Thesis (M.Sc. (Clinical Pathology))--Mahidol University, 1978.

Serological discrepancies in matching blood group antigens between donors and patients for blood transfusion may lead to alloimmunisation, especially in multiply transfused patients. Blood group genotyping (BGG) has contributed in reducing this issue. ABO, Fy and Jk antigens are among those to be causative for alloimmunisation through transfusion or pregnancy. The number of alleles of these clinically significant blood groups is ever increasing. Currently, all commercially available high-throughput BGG platforms are only based on pre-defined polymorphisms. Consequently, novel or rare alleles that might have clinical significance are not identified. Next generation sequencing (NGS) circumvents this issue by providing high-throughput comprehensive genotyping of blood group genes in discovery mode to find all existing and novel mutations. Accordingly, a large number of individuals can be genotyped in a single run. Here, we describe an NGS-based method coupled with long-range polymerase chain reaction (LR-PCR) for high-throughput, rapid and extensive genotyping of FY, JK and ABO blood group genes. The Ion Torrent Personal Genome Machine (PGMTM) was used for sequencing the entire FY, JK and ABO blood group genes including flanking regions. Accordingly, high resolution genotyping was obtained. 53 genomic DNA samples were sequenced and genotyped for FY, 67 for JK and 47 for ABO. Sequencing data were aligned to the gene reference sequence derived from the human genome (hg19) to analyse variants. Analysis was accomplished by software packages, such as Ion Torrent SuiteTM plugins. Sanger sequencing of cDNA and cDNA clones was used to confirm findings in the JK gene. The sequencing data had a coverage depth of more than 5000x for FY, 700x for JK and 600x for ABO. NGS data matched with the serological phenotypes of FY alleles FY*A, FY*B and FY*02 Null main polymorphisms, such as FY*A/FY*B (125G > A) in exon 2 and (-67 T > C) in the promotor region. JK variant analysis revealed that the JK*01W.01 allele (130G > A) is common (10/67 samples) with normal antigenicity. The previously described silencing polymorphism (810G > A), leading to a purported JK*B null allele, restores a splice site and does not correlate with loss of Jkb antigenicity (10/67 samples). JK intron analysis revealed several new JK alleles described in this thesis. All 7 exons, introns and the flanking regions of the ABO gene were covered by only four amplicons. Several rare O alleles were found, such as O73 and O75, while one suggested novel O allele was characterised by a missense SNP 482G > A (Arg161His) in exon 7. The ABO reference sequence from hg19 appeared to resemble (O01 and O02) alleles. The intronic SNPs might be used to distinguish between alleles more accurately as a correlation of the intronic SNPs with the alleles was noted for the homozygous O alleles. It is predicted that NGS-based genotyping will replace not only microarray-based genotyping but also serology in the blood group typing of individuals, with great advancements in technology and molecular knowledge being expected in the near future.

Extensive use of the organophosphate diazinon has led to its accumulation in aquatic environments and negative effects on fish health. Most studies focus on the effects of short term exposure to high levels of organophosphate pesticides. This research was conducted to assess the effect of chronic sub-lethal exposure to 0, 0.01, and 0.1 mg/L diazinon for 15 and 30 days on blood parameters and histopathological damage in alligator gar, Atractosteus spatula. Fish exposed to either concentration were motionless, produced excess mucous, had lighter skin color, and had skin lesions. Blood indices of red blood cells, leukocytes and hematocrit values significantly decreased but there was no significant change in mean cell volume. Hemoglobin values significantly increased in fish exposed to the low dose for 15 days, but significantly decreased for the other exposure doses and times. On the contrary, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration values significantly increased in fish exposed to both concentrations and duration times. Leukocyte differentials showed significant decreases in lymphocytes with significant increases of monocytes in fish exposed to the high dose in both exposure times. The most frequent biomarker for exposure to organophosphate pesticides is the inhibition of cholinesterase (ChE). Diazinon significantly reduced plasma ChE activity in a dose-dependent manner, with 62% and 72% in the low and high concentrations for 30 days, respectively. Plasma ChE could be determined from peripheral blood samples and did not require sacrifice of the fish. Fish exposed to either diazinon concentration or duration time developed histopathological changes in skin, gills, liver, and kidney tissues. The skin lesions were on the head and body, and progressed into deep ulcerations. The histopathological changes in the liver included hepatic vacuoles, swollen hepatocytes, steatosis, aggregation of macrophages, necrosis, and hepatic fibrosis. Also, exposed fish demonstrated vacuolar degeneration in the hematopoietic tissues of the kidney. Gills showed epithelial hyperplasia in the secondary lamellae. In conclusion, long term exposure to sub-lethal concentrations of diazinon induced significant changes in hematological indices and histopathological alteration in various tissues. Plasma ChE can be used to monitor diazinon exposure in wild gar populations.

Diss. (sammanfattning) Linköping : Univ., 2004. / Härtill 5 uppsatser.

Introdução: O Transplante de Célula Tronco Hematopoiética (TCTH) é um tratamento potencialmente curativo para muitas desordens hematológicas. A disparidade HLA entre doador e receptor é um fator crítico para os resultados do TCTH. No entanto novas evidencias tem demonstrado que outros fatores como a fonte de célula tronco, o tipo de condicionamento e fatores relacionados aos doadores, entre eles o sexo, a idade e o status sorológico para Citomegalovirus (CMV) podem influenciar os desfechos do procedimento. Objetivo: Avaliar as características dos doadores de medula óssea e seu impacto nos desfechos do TCTH em um centro do Sul do Brasil. Métodos: Foram avaliadas retrospectivamente as características dos doadores como sexo, idade, presença de exposição previa ao CMV, incompatibilidade ABO e suas relações com a ocorrência de doença do enxerto contra hospedeiro (DECH) aguda e crônica, a mortalidade relacionada ao transplante (do inglês tumor related mortality – TRM) sobrevida livre de doença (SLD) e sobrevida Global (SG) em todos os pacientes submetidos a TCTH alogênico em um único centro durante o período de 1994 a 2012. Resultados: 347 pacientes foram incluídos na análise. O TCTH aparentado foi significativamente mais freqüente que o não aparentado (81.2 x 18.7), a mediana de idade foi de 34 (1-61) para os receptores e 33 (1-65) para os doadores. Na analise multivariada a presença de DECH agudo (33% vs 47%) p=0,04 e ter doadores mais idosos (>40 anos) foram associados a uma redução de SG em 5 anos (41% vs 52%) p=0,038. Ter um doador acima de 40 anos aumenta significativamente a incidência de DECH aguda (52% vs 65,8%) p=0,03 e crônica (60% vs 43%) p=0,015. O sexo do doador, presença de CMV e incompatibilidade ABO não tiveram influencia nos desfechos. Conclusão: Em um centro único avaliado receber um transplante de CTH de doadores acima de 40 anos aumenta a incidência de DECH aguda e crônica e influencia negativamente na SG. / Background: Hematopoietic Stem cell Transplantation (HSCT) is a curative treatment for many patients with hematological disorders. Donor – recipient genetic disparity, especially involving the HLA systems is a critical factor for HSCT outcome There are increasing evidences, however that other issues as source of stem cell, conditioning regimen, donor gender, age and CMV infection can affect HSCT outcomes. Objective: To study the influence of donor’s characteristics on the HSCT outcomes in a south Brazilian population subjected to allogeneic SCT in a single center. Methods: We retrospectively evaluated donor characteristics such as gender, age, CMV serologic status and ABO compatibility and its relation to the occurrence of acute and chronic graft versus host disease (GVHD), disease free survival (DFS) and overall survival (OS) in all patients submitted to related and unrelated allogeneic HSCT, performed between 1994 and 2012. Results: Overall 347 consecutives HSCT were included in this analysis. Related HSCT was significantly more frequent than unrelated (81.2% x 18.7%); donor and recipient median age were 34 (1- 61) and 33 (1-65), respectively. In the multivariate analyses, presence acute GVHD (33%vs 47%)p=0.04 ,with relative risk and donors older than 40 years old was associated with lower probability of OS in 5 years (41% vs 52%) p=0,038 and higher rate of acute (65.8%vs 52%) p=0.03 and chronic GVHD (43% vs 60%) p=0,015. Donor’s sex, CMV status, ABO incompatibility have not influenced 5-years survival. Conclusions: In a single center population of patients submitted to related and unrelated HSCT in southern Brazil donor older then 40 years of age is a factor negatively influencing HSCT outcome.

Introdução: O Transplante de Célula Tronco Hematopoiética (TCTH) é um tratamento potencialmente curativo para muitas desordens hematológicas. A disparidade HLA entre doador e receptor é um fator crítico para os resultados do TCTH. No entanto novas evidencias tem demonstrado que outros fatores como a fonte de célula tronco, o tipo de condicionamento e fatores relacionados aos doadores, entre eles o sexo, a idade e o status sorológico para Citomegalovirus (CMV) podem influenciar os desfechos do procedimento. Objetivo: Avaliar as características dos doadores de medula óssea e seu impacto nos desfechos do TCTH em um centro do Sul do Brasil. Métodos: Foram avaliadas retrospectivamente as características dos doadores como sexo, idade, presença de exposição previa ao CMV, incompatibilidade ABO e suas relações com a ocorrência de doença do enxerto contra hospedeiro (DECH) aguda e crônica, a mortalidade relacionada ao transplante (do inglês tumor related mortality – TRM) sobrevida livre de doença (SLD) e sobrevida Global (SG) em todos os pacientes submetidos a TCTH alogênico em um único centro durante o período de 1994 a 2012. Resultados: 347 pacientes foram incluídos na análise. O TCTH aparentado foi significativamente mais freqüente que o não aparentado (81.2 x 18.7), a mediana de idade foi de 34 (1-61) para os receptores e 33 (1-65) para os doadores. Na analise multivariada a presença de DECH agudo (33% vs 47%) p=0,04 e ter doadores mais idosos (>40 anos) foram associados a uma redução de SG em 5 anos (41% vs 52%) p=0,038. Ter um doador acima de 40 anos aumenta significativamente a incidência de DECH aguda (52% vs 65,8%) p=0,03 e crônica (60% vs 43%) p=0,015. O sexo do doador, presença de CMV e incompatibilidade ABO não tiveram influencia nos desfechos. Conclusão: Em um centro único avaliado receber um transplante de CTH de doadores acima de 40 anos aumenta a incidência de DECH aguda e crônica e influencia negativamente na SG. / Background: Hematopoietic Stem cell Transplantation (HSCT) is a curative treatment for many patients with hematological disorders. Donor – recipient genetic disparity, especially involving the HLA systems is a critical factor for HSCT outcome There are increasing evidences, however that other issues as source of stem cell, conditioning regimen, donor gender, age and CMV infection can affect HSCT outcomes. Objective: To study the influence of donor’s characteristics on the HSCT outcomes in a south Brazilian population subjected to allogeneic SCT in a single center. Methods: We retrospectively evaluated donor characteristics such as gender, age, CMV serologic status and ABO compatibility and its relation to the occurrence of acute and chronic graft versus host disease (GVHD), disease free survival (DFS) and overall survival (OS) in all patients submitted to related and unrelated allogeneic HSCT, performed between 1994 and 2012. Results: Overall 347 consecutives HSCT were included in this analysis. Related HSCT was significantly more frequent than unrelated (81.2% x 18.7%); donor and recipient median age were 34 (1- 61) and 33 (1-65), respectively. In the multivariate analyses, presence acute GVHD (33%vs 47%)p=0.04 ,with relative risk and donors older than 40 years old was associated with lower probability of OS in 5 years (41% vs 52%) p=0,038 and higher rate of acute (65.8%vs 52%) p=0.03 and chronic GVHD (43% vs 60%) p=0,015. Donor’s sex, CMV status, ABO incompatibility have not influenced 5-years survival. Conclusions: In a single center population of patients submitted to related and unrelated HSCT in southern Brazil donor older then 40 years of age is a factor negatively influencing HSCT outcome.

Introdução: O Transplante de Célula Tronco Hematopoiética (TCTH) é um tratamento potencialmente curativo para muitas desordens hematológicas. A disparidade HLA entre doador e receptor é um fator crítico para os resultados do TCTH. No entanto novas evidencias tem demonstrado que outros fatores como a fonte de célula tronco, o tipo de condicionamento e fatores relacionados aos doadores, entre eles o sexo, a idade e o status sorológico para Citomegalovirus (CMV) podem influenciar os desfechos do procedimento. Objetivo: Avaliar as características dos doadores de medula óssea e seu impacto nos desfechos do TCTH em um centro do Sul do Brasil. Métodos: Foram avaliadas retrospectivamente as características dos doadores como sexo, idade, presença de exposição previa ao CMV, incompatibilidade ABO e suas relações com a ocorrência de doença do enxerto contra hospedeiro (DECH) aguda e crônica, a mortalidade relacionada ao transplante (do inglês tumor related mortality – TRM) sobrevida livre de doença (SLD) e sobrevida Global (SG) em todos os pacientes submetidos a TCTH alogênico em um único centro durante o período de 1994 a 2012. Resultados: 347 pacientes foram incluídos na análise. O TCTH aparentado foi significativamente mais freqüente que o não aparentado (81.2 x 18.7), a mediana de idade foi de 34 (1-61) para os receptores e 33 (1-65) para os doadores. Na analise multivariada a presença de DECH agudo (33% vs 47%) p=0,04 e ter doadores mais idosos (>40 anos) foram associados a uma redução de SG em 5 anos (41% vs 52%) p=0,038. Ter um doador acima de 40 anos aumenta significativamente a incidência de DECH aguda (52% vs 65,8%) p=0,03 e crônica (60% vs 43%) p=0,015. O sexo do doador, presença de CMV e incompatibilidade ABO não tiveram influencia nos desfechos. Conclusão: Em um centro único avaliado receber um transplante de CTH de doadores acima de 40 anos aumenta a incidência de DECH aguda e crônica e influencia negativamente na SG. / Background: Hematopoietic Stem cell Transplantation (HSCT) is a curative treatment for many patients with hematological disorders. Donor – recipient genetic disparity, especially involving the HLA systems is a critical factor for HSCT outcome There are increasing evidences, however that other issues as source of stem cell, conditioning regimen, donor gender, age and CMV infection can affect HSCT outcomes. Objective: To study the influence of donor’s characteristics on the HSCT outcomes in a south Brazilian population subjected to allogeneic SCT in a single center. Methods: We retrospectively evaluated donor characteristics such as gender, age, CMV serologic status and ABO compatibility and its relation to the occurrence of acute and chronic graft versus host disease (GVHD), disease free survival (DFS) and overall survival (OS) in all patients submitted to related and unrelated allogeneic HSCT, performed between 1994 and 2012. Results: Overall 347 consecutives HSCT were included in this analysis. Related HSCT was significantly more frequent than unrelated (81.2% x 18.7%); donor and recipient median age were 34 (1- 61) and 33 (1-65), respectively. In the multivariate analyses, presence acute GVHD (33%vs 47%)p=0.04 ,with relative risk and donors older than 40 years old was associated with lower probability of OS in 5 years (41% vs 52%) p=0,038 and higher rate of acute (65.8%vs 52%) p=0.03 and chronic GVHD (43% vs 60%) p=0,015. Donor’s sex, CMV status, ABO incompatibility have not influenced 5-years survival. Conclusions: In a single center population of patients submitted to related and unrelated HSCT in southern Brazil donor older then 40 years of age is a factor negatively influencing HSCT outcome.

<p>Uvod: Pojam &quot;sekretor&rdquo; ili &bdquo;nesekretor&quot; se odnosi na sposobnost pojedinca da luči antigene krvnih grupa ABO sistema u telesnim tečnostima. Određivanje ABO krvne grupe i sekretornog statusa, testom inhibicije hemaglutinacije pljuvačke i Lewis fenotipa na eritrocitima su važni u kliničkoj i forenzičkoj medicini, u odnosu na etiopatogenezu mnogih bolesti. Nesekretorstvo ABO krvnogrupne supstance je udruženo sa če&scaron;ćom pojavom autoimunih inflamatornih oboljenja među kojima su i seronegativne spondiloartropatije. Veća učestalost seronegativnih spondiloartropatija među osobama koje imaju HLA-B27 antigen predstavlja polaznu osnovu stanovi&scaron;ta da genetski faktori u kombinaciji sa faktorima sredine utiču na pojavu seronegativnih spondiloartropatija u genetski predisponiranih individua. Teza istražuje značaj testa inhibicije hemaglutinacije plijuvačke i određivanja ABO i Lewis fenotipa na eritrocitim u dijagnostici seronegativnih spondiloartropatija. Ciljevi i hipoteze: Cilj istraživanja je bio da se utvrdi učestalost nesekretora i sekretora ABO krvnogrupne supstance i Lewis fenotipa u grupi obolelih od seronegativnih spondiloartropatija i izvr&scaron;iti poređenje rezultata u odnosu na grupu zdravih ispitanka. Pretpostavljeno je da postoji značajno veći broj nesekretora ABO krvnogrupne supstance u obolelih od seronegativnih spondiloartropatija u odnosu na zdrave ispitanike. Pretpostavljeno je i da postoji značajno veća učestalost nesekretora ABO krvnogrupne supstance u obolelih od seronegativnih spondiloartropatija sa negativnim HLA-B27 antigenom. Pretpostavljeno je da kod osoba obolelih od seronegativnih spondiloartropatija dolazi do promene Lewis fenotipa na eritrocitima u odnosu na sekretorni status u pljuvačci. Metode: Sprovedena je longitudinalna prospektibvna studija. Ispitanici stariji od &scaron;est godina oba pola podeljeni su u dve randomizovane grupe. Eksperimentalnu grupu sačinjavalo je 110 ispitanika sa dijagnozom oboljenja iz grupe seronegativnih spondiloartropatija. Kontrolnu grupu sačinjavalo je 103 dobrovoljna davaoca krvi, bez dijaghnoze oboljenja iz grupe seronegativnih spondiloartropatija. Ispitanicima kontrolne i eksperimentalne grupe određena je pripadnosti ABO krvnogrupnom sistemu, sekretorni status i Lewis fenotip, dok je osobama eksperimentalne grupe određen i fenotip HLA-B27. Uključujući kriterijumi osim navedenog bili su da ispitivane osobe ženskog pola nisu trudinice i da ispitanici obe grupe nisu primali transfuziju krvi tri meseca pre uključivanja u istraživanje. Rezultati: Rezultati istraživanja ukazuju da nesekretori ABO krvnogrupne supstance imaju 1,63 puta veći rizik (veću učestalost), oboljevanja od seronegativnih spondiloartropatija u odnosu na zdravu populaciju ispitanika, kao i da smanjena ekspresija Lewis (b) antigena predstavlja doprinoseći faktor razvoja seronegativnih spondiloartropatija. Ustanovljeno je da pod uticajem seronegativnih spondiloartropatija dolazi do izmene Lewis fenotipa na eritrocitima obolelih. Verovatnoća dokazivanja oboljenja iz grupe seronegativnih spondilartropatija među obolelima veća je za 11% kod nesekretora fenotipa HLA-B27- u odnosu na obolele nesekretore fenotipa HLA-B27+. Zaključak: Sekretorni status i Lewis fenotip predstavljaju zasebne dijagnostičke biohemijske markere nezavisne od HLA-B27 antigena koji doprinose ranijem otkrivanju osoba koje imaju predispoziciju razvoja oboljenja iz grupe seronegativnih spondiloartropatija.</p> / <p>Introduction:The term secretory state referes to ability of individual to secrete ABO blood group antigens in body fluids. Determination of the ABO blood group antigens and secretory status by hemagglutionation inhibition test using saliva as well as Lewis phenotype on erythrocytes are important in clinical and forensic medicine, in relation to the etiopathogenesis of many diseases. Non secretory status of ABO blood groupantegens is related with higher incidence of autoimmune inflammatory disease which include seronegative spondyloarthropathyes. Increased frequency of seronegative spondyloarthropathies among people who have the HLA-B27 antigen is starting point of the view that genetic factors in combination with environmental factors influence the occurence of seronegative spondyloarthropathies in genetically predisposed individuals. The tesis explores the significance of the hemagglutionation inhibition test of saliva and determination of ABO and Lewis antigens in diagnostics of seronegativespondyloarthropathyes. Goals and hypothesis: The aim of this study was to determine the frequency of non secretors and secretors of ABO blood group antigens and Lewis phenotype in a group of patient with seronegative spondyloarthropathies and make comparsion to the healthy examined group. It was assumed that there is a significantly higher number of non secretors of ABO blood group antigens among the patients with seronegative spondyloarthropathies compared to healthy examined persons. It was assumed that there is a significantly higher number of non secretors of ABO blood group antigens among the patients with seronegative spondyloarthropathies who do not have HLA-B27 antigen. It was assumed that in patients with seronegative spondyloarthropathies Lewis phenotype on erythrocits can be changed in relation to the secretory status in the saliva. Methods: We performed a prospective longitudinal study. Respondants older than six years of both gender were divided into two randomized groups. Experimental group is consisted of 110 patients diagnosed with seronegative spondyloarthropathy. The control group consisted of 103 blood donors who did not have diagnosed disease from the group of seronegative spondyloarthropathies. To the subjects of the control and experimental groups was determined ABO blood group antigens, secretory status and Lewis phenotype, while to the subjects of experimental group also was designated HLA-B27 phenotype. Including criteria other than the above were that among female respondants were not pregnant, and that both groups of respondants did not receive a blood transfusion three months before joining the study. Results: The resuts of the study showed that non secretors of ABO blood group antigens have a 1,63 times higher rise (higher incidence) of developing disease from the group of seronegative spondyloarthropathies compared to a healthy population of subjects, as well as that decreased expression of Lewis antigens (b) represents a contributing factor for development of seronegativespondyloarthropathies. It was found that under the influence of seronegative spondyloarthropathies there are changes in Lewis phenotype on erythrocytes of patients. It was found that under the influence of seronegative spondyloarthropathies there are changes in Lewis phenotype on erythrocytes of patients. Probability for confirmation seronegative spondyloarthropathies is higher for 11% among non secretors who have HLA-B27 negative phenotype in comparison to non secretors who have HLA-B27 positive phenotype. Conclusion: Secretory status and Lewis phenotype are separate diagnostic biochemical markers independent of HLA-B27 antigen that contribute to the early detection of people who have a predisposition of the disease from the group of seronegative spondyloarthropathies.</p>

A Doença de Alzheimer (DA) é a principal causa de demência na população idosa e tende a se tornar um grave problema de saúde pública com o aumento da expectativa de vida da população mundial. A perda progressiva de memória, principal sintoma da demência em pacientes com DA, é atribuída a danos sinápticos e à perda neuronal desencadeadas pelo desequilíbrio entre a produção e a depuração do peptídeo A?. Evidências surgidas nos últimos 20 anos apontam os oligômeros solúveis de A? (A?O), produtos de agregação do peptídeo A?, como as principais espécies neurotóxicas na DA. Por conta disso, e também pela ausência de métodos diagnósticos pre-mortem e tratamento eficientes para essa demência, a busca por anticorpos conformacionais específicos para A?O está em ascensão. Testes clínicos com IgG anti-A? resultaram em efeitos colaterais inflamatórios mediados pela porção não variável Fc. Então, anticorpos conformacionais artificiais do tipo scFv, desprovidos de porção Fc, foram selecionados contra A?O. Dentre eles, está NUsc1, que é neuroprotetor contra A?O em cultura primária de neurônios. Neste trabalho, avaliamos a toxicidade de A?Os na linhagem de neuroblastoma humano SH-SY5Y diferenciada em neurônios maduros e comparamos a neuroproteção conferida por diferentes anticorpos contra A?Os, por ensaio de viabilidade celular com MTT. Também avaliamos a especificidade de NUsc1 por A?O comparativamente a lisozima monomérica e oligomérica em ensaio de ELISA, já que outros anticorpos conformacionais reconhecem epítopo compartilhado por estados oligoméricos de outras proteínas amiloidogênicas. Para a validação de células SH-SY5Y como modelo in vitro de neurônios maduros, a diferenciação foi induzida com ácido retinoico e BDNF e as células foram marcadas para as proteínas MAP2 e NeuN em ensaio de imunofluorescência. Células submetidas ao protocolo de diferenciação apresentaram aumento dos níveis dessas proteínas, mudança morfológica condizente com o esperado na maturação neuronal. Posteriormente, o desafio da cultura com A?O indicou morte celular dose-dependente e reversão desta morte segundo a dose administrada dos anticorpos 6E10 e NU-4. Obtivemos um sinal cerca de 400 vezes maior no reconhecimento de A?O por NUsc1 que para oligômeros de lisozima, quando presentes na mesma concentração, indicando forte especificidade de NUsc1 por A?O. Além disso, NUsc1 purificado em sistema de gelfiltração em HPLC não apresenta citotoxicidade em concentração equivalente a dos anticorpos 6E10 e NU-4 em ensaios de neuroproteção em cultura de SH-SY5Y diferenciada, sugerindo que, se NUsc1 for tão eficiente quanto estas IgG\'s, este poderá ser usado em dose não citotóxica. Portanto, podemos concluir que NUsc1 apresenta grande potencial como ferramenta diagnóstica e terapêutica para a DA, mas que mais experimentos para expandir sua validação e potencial ainda são necessários. / Alzheimer\'s Disease (AD) is the leading cause of dementia in the elderly population and tends to become a serious public health problem with increasing life expectancy of the world\'s population. Progressive memory loss, the main symptom of dementia in patients with AD, is attributed to synaptic damage and neuronal loss triggered by imbalance between production and clearance of the A? peptide. Evidence from the last 20 years indicates that soluble A? oligomers (A?O), A? peptide aggregation products, as the main neurotoxic species in AD. Because of this, and also because of the absence of efficient pre-mortem diagnostic and treatment methods for this dementia, the search for conformational antibodies specific for A?O is on the rise. Clinical tests with anti-A? IgG\'s resulted in inflammatory side effects mediated by the non-variable Fc portion. Then, artificial conformational antibodies of the scFv type, lacking the Fc portion, were selected against A?O. Among them is NUsc1, which is neuroprotective against A?O in primary neuronal culture. In this work, we evaluated the toxicity of A?Os in the differentiated SH-SY5Y human neuroblastoma line in mature neurons and compared the neuroprotection conferred by different antibodies against A?O types by MTT cell viability assay. We also evaluated the specificity of NUsc1 for A?O compared to monomeric and oligomeric lysozyme in the ELISA assay, since other conformational antibodies recognize epitope shared by oligomeric states of other amyloidogenic proteins. For the validation of SH-SY5Y cells as an in vitro model of mature neurons, differentiation was induced with retinoic acid and BDNF and the cells were labeled for MAP2 and NeuN proteins in immunofluorescence assay. Cells submitted to the differentiation protocol presented increased levels of these proteins, a morphological change consistent with the expected neuronal maturation. Subsequently, the challenge of culture with A?O indicated dose-dependent cell death and reversion of this death according to the administered dose of 6E10 and NU-4 antibodies. We obtained a 400-fold higher signal in the recognition of A?O by NUsc1 than for lysozyme oligomers, when present at the same concentration, indicating strong specificity of A?O by NUsc1. In addition, NUsc1 purified on HPLC gel-filtration system does not exhibit cytotoxicity at concentration equivalent to 6E10 and NU-4 antibodies in neuroprotection assays in differentiated SH-SY5Y culture, suggesting that, if NUsc1 is as efficient as these IgG\'s, it may be used in a non-cytotoxic dose. Therefore, we can conclude that NUsc1 presents great potential as a diagnostic and therapeutic tool for AD, but that further experiments to expand its validation and potential are still necessary.

A Doença de Alzheimer (DA) é a principal causa de demência na população idosa e tende a se tornar um grave problema de saúde pública com o aumento da expectativa de vida da população mundial. A perda progressiva de memória, principal sintoma da demência em pacientes com DA, é atribuída a danos sinápticos e à perda neuronal desencadeadas pelo desequilíbrio entre a produção e a depuração do peptídeo A?. Evidências surgidas nos últimos 20 anos apontam os oligômeros solúveis de A? (A?O), produtos de agregação do peptídeo A?, como as principais espécies neurotóxicas na DA. Por conta disso, e também pela ausência de métodos diagnósticos pre-mortem e tratamento eficientes para essa demência, a busca por anticorpos conformacionais específicos para A?O está em ascensão. Testes clínicos com IgG anti-A? resultaram em efeitos colaterais inflamatórios mediados pela porção não variável Fc. Então, anticorpos conformacionais artificiais do tipo scFv, desprovidos de porção Fc, foram selecionados contra A?O. Dentre eles, está NUsc1, que é neuroprotetor contra A?O em cultura primária de neurônios. Neste trabalho, avaliamos a toxicidade de A?Os na linhagem de neuroblastoma humano SH-SY5Y diferenciada em neurônios maduros e comparamos a neuroproteção conferida por diferentes anticorpos contra A?Os, por ensaio de viabilidade celular com MTT. Também avaliamos a especificidade de NUsc1 por A?O comparativamente a lisozima monomérica e oligomérica em ensaio de ELISA, já que outros anticorpos conformacionais reconhecem epítopo compartilhado por estados oligoméricos de outras proteínas amiloidogênicas. Para a validação de células SH-SY5Y como modelo in vitro de neurônios maduros, a diferenciação foi induzida com ácido retinoico e BDNF e as células foram marcadas para as proteínas MAP2 e NeuN em ensaio de imunofluorescência. Células submetidas ao protocolo de diferenciação apresentaram aumento dos níveis dessas proteínas, mudança morfológica condizente com o esperado na maturação neuronal. Posteriormente, o desafio da cultura com A?O indicou morte celular dose-dependente e reversão desta morte segundo a dose administrada dos anticorpos 6E10 e NU-4. Obtivemos um sinal cerca de 400 vezes maior no reconhecimento de A?O por NUsc1 que para oligômeros de lisozima, quando presentes na mesma concentração, indicando forte especificidade de NUsc1 por A?O. Além disso, NUsc1 purificado em sistema de gelfiltração em HPLC não apresenta citotoxicidade em concentração equivalente a dos anticorpos 6E10 e NU-4 em ensaios de neuroproteção em cultura de SH-SY5Y diferenciada, sugerindo que, se NUsc1 for tão eficiente quanto estas IgG\'s, este poderá ser usado em dose não citotóxica. Portanto, podemos concluir que NUsc1 apresenta grande potencial como ferramenta diagnóstica e terapêutica para a DA, mas que mais experimentos para expandir sua validação e potencial ainda são necessários. / Alzheimer\'s Disease (AD) is the leading cause of dementia in the elderly population and tends to become a serious public health problem with increasing life expectancy of the world\'s population. Progressive memory loss, the main symptom of dementia in patients with AD, is attributed to synaptic damage and neuronal loss triggered by imbalance between production and clearance of the A? peptide. Evidence from the last 20 years indicates that soluble A? oligomers (A?O), A? peptide aggregation products, as the main neurotoxic species in AD. Because of this, and also because of the absence of efficient pre-mortem diagnostic and treatment methods for this dementia, the search for conformational antibodies specific for A?O is on the rise. Clinical tests with anti-A? IgG\'s resulted in inflammatory side effects mediated by the non-variable Fc portion. Then, artificial conformational antibodies of the scFv type, lacking the Fc portion, were selected against A?O. Among them is NUsc1, which is neuroprotective against A?O in primary neuronal culture. In this work, we evaluated the toxicity of A?Os in the differentiated SH-SY5Y human neuroblastoma line in mature neurons and compared the neuroprotection conferred by different antibodies against A?O types by MTT cell viability assay. We also evaluated the specificity of NUsc1 for A?O compared to monomeric and oligomeric lysozyme in the ELISA assay, since other conformational antibodies recognize epitope shared by oligomeric states of other amyloidogenic proteins. For the validation of SH-SY5Y cells as an in vitro model of mature neurons, differentiation was induced with retinoic acid and BDNF and the cells were labeled for MAP2 and NeuN proteins in immunofluorescence assay. Cells submitted to the differentiation protocol presented increased levels of these proteins, a morphological change consistent with the expected neuronal maturation. Subsequently, the challenge of culture with A?O indicated dose-dependent cell death and reversion of this death according to the administered dose of 6E10 and NU-4 antibodies. We obtained a 400-fold higher signal in the recognition of A?O by NUsc1 than for lysozyme oligomers, when present at the same concentration, indicating strong specificity of A?O by NUsc1. In addition, NUsc1 purified on HPLC gel-filtration system does not exhibit cytotoxicity at concentration equivalent to 6E10 and NU-4 antibodies in neuroprotection assays in differentiated SH-SY5Y culture, suggesting that, if NUsc1 is as efficient as these IgG\'s, it may be used in a non-cytotoxic dose. Therefore, we can conclude that NUsc1 presents great potential as a diagnostic and therapeutic tool for AD, but that further experiments to expand its validation and potential are still necessary.