Clinical, biochemical and molecular aspects of the talassemic syndromes in the population of Pernambuco State

Orientador: Fernando Ferreira CostaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias MedicasResumo: A talassemia ß é uma doença hereditária freqüente da Hb e tem sido encontrada em praticamente todas as populações estudadas. A ocorrência dessas síndromes no Brasil tem sido estudada ao longo do tempo, entretanto, por causa das limitações nas metodologias utilizadas em muitas pesquisas, os dados de prevalência e diversidade são incompletos. Além disso, como conseqüência da composição étnica do nosso país, miscigenada por elementos de origens européia, africana, asiática e indígena, e desigualmente distribuída, a incidência da talassemia pode variar de região para região. Este estudo tem como objetivo mostrar caracteríticas clínicas, bioquímicas e moleculares das síndromes talassêmicas em população do estado de Pernambuco. Foram estudados 117 pacientes não relacionados, sendo 11 diagnosticados com talassemia ß maior, 36 talassemia ß intermediária e 70 com a interação S/ß talassemia, acompanhados na Fundação HEMOPE. A caracterização molecular foi feita por técnicas de PCR e seqüenciamento. A caracterização dos alelos ß talassêmicos revelou 15 diferentes mutações, sendo que 4 delas correspondem a 84,3% dos alelos ß talassêmicos, nas seguintes proporções: 54,9% IVS-I-6 (T-»C), 15,2% IVS-I-5 (G-»C), 7,9% códon 39 (C-»T) e 6,1% IVS-I-1 (G-»A). Foram encontradas outras mutações raras, pela primeira vez descritas no Brasil: IVS-II-849 (A-»G), poli-A (T-»C), - 29 (A-»G), Códon 30 (A-»C), IVS-I-2 (T-»C), IVS-II-837 (T-»G), Códons 106/107 (+G), além das mutações IVS-I-5 (G-»A) e -88 (C-»T). Uma nova mutação foi descrita: códon 12 (-C). Foram encontrados 30 pacientes homozigotos IVS-I-6 (T-»C) e tal mutação mostrou uma forte associação com o haplótipo VI. A mutação IVS-I-5 (G-»C) esteve relacionada ao haplótipo I, diferentemente do encontrado em outras populações (haplótipo VII) em que esta mutação é prevalente, podendo sugerir uma origem diferente para esta mutação no Brasil. A deleção -a3.7 kb esteve presente em 4,2% dos pacientes homozigotos para talassemia ß e em 15,7% dos S/ß tal, enquanto a aaaanti 3.7kb foi encontrada em 5,7% dos S/ß tal. O polimorfismo XmnI esteve presente em 6,1% dos pacientes com ß tal homozigota e em apenas 1,4% dos S/ß tal. Com relação ao alelo UGT1A1, foi visto que pacientes com genótipos (TA)7 / (TA)7 e (TA)7 / (TA)8 apresentaram maiores níveis de bilirrubina não conjugada e parecem ter maior probabilidade de desenvolver colelitíase. No Brasil, embora a composição étnica da população seja heterogênea, as mutações mais comuns são de origem Mediterrânea; Pernambuco pode ser considerado uma exceção já que cerca de 16,0% da população talassêmica possui mutações de origem Asiática e 10,8% são de origem africana. A diversidade de mutações e suas respectivas freqüências diferem do encontrado em outras populações brasileiras já estudadas, como a do Sudeste, onde 4 mutações também respondem pela maioria (97%) dos casos, porém a mutação predominante é a ß039 (C-»T)Abstract: ß Thalassemia is a frequent inherited disease of the Hb molecule found in the majority of populations and distributed worldwide. The prevalence of this syndrome in Brazil has been studied for a long time, but due to limitations in the methodology of some research, data on prevalence and clinical diversity are not fully complete. Furthermore, as a consequence of our ethnic composition, mixed with an uneven distribuition of European, African, Asian and Indian native populations, the incidence of thalassemia may vary greatly from one region to another. This study aims to show clinical features, and also biochemical and molecular data of our thalassemia syndromes in a population setting of thalassemia patients in the State of Pernambuco. We studied 117 non-related patients, 11 of them with ß thalassemia major, 36 ß with thalassemia intermedia and 70 with the S/ß thalassemia interaction, followed regularly at the Fundação HEMOPE ¿ Recife - Brazil. Molecular characterization was performed by PCR techniques and DNA sequencing. Characterization of ß thalassemia alleles showed 15 different mutations, 4 of which corresponded to 84.3% of the ß thalassemia alleles, in the following proportions: 54.9% IVS-I-6 (T-»C), 15.2% IVS-I-5 (G-»C), 7.9% codon 39 (C-»T) and 6.1% IVS-I-1 (G»A). Other rare mutations were found and for the first time in Brazil, such as: IVS-II-849 (A-»G), poly-A (T?C), -29 (A?G), codon 30 (A-»C), IVS-I-2 (T-»C), IVS-II-837 (T-»G), codons 106/107 (+G), as well as IVS-I-5 (G-»A) and -88 (C-»T) mutations. A new mutation is also described: codon 12 (-C). We found 30 homozygous patients for the IVS-I-6 (T-»C) mutation, which showed a strong association with the ß gene haplotype VI. The IVS-I-5 (G-»C) mutation was related to the ß gene haplotype I, differently from that found in other populations studied (ß haplotype VII) where it is more prevalent, suggesting a different origin for this mutation in Brazil. The -a3.7 kb deletion was present in 4.2% of ß thalassemia homozygous patients and in 15.7% of the S/ß thalassemia patients, whereas the aaaanti3.7kb was found in 5.7% of them. The XmnI polymorphism was present in 6.1% of the homozygous ß thalassemia patients and in only 1.4% of the S/ß thalassemia individuals. In relation to the UGT1A1 allele, we found that patients with genotypes (TA) 7 / (TA) 7 and (TA) 7 / (TA) 8 showed higher levels of non-conjugated bilirrubin and seem to be more prone to developing gall stones. In Brazil, although the ethnic composition is markedly heterogeneous, the most common mutations are of Mediterranean origin; Pernambuco may be a curious exception to this, since around 16.0% of the thalassemia population have mutations of Asian origin and 10.8% of African origin. In conclusion, the diversity of the mutations found and their frequencies greatly differ from those found in other Brazilian populations studied previously, for example in the Southeast where only four thalassemia mutations are responsible for the majority (97%) of the thalassemia cases, although the commonest mutation is the ß039 (C-»T)MestradoCiencias BasicasDoutor em Clínica Médic

Adhesive and functional properties of red blood cells, neurotrophils and platelets in patients with hemoglobinopathy SC, HbS-Beta thalassemia and thalassemia intermedia

Orientador: Fernando Ferreira CostaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias MedicasResumo: O estado inflamatório crônico que ocorre na doença falciforme (DF) é decorrente de diversos fatores que se interligam e se retroalimentam, formando um ciclo inflamatório permanente. Estudos prévios sobre as propriedades adesivas e funcionais das células são restritos à forma homozigota do gene da HbS (SS). No entanto, trabalhos que avaliem essas características celulares, que possam contribuir para o esclarecimento da heterogeneidade clínica em outros grupos de DF e talassemia intermediária (TI), são escassos na literatura. O objetivo desse trabalho foi avaliar a capacidade adesiva de células vermelhas, neutrófilos e plaquetas, quimiotaxia dos neutrófilos, os níveis plasmáticos das citocinas inflamatórias e o stress oxidativo na DF e ß-TI. Dessa maneira foram selecionados pacientes com DF: SS (n=20), SC (n=20), 3 grupos com S/ß talassemia - S/ß-IVS-I-6 (T->C) (n=17), S/ß-IVS-I-5 (G->C) (n=16), S/ß-Códon39 (C??T) (n=12) - e TI homozigotos para a mutação IVS-I-6 (T->C) (n=20), acompanhados na Fundação HEMOPE. As técnicas utilizadas no desenvolvimento desse estudo foram: ensaio de quimiotaxia (ChemoTx) para avaliação da capacidade migratória dos neutrófilos, adesão estática para determinação da adesão basal das células, citometria de fluxo para avaliar a produção de ROS e a expressão de moléculas de adesão, e ELISA para determinar a atividade da superóxido dismutase (SOD) e a dosagem das citocinas. Para avaliação de nossos resultados, todos os grupos de pacientes foram comparados ao grupo controle AA: a adesão de neutrófilos e plaquetas mostrou-se significativamente aumentada em todos dos grupos de DF; somente os grupos SS e SC apresentaram capacidade quimiotática significativamente aumentada, assim como a adesão de células vermelhas e a expressão das moléculas de adesão CD36 e CD49d. Os níveis plasmáticos das citocinas IL1-ß, IL-6, IL-8 e TNF-a mostraram-se significativamente aumentados no grupo SS, e nos demais grupos de DF apresentaram uma distribuição heterogênea. Observamos um aumento significativo na produção de ROS em células vermelhas, mononucleares e neutrófilos de todos os grupos de DF, exceto para os grupos S/ß nas células vermelhas. Além disso, a atividade plasmática da SOD mostrou-se reduzida nos grupos SS, SC e S/ß-Cd39. A adesão dos neutrófilos, células vermelhas e plaquetas foi significativamente maior nos pacientes com TI, assim como a expressão das moléculas CD36 e CD49d nas células vermelhas e a capacidade quimiotática dos neutrófilos. Nesses pacientes, a produção de ROS e os níveis plasmáticos das citocinas foram significativamente aumentados, enquanto que a atividade enzimática da SOD foi significativamente reduzida. Apesar da doença SC possuir uma clínica mais branda, nossos dados sugerem que neutrófilos, glóbulos vermelhos e plaquetas desses pacientes possuem características adesivas e quimiotáticas semelhantes às encontradas nas células de pacientes com AF. Além disso, nossos resultados sugerem que quanto maiores os níveis de HbA na S/ß talassemia, menor a adesão de neutrófilos, células vermelhas e plaquetas, podendo explicar as diferenças clínicas encontradas nesses pacientes em função do genótipo. É possível que o aumento da aderência, da capacidade quimiotática, da produção de ROS, das citocinas e diminuição do mecanismo antioxidante, observados neste estudo, contribuam nas complicações clínicas encontradas na ß-TI, tais como hipertensão pulmonar e úlceras de perna. Estudos adicionais podem contribuir para o entendimento das diferenças na apresentação clínica desses pacientes.Abstract: The chronic inflammatory state that occurs in sickle cell disease (SCD) is due to several factors that are interlinked and feeds back to a permanent inflammatory cycle. Previous studies about the adhesive properties and functional cells are restricted to the homozygous form of the HbS gene (SS). However, studies that assess the cellular characteristics that may contribute to the clarification of clinical heterogeneity in other groups of SCD and thalassemia intermedia (TI), are scarce in the literature. The aim of this study was to evaluate the adhesive properties of red blood cells (RBC), platelets and neutrophils (NS), NS chemotaxis, inflammatory cytokine plasma levels and oxidative stress in SCD and ß-TI patients. Thus, we selected patients with different SCD genotypes: SS (n=20), SC (n=20), three groups of HbS/ß thalassemia - HbS/ß39 (C->T) (n=12), HbS/IVSI- 5 (G->C) (n=16), and HbS/IVS-I-6 (T->C) (n=17) - and patients with homozygous thalassemia intermedia IVS-I-6 (T->C) - followed regularly at the Fundação HEMOPE - Brazil. The techniques used in the development of this study were: chemotaxis assay (ChemoTx) to evaluate the migratory ability of neutrophils, basal adhesion was compared using static adhesion assays, flow cytometry to assess the production of ROS and expression of adhesion molecules, and ELISA to determine the superoxide dismutase (SOD) activity and cytokine plasma levels. For evaluation of our results, all groups of patients were compared with the AA control group: the neutrophil and platelet adhesions were significantly increased in all groups of SCD, only the SS and SC groups showed significant increase in the chemotactic ability, as well as the RBC adhesion and the expression of adhesion molecules CD36 and CD49d. All the SCD groups investigated showed an increase in IL-6 plasma levels. IL1-ß levels were significantly higher in the S/ß-IVS-I-5 (G??C), S/ß-Cd39 and SS groups. Plasma levels of IL-8 were increased only in the SS and SC groups, however TNF-a levels were significantly higher in SS and the three groups with HbS-ß thalassemia. NS and mononuclear cell ROS production was significantly increased in all SCD groups, however red blood ROS production was higher only in the SS and SC groups. Moreover, the SOD plasma activity was shown to be reduced in groups SS, SC and S/ß-Cd39. The NS, RBC and platelets adhesion was significantly higher in TI patients, as well as the expression of molecules CD36 and CD49d in RBC and chemotactic ability of NS. In these patients, the ROS production and cytokines plasma levels were significantly increased, while SOD plasma activity was significantly reduced. Although SC disease has a milder clinical manifestations, our data suggest that NS, RBC and platelets of these patients have chemotactic and adhesive characteristics similar to those found in cells of patients with SS. Moreover, our results suggest that the higher levels of HbA in S/ß thalassemia reduce the NS, RBC and platelets adhesion and may explain the clinical differences found in these patients, according to genotype. It is possible that the increase in the cell adherence, chemotactic capacity, ROS production, of cytokines levels and the reduction in antioxidant mechanism, observed in this study, contribute to several clinical complications of ß-TI, such as pulmonary hypertension and leg ulcers. Further studies may contribute to our understanding of the differences in the clinical presentation of these patients.DoutoradoMedicina ExperimentalDoutor em Fisiopatologia Medic

Mannose-binding lectin 2 (MBL2) gene polymorphisms do not influence frequency of infections in chronic lymphocytic leukemia patients

Background: Infectious complications represent the main cause of morbidity and mortality in chronic lymphocytic leukemia. It has been reported that polymorphisms of the mannosebinding lectin 2 (MBL2) genes are correlated with MBL protein serum levels and, consequently, are associated with the development of infectious diseases. Objective: The purpose of this study was to investigate the possible association between MBL2 gene polymorphisms and risk of infection in chronic lymphocytic leukemia patients. Methods: Peripheral blood samples from 116 chronic lymphocytic leukemia patients were collected; after genomic DNA extraction, real time polymerase chain reaction was used to determine the polymorphisms of the promoter region and exon 1 of the MBL2 gene. Results: A high frequency of Binet stage A (p-value = 0.005) and absence of splenomegaly (p-value = 0.002) were observed in patients with no infection; however, variant alleles/ genotypes and haplotypes of this gene had no impact on the risk of infection. Conclusion: To the authors' knowledge, this is the first study describing the association between MBL2 polymorphisms and infectious disease in chronic lymphocytic leukemia. Although it was not possible to demonstrate any influence of MBL2 polymorphisms as a genetic modulator of infection in chronic lymphocytic leukemia, the authors believe that the present data are clinically relevant and provide the basis for future studies

Association of the SOD2 Polymorphism (Val16Ala) and SOD Activity with Vaso-occlusive Crisis and Acute Splenic Sequestration in Children with Sickle Cell Anemia

Submitted by Paulo Silva ([email protected]) on 2019-11-18T13:17:51Z No. of bitstreams: 1 Association of the SOD2 Polymorphism (Val16Ala) and SOD Activity with Vaso-occlusive Crisis and Acute Splenic Sequestration in Children with Sickle Cell Anemia.pdf: 335007 bytes, checksum: a614766bb4931821c7294ae8bbbed5e6 (MD5)Approved for entry into archive by Paulo Silva ([email protected]) on 2019-11-18T13:55:11Z (GMT) No. of bitstreams: 1 Association of the SOD2 Polymorphism (Val16Ala) and SOD Activity with Vaso-occlusive Crisis and Acute Splenic Sequestration in Children with Sickle Cell Anemia.pdf: 335007 bytes, checksum: a614766bb4931821c7294ae8bbbed5e6 (MD5)Made available in DSpace on 2019-11-18T13:55:11Z (GMT). No. of bitstreams: 1 Association of the SOD2 Polymorphism (Val16Ala) and SOD Activity with Vaso-occlusive Crisis and Acute Splenic Sequestration in Children with Sickle Cell Anemia.pdf: 335007 bytes, checksum: a614766bb4931821c7294ae8bbbed5e6 (MD5) Previous issue date: 2018FACEPEUniversidade de Pernambuco. Instituto de Ciências Biológicas. Recife, PE, Brasil.Universidade de Pernambuco. Instituto de Ciências Biológicas. Recife, PE, Brasil / Universidade Federal Rural de Pernambuco. Programa de Pós-Graduação em Biotecnologia. Recife, PE, Brasil.Universidade de Pernambuco. Instituto de Ciências Biológicas. Recife, PE, Brasil.Universidade de Pernambuco. Instituto de Ciências Biológicas. Recife, PE, Brasil.Universidade Federal de Pernambuco. Recife, PE, Brasil.Universidade de Pernambuco. Instituto de Ciências Biológicas. Recife, PE, Brasil.Fundação Oswaldo Cruz. Instituto Aggeu Magalhães. Recife, PE, Brasil.Universidade Federal de Pernambuco. Recife, PE, Brasil / Fundação de Hematologia e Hemoterapia de Pernambuco. Recife, PE, Brasil.Fundação de Hematologia e Hemoterapia de Pernambuco. Recife, PE, Brasil.Universidade de Pernambuco. Instituto de Ciências Biológicas. Recife, PE, Brasil.Universidade Federal de Pernambuco. Recife, PE, Brasil.Fundação de Hematologia e Hemoterapia de Pernambuco. Recife, PE, Brasil.Universidade de Pernambuco. Instituto de Ciências Biológicas. Recife, PE, Brasil / Fundação de Hematologia e Hemoterapia de Pernambuco. Recife, PE, Brasil.The SOD2 polymorphism Val16Ala T→C influences the antioxidative response. This study investigated the association of the SOD2 polymorphism and superoxide dismutase (SOD) activity with the vaso-occlusive crisis (VOC) and acute splenic sequestration (ASS) in children with sickle cell anemia (SCA). One hundred ninety-five children with SCA aged 1-9 years old were analyzed. The TC and CC genotypes were associated with lower SOD activity compared with the TT genotype (p=0.0321; p=0.0253, respectively). Furthermore, TC and CC were more frequent in patients with VOC or ASS (p=0.0285; p=0.0090, respectively). These results suggest that the SOD2 polymorphism associated with low SOD activity could be a susceptibility factor for the occurrence of VOC and ASS

Whole-exome sequencing indicates FLG2 variant associated with leg ulcers in Brazilian sickle cell anemia patients

Although sickle cell anemia results from homozygosity for a single mutation at position 7 of the beta-globin chain, the clinical aspects of this condition are very heterogeneous. Complications include leg ulcers, which have a negative impact on patients' quality of life and are related to the severity of the disease. Nevertheless, the complex pathogenesis of this complication has yet to be elucidated. To identify novel genes associated with leg ulcers in sickle cell anemia, we performed whole-exome sequencing of extreme phenotypes in a sample of Brazilian sickle cell anemia patients and validated our findings in another sample. Our discovery cohort consisted of 40 unrelated sickle cell anemia patients selected based on extreme phenotypes: 20 patients without leg ulcers, aged from 40 to 61 years, and 20 with chronic leg ulcers. DNA was extracted from peripheral blood leukocytes and used for whole-exome sequencing. After the bioinformatics analysis, eight variants were selected for validation by Sanger sequencing and TaqMan (R) genotyping in 293 sickle cell anemia patients (153 without leg ulcers) from two different locations in Brazil. After the validation, Fisher's exact test revealed a statistically significant difference in a stop codon variant (rs12568784 G/T) in the FLG2 gene between the GT and GG genotypes (P = 0.035). We highlight the importance of rs12568784 in leg ulcer development as this variant of the FLG2 gene results in impairment of the skin barrier, predisposing the individual to inflammation and infection. Additionally, we suggest that the remaining seven variants and the genes in which they occur could be strong candidates for leg ulcers in sickle cell anemia. Impact statement To our knowledge, the present study is the first to use whole-exome sequencing based on extreme phenotypes to identify new candidate genes associated with leg ulcers in sickle cell anemia patients. There are few studies about this complication; the pathogenesis remains complex and has yet to be fully elucidated. We identified interesting associations in genes never related with this complication to our knowledge, especially the variant in the FLG2 gene. The knowledge of variants related with leg ulcer in sickle cell anemia may lead to a better comprehension of the disease's etiology, allowing prevention and early treatment options in risk genotypes while improving quality of life for these patients24411932939FAPESP – Fundação de Amparo à Pesquisa Do Estado De São Paulo2014/00984-3; 2015/24029-

NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data