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1.
Philos Trans R Soc Lond B Biol Sci ; 379(1901): 20230062, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38497254

RESUMO

Interactions between animals and microbes are ubiquitous in nature and strongly impact animal physiology. These interactions are shaped by the host immune system, which responds to infections and contributes to tailor the associations with beneficial microorganisms. In many insects, beneficial symbiotic associations not only include gut commensals, but also intracellular bacteria, or endosymbionts. Endosymbionts are housed within specialized host cells, the bacteriocytes, and are transmitted vertically across host generations. Host-endosymbiont co-evolution shapes the endosymbiont genome and host immune system, which not only fights against microbial intruders, but also ensures the preservation of endosymbionts and the control of their load and location. The cereal weevil Sitophilus spp. is a remarkable model in which to study the evolutionary adaptation of the immune system to endosymbiosis owing to its binary association with a unique, relatively recently acquired nutritional endosymbiont, Sodalis pierantonius. This Gram-negative bacterium has not experienced the genome size shrinkage observed in long-term endosymbioses and has retained immunogenicity. We focus here on the sixteen antimicrobial peptides (AMPs) identified in the Sitophilus oryzae genome and their expression patterns in different tissues, along host development or upon immune challenges, to address their potential functions in the defensive response and endosymbiosis homeostasis along the insect life cycle. This article is part of the theme issue 'Sculpting the microbiome: how host factors determine and respond to microbial colonization'.


Assuntos
Simbiose , Gorgulhos , Animais , Gorgulhos/genética , Gorgulhos/microbiologia , Grão Comestível , Peptídeos Antimicrobianos , Imunidade
2.
Heliyon ; 10(5): e26903, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439846

RESUMO

The extensive and indiscriminate use of chemical pesticides in agriculture has led to adverse effects on human health, environmental pollution, and the emergence of pesticide-resistant pests. To mitigate these challenges, the development of environmentally friendly alternatives is crucial, with biopesticides emerging as promising solutions such as peptides. Legume seeds naturally contain diverse insecticidal peptides or proteins to combat pest attacks. One such peptide is PA1b (Pea Albumin 1, subunit b), a 37 amino acid extracted from pea seeds (Pisum sativum). PA1b has shown significant potential in controlling cereal weevils (Sitophilus spp.), a major pest of stored cereals. Here, we screened PA1b-like peptides in five wild seeds of vetches (Vicia sativa subsp. sativa) from the Middle East. Using a comprehensive set of biochemical, biological, and molecular techniques, we characterized different PA1b homologs and assessed their toxicity and expression profiles. Our results reveal that PA1b homolog from Vicia sativa subsp. sativa originating from turkey displays outstanding insecticidal activity against Sitophilus oryzae through binding to the receptor site found in the midgut of the insect. Moreover, it exhibits a strong cytotoxic effect against Sf9 cells. This cysteine-rich peptide shows sequence identity and the same hydrophobic pole as AG41, a tenfold more toxic isoform of PA1b from Medicago truncatula. Such observations pave the way for the development of bioinsecticides, with PA1b-like peptides as lead compounds.

3.
Ann Oncol ; 28(8): 1817-1824, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28459938

RESUMO

BACKGROUND: The ARTemis trial previously reported that addition of neoadjuvant bevacizumab (Bev) to docetaxel (D) followed by fluorouracil, epirubicin and cyclophosphamide (D-FEC) in HER2 negative breast cancer improved the pathological complete response (pCR) rate. We present disease-free survival (DFS) and overall survival (OS) with central pathology review. PATIENTS AND METHODS: Patients were randomized to 3 cycles of D followed by 3 cycles of FEC (D-FEC), ±4 cycles of Bev (Bev + D-FEC). DFS and OS were analyzed by treatment and by central pathology reviewed pCR and Residual Cancer Burden (RCB) class. RESULTS: A total of 800 patients were randomized [median follow-up 3.5 years (IQR 3.2-4.4)]. DFS and OS were similar across treatment arms [DFS hazard ratio (HR)=1.18 (95% CI 0.89-1.57), P = 0.25; OS HR = 1.26 (95% CI 0.90-1.76), P = 0.19). Both local pathology report review and central histopathology review confirmed a significant improvement in DFS and OS for patients who achieved a pCR [DFS HR = 0.38 (95% CI 0.23-0.63), P < 0.001; OS HR = 0.43 (95% CI 0.24-0.75), P = 0.003]. However, significant heterogeneity was observed (P = 0.02); larger improvements in DFS were obtained with a pCR achieved with D-FEC than a pCR achieved with Bev + D-FEC. As RCB class increased, significantly worse DFS and OS was observed (P for trend <0.0001), which effect was most marked in the ER negative group. CONCLUSIONS: The addition of short course neoadjuvant Bev to standard chemotherapy did not demonstrate a DFS or OS benefit. Achieving a pCR with D-FEC is associated with improved DFS and OS but not when pCR is achieved with Bev + D-FEC. At the present time therefore, Bev is not recommended in early breast cancer. CLINICALTRIALS.GOV NUMBER: NCT01093235.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Taxoides/uso terapêutico , Neoplasias da Mama/patologia , Ciclofosfamida/uso terapêutico , Docetaxel , Diagnóstico Precoce , Epirubicina/uso terapêutico , Feminino , Fluoruracila/uso terapêutico , Genes erbB-2 , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Indução de Remissão , Análise de Sobrevida
4.
Ann Oncol ; 28(8): 1832-1835, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28525534

RESUMO

BACKGROUND: We have previously shown lymphocyte density, measured using computational pathology, is associated with pathological complete response (pCR) in breast cancer. The clinical validity of this finding in independent studies, among patients receiving different chemotherapy, is unknown. PATIENTS AND METHODS: The ARTemis trial randomly assigned 800 women with early stage breast cancer between May 2009 and January 2013 to three cycles of docetaxel, followed by three cycles of fluorouracil, epirubicin and cyclophosphamide once every 21 days with or without four cycles of bevacizumab. The primary endpoint was pCR (absence of invasive cancer in the breast and lymph nodes). We quantified lymphocyte density within haematoxylin and eosin (H&E) whole slide images using our previously described computational pathology approach: for every detected lymphocyte the average distance to the nearest 50 lymphocytes was calculated and the density derived from this statistic. We analyzed both pre-treatment biopsies and post-treatment surgical samples of the tumour bed. RESULTS: Of the 781 patients originally included in the primary endpoint analysis of the trial, 609 (78%) were included for baseline lymphocyte density analyses and a subset of 383 (49% of 781) for analyses of change in lymphocyte density. The main reason for loss of patients was the availability of digitized whole slide images. Pre-treatment lymphocyte density modelled as a continuous variable was associated with pCR on univariate analysis (odds ratio [OR], 2.92; 95% CI, 1.78-4.85; P < 0.001) and after adjustment for clinical covariates (OR, 2.13; 95% CI, 1.24-3.67; P = 0.006). Increased pre- to post-treatment lymphocyte density showed an independent inverse association with pCR (adjusted OR, 0.1; 95% CI, 0.033-0.31; P < 0.001). CONCLUSIONS: Lymphocyte density in pre-treatment biopsies was validated as an independent predictor of pCR in breast cancer. Computational pathology is emerging as a viable and objective means of identifying predictive biomarkers for cancer patients. CLINICALTRIALS.GOV: NCT01093235.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Biologia Computacional , Linfócitos do Interstício Tumoral/patologia , Linfócitos/patologia , Terapia Neoadjuvante , Neoplasias da Mama/patologia , Ciclofosfamida/uso terapêutico , Epirubicina/uso terapêutico , Feminino , Fluoruracila/uso terapêutico , Humanos , Contagem de Linfócitos , Reação em Cadeia da Polimerase , Indução de Remissão
5.
Br J Cancer ; 108(4): 866-72, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-23299526

RESUMO

BACKGROUND: Neo-tAnGo, a National Cancer Research Network (NCRN) multicentre randomised neoadjuvant chemotherapy trial in early breast cancer, enroled 831 patients in the United Kingdom. We report a central review of post-chemotherapy histopathology reports on the surgical specimens, to assess the presence and degree of response. METHODS: A central independent two-reader review (EP and HME) of histopathology reports from post-treatment surgical specimens was performed. The quality and completeness of pathology reporting across all centres was assessed. The reviews included pathological response to chemotherapy (pathological complete response (pCR); minimal residual disease (MRD); and lesser degrees of response), laterality, the number of axillary metastases and axillary nodes, and the type of surgery. A consensus was reached after discussion. RESULTS: In all, 825 surgical reports from 816 patients were available for review. Out of 4125 data items there were 347 discrepant results (8.4% of classifications), which involved 281 patients. These involved grading of breast response (169 but only 9 involving pCR vs MRD); laterality (6); presence of axillary metastasis (35); lymph node counts (108); and type of axillary surgery (29). Excluding cases with pCR, only 45% of reports included any comment regarding response in the breast and 30% in the axillary lymph nodes. CONCLUSION: We found considerable variability in the completeness of reporting of surgical specimens within this national neoadjuvant breast cancer trial. This highlights the need for consensus guidelines among trial groups on histopathology reporting, and the participation of histopathologists throughout the development and analysis of neoadjuvant trials.


Assuntos
Neoplasias da Mama/patologia , Projetos de Pesquisa/estatística & dados numéricos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Axila/patologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Feminino , Humanos , Linfonodos/patologia , Metástase Linfática/patologia , Terapia Neoadjuvante , Neoplasia Residual/patologia , Prognóstico , Resultado do Tratamento
6.
Br J Cancer ; 107(8): 1257-67, 2012 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-23047592

RESUMO

BACKGROUND: The National Epirubicin Adjuvant Trial (NEAT) and BR9601 trials tested the benefit of epirubicin when added to cyclophosphamide, methotrexate and 5-fluorouracil (E-CMF) compared with standard CMF in adjuvant chemotherapy for women with early breast cancer. This report details longer follow-up with interesting additional time-dependent analyses. METHODS: National Epirubicin Adjuvant Trial used epirubicin (E) 3-weekly for four cycles followed by classical (c) CMF for four cycles (E-CMF) compared with cCMF for six cycles. BR9601 used E 3-weekly for four cycles followed by CMF 3-weekly for four cycles, compared with CMF 3-weekly for eight cycles. RESULTS: In all, 2391 eligible patients were randomised and with a median 7.4-year follow-up, E-CMF confirmed a significant benefit over CMF in both relapse-free survival (RFS) (78% vs 71% 5 years RFS, respectively, hazard ratio (HR)=0.75 (95% CI: 0.65-0.86), P<0.0001) and overall survival (OS) (84% vs 78% 5 years OS, respectively, HR=0.76 (95% CI: 0.65-0.89), P=0.0007). Interaction of treatment effect and prognostic factors was demonstrated for duplication of chromosome 17 centromeric enumeration (Ch17CEP) as previously reported. Poor prognostic factors at diagnosis (ER and PR negative and HER2 positive) showed time-dependent annual hazard rates for RFS and OS. In univariate analysis, these factors demonstrated more favourable HRs for RFS after 5 years. Treatment effects also suggested a differential benefit for E-CMF within the first 5 years for poor prognosis tumours. CONCLUSION: Longer follow-up has confirmed E-CMF as significantly superior to CMF for all patients. Ch17CEP duplication was the only biomarker that demonstrated significant treatment interaction. Standard poor prognostic factors at diagnosis were time-dependent, and after 5 years disease-free, poor prognosis patients demonstrated favourable HRs for survival.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Epirubicina/administração & dosagem , Adesão à Medicação , Idoso , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Metotrexato/administração & dosagem , Pessoa de Meia-Idade
7.
Breast Cancer Res Treat ; 127(2): 459-69, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21437610

RESUMO

Pathological complete response (pCR) is an important predictor of long-term survival in patients with breast cancer receiving neoadjuvant chemotherapy (NAC). At present, the accuracy of traditional radiological assessments during treatment in predicting pCR is poor. Unidimensional and 3D volumetric ultrasound measurements prior to, after 4 cycles (mid-treatment), and at the end of 8 cycles (end-treatment) of chemotherapy were available from a subset of 55 patients enrolled in Neo-tAnGo, a National Cancer Research Network (NCRN) UK neoadjuvant chemotherapy breast cancer trial. Proportional changes in longest diameter (LD) and volume as well as absolute residual size thresholds were examined for their ability to predict pCR or pCR plus minimal residual disease (pCR/MRD). Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) and likelihood ratios (LRs) were calculated. Receiver-operator characteristic (ROC) curves and logistic regression models were also constructed. At mid-treatment, neither complete radiological response, nor proportional LD or volume changes were found predictive of final pCR. A small residual tumour volume (≤ 1 cm³ vs. > 1 cm³) at mid-treatment, however, was associated with pCR/MRD (P = 0.014). Sensitivity, specificity, PPV, NPV, LR+ and LR- values were 61%, 77%, 61%, 77%, 2.62 and 0.51, respectively. The area under the ROC curve was 0.689 (P = 0.03). Volume ≤ 1 cm³ at mid-treatment was found significant in a logistic regression (OR: 0.194, P = 0.011). At end-treatment, no ultrasound measurements were found predictive of pCR or pCR/MRD. In conclusion, proportional tumour size changes (the basis of the RECIST criteria) were not found predictive of good pathological response, although residual volume ≤ 1 cm³ at mid-treatment was found to be predictive of pCR/MRD. However, multiple volume and LD thresholds were examined and uncorrected P values presented, increasing the possibility of type I errors. Replication in an independent dataset is required.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Terapia Neoadjuvante , Carga Tumoral , Adulto , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasia Residual/diagnóstico por imagem , Neoplasia Residual/tratamento farmacológico , Neoplasia Residual/patologia , Prognóstico , Curva ROC , Sensibilidade e Especificidade , Resultado do Tratamento , Ultrassonografia
8.
J Virol ; 72(11): 8472-6, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9765383

RESUMO

We have studied the immune responses to the two glycoproteins of the Morbillivirus canine distemper virus (CDV) after DNA vaccination of BALB/c mice. The plasmids coding for both CDV hemagglutinin (H) and fusion protein (F) induce high levels of antibodies which persist for more than 6 months. Intramuscular inoculation of the CDV DNA induces a predominantly immunoglobulin G2a (IgG2a) response (Th1 response), whereas gene gun immunization with CDV H evokes exclusively an IgG1 response (Th2 response). In contrast, the CDV F gene elicited a mixed, IgG1 and IgG2a response. Mice vaccinated (by gene gun) with either the CDV H or F DNA showed a class I-restricted cytotoxic lymphocyte response. Immunized mice challenged intracerebrally with a lethal dose of a neurovirulent strain of CDV were protected. However, approximately 30% of the mice vaccinated with the CDV F DNA became obese in the first 2 months following the challenge. This was not correlated with the serum antibody levels.


Assuntos
Vírus da Cinomose Canina/genética , Vírus da Cinomose Canina/imunologia , Cinomose/prevenção & controle , Vacinas de DNA/farmacologia , Vacinas Virais/farmacologia , Animais , Anticorpos Antivirais/biossíntese , Cinomose/imunologia , Cães , Feminino , Glicoproteínas/genética , Glicoproteínas/imunologia , Células HeLa , Hemaglutininas Virais/genética , Hemaglutininas Virais/imunologia , Humanos , Imunidade Celular , Células L , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T Citotóxicos/imunologia , Transfecção , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/imunologia , Proteínas Virais/genética , Proteínas Virais/imunologia
9.
Hum Mutat ; 11(4): 342-3, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9554757

RESUMO

Protein 4.1 is a major component of the junctional complex at the red cell skeleton. Genomic studies have recently evidenced that the encoding gene (EL1 locus) is present in a single copy per haploid genome. Several RFLPs have already been characterized within intron sequences. Here, we describe the first RFLP found within the coding sequence. This polymorphism (C or T at position 2723, in exon 21) does not affect the amino acid sequence (Thr-->Thr). It can be detected by either Dde I restriction digestion of an appropriate PCR product, or simply by SSCP These findings should facilitate analysis of families with 4.1 deficiencies causing hereditary elliptocytosis.


Assuntos
Proteínas do Citoesqueleto , Proteínas de Membrana/genética , Neuropeptídeos , Polimorfismo de Fragmento de Restrição , Polimorfismo Conformacional de Fita Simples , Alelos , Sequência de Bases , Primers do DNA/genética , DNA Complementar/genética , Desoxirribonucleases de Sítio Específico do Tipo II , Éxons , Humanos , Reação em Cadeia da Polimerase
10.
J Virol ; 72(3): 2516-8, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9499116

RESUMO

Plasmids encoding the measles virus hemagglutinin (HA) and nucleoprotein (NP) proteins inoculated into the skin of BALB/c mice by the gene gun method induced both humoral and cytotoxic lymphocyte class I-restricted immune responses. Although intramuscular immunization induces the immunoglobulin G2a (IgG2a) antibody isotype for both antigens, with gene gun immunization, the NP still generated mainly IgG2a and the major isotype induced by the HA was IgG1. Interestingly, gene gun coimmunization of HA and NP plasmids resulted in a dominant IgG1 HA response and the switching of antibodies generated against the NP to the IgG1 isotype.


Assuntos
Antígenos Virais/imunologia , DNA Viral , Hemaglutininas Virais/imunologia , Imunoglobulina G/imunologia , Vacina contra Sarampo/imunologia , Vírus do Sarampo/imunologia , Nucleoproteínas/imunologia , Vacinação , Vacinas Sintéticas/imunologia , Proteínas Virais/imunologia , Animais , Feminino , Hemaglutininas Virais/genética , Isotipos de Imunoglobulinas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Proteínas do Nucleocapsídeo , Nucleoproteínas/genética , Linfócitos T Citotóxicos/imunologia , Proteínas Virais/genética
11.
Br J Haematol ; 99(3): 522-30, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9401060

RESUMO

Unlike previously reported cases with total protein 4.2 deficiency due to mutations in the EPB42 gene, we describe a total deficiency in protein 4.2 with normal EPB42 alleles. Hereditary spherocytosis (HS) was observed in a Japanese woman (unsplenectomized) and her daughter (splenectomized). The mother showed a partial deficiency in band 3 and a proportional reduction in protein 4.2. She was heterozygous for a novel allele of the EPB3 gene, allele Okinawa, which contains the two mutations that define the Memphis II polymorphism (K56E, AAG-->GAG, and P854L, CCG-->CTG) and, additionally, the mutation: G714R, GGG-->AGG, located in a highly conserved position of transmembrane segment 9. The latter change was responsible for HS. In trans to allele Okinawa, the daughter displayed allele Fukuoka: G130R, GGA-->AGA, an allele known to alter the binding of protein 4.2 to band 3. The daughter presented with a more pronounced decrease of band 3, and lacked protein 4.2, resulting in aggravated haemolytic features. Although the father was not available for study, heterozygosity for allele Fukuoka has been documented in another individual who showed no clinical or haematological signs, and a normal content of band 3. We suggest that band 3 Okinawa binds virtually all the protein 4.2 in red cell precursors, band 3 Fukuoka being unable to do so, and that the impossibility of band 3 Okinawa incorporation into the membrane leads to degradation of the band 3 Okinawa protein 4.2 complex. In contrast, band 3 Fukuoka, free of bound protein 4.2, could then incorporate normally into the bilayer. Thus, protein 4.2 would not appear in the daughter's red cell membrane.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/genética , Proteínas Sanguíneas/genética , Mutação , Esferocitose Hereditária/genética , Substituição de Aminoácidos , Proteína 1 de Troca de Ânion do Eritrócito/deficiência , Proteínas Sanguíneas/deficiência , Feminino , Humanos
12.
Blood ; 90(1): 414-20, 1997 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-9207478

RESUMO

We present two novel alleles of the anion-exchanger 1 (AE1) gene, allele Coimbra and allele Mondego. Allele Coimbra (V488M, GTG --> ATG) affects a conserved position in the putative second ectoplasmic loop of erythrocyte band 3. In 15 simple heterozygotes, it yielded a mild form of hereditary spherocytosis (HS) with band 3 deficiency (-20% +/- 2%) and a reduced number of 4,4'-diisothiocyano-1,2-diphenylethane-2,2'-disulfonate (H2DIDS) binding sites (-35%). However, two additional heterozygotes presented with an aggravated HS and a more pronounced reduction of band 3 (-40%) and of H2DIDS binding sites (-48%). They carried, in trans to allele Coimbra, allele Mondego, defined by two mutations: E40K, GAG --> AAG, the known mutation Montefiore, and P147S, CCT --> TCT, a novel mutation, both located in the cytoplasmic domain of band 3. Allele Mondego itself resulted in no clinical or hematologic HS signs in the simple heterozygous state. Yet it yielded a slight decrease in band 3 (-6% to -12%) and in the number of H2DIDS binding sites (-19%). Thus, the more pronounced decrease in band 3 in the two compound heterozygotes derived from the additive effects of two unequally expressed AE1 alleles, resulting in a more severe clinical picture.


Assuntos
Alelos , Proteína 1 de Troca de Ânion do Eritrócito/genética , Esferocitose Hereditária/genética , Proteína 1 de Troca de Ânion do Eritrócito/deficiência , Feminino , Humanos , Masculino , Linhagem
13.
Am J Hematol ; 54(3): 242-8, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9067504

RESUMO

We describe a case of spherocytosis in a French child splenectomized at age 10 years. The parents were devoid of any clinical, hematological, or biochemical abnormalities. Following splenectomy, the proposita exhibited a reduction of red cell membrane ankyrin. The variable number of dinucleotide repeats associated with the erythroid ankyrin gene (ANK1) were studied at the genomic level. The father, the mother, and the proposita had the AC14/AC11, AC14/AC14, and AC14/AC11 genotypes, respectively, although the proposita exhibited a pattern consistent with an AC14,-combination at the cDNA level. We thought there could be a de novo mutation in the ANK1 allele of paternal origin (AC11). A false paternity seemed most unlikely. Based on PCR-amplification of exons, SSCP analysis, and, when appropriate, nucleotide sequencing, we found a one-nucleotide deletion in codon 146 (exon 6): 521delC, ACG-->AG. This placed in phase a TAG triplet normally overlapping codons 150 and 151. Early interruption of translation presumably accounted for the premature degradation of mutant mRNA. Restriction analysis confirmed the presence of the mutation in the proposita and its absence in the parents. The variant was designated ankyrin Bugey.


Assuntos
Anquirinas/genética , Mutação da Fase de Leitura , Esferocitose Hereditária/genética , Éxons/genética , Feminino , Humanos , Masculino , RNA Mensageiro/análise , Mapeamento por Restrição
14.
Br J Haematol ; 96(1): 70-6, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9012689

RESUMO

We report three novel variants of band 3 associated with hereditary spherocytosis: band 3 Foggia (311delC; ACCCAC-->ACCAC), band 3 Napoli I (447insT; TCT-->TTCT) and band 3 Napoli II (1783N; ATC-->AAC). The first two mutations resulted in premature termination of translation, making one haploid set of band 3 mRNA unavailable. Since it affected a highly conserved position at the terminal end of transmembrane domain 11, the third mutation prevented one haploid set of band 3 from becoming incorporated or stabilized into the membrane. These three mutations resulted in a reduction of the band 3 level in the red cell membrane (by 20-25%) and were dominantly transmitted. The D38A substitution (GAC-->GCC) is a low frequency change of band 3. In one compound heterozygote D38A/Napoli II, a markedly aggravated picture required early splenectomy. In contrast, the D38A change was not associated with deterioration in another compound heterozygote, carrying in trans, the previously recorded R760W mutation (CGG-->TGG). In the aggravated case, SSCP analysis did not exhibit any additional change in the two EPB3 alleles. Nor did it show any alteration in the exons of the two ANK1 alleles, and the aggravating factor remained elusive. The D38A alteration should be regarded as an innocuous polymorphism.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/genética , Mutação , Polimorfismo Genético , Esferocitose Hereditária/genética , Análise Mutacional de DNA , Membrana Eritrocítica/química , Feminino , Deleção de Genes , Genes Dominantes , Humanos , Masculino , Proteínas de Membrana/análise , Ácidos Nucleicos/análise , Linhagem
15.
Blood ; 88(3): 1062-9, 1996 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-8704215

RESUMO

We describe an 18-year-old with moderate hereditary spherocytosis. The condition was associated with a 35% decrease in band 3. The underlying mutation was Arg to stop at codon 150 (CGA-->TGA) and was designated R150X, which defined allele Lyon of the EPB3 gene. The inheritance pattern was dominant. However, the mother, who also carried the allele Lyon, had a milder clinical presentation and only a 16% decrease of band 3. We suggested that the father had transmitted a modifying mutation that remained silent in the heterozygous state. Nucleotide sequencing after single strand conformation polymorphism analysis of the band 3 cDNA and promoter region revealed a G-->A substitution at position 89 from the cap site in the 5'-untranslated region, designated 89G-->A, which defined allele Genas. A ribonuclease protection assay showed that (1) the allele Genas (father) resulted in a 33% decrease in the amount of band 3 mRNA, (2) the reduction caused by the allele Lyon (mother) was 42%, and (3) the compound heterozygous state for both alleles (proband) resulted in a 58% decrease. These results suggest that some mildly deleterious alleles of the EPB3 gene are compensated for by the normal allele in the heterozygous state. They are shown through the aggravation of the clinical picture, based on more obvious molecular alterations when they occur in trans to an allele causing a manifest reduction of band 3 membrane protein concentration.


Assuntos
Alelos , Proteína 1 de Troca de Ânion do Eritrócito/deficiência , Esferocitose Hereditária/genética , Proteína 1 de Troca de Ânion do Eritrócito/genética , Sequência de Bases , Heterozigoto , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Mutação Puntual , Polimorfismo Conformacional de Fita Simples
16.
Br J Haematol ; 93(4): 828-34, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8703812

RESUMO

We report a case of apparently recessive hereditary spherocytosis in an Italian child. The proband exhibited a reduction of overall ankyrin in the red cell membrane. The parents were free of any haematological manifestations. The VNDR associated with the ankyrin gene (ANK1) were consistent with the following diplotypes: AC11/ AC14 (father), AC14/AC14 (mother) and AC11/AC14 (child). The cDNA of the patient disclosed the expression of the AC11 allele only. As a consequence, we put forward the hypothesis of a de novo inactivation affecting the ankyrin allele of maternal origin (AC14) and accounting for the disease. PCR amplification of exons, SSCP analysis and nucleotide sequencing disclosed a polymorphism: GAC --> AAC; Asp --> Asn in codon 328 of exon 10, and a one-nucleotide deletion : CTG --> CG in codon 573 of the exon 16. This frameshift mutation placed in phase the TGA triplet that normally overlaps codons 636 and 637. Termination of translation near the middle of ankyrin mRNA coding sequence resulted, presumably, in its premature degadation. The present allele has been designated allele Napoli.


Assuntos
Anquirinas/genética , Mutação da Fase de Leitura , Esferocitose Hereditária/genética , Sequência de Aminoácidos , Sequência de Bases , Criança , Membrana Eritrocítica/metabolismo , Éxons , Feminino , Humanos , Dados de Sequência Molecular , Mutação , Polimorfismo Genético
17.
Br J Haematol ; 91(4): 804-10, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8547122

RESUMO

We studied a large Swiss family with dominantly inherited hereditary spherocytosis and band 3 (anion exchanger 1, AE1) deficiency. Band 3 cDNA was analysed by single-strand conformation polymorphism analysis and nucleotide sequencing. A new point mutation was found: G771D (GGC-->GAC). This change was present in all eight investigated patients but absent in four healthy members of the family. It is located at a highly conserved position in the middle of transmembrane segment 11, introducing a negative charge in a stretch of 16 apolar or neutral residues. None of the six amino-acid substitutions already known in this region as being associated with band 3 deficiency were recorded. To rule out any major transcriptional or post-transcriptional defect, we evaluated the amount of band 3 mRNA by RNase mapping using a band 3-protein 4.1 chimaeric probe. Similar mRNA amounts were present in patients and controls. Our results strengthen the view that some amino-acids, that are well conserved throughout the AE family, may be crucial for the insertion and/or the stabilization of band 3 within the lipid bilayer. At the present time, most of the mutations altering such residues are located in the C-terminal region of band 3.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/genética , Proteínas do Citoesqueleto , Neuropeptídeos , Mutação Puntual , Esferocitose Hereditária/genética , Animais , Proteína 1 de Troca de Ânion do Eritrócito/deficiência , Sequência de Bases , Galinhas , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/patologia , Feminino , Humanos , Masculino , Proteínas de Membrana/genética , Camundongos , Dados de Sequência Molecular , Linhagem , Polimorfismo Conformacional de Fita Simples , RNA Mensageiro/análise , Ratos , Alinhamento de Sequência , Esferocitose Hereditária/cirurgia , Esplenectomia , Truta
18.
Br J Haematol ; 88(3): 534-40, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7819065

RESUMO

Allele alpha LELY is a low-expression allele of the erythroid spectrin alpha-gene. It carries mutations in exon 40 (alpha V/41 polymorphism) and intron 45, respectively, and is associated with partial skipping of exon 46. The latter phenomenon is thought to impair the recruitment of alpha-chains by beta-chains, and would eventually account for the low-expression character. When it occurs in trans to an alpha-allele responsible for hereditary elliptocytosis (alpha HE allele; alpha HE/alpha LELY diplotype), allele alpha LELY enhances the severity of elliptocytosis. Because allele alpha LELY is widespread, we anticipated that it would occasionally carry HE determinants. These variants of allele alpha LELY will be designated alpha HE-LELY allele. The HE component was the known alpha 28 Arg-->His mutation. This alpha HE-LELY allele was investigated within the alpha HE-LELY/alpha LELY diplotype, a diplotype not described before. Except for the neonatal period, the presentation was mild. In a consistent manner, the alpha LELY component in cis of the alpha HE mutation counteracted the like component in trans.


Assuntos
Eliptocitose Hereditária/genética , Espectrina/genética , Alelos , Sequência de Bases , Eliptocitose Hereditária/patologia , Eritrócitos/patologia , Feminino , Expressão Gênica , Humanos , Masculino , Dados de Sequência Molecular , Mutação , Linhagem , Polimorfismo Genético , Mapeamento por Restrição
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