RESUMO
Haplotypes and subhaplotypes in the beta-globin gene cluster were identified in 146 and 156 chromosomes, respectively, of three tribes of Colombian Amerinds. Subhaplotype [+----] was a major one in Colombian Amerinds as in most human ethnic groups except Africans. A major subhaplotype [----+] in Africans was observed in only one chromosome. The framework 2 frequencies were very low (0.018-0.067). Haplotype [+----++], which is a major one in Europeans, but not in Asians, and [+-----+], which is a major one in Asians, but not in Europeans, were two major haplotypes. Subhaplotype data showed the closest genetic affinities between Colombian Amerinds and Polynesians, Micronesians, and Asians, but the haplotype data did not necessarily support this.
Assuntos
Globinas/genética , Haplótipos , Indígenas Sul-Americanos/genética , Colômbia , Humanos , Polimorfismo GenéticoRESUMO
Very-long-chain acyl-coenzyme A dehydrogenase (VLCAD) deficiency is a disorder of fatty acid beta oxidation that reportedly has high rates of morbidity and mortality. We describe the outcome of a 5-year-old girl with VLCAD deficiency who was first seen at 5 months of age with severe hypertrophic cardiomyopathy, hepatomegaly, encephalopathy, and hypotonia. Biochemical studies indicated VLCAD deficiency caused by a stable yet inactive enzyme. Molecular genetic analysis of her VLCAD gene revealed a T1372C (F458L) missense mutation and a 1668 ACAG 1669 splice site mutation. After initial treatment with intravenous glucose and carnitine, the patient has thrived on a low-fat diet supplemented with medium-chain triglyceride oil and carnitine and avoidance of fasting. Her ventricular hypertrophy resolved significantly over 1 year, and cognitively, she is in the superior range for age. Clinical recognition of VLCAD deficiency is important because it is one of the few directly treatable causes of cardiomyopathy in children.
Assuntos
Cardiomiopatia Hipertrófica/etiologia , Ácidos Graxos Dessaturases/deficiência , Erros Inatos do Metabolismo/genética , Erros Inatos do Metabolismo/terapia , Acil-CoA Desidrogenase de Cadeia Longa , Cardiomiopatia Hipertrófica/metabolismo , Cardiomiopatia Hipertrófica/terapia , Pré-Escolar , Análise Mutacional de DNA , Feminino , Humanos , Erros Inatos do Metabolismo/complicações , Erros Inatos do Metabolismo/dietoterapia , Mutação , Testes Neuropsicológicos , Resultado do TratamentoRESUMO
The epidermal blistering disease, pemphigus vulgaris (PV), is caused by circulating autoantibodies that react with a desmosomal glycoprotein desmoglein (Dsg3). This antigen is expressed only in stratified epithelial tissues. Here we show that the simple epithelial canine kidney cell line, MDCK, expresses at least two desmoglein isoforms recognised by different monoclonal antibodies. One of these isoforms is a 130 x 10(3) M(r) polypeptide that is recognised by both PV autoantisera and a monoclonal antibody reactive with a cytoplasmic domain of human Dsg3. Antibodies in PV sera bind to the surface of MDCK cells but not cause loss of intercellular adhesion. This is the first demonstration of the expression of a polypeptide related to human PV antigen by a simple epithelial cell type.
Assuntos
Caderinas/análise , Proteínas do Citoesqueleto/análise , Animais , Anticorpos Monoclonais , Western Blotting , Caderinas/imunologia , Bovinos , Adesão Celular , Moléculas de Adesão Celular/análise , Linhagem Celular , Proteínas do Citoesqueleto/imunologia , Desmogleína 3 , Desmogleínas , Desmoplaquinas , Cães , Eletroforese em Gel de Poliacrilamida , Epiderme/ultraestrutura , Epitélio , Imunofluorescência , Humanos , Rim , Microscopia Imunoeletrônica , Peso Molecular , Pênfigo/imunologiaRESUMO
The ultrastructural localization of Brazilian pemphigus foliaceus (BPF) (fogo selvagem) antigen(s) in cultured human squamous cell carcinoma cells was studied using immunogold electron microscopy. Five of six BPF sera, which showed positive cell-surface reactivity on immunofluorescence, bound to the cell-cell contact area of cytoplasmic projections. This binding pattern was apparently different from that of non-endemic pemphigus foliaceus and pemphigus vulgaris sera, and mouse monoclonal anti-human E-cadherin antibody. The results suggest that BPF autoantibodies recognize a molecule(s) which is different from non-endemic pemphigus antigens, or different epitope(s) of a molecule identical with non-endemic pemphigus antigens, and that the epitope(s) to which BPF autoantibodies bind is expressed on cell-cell contact areas at a relatively early stage of cell-cell adhesion formation.
Assuntos
Autoantígenos/análise , Carcinoma de Células Escamosas/imunologia , Pênfigo/imunologia , Sítios de Ligação de Anticorpos , Carcinoma de Células Escamosas/ultraestrutura , Moléculas de Adesão Celular/análise , Epitopos/análise , Humanos , Masculino , Microscopia Eletrônica , Neoplasias Penianas/imunologia , Células Tumorais Cultivadas/imunologiaRESUMO
Recently, it has been shown that desmoglein, pemphigus foliaceus target antigen, and a 130-kD pemphigus vulgaris antigen belong to the cadherin family of cell adhesion molecules. We tried to determine whether desmocollins I/II, other cadherin-like transmembranous glycoproteins present in desmosomes, are also recognized by pemphigus autoantibodies of the IgG class. We examined 16 pemphigus vulgaris sera, 15 pemphigus foliaceus sera, 15 Brazilian pemphigus foliaceus sera, five bullous pemphigoid sera, and 65 normal sera. Four (25%) pemphigus vulgaris sera, one (7%) pemphigus foliaceus serum, eight (53%) Brazilian pemphigus foliaceus sera, and three (5%) normal sera reacted with desmocollins I/II on immunoblots of bovine desmosome preparation. The affinity-purified desmocollins I/II pemphigus autoantibodies were shown to bind the epidermal cell surface by indirect immunofluorescence. Immunoblot analysis revealed one pemphigus vulgaris serum, one Brazilian pemphigus foliaceus serum, and one normal serum recognizing a recombinant protein produced by a desmocollin cDNA clone. Moreover, immunoblot analysis of reactivity of a Brazilian pemphigus foliaceus serum with recombinant proteins produced by deletion mutants of the desmocollin cDNA clone showed that the extracellular portion of desmocollin is immunogenic in this pemphigus patient. We conclude that desmocollins I/II are recognized by certain sera from patients with various types of pemphigus, particularly Brazilian pemphigus foliaceus. However, the significance of this reactivity remains to be defined.
Assuntos
Proteínas do Citoesqueleto/sangue , Pênfigo/sangue , Animais , Anticorpos/sangue , Antígenos/análise , Bovinos , Cromatografia de Afinidade , Proteínas do Citoesqueleto/análise , Desmocolinas , Desmogleínas , Desmoplaquinas , Desmossomos/química , Desmossomos/imunologia , Epiderme/imunologia , Humanos , Immunoblotting , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina G/isolamento & purificação , Pênfigo/imunologia , Proteínas Recombinantes/análise , Proteínas Recombinantes/sangueRESUMO
We investigated the Brazilian pemphigus foliaceus (BPf) antigen applying the immunoblotting method to two different antigen sources using 27 patients' sera. Twelve BPf sera reacted specifically with a 150 kD protein in extract of dispase separated human epidermis, while 18 sera yielded a similar protein band in bovine muzzle desmosomal preparation. The diversity of staining intensities between the two samples suggested the heterogeneity of BPf antigens in terms of epitopes. Japanese sporadic pemphigus foliaceus (Pf) sera showed similar results but Japanese pemphigus vulgaris (Pv) sera recognized different antigens of 130 kD or 135 kD, suggesting that BPf is similar to Japanese Pf but is distinct from Pv in respect to the antigenic substance. Furthermore, the present study showed that immunoblot analysis using different antigen sources should be a valuable tool to determine clinical types of pemphigus.
Assuntos
Antígenos/imunologia , Pênfigo/imunologia , Animais , Brasil , Bovinos , Extratos Celulares/análise , Extratos Celulares/imunologia , Desmossomos/análise , Desmossomos/imunologia , Ácido Edético , Eletroforese em Gel de Poliacrilamida , Células Epidérmicas , Epiderme/análise , Epiderme/imunologia , Epitopos/imunologia , Humanos , Soros Imunes/imunologia , Immunoblotting , Japão , Pênfigo/diagnósticoRESUMO
Human IgG possesses four main subclasses, namely IgG1, IgG2, IgG3, and IgG4, of these IgG1-IgG3 fix complement, but IgG4 does not. We have studied the IgG subclasses of intercellular antibodies in the sera from 20 patients with Brazilian pemphigus foliaceus by immunofluorescent staining using mouse monoclonal antibodies against human IgG1-IgG4. At the same time, the complement fixing capability of each antibody was examined by complement immunofluorescence. All of four subclasses were frequently detected in most cases with varying distributions. However, no specific pattern was observed. Complement fixing antibodies were found in four patients. However, the distribution of IgG subclasses was incompatible with their known characteristics in terms of complement activation. This discrepancy increases the controversy over the importance of the complement system in blister formation in pemphigus.
Assuntos
Imunoglobulina G/classificação , Pênfigo/imunologia , Brasil , Testes de Fixação de Complemento , Imunofluorescência , Humanos , Imunoglobulina G/análiseRESUMO
A male infant with typical clinical and biochemical findings of Zellweger syndrome, but in whom hepatic peroxisomes were detected by electron microscopy, had profound hypotonia, hepatomegaly, typical facial appearance including large fontanelle and frontal bossing, convulsions, panaminoaciduria, and hyperammonemia. He died of liver failure at age 5 months. There were increased levels of very long chain fatty acids and trihydroxycoprostanic acid in serum, and increased excretion of dicarboxylic acids and tyrosine metabolites in the urine. Levels of peroxisomal enzymes, acyl coenzyme A oxidase, bifunctional protein, 3-ketoacyl coenzyme A thiolase, and dihydroxyacetone phosphate acyltransferase in the liver tissue from the patient were all deficient, findings consistent with Zellweger syndrome. However, immunocytochemical study and electron microscopic examination of the liver at autopsy revealed that hepatic peroxisomes were present at a level similar to that in a control subject. These observations suggest further heterogeneity in Zellweger syndrome and a different pathogenesis in this variant case.