopatias/complicações , Lúpus Eritematoso Sistêmico/complicações , Adolescente , Adulto , Ecocardiografia Doppler , Ensaio de Imunoadsorção Enzimática , Feminino , Cardiopatias/diagnóstico por imagem , Doenças das Valvas Cardíacas/complicações , Doenças das Valvas Cardíacas/diagnóstico por imagem , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Derrame Pericárdico/complicações , Derrame Pericárdico/diagnóstico por imagem , Estudos Prospectivos , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/diagnóstico por imagem
9.
J Neurol ; 261(4): 725-31, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24500496

RESUMO

Hepatitis C virus (HCV)-related cryoglobulinemia commonly causes disabling complications including peripheral neuropathy and neuropathic pain. In this prospective clinical, neurophysiological, and skin biopsy study we aimed at assessing clinical characteristics and risk factors of peripheral neuropathy and neuropathic pain in patients with HCV-related cryoglobulinemia. We enrolled 69 consecutive patients with HCV-related cryoglobulinemia. We diagnosed neuropathic pain with the DN4 (Neuropathic Pain Diagnostic) questionnaire, and rated the various neuropathic pains with the Neuropathic Pain Symptom Inventory (NPSI). All patients underwent a standard nerve conduction study to assess Aß-fiber function, laser-evoked potentials to assess Aδ-fiber function, and skin biopsy to assess C-fiber terminals. Of the 69 patients studied, 47 had a peripheral neuropathy, and 29 had neuropathic pain. Patients with peripheral neuropathy were older than those without (P < 0.0001). While peripheral neuropathy was significantly associated with the duration of HCV infection (P < 0.01), it was unrelated to the duration of cryoglobulinemia and cryocrit (P > 0.5). The severity of peripheral neuropathy significantly correlated with the duration of HCV infection (P < 0.05). Laser-evoked potential amplitudes were significantly lower in patients with than in those without neuropathic pain (P < 0.05). Conversely, no difference was found in nerve conduction study and skin biopsy findings (P > 0.05). Our findings show that peripheral neuropathy is related to age and HCV infection, rather than to cryoglobulinemia, and neuropathic pain is associated with damage to nociceptive pathways as assessed with laser-evoked potentials; this might be useful for designing more effective clinical interventions for these common HCV related-cryoglobulinemia complications.


Assuntos
Crioglobulinemia/complicações , Hepatite C/complicações , Doenças do Sistema Nervoso Periférico/patologia , Pele/patologia , Potenciais de Ação , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Crioglobulinemia/etiologia , Feminino , Pé/inervação , Pé/patologia , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Neuralgia/etiologia , Neuralgia/patologia , Exame Neurológico , Neurônios Aferentes/patologia , Doenças do Sistema Nervoso Periférico/fisiopatologia
10.
J Neurol ; 260(3): 761-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23052607

RESUMO

Patients with painful neuropathy frequently complain of pain in response to normally non-painful brushing, namely dynamic mechanical allodynia. Despite many animal studies suggesting that allodynia arises when the spontaneous firing in damaged nociceptive afferents sensitise second-order nociceptive neurons to Aß-fibre input, no studies have sought to confirm this mechanism by investigating Aß-fibre sparing in human patients with allodynia. In this study we compared data from Aß-fibre-mediated nerve conduction studies and nociceptive-fibre-mediated laser-evoked potentials (LEPs) in 200 patients with distal symmetric polyneuropathy (114 with neuropathic pain, 86 without). Of the 114 patients with painful neuropathy studied, 44 suffered from allodynia. Whereas no statistical difference was found in nerve conduction study data between patients with and without allodynia, LEP amplitudes were larger in patients with allodynia than in those without (P < 0.01 by Mann-Whitney U test). The lack of difference in NCS data between patients with and without allodynia suggest that this type of pain, rather than arising through second-order nociceptive neuron sensitization to Aß-fibre input, might reflect a reduced mechanical threshold in sensitised intraepidermal nociceptive nerve terminals.


Assuntos
Potenciais Somatossensoriais Evocados/fisiologia , Hiperalgesia/fisiopatologia , Fibras Nervosas Mielinizadas/fisiologia , Nociceptores/fisiologia , Polineuropatias/fisiopatologia , Humanos , Hiperalgesia/diagnóstico , Hiperalgesia/epidemiologia , Dor/diagnóstico , Dor/epidemiologia , Dor/fisiopatologia , Estimulação Física/métodos , Polineuropatias/diagnóstico , Polineuropatias/epidemiologia , Estudos Prospectivos
13.
Clin Exp Immunol ; 147(2): 270-6, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17223968

RESUMO

Interferons (IFNs) are used widely in the treatment of viral infections, tumours and neurological disorders. The aim of this study was to evaluate the endogenous expressions of various IFN-induced compounds [specifically: neopterin (NPT), beta2microglobulin (beta2mg) and 2-5 oligoadenylate synthetase (2-5 OAS)] in patients with various chronic diseases requiring treatment with IFN type I. The results showed that patients with such chronic diseases as hepatitis C virus-associated type II mixed cryoglobulinaemia (MC), chronic hepatitis C (CHC) and relapsing-remitting multiple sclerosis (RRMS) are characterized by different activations of the IFN system. Furthermore, the interindividual variability in baseline levels of IFN-induced biomarkers was higher in patients with chronic diseases than in healthy individuals. When levels of the above biomarkers were measured 24 h after the first injection of IFN in patients with CHC or RRMS, significant increases in expression levels of IFN-induced compounds were recorded but, again, there is a broad range of variability in the degree of increase. Further, a significant inverse correlation between baseline levels of NPT, beta2mg and 2-5 OAS activity and their relative increases after IFN administration was found in patients with CHC or RRMS. Together, the results are consistent with the observation that there is considerable interindividual heterogeneity in the clinical response to IFNs, which suggests that host factors other than disease markers must be taken into account in order to manage and optimize the IFN therapy.


Assuntos
Doença Crônica/tratamento farmacológico , Interferon Tipo I/imunologia , 2',5'-Oligoadenilato Sintetase/sangue , Adulto , Idoso , Antivirais/uso terapêutico , Biomarcadores/sangue , Crioglobulinemia/tratamento farmacológico , Crioglobulinemia/imunologia , Feminino , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/imunologia , Humanos , Fatores Imunológicos/uso terapêutico , Interferon Tipo I/uso terapêutico , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/imunologia , Neopterina/sangue , Microglobulina beta-2/sangue
14.
Clin Exp Dermatol ; 15(2): 121-3, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2347103

RESUMO

Auto-immune mechanisms, mostly cell mediated, have been described as the basic abnormality in polymyositis and dermatomyositis. We report here the case of a patient affected with dermatopolymyositis, resistant to therapy, who was treated with corticosteroids and cyclosporin. She presented with an infiltrative, erythematous rash on the neck, eyelids and cheeks and weakness of the proximal limb and cervical muscles. The dramatic and persistent response to cyclosporin obtained in this case represents a clear demonstration of the action of this drug in cases of dermatomyositis.


Assuntos
Ciclosporinas/uso terapêutico , Dermatomiosite/tratamento farmacológico , Azatioprina/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade
15.
Blood ; 78(12): 3142-7, 1991 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-1742481

RESUMO

Severe type II essential mixed cryoglobulinemia (EMC) bears a poor prognosis. Treatment with corticosteroids and/or cytotoxic drugs infrequently results in long-term remissions, and is associated with significant toxicity. We conducted a prospective study with interferon (IFN) in 21 patients with severe type II EMC unresponsive to immunosuppressive regimens. They were treated with recombinant IFN-alpha 2a (18 patients) or with natural IFN-beta (three patients), alone, at a dosage of 3 megaunits (MU)/d for 3 months, followed by 3 MU every other day as maintenance. We observed 11 complete remissions, five partial remissions, and five minor responses. Of 16 patients observed for more than 1 year, 11 remained in remission for 14 to 40 months; five of them remained in complete remission for 18 to 40 months after withdrawal of treatment. Four patients discontinued treatment because of side effects. In four patients who relapsed while on maintenance therapy with recombinant IFN-alpha 2a, remission could be reinduced by treatment with natural IFN-alpha. The response rate of 77% achieved in this study prompts the use of IFN-alpha as a first-choice drug for type II EMC.


Assuntos
Crioglobulinemia/terapia , Interferon-alfa/uso terapêutico , Adulto , Idoso , Anticorpos/sangue , Resistência a Medicamentos , Feminino , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes , Recidiva , Indução de Remissão
16.
J Immunol ; 157(8): 3727-36, 1996 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-8871676

RESUMO

Type II mixed cryoglobulinemia (CryoII) is an autoimmune disorder frequently associated to human hepatitis C virus (HCV) infection and characterized by the presence of cold-insoluble immunocomplexes containing IgM with rheumatoid activity. To identify disease-related epitopes, we screened a phage-displayed random peptide library using purified IgM from patients with HCV-associated CryoII(CryoII/HCV). A dominant population of phage isolates bearing the HPLAP pentapeptide consensus motif was identified and shown to be recognized by a nonrheumatoid IgM species strongly associated to CryoII/HCV. The phage-borne mimotopes (phagotopes) displayed a strong homology with an exposed extra-loop region of human lymphocyte activation 3 gene (LAG-3) product. Consistently, rabbit sera raised against a synthetic LAG-3 peptide efficiently recognized the selected phagotopes. Furthermore, one such phagotope was revealed to be a good immunogenic mimic of LAG-3 when injected into rabbits. IgM purified from CryoII/HCV patients' sera specifically reacted with the LAG-3 peptide in ELISA, and this binding was inhibited by the selected phagotopes. These results provide experimental support for a general strategy to identify novel autoantigens.


Assuntos
Antígenos CD , Doenças Autoimunes/complicações , Doenças Autoimunes/imunologia , Antígenos CD4 , Crioglobulinemia/complicações , Crioglobulinemia/imunologia , Hepatite C/complicações , Hepatite C/imunologia , Imunoglobulina M/sangue , Proteínas de Membrana/imunologia , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos , Autoantígenos/genética , Sequência de Bases , Antígenos CD4/genética , Crioglobulinemia/classificação , DNA Complementar/genética , Epitopos/genética , Humanos , Proteínas de Membrana/genética , Dados de Sequência Molecular , Oligopeptídeos/genética , Oligopeptídeos/imunologia , Coelhos , Fator Reumatoide/sangue , Proteína do Gene 3 de Ativação de Linfócitos
17.
J Viral Hepat ; 10(6): 455-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14633180

RESUMO

Mixed cryoglobulinaemia, when not secondary to other well-defined immunological disorders, is commonly associated with hepatitis C virus (HCV) infection. However, a minority of cases lack evidence of HCV infection and are, therefore, defined as 'true essential' mixed cryoglobulinaemias. We thoroughly investigated three such patients to determine the aetiology of this disorder. Antibodies to HCV (anti-HCV) and HCV RNA, detected by sensitive enzyme-linked immunosorbent and polymerase chain reaction assays in serum and in concentrated cryoglobulins, were repeatedly negative in the three patients. Despite the lack of evidence for HCV infection, two of them were still treated with interferon alpha-2a assuming unrecognized viral infection. Both patients demonstrated excellent clinical and laboratory responses, but cryoglobulinaemia relapsed after the withdrawal of therapy. At the time of relapse, HCV RNA genomic sequences were detected for the first time in the cryoprecipitates of both patients. In the third case, HCV RNA was demonstrated for the first time during a flare of cryoglobulinaemia coincident with varicella infection. In all three patients anti-HCV antibodies remained negative throughout follow-up. We conclude that some apparently 'essential' forms of mixed cryoglobulinaemia can be caused by occult HCV infection. Interferon therapy can be taken into consideration in such HCV-negative cases.


Assuntos
Crioglobulinemia/tratamento farmacológico , Crioglobulinemia/etiologia , Hepatite C/complicações , Adulto , Antivirais/farmacologia , Antivirais/uso terapêutico , Feminino , Anticorpos Anti-Hepatite C/sangue , Humanos , Interferon alfa-2 , Interferon-alfa/farmacologia , Interferon-alfa/uso terapêutico , Pessoa de Meia-Idade , RNA Viral/sangue , Proteínas Recombinantes
18.
J Clin Immunol ; 16(6): 321-5, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8946276

RESUMO

The association between an acquired form of hyper-IgM syndrome and a chronic hepatitis C virus (HCV) infection in a 71-year-old female patient is described. Both diseases were diagnosed at the age of 58 years. She was started on intramuscular and then intravenous immunoglobulin replacement therapy. HCV RNA was detected in 1992. The patient remained in well-balanced clinical condition until 1994, when total and specific anti-HCV IgM levels increased and the patient developed an IgM kappa monoclonal gammopathy. Adherent cells and B cells were HCV RNA positive, while T cells were HCV RNA negative. Anti-IgM reactivity was specifically directed to the core antigen of the HCV. The patient we describe showed a picture of a late-onset form of hypogammaglobulinemia with a progressive increase in IgM antibodies, possibly due to the concomitant HCV infection. It is possible that the immunodeficiency might also result from the HCV infection, with formation of specific antibodies belonging to the IgM class, and that the worsening of the clinical condition may be directly related to the persistent viral infection.


Assuntos
Hepatite C/complicações , Hipergamaglobulinemia/complicações , Imunoglobulina M , Idoso , Anticorpos Antivirais/análise , Doença Crônica , Disgamaglobulinemia/complicações , Disgamaglobulinemia/terapia , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/imunologia , Humanos , Hipergamaglobulinemia/imunologia , Deficiência de IgG/complicações , Deficiência de IgG/terapia , Imunoglobulina M/imunologia , Imunoglobulinas Intravenosas/uso terapêutico , Subpopulações de Linfócitos/imunologia , Reação em Cadeia da Polimerase , RNA Viral/análise , Síndrome
19.
Blood ; 90(10): 3865-73, 1997 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9354653

RESUMO

We have prospectively studied patients with type II cryoglobulinemia since 1985 to assess the efficacy of treatment with interferon-alpha at cumulative doses ranging from 234 to 849 MU. In the present study we retrospectively evaluated in this cohort parameters associated with complete response to therapy in 31 consecutive patients with type II cryoglobulinemia associated with hepatitis C virus (HCV) infection. Prevalence of complete response of cryoglobulinemia (disappearance of symptoms and signs of vasculitis and decrease of cryocrit below 10% of the initial value) was 62%, with a median response duration of 33 months and a range of 3 to 100 months. Three patients were putatively cured, as they remained in complete remission for more than 5 years off therapy. Eighteen patients (58%) had liver disease evidenced by histopathology and/or raised transaminase levels. Prevalence of normalization of transaminase levels was 100%, with a median response duration of 36 months. Relapse of hypertransaminasemia occurred in 100% and 8% of patients receiving less than or greater than 621 MU, respectively. By logistic regression analysis, the only pretherapy parameter that associated significantly (P = .0393) with complete response of cryoglobulinemia was the solitary anti-C22 (HCV core) antibody pattern, which was observed in 29% of patients. Association with older age and low cryocrit approached statistical significance (P = . 06), while no significant correlations were found with serum IgM levels, duration of disease, HCV genotype, NS5a gene mutations, liver histology, HLA-DR phenotype, or WA cross-idiotype. Complete responses were also associated, on univariate statistical analysis, with low pretherapy HCV viremia. Responses were accompanied by decrease of viremia, of anti-HCV antibody levels and cryocrit. The usefulness of a high dose regimen is underscored by the higher rates of sustained responses of cryoglobulinemia and transaminase levels compared with previous studies.


Assuntos
Crioglobulinemia/tratamento farmacológico , Hepatite C/complicações , Interferon-alfa/administração & dosagem , Adulto , Idoso , Crioglobulinemia/complicações , Crioglobulinemia/fisiopatologia , Feminino , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Fatores de Tempo , Resultado do Tratamento
20.
Arthritis Rheum ; 42(9): 2007-11, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10513819

RESUMO

We describe a case of type II mixed cryoglobulinemia, with monoclonal IgMkappa rheumatoid factor, associated with visceral leishmaniasis caused by Leishmania infantum. Involvement of Leishmania antigen(s) in the formation of cryoprecipitable immune complexes was suggested by the fact that cryoglobulinemic vasculitis subsided after antiparasite therapy and that anti-Leishmania antibodies, as well as rheumatoid factor, were enriched in the cryoprecipitate. We observed 2 additional patients with visceral leishmaniasis and cryoglobulinemic vasculitis. All 3 patients had seemingly contracted leishmaniasis in Italy, were hepatitis C virus negative, and were initially diagnosed as having autoimmune disorders. These findings indicate that Leishmania can be an etiologic agent of type II mixed cryoglobulinemia. This parasitosis should be taken into consideration in the differential diagnosis of vasculitides in endemic areas.


Assuntos
Crioglobulinemia/complicações , Leishmaniose Visceral/etiologia , Adulto , Animais , Antígenos de Protozoários/sangue , Crioglobulinemia/sangue , Crioglobulinemia/imunologia , Humanos , Leishmania/imunologia , Masculino , Vasculite/diagnóstico
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