RESUMO
OBJECTIVES: This study examined the acute effect of small-sided-game (SSG) and resistance training sequence on neuromuscular, endocrine and mood response over a 24-h (h) period. DESIGN: Repeated measures. METHODS: Fourteen semi-professional soccer players performed SSG-training (4vs4+goalkeepers; 6×7-min, 2-min inter-set recovery) followed by resistance training 2h later (back-squat, Romanian deadlift, barbell-hip-thrust; 4×4 repetitions, 4-min inter-set recovery; 85% 1 rep-max) (SSG+RES), and on a separate week reversed the session order (RES+SSG). Physical demands of SSG's were monitored using global positioning systems (GPS) and ratings of perceived exertion (RPE). Countermovement-jump (CMJ; peak power output; jump height) and brief assessment of mood were collected before (pre), during (0h) and after (+24h) both protocols. Salivary testosterone and cortisol concentrations were obtained at the same time-points but with the inclusion of a measure immediately prior to the second training session (+2h). RESULTS: GPS outputs and RPE were similar between SSG-training during both protocols. Between-protocol comparisons revealed no significant differences at +24h in CMJ performance, mood, and endocrine markers. Testosterone was higher at 0h during RES+SSG in comparison to SSG+RES (moderate-effect; +21.4±26.7pgml-1; p=0.010), yet was similar between protocols by +2h. CONCLUSIONS: The order of SSG and resistance training does not appear to influence the physical demands of SSG's with sufficient recovery between two sessions performed on the same day. Session order did not influence neuromuscular, endocrine or mood responses at +24h, however a favourable testosterone response from the resistance first session may enhance neuromuscular performance in the second session of the day.
Assuntos
Afeto/fisiologia , Desempenho Atlético/fisiologia , Hidrocortisona/metabolismo , Condicionamento Físico Humano/métodos , Treinamento Resistido/métodos , Futebol/fisiologia , Testosterona/metabolismo , Adulto , Sistemas de Informação Geográfica , Voluntários Saudáveis , Humanos , Masculino , Inquéritos e Questionários , Adulto JovemRESUMO
OBJECTIVES: This study profiled the 24h neuromuscular, endocrine and mood responses to a single versus a double training day in soccer players. DESIGN: Repeated measures. METHODS: Twelve semi-professional soccer players performed small-sided-games (SSG's; 4 vs 4+goalkeepers; 6×7-min, 2-min inter-set recovery) with neuromuscular (peak-power output, PPO; jump height, JH), endocrine (salivary testosterone, cortisol), and mood measures collected before (pre) and after (0h, +24h). The following week, the same SSG protocol was performed with an additional lower body strength training session (back-squat, Romanian deadlift, barbell hip thrust; 4×4 repetitions, 4-min inter-set recovery; 85% 1 rep-max) added at 2h after the SSG's. RESULTS: Between-trial comparisons revealed possible to likely small impairments in PPO (2.5±2.2Wkg-1; 90% Confidence Limits: ±2.2Wkg-1), JH (-1.3; ±2.0cm) and mood (4.6; ±6.1AU) in response to the double versus single sessions at +24h. Likely to very likely small favourable responses occurred following the single session for testosterone (-15.2; ±6.1pgml-1), cortisol (0.072; ±0.034ugdl-1) and testosterone/cortisol ratio (-96.6; ±36.7AU) at +24h compared to the double session trial. CONCLUSIONS: These data highlight that performance of two training sessions within a day resulted in possible to very likely small impairments of neuromuscular performance, mood score and endocrine markers at +24h relative to a single training session day. A strategy of alternating high intensity explosive training days containing multiple sessions with days emphasising submaximal technical/tactical activities may be beneficial for those responsible for the design and delivery of soccer training programs.
Assuntos
Afeto , Desempenho Atlético/fisiologia , Hidrocortisona/análise , Futebol/fisiologia , Testosterona/análise , Atletas , Fadiga , Humanos , Masculino , Condicionamento Físico Humano , Saliva/química , Carga de Trabalho , Adulto JovemRESUMO
Cervical cancer is a common and deadly disease, especially in developing countries. We developed and implemented an interactive, tablet-based educational intervention to improve cervical cancer knowledge among women in rural Malawi. Chichewa-speaking adult women in six rural villages participated. Each woman took a pretest, participated in the lesson, and then took a posttest. The lesson included information on cervical cancer symptoms, causes, risk factors, prevention, and treatment. Over the 6-month study period, 243 women participated. Women ranged in age from 18 to 77 years. Only 15 % had education beyond primary school. Nearly half of participants (48 %) had heard of cervical cancer prior to viewing the lesson. For these women, the median number of correct responses on the pretest was 11 out of 20; after the lesson, they had a median of 18 correct responses (p < 0.001). After the intervention, 93 % of women indicated a desire for cervical cancer screening. Despite lack of familiarity with computers (96 %), most women (94 %) found the tablet easy to use. A tablet-based educational program was an effective, feasible, and acceptable strategy to disseminate cervical cancer information to women with low education in rural Malawi. This method may be appropriate to distribute health information about other health topics in low-resource settings.
Assuntos
Computadores de Mão/estatística & dados numéricos , Detecção Precoce de Câncer/métodos , Conhecimentos, Atitudes e Prática em Saúde , Educação de Pacientes como Assunto , Neoplasias do Colo do Útero/prevenção & controle , Adulto , Estudos de Viabilidade , Feminino , Saúde Global , Humanos , Malaui , População RuralRESUMO
Change of direction speed (CODS) is often considered a main determinant of successful performance in many team sports and is routinely measured using field-based tests. However, controversy regarding test selection still exists based upon the reliability and specificity of the tests. The purpose of this study was to determine and compare the reliability, factorial validity, and interrelationships of five frequently used CODS tests (Illinois, L-Run, Pro-Agility, T-test, and 505). Forty-four physical education students (male n = 24; female n = 20; age; 16.7 ± 0.6), who compete within team sports, to varying levels of competition, participated in this study. Three trials for each of the five tests were recorded. All tests had high (intraclass correlation coefficient) test-retest reliability (r = 0.88-0.95) and low typical percentage error (1.95-2.40%). The principle component factor analysis resulted in the extraction of one significant component which explained 89.52% of the total variance. All selected tests were positively and strongly correlated (r = 0.84-0.89). Based upon the results of this study, it was concluded that all tests are highly reliable and valid measures of CODS, with all tests assessing a general athletic ability to change direction. Future research should investigate the factorial validity of the CODS test within homogenous samples.
Assuntos
Teste de Esforço/métodos , Destreza Motora/fisiologia , Movimento/fisiologia , Adolescente , Análise Fatorial , Feminino , Humanos , Masculino , Análise de Componente Principal , Reprodutibilidade dos TestesRESUMO
We evaluated whether use of a short- or longer-term recall period for condom use was superior for assessing risk of acquisition of incident sexually transmitted infection (STI). Female sex workers (n = 1000) in Madagascar took part in a randomized trial comparing counselling strategies for male and female condom promotion. We explored associations between women's self-reported condom use with clients and non-paying partners and incident STI, examining both short-term recall (last sex act) and longer-term recall (over the past month and year). Self-reported condom use was generally not associated with reduced STI risk, whether measured at the last act or over longer time periods; with clients or non-paying partners; and through unadjusted and adjusted modelling. No condom use measure (short versus longer time periods, with one or both partner types) was strongly predictive of STI, suggesting poor validity.
Assuntos
Preservativos Femininos/estatística & dados numéricos , Preservativos/estatística & dados numéricos , Aconselhamento/métodos , Trabalho Sexual , Infecções Sexualmente Transmissíveis/prevenção & controle , Adulto , Feminino , Humanos , Madagáscar/epidemiologia , Masculino , Valor Preditivo dos Testes , Risco , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/etiologia , Fatores de TempoAssuntos
Rim/fisiopatologia , Podócitos/efeitos dos fármacos , Proteinúria/fisiopatologia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Pressão Sanguínea/efeitos dos fármacos , Humanos , Podócitos/fisiologia , Proteinúria/prevenção & controleRESUMO
OBJECTIVES: People in developing countries often seek medical advice for common ailments from pharmacies. As one example, pharmacists routinely diagnose and treat symptomatic sexually transmitted infections (STIs). We aimed to assess the quality of advice provided in Mexico City pharmacies by presenting hypothetical STI related syndromes and recording pharmacy attendants' suggested diagnoses and treatments. METHODS: We interviewed the first available attendant in each of a 5% random sample of Mexico City's pharmacies. We inquired about the training, age, and experience of the attendant and about the typical number of clients coming for treatment of suspected STIs. After considering three hypothetical case studies, attendants recommended diagnoses, treatments, and, sometimes, physician follow up. RESULTS: Most Mexico City "pharmacists" are actually clerks, with trained pharmacists rarely available on the premises. The average pharmacy attendant was 32 years old, with a median of 5 years' experience at that pharmacy, but very limited (if any) training. 62% reported seeing 10 or more clients with genital or vaginal infections per month. Depending on the case study, attendants provided appropriate diagnoses in 0-12% of cases, recommended appropriate treatments in 12-16% of cases, and suggested physician follow up for 26-67% of cases. CONCLUSIONS: In general, surveyed pharmacy personnel were unable to diagnose accurately or offer appropriate treatment advice when presented with classic, common STI symptoms. Given the volume of clients seeking advice from this source, training pharmacy attendants could significantly help to reduce the burden of disease associated with STIs in Mexico City.
Assuntos
Serviços Comunitários de Farmácia/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/diagnóstico , Adolescente , Adulto , Distribuição por Idade , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , México , Pessoa de Meia-Idade , Farmacêuticos , Infecções Sexualmente Transmissíveis/terapiaRESUMO
BACKGROUND: Autoimmunity to kidney antigens causes membranous nephropathy and Goodpasture's disease and very likely is pivotal in many other glomerular diseases. We investigated the potential for central tolerance to the best-characterized kidney autoantigen, the NC1 domain of the alpha3 chain of type IV collagen [alpha3(IV)NC1], which is the target of autoimmune attack in Goodpasture's disease. METHODS: Indirect immunofluorescence on human thymus and polymerase chain reaction (PCR) and Southern blot analysis of cDNA reverse transcribed from RNA extracted from human thymus and kidney. RESULTS: Indirect immunofluorescence on human thymus demonstrated the presence of alpha3(IV)NC1 in all six thymus samples examined. The homologous collagen IV chain, alpha5(IV)NC1, also was detected with a similar intra-thymic distribution. Strikingly, thymic alpha3 and alpha5 localized around and within Hassall's corpuscles in the thymic medulla, which are structures implicated in T cell apoptosis and possibly negative selection. In contrast, alpha1(IV)NC1 localized to the basement membranes of interlobular septa and blood vessels, as is typical of collagen IV chains situated outside the thymus. Reverse transcription-polymerase chain reaction (RT-PCR) confirmed the presence of mRNA encoding alpha3(IV)NC1 and alpha5(IV)NC1 in thymic tissue establishing that the antigens were likely to have been synthesized locally. CONCLUSIONS: The results demonstrate that alpha3(IV)NC1 is expressed in the human thymus, and therefore should be available for induction of alpha3(IV)NC1-specific tolerance. This observation has the important implication that patients' alpha3(IV)NC1-specific, autoreactive T cells are more likely to recognize cryptic epitopes that are not adequately presented by thymic antigen-presenting cells (APC) than the major antigen-derived epitopes generally identified by conventional approaches.
Assuntos
Autoantígenos/análise , Colágeno Tipo IV/análise , Timo/química , Adolescente , Idoso , Autoantígenos/genética , Criança , Pré-Escolar , Colágeno Tipo IV/genética , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Lactente , Reação em Cadeia da Polimerase , RNA Mensageiro/análiseRESUMO
BACKGROUND: Anti-glomerular basement membrane (GBM) antibody disease is an autoantibody-mediated disorder that usually presents as rapidly progressive glomerulonephritis, often with pulmonary hemorrhage (the Goodpasture syndrome). It is reported that patients with severe renal failure do not generally recover renal function. OBJECTIVE: To examine the long-term outcome of severe anti-GBM antibody disease. DESIGN: Retrospective review of patients treated for confirmed anti-GBM antibody disease over 25 years. SETTING: A tertiary referral center in the United Kingdom. PATIENTS: 71 treated patients with anti-GBM antibody disease. INTERVENTION: All patients received plasma exchange, prednisolone, and cyclophosphamide. MEASUREMENTS: Patient and renal survival, renal histology, and antibody levels. RESULTS: Patients who presented with a creatinine concentration less than 500 micromol/L (5.7 mg/dL) (n = 19) had 100% patient survival and 95% renal survival at 1 year and 84% patient survival and 74% renal survival at last follow-up. In patients who presented with a creatinine concentration of 500 micromol/L or more (>/=5.7 mg/dL) (n = 13) but did not require immediate dialysis, patient and renal survival were 83% and 82% at 1 year and 62% and 69% at last follow-up. In patients who presented with dialysis-dependent renal failure (n = 39), patient and renal survival were 65% and 8% at 1 year and 36% and 5% at last follow-up. All patients who required immediate dialysis and had 100% crescents on renal biopsy remained dialysis dependent. CONCLUSIONS: Patients with the Goodpasture syndrome and severe renal failure should be considered for urgent immunosuppression therapy, including plasma exchange, to maximize the chance of renal recovery. Patients needing immediate dialysis are less likely to recover.
Assuntos
Doença Antimembrana Basal Glomerular/terapia , Ciclofosfamida/uso terapêutico , Imunossupressores/uso terapêutico , Troca Plasmática , Prednisolona/uso terapêutico , Adolescente , Adulto , Idoso , Doença Antimembrana Basal Glomerular/sangue , Doença Antimembrana Basal Glomerular/complicações , Doença Antimembrana Basal Glomerular/imunologia , Terapia Combinada , Creatinina/sangue , Feminino , Humanos , Falência Renal Crônica/etiologia , Falência Renal Crônica/cirurgia , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Estatísticas não Paramétricas , Taxa de Sobrevida , Resultado do TratamentoRESUMO
Several adrenoceptor subtypes are expressed in adipocytes, which together exert their influence on adipocyte metabolism. Therefore, we specifically examined the interactive effect of Trp64Arg (beta3) and Glu12/Glu9 (alpha2b) adrenoceptor (AR) polymorphisms on energy metabolism and body composition in healthy women with a wide range of body habitus. We genotyped 909 unrelated women (age 55 +/- 12 [mean +/- SD] years, range 19-87; body weight 88 +/- 22 kg, range 40-167; and BMI 33 +/- 8 kg/m2, range 16-64) for Trp64Arg beta3AR and Glu12/Glu9 alpha2bAR variants. We examined the independent effect of the Glu12/Glu9 alpha2bAR variant on body composition and energy balance, in a large cohort of Caucasian women (n = 909). A second goal was to examine the interaction effect of Glu12/Glu9 alpha2bAR and Trp64Arg beta3AR on the same phenotypes. The obesity-related phenotypes studied were as follows: body weight, BMI, fat mass, visceral fat, fat-free mass, resting metabolic rate (RMR), VO2max, leisure time physical activity, and daily energy intake. Body composition and body fat distribution were measured by dual-energy X-ray absorptiometry and radiographic imagery, VO2max by a treadmill test to exhaustion, and RMR by indirect calorimetry. An analysis of covariance indicated that in the entire cohort, there was no significant difference between Glu12/Glu9 alpha2bAR carriers and control subjects for any of the obesity-related phenotypes that were examined. However, we observed a significant interaction effect of the Trp64Arg and Glu12/Glu9 variants on fat mass (P = 0.009) and percent fat (P = 0.016). Age, height, body weight, BMI, fat-free mass, visceral fat, energy expenditure, respiratory quotient, physical fitness, and energy intake were not different among groups. Collectively, these findings support an interaction effect of the two adrenoceptor variants on body fatness in Caucasian women, although the physiological mechanism by which they exert this effect remains to be determined.
Assuntos
Tecido Adiposo/anatomia & histologia , Polimorfismo Genético/fisiologia , Receptores Adrenérgicos alfa/genética , Receptores Adrenérgicos beta/genética , População Branca/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Composição Corporal/genética , Estudos de Coortes , Metabolismo Energético/genética , Feminino , Frequência do Gene , Genótipo , Heterozigoto , Humanos , Pessoa de Meia-Idade , Obesidade/genética , Fenótipo , Isoformas de Proteínas/genéticaRESUMO
Goodpasture's disease provides an opportunity to analyse molecular mechanisms that may underlie MHC class II associations with autoimmune disease because it is caused by autoimmunity to a defined antigen [the 230 amino acid NC1 domain of the alpha3 chain of type IV collagen (alpha3(IV)NC1)] and has strong HLA class II associations. We compared the alpha3(IV)NC1 peptide binding of class II molecules with strong positive (DR15) and dominant negative (DR7/1) associations using an inhibition binding assay and short synthetic peptides spanning the sequence of alpha3(IV)NC1. DR15 in general bound the peptides with low affinity (three of 23 < 100 nM) compared to DR1 and DR7 (12 and 10 < 100 nM respectively), and no peptide bound DR15 with much higher affinity (>10-fold) than both DR1 and DR7. Thus DR15 molecules are unlikely to increase susceptibility to Goodpasture's disease by presenting a particular alpha3(IV)NC1-derived peptide uniquely well and DR1/7 are unlikely to protect by their inability to present particular peptides. However DR1/7 could protect by capturing alpha3(IV)NC1 peptides and preventing their display bound to DR15; the binding data suggest that all the major (biochemically detectable) alpha3(IV)NC1 peptides presented bound to DR15 by DR15 homozygous antigen-presenting cells (APC) would bind preferentially to DR1/7 in DR15, 1/7 heterozygote APC.
Assuntos
Doença Antimembrana Basal Glomerular/imunologia , Autoantígenos/imunologia , Doenças Autoimunes/imunologia , Colágeno Tipo IV , Colágeno/imunologia , Genes MHC da Classe II , Antígenos HLA-DR/imunologia , Antígeno HLA-DR7/imunologia , Fragmentos de Peptídeos/imunologia , Alelos , Sequência de Aminoácidos , Animais , Doença Antimembrana Basal Glomerular/genética , Autoantígenos/metabolismo , Doenças Autoimunes/genética , Sítios de Ligação , Ligação Competitiva , Colágeno/metabolismo , Epitopos/imunologia , Genes Dominantes , Antígenos HLA-DR/genética , Antígenos HLA-DR/metabolismo , Subtipos Sorológicos de HLA-DR , Antígeno HLA-DR7/genética , Antígeno HLA-DR7/metabolismo , Cadeias HLA-DRB1 , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Hemaglutininas Virais/imunologia , Hemaglutininas Virais/metabolismo , Humanos , Células L , Camundongos , Dados de Sequência Molecular , Proteína Básica da Mielina/imunologia , Proteína Básica da Mielina/metabolismo , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , TransfecçãoRESUMO
We report a case of anti GBM disease that developed in the renal graft of a patient with Alport syndrome. After reaching abnormal values of creatinine, the patient presented with deteriorating renal function three months after a cadaver transplant and the biopsy showed crescent formation, and linear IF deposits. Circulating antibodies against alpha 5 chain of type IV collagen were found and plasmaphereses stabilized the condition for one year until a lung infection led to withdrawal of the immunosuppressive drugs and the patient returned to dialysis. We discuss the possible mechanisms underlying the specificity of the circulating antibodies in this case, which differs from the target characteristic of the idiopathic form of anti GBM disease, the alpha 3 (IV) chain.
Assuntos
Doença Antimembrana Basal Glomerular/etiologia , Transplante de Rim/efeitos adversos , Nefrite Hereditária/cirurgia , Adulto , Doença Antimembrana Basal Glomerular/diagnóstico , Doença Antimembrana Basal Glomerular/terapia , Rejeição de Enxerto , Humanos , Masculino , PlasmafereseRESUMO
Class II molecules are believed to influence immune responses by selectively binding antigen-derived peptides for recognition by T cells. In Goodpasture's (anti-glomerular basement membrane) disease, autoimmunity to the NC1 domain of the alpha3-chain of type IV collagen (alpha3(IV)NC1) is strongly associated with HLA-DR15. We have examined the influence of the peptide binding preferences of DR15 molecules on the selection of alpha3(IV)NC1-derived peptides displayed bound to DR15 molecules on the surface of alpha3(IV)NC1-pulsed DR15-homozygous Epstein-Barr virus-transformed human B cells. The preferences of DR15 molecules were investigated using a panel of 24 overlapping peptides spanning the sequence of alpha3(IV)NC1. The alpha3(IV)NC1-derived peptides selected for display to T cells were determined by biochemical analysis as reported previously (Phelps, R. G., Turner, A. N., and Rees, A. J. (1996) J. Biol. Chem. 271, 18549-18553). Three nested sets of naturally presented alpha3(IV)NC1 peptides were detectable bound to DR15 molecules. Peptides representative of each nested set bound to DR15 molecules, but almost two-thirds of the alpha3(IV)NC1 peptides studied had as good or better DR15 affinity than those identified as naturally processed. Thus alpha3(IV)NC1 presentation to T cells is determined more by "processing factors" than by the preferences of relatively indiscriminate DR15 molecules. The results have important implications for the use of class II peptide binding data to aid identification of potential T cell epitopes, especially for antigens which, like alpha3(IV)NC1, contain many sequences able to bind class II molecules.
Assuntos
Doença Antimembrana Basal Glomerular/imunologia , Células Apresentadoras de Antígenos/imunologia , Autoantígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Colágeno Tipo IV , Colágeno/imunologia , Antígenos HLA-DR/metabolismo , Sequência de Aminoácidos , Autoantígenos/metabolismo , Colágeno/metabolismo , Mapeamento de Epitopos , Subtipos Sorológicos de HLA-DR , Humanos , Dados de Sequência Molecular , Peptídeos/imunologia , Peptídeos/metabolismo , Ligação Proteica , Relação Estrutura-AtividadeRESUMO
BACKGROUND: Autoimmunity to the NC1 domain of the alpha3 chain of type IV collagen (alpha3(IV)NC1), the Goodpasture antigen, is the cause of spontaneous human antiglomerular basement membrane (anti-GBM) disease, and of anti-GBM nephritis in several animal models. METHODS: We have derived amino acid sequences from alpha3(IV)NC1 for a number of mammalian species (monkey, sheep, pig, dog, rabbit, and rat) by RT-PCR and cDNA cloning. The GBM of some species was studied comparatively for binding to Goodpasture autoantibodies. RESULTS: From this work and other data the sequences of nine mammalian species can be aligned. Regions and residues that may be functionally important are identified. Alpha3(IV)NC1 sequences were found to be less closely conserved across species than alpha1 and alpha2(IV)NC1, 91 to 99% in comparison to a minimum of 97% for alpha1, but these differences were unevenly distributed along the molecule. There was a particularly striking homology between rodent and human sequences in the carboxyl-terminal region. Binding of Goodpasture autoantibodies to rat alpha3(IV)NC1 was poor in comparison with other species. CONCLUSIONS: Comparison of sequences and binding casts doubt on the importance of the carboxyl-terminal region for antibody binding, a region identified as a potential major epitope in previous studies. Sequence comparisons suggest possible reasons for the nephritogenicity of alpha3(IV)NC1 in active models of anti-GBM disease.
Assuntos
Autoantígenos/química , Colágeno Tipo IV , Colágeno/química , Sequência de Aminoácidos , Animais , Cães , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Humanos , Mamíferos , Dados de Sequência Molecular , Coelhos , Ratos , Especificidade da EspécieRESUMO
A minority of patients with Alport syndrome develop anti-GBM disease in their allografts after renal transplantation. Clinically, the renal disease appears indistinguishable from Goodpasture's disease of native kidneys, in which the target of autoantibodies had been identified as the NC1 domain of the alpha 3 chain of type IV collagen, alpha 3(IV)NC1. However, in the majority of cases, Alport syndrome is due to mutations in the gene encoding the alpha 5 chain of type IV collagen, located on the X chromosome. Neither chain is detectable in the glomerular basement membrane (GBM) of most patients with Alport syndrome. We investigated the targets of the alloantibodies of 12 Alport patients who developed post-transplant anti-GBM disease by Western blotting onto recombinant NC1 domains made in insect cells. Binding to these antigens, for both typical Goodpasture and Alport anti-GBM antibodies, was strong and conformation-sensitive. Nine antibodies showed selective binding to alpha 5(IV)NC1. This specificity was confirmed by the demonstration of binding to a 26 kDa band of collagenase-solubilized human GBM, and/or binding to normal epidermal as well as renal basement membranes by indirect immunofluorescence. One antibody showed binding to alpha 5 and alpha 3(IV)NC1, while two showed predominant binding to alpha 3(IV)NC1. All seven patients whose pedigree or mutation analysis showed X-linked inheritance had predominant anti-alpha 5 reactivity. One with predominant anti-alpha 3 reactivity had a COL4A3 mutation. These findings show that human anti-GBM disease can be associated with antibodies directed towards different molecular targets. Alpha 5(IV)NC1 is the primary target in most patients with X-linked Alport syndrome who develop post-transplant anti-GBM disease.
Assuntos
Doença Antimembrana Basal Glomerular/etiologia , Doença Antimembrana Basal Glomerular/imunologia , Isoanticorpos/sangue , Glomérulos Renais/imunologia , Transplante de Rim/efeitos adversos , Transplante de Rim/imunologia , Nefrite Hereditária/imunologia , Nefrite Hereditária/cirurgia , Sequência de Aminoácidos , Doença Antimembrana Basal Glomerular/genética , Sequência de Bases , Membrana Basal/imunologia , Colágeno/genética , Colágeno/imunologia , Primers do DNA/genética , Humanos , Isoantígenos/genéticaRESUMO
We have used a new technique for studying molecular interactions-a resonant mirror biosensor-to identify B cell epitopes within the Goodpasture antigen, which has recently been identified as the non-collagenous domain of the alpha 3-chain of type IV collagen (alpha 3(IV)NC1). Recombinant antigen (r-alpha 3) was immobilized onto the sensing surface of a sample cuvette, and the binding of patients' autoantibodies or a MoAb to the Goodpasture antigen was followed in real time. All patients' sera bound r-alpha 3 in this system, while control sera did not bind. A MoAb inhibited the binding of all patients' autoantibodies to r-alpha 3, from 27% to 90% (mean inhibition 60%), and patients' sera cross-inhibited the binding of each other to the antigen. Binding was inhibited by pre-incubation of autoantibody with both native sheep alpha 3(IV)NC1 and purified human alpha 3(IV)NC1 monomers. Inhibition experiments using soluble overlapping peptides from human alpha 3(IV)NC1 identified putative B cell epitopes. These results suggest that there is a major immunodominant epitope on the Goodpasture antigen, and that there is very limited heterogeneity in the autoantibody response in Goodpasture's disease. The resonant mirror biosensor can be successfully used to monitor antibody-antigen binding using polyclonal sera, and to map epitopes on autoantigens.
Assuntos
Doença Antimembrana Basal Glomerular/imunologia , Autoantígenos/análise , Técnicas Biossensoriais , Colágeno Tipo IV , Colágeno/análise , Mapeamento de Epitopos , Epitopos Imunodominantes/análise , Sequência de Aminoácidos , Humanos , Dados de Sequência Molecular , Proteínas Recombinantes/análiseRESUMO
Biochemical analysis of HLA class II-associated peptides from antigen-pulsed cells is a potentially useful approach to the analysis of antigen processing and presentation because it examines directly which antigen-derived peptides are presented. This is especially advantageous in the analysis of self-antigen presentation where conventional approaches utilizing antigen-specific T cells may be biased by the presence of self-tolerance. However, successful biochemical analysis has been reported for only one exogenous antigen and no autoantigens. We have used a novel analytical approach coupling biochemical data with the reported properties of class II-associated peptides to characterize the peptides derived from a clinically relevant autoantigen presented on the disease-associated class II type. Incubating the target of autoimmune attack in patients with Goodpasture's disease, the 230-amino acid NC1 domain of the alpha3 chain of type IV collagen (Goodpasture antigen, alpha3(IV)NC1), with human B cells homozygous for HLA-DR15, the allele carried by 80% of patients, we find that alpha3(IV)NC1 is presented as at least two sets of three to five peptides centered on common core sequences (nested sets). Synthetic peptides containing these core sequences bind to HLA-DR15 with intermediate affinity (IC50, 1.1-6 microM).
Assuntos
Autoantígenos/metabolismo , Colágeno Tipo IV , Antígenos HLA-DR/metabolismo , Peptídeos/metabolismo , Sequência de Aminoácidos , Doença Antimembrana Basal Glomerular/imunologia , Apresentação de Antígeno , Autoantígenos/química , Autoantígenos/genética , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linhagem Celular , Colágeno/química , Colágeno/genética , Colágeno/metabolismo , Subtipos Sorológicos de HLA-DR , Humanos , Técnicas In Vitro , Cinética , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/genética , Ligação ProteicaRESUMO
Goodpasture's, or anti-glomerular basement membrane, disease is an uncommon, usually severe disease caused by autoimmunity to a component of certain basement membranes. Alport's syndrome is an inherited, degenerative disorder that affects specific basement membranes. The two are linked by the involvement of type-IV collagen (basement membrane collagen) in their pathogenesis.
Assuntos
Doença Antimembrana Basal Glomerular/diagnóstico , Nefrite Hereditária/diagnóstico , Doença Antimembrana Basal Glomerular/patologia , Doença Antimembrana Basal Glomerular/cirurgia , Membrana Basal/patologia , Colágeno/análise , Imunofluorescência , Humanos , Glomérulos Renais/patologia , Transplante de Rim/patologia , Microscopia Eletrônica , Nefrite Hereditária/patologia , Nefrite Hereditária/cirurgia , PrognósticoRESUMO
Proteinase 3 was purified from human neutrophils and used in ELISA to examine sera from 150 patients with systemic vasculitis. It was found to be the major target of autoantibodies in Wegener's granulomatosis, and anti-proteinase 3 antibodies were also found in some patients with microscopic polyarteritis. Anti-proteinase 3 antibodies were associated with a chronic relapsing course.