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1.
J Eur Acad Dermatol Venereol ; 28(4): 491-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23461376

RESUMO

BACKGROUND: Polymorphisms of genes controlling cytokine production have not been studied in the genetic susceptibility to cutaneous adverse drug reactions (CADR). OBJECTIVES: The objective was to determine whether polymorphisms in nine cytokine genes were associated to the occurrence of drug reaction with eosinophilia and systemic symptoms (DRESS) compared to drug-induced maculopapular eruption or urticaria and to controls without drug intolerance. METHODS: Results from 118 patients with a well-defined CADR were compared to 236 controls without drug intolerance living in the same area of France. We assessed nine polymorphisms: interleukin (IL)1-alpha-889C>T (rs 1800587), IL1-beta-511C>T (rs 16944), IL1-RN intron-2-VNTR (rs2234663), IL2-330T>G (rs 2069762), IL4-33C>T (rs 2070874), IL5-745C>T (rs 2069812), IL10-592C>A (rs 1800872), IL16-295T>C (rs 4778889) and tumour necrosis factor-alpha-308G>A (rs 1800629). RESULTS: Three polymorphisms exhibited a significant association with CADR (P < 0.05). The combination of the IL1-RN-A2 and IL1-beta-511C alleles was statistically different between cases and controls (P = 0.007) and the A2C haplotype was associated with susceptibility to CADR, particularly in drug reaction with eosinophilia and systemic symptoms (DRESS) patients (odds ratio = 3.22; 95% confidence interval = 1.23-8.41; P = 0.016). The frequency of the IL10-592A allele was higher in DRESS patients than in controls (dominant model CC vs. CA + AA: P = 0.035). These abnormalities were not evident in maculopapular eruptions or urticaria. CONCLUSIONS: This is the first study showing that IL1-cluster polymorphisms and haplotypes and the IL10-592A allele (a low IL10 producer) are associated with DRESS. These gene variants may decrease drug tolerance and promote herpes virus reactivation.


Assuntos
Citocinas/genética , Síndrome de Hipersensibilidade a Medicamentos/genética , Eosinofilia/induzido quimicamente , Polimorfismo Genético , Idoso , Estudos de Casos e Controles , Eosinofilia/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
Allergy ; 68(8): 1076-80, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23888881

RESUMO

BACKGROUND: Polymorphisms of interleukin genes related to IgE production and inflammation are predictors of hypersensitivity to betalactam, but nothing is known on the influence of NOD genes, despite their association with inflammation and atopy. OBJECTIVE: To evaluate the association of NOD2 and NOD1 polymorphisms with betalactam allergy. METHOD: We genotyped 3 polymorphisms of NOD2 and 1 of NOD1 in 368 Italian and 387 Spanish patients, compared with 368 and 326 controls, respectively. RESULTS: CT/TT genotypes of rs2066845 of NOD2 predicted a lower risk in Italy (P = 0.003), while WT/insC genotype of rs5743293 (also in leucine-rich repeat domain) predicted a higher risk in Spain (P = 0.007). G allele of rs2066845 was associated with a higher level of IgE in the Italian population. CONCLUSION: The mirrored influence of these NOD2 polymorphisms on betalactam allergy in two populations suggests a link with pathways of inflammation and/or atopy through mechanisms, which need to be clarified.


Assuntos
Alérgenos/genética , Alérgenos/imunologia , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD2/genética , Polimorfismo Genético/imunologia , beta-Lactamas/imunologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Hipersensibilidade/genética , Hipersensibilidade/imunologia , Hipersensibilidade/patologia , Imunoglobulina E/biossíntese , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem , beta-Lactamas/efeitos adversos
3.
Ann Dermatol Venereol ; 139(1): 15-22, 2012 Jan.
Artigo em Francês | MEDLINE | ID: mdl-22225738

RESUMO

BACKGROUND: An association between herpes virus reactivations and Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) is accepted. We report six cases of DRESS with viral reactivation occurring within a single 1-month period. We attempted to find a common factor for these six cases and carried out clinical and virological examinations. Before and after this "epidemic", the mean number of cases of DRESS seen at the same centre was one per quarter, making the occurrence of six cases within a single month all the more remarkable and prompting us to seek an explanation. PATIENTS AND METHODS: All six patients had taken a partly causative medication from different drug classes three to six weeks prior to the start of symptoms and herpes virus was detected in the blood of all of these subjects at the time of DRESS onset (four reactivations and two primary infections), and one patient subsequently displayed herpetic meningoencephalitis 95 days after the initial episode, associated with recurrence of DRESS. DISCUSSION: There was no common denominator among these six DRESS patients in terms of either drug class or reactivation of a particular type of herpes virus, which raises the possibility of a single unidentified environmental agent. DRESS does not appear fully explainable in terms of a cellular response to drug antigens but seems rather to result from complex interactions between the drug-induced immune response, viral reactivation and antiviral immune response. Several investigators have reported sequential reactivation of herpes viruses in DRESS. A viral epidemic could thus cause a "DRESS epidemic" in patients on medication. CONCLUSION: These cases point to the possible existence of a shared initial environmental factor (infectious or not) that favours reactivation of herpes viruses and induces DRESS in patients on medication. Before and after this "DRESS epidemic", about one patient each quarter was admitted to hospital for DRESS.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Surtos de Doenças , Toxidermias/epidemiologia , Infecções por Vírus Epstein-Barr/epidemiologia , Síndrome Hipereosinofílica/epidemiologia , Infecções por Roseolovirus/epidemiologia , Estações do Ano , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Adulto , Idoso , Alopurinol/efeitos adversos , Amoxicilina/efeitos adversos , Antibacterianos/efeitos adversos , Carbamazepina/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/epidemiologia , Toxidermias/etiologia , Infecções por Vírus Epstein-Barr/complicações , Feminino , França/epidemiologia , Herpesvirus Humano 4/fisiologia , Herpesvirus Humano 6/fisiologia , Herpesvirus Humano 7/fisiologia , Humanos , Síndrome Hipereosinofílica/induzido quimicamente , Síndrome Hipereosinofílica/etiologia , Imidazóis/efeitos adversos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Infecções por Roseolovirus/complicações , Combinação Trimetoprima e Sulfametoxazol/efeitos adversos , Ativação Viral
4.
Ann Dermatol Venereol ; 139(5): 375-80, 2012 May.
Artigo em Francês | MEDLINE | ID: mdl-22578342

RESUMO

BACKGROUND: Multiple-drug hypersensitivity (MDH) in the literature concerns different entities. Our objective was to define its frequency and characteristics in patients examined for cutaneous adverse drug reaction (CADR) before studying genetic predisposition. MATERIALS AND METHODS: From a database comprising all patients referred for CADR between 2000 and 2010, we selected those meeting the following criteria: sensitisation to at least two chemically unrelated substances, as confirmed by positive skin tests or challenge tests. The following were excluded: patients with haematological diseases, HIV or chronic wounds and sensitization to the excipients. RESULTS: Of the 1925 patients included, 11 (0.6%) were classed as polysensitized: eight women and three men, of mean age 62 years, presenting 2.5 episodes of drug hypersensitivity per patient. Four cases of DRESS were noted. DISCUSSION: The strict criteria stipulated for this study enabled us to select patients with MDH, and to affirm that while it does in fact exist, it seems rare. Compared to polysensitized patients described in the literature, we preferred to distinguish between three groups of MDH: one occurring with different substances in separate episodes of CADR, one occurring with different substances during the same episode of CADR, and one occurring during DRESS and correlating with viral replication. CONCLUSION: MDH exists and genetic predisposition could be investigated by studying cytokine polymorphism in such patients. However, because of its rarity, it is impossible to rule out fortuitous association of two episodes of CADR in the same patient.


Assuntos
Toxidermias , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Adulto , Idoso , Toxidermias/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Clin Exp Allergy ; 41(5): 657-64, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21375605

RESUMO

BACKGROUND: Delayed reactions to iodine contrast media (CM) account for 1-3% of patients with adverse reactions to iodine CM. The cellular and molecular mechanisms of these reactions remain poorly documented. Although most of these reactions are T cell mediated, the involvement of dendritic cells (DC) has not been investigated sufficiently. OBJECTIVE: To determine whether the T cell response to iodixanol requires DC as antigen-presenting cell and, more particularly, to evaluate the changes induced by iodixanol on DC maturation and in vitro production of cytokines after drug stimulation in patients with maculopapular exanthema. METHODS: Peripheral blood lymphocytes, immature monocyte-derived DC (imDC) and skin biopsies were obtained from patients with delayed reactions to iodixanol and tolerant subjects. We studied the consequences of the interaction between DC, lymphocytes and iodixanol by phenotype analysis, proliferation and cytokine production. RESULTS: A T-cell-mediated reaction was evidenced in patient biopsies, with a lymphocyte-rich, peri-vascular infiltrate. Iodixanol induced maturation of imDC from patients but not from controls, with expression of the co-stimulatory markers CD83, CD86 and CD40 and an increase in mean fluorescence intensity of CD80, CD86 and HLA-DR. In the absence of DC, positive cell proliferation to iodixanol was detected in only one patient while the addition of DC produced a positive test in five of the six patients. Similarly, the increase in cytokines (IFN-γ, IL-2, IL-6, IL-1b and TNF-α) was higher when imDC were introduced into the culture together with the culprit drug. CONCLUSION AND CLINICAL RELEVANCE: These results provide evidence for a DC-mediated mechanism in delayed allergic reactions to CM, influencing T cell proliferation and cytokine production. These new insights will be helpful for designing immunotherapeutic strategies and in vitro diagnostic tests of CM-delayed reactions.


Assuntos
Meios de Contraste/efeitos adversos , Células Dendríticas/imunologia , Hipersensibilidade Tardia/imunologia , Ácidos Tri-Iodobenzoicos/imunologia , Idoso de 80 Anos ou mais , Proliferação de Células/efeitos dos fármacos , Citocinas/biossíntese , Citocinas/imunologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/patologia , Humanos , Hipersensibilidade Tardia/diagnóstico , Compostos de Iodo/efeitos adversos , Compostos de Iodo/imunologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Testes Cutâneos , Ácidos Tri-Iodobenzoicos/administração & dosagem
6.
Rev Mal Respir ; 33(7): 612-7, 2016 Sep.
Artigo em Francês | MEDLINE | ID: mdl-26604020

RESUMO

INTRODUCTION: Alpha-1 antitrypsin deficiency is a hereditary disease defined at the biological level by a serum alpha-1 antitrypsin level below 11µM/L. The null variants are characterized by undetectable circulating alpha-1 antitrypsin levels. Suspicion of a null variant requires the use of appropriate diagnostic techniques. CASE REPORT: We report the case of a 33-year old patient presenting with dyspnea on exertion, associated with a moderate airflow obstruction, incompletely reversible. His tobacco use was less than 3pack-years. The thoracic CT-scan showed emphysema. The serum alpha-1 antitrypsin level was collapsed. Phenotyping by isoelectrofocusing on agarose gels did not show any band. The study of the SERPINA1 gene, by PCR-sequence of the II, III, IV and V exons and the flanking intronic sequences, allowed identification of the NullQ0ourém allele in homozygous state. This mutation was found in heterozygous state in both parents of the index case and in one of his brothers. The index case showed a rapid aggravation of the airflow obstruction. CONCLUSION: In the case of a serum alpha-1 antitrypsin deficiency, the analysis of the phenotype of the protein by isoelectrofocusing must be performed as a first-line investigation. The detection of an atypical profile may suggest the presence of deficient alleles other than the PI S and PI Z alleles that can only be characterized by sequencing of the whole SERPINA1 gene. The patients carrying a null mutation have a high risk of severe chronic obstructive pulmonary disease.


Assuntos
Códon sem Sentido , Deficiência de alfa 1-Antitripsina/genética , alfa 1-Antitripsina/genética , Adulto , Dispneia/genética , Humanos , Masculino , Fenótipo , Deficiência de alfa 1-Antitripsina/patologia
7.
Am J Cardiol ; 88(2): 185-8, A6, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11448422

RESUMO

We observed a release of histamine, but not of tryptase, in arterial blood from 64 patients with ischemic heart disease and 24 patients without coronary disease, which was provoked by ioxaglate, a ionic compound, but was not provoked by iomeprol, a non-ionic radiocontrast compound. The release of histamine in arterial blood after ionic contrast medium injection was higher in patients with ischemic heart disease compared with patients without coronary disease, suggesting that an increased release from heart mast cells previously observed exists also for systemic blood basophils.


Assuntos
Meios de Contraste/farmacologia , Angiografia Coronária , Mediadores da Inflamação/metabolismo , Iopamidol/análogos & derivados , Ácido Ioxáglico , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/imunologia , Serina Endopeptidases/metabolismo , Basófilos/imunologia , Estudos de Casos e Controles , Feminino , Liberação de Histamina/efeitos dos fármacos , Humanos , Iopamidol/imunologia , Ácido Ioxáglico/imunologia , Masculino , Mastócitos/imunologia , Pessoa de Meia-Idade , Estudos Prospectivos , Triptases
11.
Immunol Allergy Clin North Am ; 29(3): 429-51, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19563990
12.
Curr Pharm Des ; 14(27): 2770-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18991696

RESUMO

Drug allergy refers to a hypersensitivity reaction for which either an IgE or T-cell-mediated mechanism is demonstrated. The recognition of the drug by B and T cells is influenced by variants of HLA genes. The genetic factors involved in IgE-mediated mechanisms have been studied mainly in beta-lactam reactions, and they appear to be related to human leukocyte antigen presentation (HLA A2 and DRw52), TNFA -308G>A, class switching to IgE by B cells (variants of IL-13 and of IL-4RA), and expression of IgE receptors on target cells (variant of the FcepsilonRIbeta gene). Delayed T-cell-mediated reactions are also associated with HLA alleles. Studies have reported an association of HLA-B*1502 and HLA-B*5801 in patients with the Stevens-Johnson syndrome or toxic epidermal necrolysis provoked by carbamazepine, as well as of HLA-B*5701 with abacavir hypersensitivity. HLA-B*5701 seems to be a strong predictor in whites, but not in Hispanics or Africans. Carbamazepine hypersensitivity is also influenced by gene variants of cytochrome P450 enzymes on the generation of reactive metabolites, while CYP2C9*2 and CYP2C9*3 polymorphisms influence the bioactivation of sulfamethoxazole in prohapten. Pharmacogenetic studies on aspirin hypersensitivity have identified distinct types of predictors, such as HLA genotypes, a polymorphism in the promoter of the FcepsilonRIalpha gene, and variants in genes of enzymes from the arachidonic acid pathway. In the future, identification of genetic predictors will benefit from genomewide association studies that also take ethnic differences into account. Ideally, predictors will help to prevent adverse reactions, as suggested by a recent study on the effectiveness of prospective HLA-B*5701 screening to prevent hypersensitivity reactions to abacavir in HIV patients.


Assuntos
Hipersensibilidade a Drogas/genética , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Hipersensibilidade Tardia/genética , Hipersensibilidade Imediata/genética , Farmacogenética/métodos , Animais , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/imunologia , Humanos , Hipersensibilidade Tardia/diagnóstico , Hipersensibilidade Tardia/imunologia , Hipersensibilidade Imediata/diagnóstico , Hipersensibilidade Imediata/imunologia
13.
Curr Pharm Des ; 14(27): 2809-25, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18991700

RESUMO

Neuromuscular blocking agents are the leading drugs responsible for immediate hypersensitivity reactions during anaesthesia. Most hypersensitivity reactions represent IgE-mediated allergic reactions. Their incidence is estimated to be between 1 in 3,000 to 1 in 110,000 general anaesthetics. However striking variations have been reported among countries. The mechanism of sensitisation seems to implicate the presence of a substituted ammonium ion in the molecule. Due to lack of exposure prior to the reaction in a large number of reactors, it has been hypothesised that sensitisation may involve other, as yet undefined, substituted (quaternary and tertiary) ammonium ion containing compounds such as pholcodine, present in the environment of the patient. This hypothesis is still under investigation. The mechanism of non-IgE mediated hypersensitivity reactions is less well known. Identified mechanisms correspond to direct histamine release or interactions with muscarinic and nicotinic receptors. Allergic reactions cannot be clinically distinguished from non-IgE-mediated reactions. Therefore, any suspected hypersensitivity reaction must be investigated using combined pre and postoperative testing. Because of the frequent but not systematic cross-reactivity observed with muscle relaxants, every available neuromuscular blocking agent should be tested, using intradermal tests to confirm the responsibility of the suspected drug which should be definitely excluded. Cross-sensitivity investigation will also try to identify the safety of drugs that can be potentially used in future anaesthesia. The determination of basophil activation investigations using direct leukocyte histamine release test or flow cytometry would be of particular interest to investigate cross sensitisation in complement to skin tests. There is no demonstrated evidence supporting systematic pre-operative screening in the general population at this time. However, since no specific treatment has been shown to reliably prevent anaphylaxis, allergy assessment must be performed in all high-risk patients. In view of the relative complexity of allergy investigation, and of the differences between countries, an active policy to identify patients at risk and to provide any necessary support from expert advice to anaesthetists and allergologists through the constitution of allergo-anaesthesia centres in every country should be promoted.


Assuntos
Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/prevenção & controle , Bloqueadores Neuromusculares/efeitos adversos , Anafilaxia/diagnóstico , Anafilaxia/etiologia , Anafilaxia/prevenção & controle , Animais , Hipersensibilidade a Drogas/etiologia , Humanos , Fatores de Risco , Testes Cutâneos/métodos
14.
Ann Fr Anesth Reanim ; 30(3): 294-304, 2011 Mar.
Artigo em Francês | MEDLINE | ID: mdl-21392931
16.
J Chromatogr B Biomed Appl ; 664(1): 253-9, 1995 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-7757233

RESUMO

We have identified a soluble receptor for intrinsic factor (IF) in human urine. The purification of this protein by affinity chromatography required a preliminary purification of IF from hog pyloric mucosal extract. This was achieved by thermolabile cobalamin-ethanol-aminohexane Sepharose affinity chromatography with a 133-fold purification, a yield of 45% and a specific binding activity of 15720 pmol/mg protein. The purified Cbl-IF complex was coupled to epoxy-Sepharose with a yield of 23.8% and a specific activity of 1.2 nmol per mol of gel. The soluble IF receptor was purified form 200 ml of urine concentrate of pregnant women. Desorption was performed at pH 5.0 and in the presence of 5 mM EDTA. The soluble IF receptor was purified 17,200-fold with a yield of 52% and a IF binding capacity of 3260 pmol per mg of protein. A single protein with a Mr of 70,000 was found in silver-stained SDS-PAGE.


Assuntos
Cromatografia de Afinidade/métodos , Fator Intrínseco/metabolismo , Receptores de Peptídeos/isolamento & purificação , Sefarose/metabolismo , Animais , Feminino , Mucosa Gástrica/metabolismo , Humanos , Fator Intrínseco/isolamento & purificação , Gravidez/urina , Ligação Proteica , Suínos
17.
Eur J Anaesthesiol Suppl ; 11: 55-64, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8557008

RESUMO

The cross-reactivity of rocuronium with other neuromuscular blocking agents (NMBAs) was studied in 31 patients known to be allergic to a muscle relaxant. Tests for diagnosing cross-reactivity were skin tests (prick tests and intradermal tests: IDTs), detection by RAST assay of IgEs against the quaternary ammonium group (QAS-RIA: quaternary ammonium sepharose radio-immuno-assay), QAS-RIA inhibition test to detect IgE specificity, and leucocyte histamine release test (LHRT). Skin tests were performed with rocuronium, suxamethonium, gallamine, vecuronium, pancuronium, atracurium. The threshold for cross-reactivity was 10(-1) with all the NMBAs except for atracurium (10(-2)). The inhibition test and LHRT were performed with rocuronium and the NMBA responsible for the shock. Ten volunteers made up the control group for prick tests, QAS-RIA, LHRT. Cross-reactivity was found in 30 patients out of 31. Rocuronium did not cross-react in 10 patients out of 31. They had negative cutaneous tests and negative LHRTs. In one of the five patients allergic to all the NMBAs available, rocuronium was the only one which did not cross-react. In those 10 patients, rocuronium may be safely used for subsequent anaesthesia. In terms of allergy, rocuronium appeared to be very close to the other steroidal NMBAs.


Assuntos
Androstanóis/imunologia , Hipersensibilidade a Drogas/imunologia , Fármacos Neuromusculares não Despolarizantes/imunologia , Adulto , Idoso , Especificidade de Anticorpos , Reações Cruzadas , Feminino , Liberação de Histamina/efeitos dos fármacos , Humanos , Técnicas In Vitro , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Anafilaxia Cutânea Passiva , Radioimunoensaio , Rocurônio , Testes Cutâneos
18.
Biochem J ; 313 ( Pt 2): 675-81, 1996 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8573109

RESUMO

We have purified a cobalamin-binding protein obtained by papain digestion of pig intestine by cobalamin-AH-Sepharose affinity chromatography, with a purification factor of 17,300, a yield of 63% and a cobalamin-binding activity of 11,260 pmol/mg of protein. The protein contained 3.8% carbohydrate and was O- and N-glycosylated. Its molecular mass was 69 kDa on SDS/PAGE and its isoelectric point was 5.1. It had a binding activity for both [57Co]cobalamin and [57Co]cobalamin-intrinsic factor in native PAGE autoradiography and it inhibited the binding of intrinsic factor to the intact intestinal receptor with an IC50 of 49.31 nmol/l in a radioisotope assay. In conclusion, the purified protein shared a binding activity for both cobalamin and intrinsic factor-cobalamin complexes and could correspond to the extracellular domain of the ileal intrinsic factor receptor.


Assuntos
Mucosa Intestinal/metabolismo , Fator Intrínseco/isolamento & purificação , Proteínas/isolamento & purificação , Vitamina B 12/metabolismo , Animais , Autorradiografia , Cromatografia de Afinidade , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Hidrólise , Íleo/metabolismo , Fator Intrínseco/metabolismo , Cinética , Ligação Proteica , Proteínas/metabolismo , Suínos
19.
J Chromatogr B Biomed Appl ; 664(1): 211-7, 1995 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-7757227

RESUMO

Peanut is one of the most allergenic foods. Detection of specific IgE in the serum of allergic patients requires the purification of allergenic proteins. In the present work, proteins were recovered from peanut kernel after successive treatment in acetone and diethyl ether. The proteins were dissolved in 0.05% TFA and analysed by RP-HPLC with a 0-100% gradient of methanol containing 0.05% TFA. The protein peaks were recovered and tested in SDS-PAGE. Eleven proteins were identified with a M(r) ranging from 13 to 81. Western blotting was performed with sera from allergic patients. Allergenic proteins had a M(r) of 15, 18, 19, 33, 41 and 67. By comparison, a protein fraction from peanut shell contained seven proteins with M(r) ranging from 15 to 81. Only two proteins with M(r) of 18 and 41 were detected in a Western blot. The protein fractions were coupled to epoxy-Sepharose and the gels were used as a solid reactive phase for detection by IgE-RIA of specific IgE from the serum of allergic patients.


Assuntos
Alérgenos/isolamento & purificação , Arachis , Imunoglobulina E/sangue , Proteínas de Plantas/isolamento & purificação , Western Blotting , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/imunologia , Radioimunoensaio
20.
Gastroenterology ; 108(6): 1622-8, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7768365

RESUMO

BACKGROUND/AIMS: The pathogenesis of inherited intestinal cobalamin malabsorption (Gräsbeck-Imerslund disease) remains unknown. The authors studied whether the disease corresponds to a defective expression and/or function of the intrinsic factor-cobalamin receptor in the ileum. METHODS: Intrinsic factor-cobalamin receptor activity was measured using radioisotope assay and gel-filtration exclusion chromatography in ileal biopsy specimens and urine concentrates from 4 patients with Gräsbeck-Imerslund disease and 5 controls. RESULTS: Receptor activity was 164 +/- 13 fmol/mg of protein in control biopsy specimens and < 2.6 fmol/mg protein in specimens from patients. The association constant was estimated to be 3.8 +/- 0.4 (nmol/L)-1 in controls. A dramatic decrease in receptor activity was also observed in urine concentrate from patients with an association constant of 1.9 and 3.3 (nmol/L)-1. Isoelectrofocusing of the cross-linked intrinsic factor-cobalamin receptor complex showed an isoelectric point at 4.8 in a patient as well as in control samples. CONCLUSIONS: It is concluded that Gräsbeck-Imerslund disease is related to decreased intrinsic factor-receptor activity in intestinal mucosa; the receptor assay in urine can be helpful for diagnosis.


Assuntos
Íleo/química , Síndromes de Malabsorção/metabolismo , Receptores de Superfície Celular/análise , Vitamina B 12/metabolismo , Adulto , Pré-Escolar , Feminino , Humanos , Lactente , Masculino
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