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Filamentous fungus Purpureocillium lilacinum is an emerging pathogen that infects immunocompromised and immunocompetent individuals and is resistant to several azole molecules. Although azole resistance mechanisms are well studied in Aspergillus sp. and Candida sp., there are no studies to date reporting P. lilacinum molecular response to these molecules. The aim of this study was to describe P. lilacinum molecular mechanisms involved in antifungal response against fluconazole and itraconazole. Transcriptomic analyses showed that gene expression modulation takes place when P. lilacinum is challenged for 12 h with fluconazole (64 μg/mL) or itraconazole (16 μg/mL). The antifungals acted on the ergosterol biosynthesis pathway, and two homologous genes coding for cytochrome P450 51 enzymes were upregulated. Genes coding for efflux pumps, such as the major facilitator superfamily transporter, also displayed increased expression in the treated samples. We propose that P. lilacinum develops antifungal responses by raising the expression levels of cytochrome P450 enzymes and efflux pumps. Such modulation could confer P. lilacinum high levels of target enzymes and could lead to the constant withdrawal of antifungals, which would force an increase in the administration of antifungal medications to achieve fungal morbidity or mortality. The findings in this work could aid in the decision-making for treatment strategies in cases of P. lilacinum infection.

Factor IX (FIX) is a vitamin K-dependent protein, and it has become a valuable pharmaceutical in the Hemophilia B treatment. We evaluated the potential of recombinant human FIX (rhFIX) expression in 293T and SK-Hep-1 human cell lines. SK-Hep-1-FIX cells produced higher levels of biologically active protein. The growth profile of 293T-FIX cells was not influenced by lentiviral integration number into the cellular genome. SK-Hep-1-FIX cells showed a significantly lower growth rate than SK-Hep-1 cells. γ-carboxylation process is significant to FIX biological activity, thus we performed a expression analysis of genes involved in this process. The 293T gene expression suggests that this cell line could efficiently carboxylate FIX, however only 28% of the total secreted protein is active. SK-Hep-1 cells did not express high amounts of VKORC1 and carboxylase, but this cell line secreted large amounts of active protein. Enrichment of culture medium with Ca +2 and Mg +2 ions did not affect positively rhFIX expression in SK-Hep-1 cells. In 293T cells, the addition of 0.5 mM Ca +2 and 1 mM Mg +2 resulted in higher rhFIX concentration. SK-Hep-1 cell line proved to be very effective in rhFIX production, and it can be used as a novel biotechnological platform for the production of recombinant proteins.

Recombinant coagulation factor VII is a very important and complex protein employed for treatment of hemophiliac patients (hemophilia A/B) who develop inhibitors antibodies to conventional treatments (FVIII and FIX). The rFVII is a glycosylated molecule and circulates in plasma as zymogen of 50 kDa. When activated the molecule is cleaved to 20-30 kDa and has a half-life of about 3 h, needing to be processed fast and efficiently until freeze-drying. Here, we describe a very simple and fast purification sequence for rFVII using affinity FVII Select resin and a dialysis system that can be easily scaled up.

The gamma-carboxylated proteins belong to a family of proteins that depend on vitamin K for normal biosynthesis. The major representative gamma-carboxylated proteins are the coagulation system proteins, for example, factor VII, factor IX, factor X, prothrombin, and proteins C, S, and Z. These molecules have harbored posttranslational modifications, such as glycosylation and gamma-carboxylation, and for this reason they need to be produced in mammalian cell lines. Human cells lines have emerged as the most promising alternative to the production of gamma-carboxylated proteins. In this chapter, the methods to generate human cells as a platform to produce gamma-carboxylated proteins, for example the coagulation factors VII and IX, are presented. From the cell line modification up to the vitamin K adaptation of the produced cells is described in the protocols presented in this chapter.

The gamma-carboxylated proteins belong to a family of proteins that depend on vitamin K for normal biosynthesis. The major representative gamma-carboxylated proteins are the coagulation system proteins, for example, factor VII, factor IX, factor X, prothrombin, and proteins C, S, and Z. These molecules have harbored posttranslational modifications, such as glycosylation and gamma-carboxylation, and for this reason they need to be produced in mammalian cell lines. Human cells lines have emerged as the most promising alternative to the production of gamma-carboxylated proteins. In this chapter, the methods to generate human cells as a platform to produce gamma-carboxylated proteins, for example the coagulation factors VII and IX, are presented. From the cell line modification up to the vitamin K adaptation of the produced cells is described in the protocols presented in this chapter.

Recombinant factor VII (rFVII) is the main therapeutic choice for hemophilia patients who have developed inhibitory antibodies against conventional treatments (FVIII and FIX). Because of the post-translational modifications, rFVII needs to be produced in mammalian cell lines. In this study, for the first time, we have shown efficient rFVII production in HepG2, Sk-Hep-1, and HKB-11 cell lines. Experiments in static conditions for a period of 96 h showed that HepG2-FVII produced the highest amounts of rhFVII, with an average of 1843 ng/mL. Sk-hep-1-FVII cells reached a maximum protein production of 1432 ng/mL and HKB-11-FVII cells reached 1468 ng/mL. Sk-Hep-1-rFVII and HKB-11-rFVII were selected for the first step of scale-up. Over 10 days of spinner flask culture, HKB-11 and SK-Hep-1 cells showed a cumulative production of rFVII of 152 μg and 202.6 μg in 50 mL, respectively. Thus, these human cell lines can be used for an efficient production of recombinant FVII. With more investment in basic research, human cell lines can be optimized for the commercial production of different bio therapeutic proteins.

The industrial production of recombinant proteins preferentially requires the generation of stable cell lines expressing proteins in a quick, relatively facile, and a reproducible manner. Different methods are used to insert exogenous DNA into the host cell, and choosing the appropriate producing cell is of paramount importance for the efficient production and quality of the recombinant protein. This review addresses the advances in recombinant protein production in mammalian cell lines, according to key patents from the last 30 years.

Objective: Nowadays recombinant factor VIII is produced in murine cells including in Chinese hamster ovary (CHO) and baby hamster kidney cells (BHK). Previous studies, using the murine leukemia virus-derived retroviral vector pMFG-FVIII-P140K, modified two recombinant human cell lines, HepG2 and Hek293 to produce recombinant factor VIII. In order to characterize these cells, the present study aimed to analyze the integration pattern of retroviral vector pMFG-FVIII-P140K. Methods: This study used ligation-mediated polymerase chain reaction to locate the site of viral vector integration by sequencing polymerase chain reaction products. The sequences were compared to genomic databases to characterize respective clones. Results: The retroviral vector presented different and non-random profiles of integration between cells lines. A preference of integration for chromosomes 19, 17 and 11 was observed for HepG2FVIIIdB/P140K and chromosome 9 for Hek293FVIIIdB/P140K. In genomic regions such as CpG islands and transcription factor binding sites, there was no difference in the integration profiles for both cell lines. Integration in intronic regions of encoding protein genes (RefSeq genes) was also observed in both cell lines. Twenty percent of integrations occurred at fragile sites in the genome of the HepG2 cell line and 17% in Hek293. Conclusion: The results suggest that the cell type can affect the profile of chromosomal integration of the retroviral vector used; these differences may interfere in the level of expression of recombinant proteins. © 2014 Associac ¸ ao Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published

Objective The relationship of multipotent mesenchymal stromal cells (MSC) with pericytes and fibroblasts has not been established thus far, although they share many markers of primitive marrow stromal cells and the osteogenic, adipogenic, and chondrogenic differentiation potentials. Materials and Methods We compared MSCs from adult or fetal tissues, MSC differentiated in vitro, fibroblasts and cultures of retinal pericytes obtained either by separation with anti-CD146 or adhesion. The characterizations included morphological, immunophenotypic, gene-expression profile, and differentiation potential. Results Osteogenic, adipocytic, and chondrocytic differentiation was demonstrated for MSC, retinal perivascular cells, and fibroblasts. Cell morphology and the phenotypes defined by 22 markers were very similar. Analysis of the global gene expression obtained by serial analysis of gene expression for 17 libraries and by reverse transcription polymerase chain reaction of 39 selected genes from 31 different cell cultures, revealed similarities among MSC, retinal perivascular cells, and hepatic stellate cells. Despite this overall similarity, there was a heterogeneous expression of genes related to angiogenesis, in MSC derived from veins, artery, perivascular cells, and fibroblasts. Evaluation of typical pericyte and MSC transcripts, such as NG2, CD146, CD271, and CD140B on CD146 selected perivascular cells and MSC by real-time polymerase chain reaction confirm the relationship between these two cell types. Furthermore, the inverse correlation between fibroblast-specific protein-1 and CD146 transcripts observed on pericytes, MSC, and fibroblasts highlight their potential use as markers of this differentiation pathway. Conclusion Our results indicate that human MSC and pericytes are similar cells located in the wall of the vasculature, where they function as cell sources for repair and tissue maintenance, whereas fibroblasts are more differentiated cells with more restricted differentiation potential.

O Fator VII recombinante (FVIIr) tem sido a principal escolha terapêutica dos pacientes hemofílicos que desenvolvem inibidores contra os fatores VIII e IX utilizados como tratamento. Atualmente, o produto utilizado é produzido em células de camundongo (BHK-21), o qual oferece desvantagens considerando a complexidade das modificações pós-traducionais desta proteína e a inserção de glicosilações de origem murina altamente imunogênicas aos seres humanos. Dessa maneira a produção de proteínas para uso terapêutico em linhagens celulares humanas surge como uma alternativa promissora. Dentro desse contexto, o objetivo principal deste trabalho foi clonar e expressar o FVII de coagulação sanguínea em 3 linhagens celulares humanas (HepG2, Sk-Hep, HKB-11), compará-las com a linhagem murina BKH-21, e selecionar a melhor produtora da proteína recombinante. As células foram modificadas com o vetor lentiviral p1054-CIGWS, contendo os genes do FVII e do marcador GFP. Após a modificação das células foi observada uma eficiência de transdução de 80% nas células BHK-21-FVIIr, 73% nas células HepG2-FVIIr, 32% nas células HKB-11-FVIIr e 95% Sk-Hep-FVIIr. Análises da expressão gênica por PCR em Tempo Real mostraram que as três linhagens humanas modificadas apresentaram expressão do RNAm relativo ao FVIIr, sendo que a linhagem celular HepG2 foi a que teve maior expressão de FVIIr, seguida da Sk-Hep-1 e HKB-11. Quando submetidas ao tratamento com vitamina K por um período de 10 dias em cultura, a expressão do gene FVIIr foi semelhante para as três linhagens (HepG2: 164563 URE, HKB-11: 119122 URE e Sk-Hep: 124919 URE). O FVII é uma proteína que para sua ativação, possui como principal modificação pós traducional a -carboxilação vitamina K dependente, que ocorre por meio do ciclo da vitamina K com a participação de 3 enzimas, -carboxilase, VKORC1 e calumenina (inibidor). A expressão gênica dessas enzimas foi avaliada antes e após o tratamento com a vitamina K. Foi possível observar que houve um aumento nos níveis de RNAm nas células humanas tratadas com vitamina K, sugerindo que esta é capaz de ativar as enzimas do ciclo da -carboxilação. A cinética de crescimento celular em garrafas estáticas mostrou que a as células murinas BHK-21 modificadas possuem uma velocidade específica de crescimento 25% mais elevada que das células humanas. Contudo a cinética de produção das linhagens recombinantes mostrou que as células humanas produzem cerca de 3 vezes mais FVIIr do as células BHK-21. Devida a baixa produção de FVIIr na linhagem celular murina, e ao fato de que a linhagem humana HepG2 apresenta um perfil de crescimento extremamente lento, as linhagens recombinantes Sk-Hep-1-FVIIr e HKB-11-FVIIr foram selecionadas para ensaios de cultivo em suspensão utilizando microcarregadores em frascos spinners. Ao longo de 10 dias de cultivo as células HKB-11-FVIIr mostraram uma produção acumulada de 152 g de FVIIr, o que corresponde a 304 UI. As células Sk-Hep-1-FVIIr produziram cerca de 202,6 g de FVIIr, o que corresponde a 405,2 UI. Em suma, nossos dados comprovam que as linhagens celulares humanas são eficazes para a produção de fator VII recombinante, uma vez que, utilizando nosso modelo de produção, estas mostraram-se melhores do que a de células murinas (BHK-21) utilizadas pela indústria. Assim, estas linhagens celulares humanas podem ser usadas como uma nova plataforma para a produção de FVII, bem como para outras proteínas recombinantes, de maneira mais segura e com menor risco de desenvolvimento de anticorpos inibidores Recombinant factor VII (FVIIr) has been the main therapeutic choice for hemophilic patients who develop inhibitors antibidies to conventional treatments (FVIII and FIX). Currently, the comercial product is produced in murine cells (BHK-21) which gives disadvantages considering the complexity of post-translational modifications of these proteins. The insertion of murine residues can be highly immunogenic in humans. Thus the production of proteins for therapeutic use in human cell lines appears as a promising alternative. In this context, the aim of this study was to clone and express the blood coagulation FVII in 3 human cell lines (HepG2, Sk-Hep-1, HKB-11) and select the best cell line for production of recombinant protein. The cells were modified with the lentiviral vector p1054-CIGWS containing the FVII gene and GFP gene marker. After cells modification we observed efficiency of transduction, in which 80% of BHK-21-FVIIr cells showed GFP expression, 73% of HepG2-FVIIr cells, 32% of HKB-11-FVIIr cells and 95% SK- Hep-FVIIr. Gene expression analysis by real-time PCR showed that the three modified human cell lines exhibited RNAm expression relative to FVIIr. When cells were treated with 5 ug/mL vitamin K in culture, the gene expression of FVIIr was similar in the three cell lines (HepG2: 164 563 URE, HKB-11: 119122 and SK-Hep URE: 124919 URE). For FVII activation, the main post translational modification is -carboxylation vitamin-K-dependent which envolves three enzymes, -carboxylase, VKORC1 and calumenina (inhibitor) . Gene expression of these enzymes was evaluated before and after treatment with vitamin K. It was observed that there was an increase in mRNA levels in human cells treated with vitamin K, suggesting that the treatment is capable of activating the enzymes of the vitamin K cycle. Cell growth kinetics showed that modified murine cells BHK-21 have a higher specific growth rate, around 25% more than human cells. However the kinetics of production of recombinant cell lines showed that human cells expressing rFVII 3-fold more rFVII than BHK-21 cells. Due the low rFVII production of murine cells, and the extremely slow growth profile of human cell line HepG2, the recombinant cell lines Sk-Hep-1-rFVII and HKB-11-rFVII have been selected for cultivation tests in suspension using microcarriers in spinners flasks. Over 10 days of cultivation the HKB-11 cells showed a cumulative production of rFVII 152 ug, corresponding to 304 IU and SK-Hep-1 cells showed a rFVII production of 202.6 ug, corresponding to 405.2 IU. In summary, our data demonstrate that human cell lines are effective for producing recombinant factor VII. Using our production model, human cells were better than murine cells (BHK-21) used by the industry. Thus, these human cell lines can be used as a new platform for the FVII production, as well as for other recombinant proteins, with less risk of developing inhibitor antibodies

Ligation-mediated-PCR was performed followed by the mapping of 177 and 150 integration sites from HepG2 and Hek293 transduced with chimera vector carrying recombinant human Factor IX (rhFIX) cDNA, respectively. The sequences were analyzed for chromosome preference, CpG, transcription start site (TSS), repetitive elements, fragile sites and target genes. In HepG2, rhFIX was had an increased preference for chromosomes 6 and 17; the median distance to the nearest CpG islands was 15,240 base pairs and 37 % of the integrations occurred in RefSeq genes. In Hek293, rhFIX had an increased preference for chromosome 5; the median distance to the nearest CpG islands was 209,100 base pairs and 74 % of the integrations occurred in RefSeq genes. The integrations in both cell lines were distant from the TSS. The integration patterns associated with this vector are different in each cell line.

The most important properties of a protein are determined by its primary structure, its amino acid sequence. However, protein features can be also modified by a large number of posttranslational modifications. These modifications can occur during or after the synthesis process, and glycosylation appears as the most common posttranslational modification. It is estimated that 50% of human proteins have some kind of glycosylation, which has a key role in maintaining the structure, stability, and function of the protein. Besides, glycostructures can also influence the pharmacokinetics and immunogenicity of the protein. Although the glycosylation process is a conserved mechanism that occurs in yeast, plants, and animals, several studies have demonstrated significant differences in the glycosylation pattern in recombinant proteins expressed in mammalian, yeast, and insect cells. Thus, currently, important efforts are being done to improve the systems for the expression of recombinant glycosylated proteins. Among the different mammalian cell lines used for the production of recombinant proteins, a significant difference in the glycosylation pattern that can alter the production and/or activity of the protein exists. In this context, human cell lines have emerged as a new alternative for the production of human therapeutic proteins, since they are able to produce recombinant proteins with posttranslational modifications similar to its natural counterpart and reduce potential immunogenic reactions against nonhuman epitopes. This chapter describes the steps necessary to produce a recombinant glycoprotein in a human cell line in small scale and also in bioreactors.

The most important properties of a protein are determined by its primary structure, its amino acid sequence. However, protein features can be also modified by a large number of posttranslational modifications. These modifications can occur during or after the synthesis process, and glycosylation appears as the most common posttranslational modification. It is estimated that 50% of human proteins have some kind of glycosylation, which has a key role in maintaining the structure, stability, and function of the protein. Besides, glycostructures can also influence the pharmacokinetics and immunogenicity of the protein. Although the glycosylation process is a conserved mechanism that occurs in yeast, plants, and animals, several studies have demonstrated significant differences in the glycosylation pattern in recombinant proteins expressed in mammalian, yeast, and insect cells. Thus, currently, important efforts are being done to improve the systems for the expression of recombinant glycosylated proteins. Among the different mammalian cell lines used for the production of recombinant proteins, a significant difference in the glycosylation pattern that can alter the production and/or activity of the protein exists. In this context, human cell lines have emerged as a new alternative for the production of human therapeutic proteins, since they are able to produce recombinant proteins with posttranslational modifications similar to its natural counterpart and reduce potential immunogenic reactions against nonhuman epitopes. This chapter describes the steps necessary to produce a recombinant glycoprotein in a human cell line in small scale and also in bioreactors.

The LX-2 cell line has characteristics of hepatic stellate cells (HSCs), which are considered pericytes of the hepatic microcirculatory system. Recent studies have suggested that HSCs might have mesenchymal origin. We have performed an extensive characterization of the LX-2 cells and have compared their features with those of mesenchymal cells. Our data show that LX-2 cells have a phenotype resembling activated HSCs as well as bone marrow-derived mesenchymal stem cells (BM-MSCs). Our immunophenotypic analysis showed that LX-2 cells are positive for activated HSC markers (αSMA, GFAP, nestin and CD271) and classical mesenchymal makers (CD105, CD44, CD29, CD13, CD90, HLA class-I, CD73, CD49e, CD166 and CD146) but negative for the endothelial marker CD31 and endothelial progenitor cell marker CD133 as well as hematopoietic markers (CD45 and CD34). LX-2 cells also express the same transcripts found in immortalized and primary BM-MSCs (vimentin, annexin 5, collagen 1A, NG2 and CD140b), although at different levels. We show that LX-2 cells are capable to differentiate into multilineage mesenchymal cells in vitro and can stimulate new blood vessel formation in vivo. LX-2 cells appear not to possess tumorigenic potential. Thus, the LX-2 cell line behaves as a multipotent cell line with similarity to BM-MSCs. This line should be useful for further studies to elucidate liver regeneration mechanisms and be the foundation for development of hepatic cell-based therapies.

A hemofilia A é uma doença caracterizada pela deficiência do fator VIII (FVIII) de coagulação sanguínea e atinge 1 em 5000 homens. Países desenvolvidos, utilizam como terapia o FVIII recombinante (rFVIII), por apresentar maior segurança e consistir uma fonte ilimitada. Estudos realizados em nosso laboratório, utilizando o vetor retroviral pMFG-FVIII-P140K, originaram as linhagens celulares humanas, HepG2FVIIIdB/P140K (hepática) e Hek293FVIIIdB/P140K (renal), que foram selecionadas pelo mesmo sistema de seleção, o tratamento in vitro com as drogas Benzilguanina e Temozolomide. O presente trabalho teve por objetivo caracterizar e detalhar o padrão de integração do vetor retroviral pMFG-FVIII-P140K nas duas linhagens celulares humanas, e verificar se o perfil de integração está relacionado ao tipo celular específico ou se este sofre influência da estratégia de seleção a qual as células foram submetidas anteriormente. Foi utilizada a técnica de LM-PCR (ligação-mediada por PCR) que permite localizar o sítio de integração do vetor viral, por meio do sequênciamento do produto de PCR obtido após a digestão com enzimas de restrição e ligação de uma sequência adaptadora (LINKER) ao DNA genômico. Após o seqüenciamento as sequências foram submetidas a análises em bancos de dados de genomas (Human BLAT, QuickMap e DAVID/EASE) para caracterização dos respectivos clones. Também foi realizada uma análise da expressão relativa do mRNA relativo ao rFVIII por RT-PCR e da atividade biológica pelo teste de TTPA. Dessa forma foi possível observar que ambas as linhagens modificadas expressam o mRNA relativo ao rFVIII e que as células HepG2 e Hek293 apresentam níveis de secreção da proteína recombinante biologicamente ativa da ordem de 7,9 UI/mL e 2,1 UI/mL, respectivamente. Foram sequenciados um total de 201 clones da HepG2, sendo 123 similares ao genoma humano e dentre estes 73 considerados verdadeiros e 50 ambíguos. Da Hek293 foram sequenciados 221 clones, sendo 179 similares ao genoma humano e dentre estes 64 verdadeiros e 115 ambíguos. Observamos que o vetor retroviral pMFG-FVIII-P140K apresenta um perfil de integração não randômico e diferente entre as células estudadas, uma vez que na linhagem HepG2 houve uma preferência pelos cromossomos 19, 17 e 11, e na Hek293 pelo cromossomo 9. Em relação a regiões genômicas tais como distância de ilhas CpGs e de sítios de ligação de fatores de transcrição não houve diferença no perfil de integração em ambas as linhagens celulares, visto que nas duas células o vetor se inseriu preferencialmente a uma distância de ± 30-60Kb dessas regiões. Observamos também que houve uma integração dentro de genes codificadores de proteínas da ordem de 52% e 44% nas células HepG2 e Hek293, respectivamente, contudo em ambos os casos mais de 90% dessas inserções ocorreram em regiões intrônicas. Houve 20% de integrações em sítios frágeis do genoma na linhagem HepG2 e 17% na Hek293. Em suma este trabalho mostrou a integração do vetor retroviral pMFG-FVIII-P140K específica para as duas linhagens em estudo. Além disso, pudemos observar que em ambas as linhagens celulares, HepG2FVIIIdB/P140K e Hek293FVIIIdB/P140K, existem regiões gênicas dentro dos cromossomos na qual o vetor exibe uma preferência. O perfil de integração caracterizado aqui difere de outros trabalhos da literatura que utilizaram retrovírus derivados de MLV. Isso nos leva a crer que o padrão de inserção descrito pode estar relacionado ao fato de que essas células foram tratadas anteriormente com drogas quimioterapêuticas para seleção de um clone celular com maior nível de produção de rFVIII, levando consequentemente a seleção de um perfil de integração semelhante entre as linhagens celulares, mesmo estas tendo origens teciduais diferentes. Hemophilia A is a disease characterized by deficiency of blood clotting factor VIII (FVIII) and affects 1 in 5000 men. Developed countries use as therapy for Hemophilia A recombinant FVIII (rFVIII) because rFVIII concentrates have proven efficacy and safety and this therapy consist of an unlimited supply.. Studies in our laboratory using the retroviral vector pMFG-FVIII-P140K, originate the human recombinant cell lines, HepG2FVIIIdB/P140K (liver origen) and Hek293FVIIIdB/P140K (renal origen) which were selected with high doses of Benzyladenine and Temozolomide. This study aimed to characterize the integration pattern of retroviral vector pMFG-FVIII-P140K in these human cell lines, and verify if the profile of integration is related to specific cell type or it was influenced by the selection strategy which cells have been previously submitted. We used the technique of LM-PCR (ligation-mediated PCR) that allows to locate the site of viral vector integration by the sequencing of PCR products. The sequences were obtained after genomic DNA digestion with restriction enzymes and subsequent connection of an adapter (LINKER) to 5or 3 of the DNA fragment. The sequences were analyzed in genomic databases (Human BLAT, and Quickmap DAVID / EASE) for characterization of the respective clones. It was also performed an analysis of relative expression of rFVIII mRNA by RT-PCR and the biological activity was measured by APTT test. Thus it was observed that both cell lines express the mRNA relative to rFVIII and HepG2 and HEK293 cells have levels biologically active recombinant protein approximately 7.9 IU / mL and 2.1 IU / mL, respectively . We sequenced a total of 201 clones of HepG2FVIIIdB/P140K, 123 of these sequences match to the human genome and, among those 73 were considered true and 50 were ambiguous. In Hek293FVIIIdB/P140K 221 clones were sequenced, these total, 179 were similar to the human genome. 64 were true and 115 were ambiguous. We note that the retroviral vector pMFG-FVIII-P140K presents a profile of integration different and non-random between the studied cells lines, in HepG2FVIIIdB/P140K was observed a preference of integration for chromosomes 19, 17 and 11, and in Hek293FVIIIdB/P140K for the chromosome 9. In genomic regions such as CpG islands and transcription factors binding sites (TFBS), there was no difference in the profile of integration in both cell lines. In the two cell lines the vector is inserted preferably at a distance of ± 30 - 60Kb of these regions. We also observed that there was 52% of integration within genes encoding proteins (RefSeq genes) in HepG2FVIIIdB/P140K and 44% in Hek293FVIIIdB/P140K cells. In both cases more than 90% of the insertions occurred in intronic regions. There were 20% of integrations at fragile sites in the genome of HepG2 cell line and 17% in Hek293. In summary this study showed the integration profile of retroviral vector pMFG -FVIII-P140K in two different cell lines that produces FVIIIr protein are very similar. Furthermore, we observed that in both cell lines, HepG2FVIIIdB/P140K and Hek293FVIIIdB/P140K, there are genetic regions within the chromosomes in which the vector displays a preference. The integration profile featured described here differs in CpGs island and TFBS from other studies in the literature that used retroviruses derived from MLV. This leads us to believe that the integration pattern described here may be related to the fact that these cells were previously treated with chemotherapeutic drugs for selecting a cell clone with the highest level of production of rFVIII, consequently leading to selection of a similar profile integration between cell lines, even those having different tissue origins.

A doença falciforme é caracterizada pela presença intra-eritrocitária de Hemoglobina S, um tetrâmero composto de cadeias globina beta (?) mutadas (?S), em que o aminoácido ácido glutâmico é substituído por uma valina. Tal modificação faz com que ocorra a formação de um polímero de HbS que interage com a membrana eritrocitária e deforma as hemácias quando a pressão de oxigênio é reduzida, processo esse conhecido como falcização e que provoca crises vaso-oclusivas no capilar venoso. Tal obstrução dos vasos sanguíneos produzem episódios de dor, anemia hemolítica, lesões em órgãos e mortalidade precoce. As transfusões sanguíneas crônicas em indivíduos com doença falciforme melhoram a qualidade de vida, diminuem os sintomas da anemia, reduzem a quantidade de HbS circulante e melhoram da capacidade de oxigenação. Porém, uma complicação reconhecida da transfusão é a aloimunização contra antígenos eritrocitários, que pode levar à reação transfusional hemolítica. A fenotipagem profilática é o método de prevenção contra a aloimunização em pacientes com doença falciforme, no entanto, essas estratégias não são tão eficazes uma vez que estudos mostraram que aloimunizações contra antígenos dos sistemas Rh e Kell continuam ocorrendo em pacientes com doença falciforme, apesar das transfusões terem sido realizadas com fenótipo compatível. Esse estudo genotipou os antígenos Rh (C/c e E/e) e Kell (K/k) de 77 pacientes com doença falciforme e comparou esses resultados ao fenótipo eritrocitário. A taxa de aloimunização foi de 36,4% e os anticorpos identificados foram, principalmente, contra o sistema Rh (55,17%); o anti-Kell foi encontrado em somente 5 pacientes (8,62%). Foram observadas 17 discrepâncias entre genótipo e fenótipo. Como resultado dessas avaliações, foi confeccionada uma carteirinha contendo as informações do fenótipo deduzido do genótipo para que os pacientes levem em seus atendimentos fora da rede pública do Distrito Federal e que auxiliará na escolha do hemocomponente compatível Sickle cell disease is characterized by the presence of intra-erythrocyte hemoglobin S, a tetramer composed of mutated (?S) beta globin (?) chains, in which the glutamic acid is replaced by a valine. This modification causes \'the formation of an HbS polymer that interacts with the erythrocyte membrane and deforms the red blood cells when the oxygen pressure is reduced. This process is known as sickling and it causes vaso-occlusive crises in the venous capillary. The obstruction of the blood vessels produces episodes of pain, hemolytic anemia, organs damage and early mortality. Chronic blood transfusions in individuals with sickle cell disease improve quality of life, decrease the symptoms of anemia, reduce the amount of circulating HbS and improve oxygenation capacity. Nevertheless, a recognized complication of transfusion is the alloimmunization against erythrocyte antigens, which may lead to hemolytic transfusion reaction. Prophylactic phenotyping is the method of prevention against alloimmunization in patients with sickle cell disease. However, these strategies are not effective since studies have shown that alloimmunizations against antigens of the Rh and Kell systems continue to occur in patients with sickle cell disease, despite transfusions were performed with compatible phenotype. This study genotyped the Rh (C/c and E/e) and Kell (K/k) antigens of 77 sickle cell disease patients and these results were compared to the erythrocyte phenotype. The alloimmunization rate was 36.4% and the specificity of the antibodies identified was mainly against the Rh system (55.17%); anti-Kell was found in only 5 patients (8.62%). There were 17 discrepancies between genotype and phenotype. As a result of these evaluations, a personal card containing information about the phenotype deduced from the genotype was made in order to be taken by the patients to their appointments at the public health network outside Federal District. Furthermore, this personal card will assist in the choice of compatible blood component

Vetores lentivirais são ferramentas fundamentais para modificação celular. Sua utilização ganhou destaque devido à capacidade desses em integrar ao genoma de células que estão ou não em divisão. Grande parte dos vetores desenvolvidos são derivados do genoma do Vírus da Imunodeficiência Humana (HIV-1), portanto, modificações foram necessárias a fim de evitar a formação de Partículas Competentes em Replicação (RCLs) e garantir uma utilização segura. Com as modificações, foram produzidos os vetores lentivirais de terceira geração utilizados atualmente. Esses vetores podem ser usados para expressão constitutiva de genes, produção de proteínas recombinantes, produção de animais transgênicos e terapia gênica. Com isso, torna-se necessário o desenvolvimento de vetores lentivirais para aplicação em pesquisa básica e ensaios clínicos. Dessa forma, o presente estudo teve por objetivo a construção de vetores de expressão lentivirais aplicáveis à: 1- expressão constitutiva de genes de interesse e 2-vetores com promotores específicos para expressão de proteínas em megacariócitos. Esse trabalho descreve a construção desses vetores, sua importância e discute suas possíveis aplicações. As sequências selecionadas para produção dos vetores foram: os genes Runx1C e VkorC1 e os promotores proPF4 e proITGA2b. Todas as sequências encontram-se clonadas em vetor de clonagem e estoques de bactérias com esses vetores congeladas em glicerol foram confeccionados. Para a confecção dos vetores lentivirais, o gene Runx1C foi subclonado no vetor lentiviral base p1054-CIGWS sob controle do promotor forte CMV, enquanto o promotor proITGA2b foi subclonado no vetor base p1054-FVIII, em substituição ao promotor CMV, de forma a controlar a expressão de FVIII. Os dois vetores produzidos apresentam ainda o gene para proteína verde GFP precedida do sítio de ligação do ribossomo IRES, com expressão controlada pelo mesmo promotor interno do vetor. O trabalho possibilitou, portanto, a produção de dois vetores lentivirais bi-cistrônicos: p1054-Runx1C e pL-proITGA2b-FVIII. A construção p1054-Runx1C ainda não foi sequenciada, mas foi confirmada por restrição enzimática e apresenta potencial para aplicação em estudos de diferenciação hematopoética. Já a construção pL-proITGA2b-FVIII foi sequenciada, porém sem confirmação da região de ligação do proITGA2b ao vetor. Reações de PCR e de restrição enzimática confirmaram a ligação e sequenciamento mostrou 67% de similaridade entre a região sequenciada e o promotor ITGA2b depositado no banco de dados. Análise funcional foi realizada através da transfecção desse vetor em células HEK-293T. As células transfectadas apresentaram expressão positiva para GFP e secreção de FVIII no sobrenadante celular, evidenciando que o promotor proITGA2b clonado no vetor encontra-se ativo. Esse vetor apresenta potencial para aplicação em terapia gênica para hemofilias, pois apresenta expressão do fator de coagulação direcionado a megacariócitos e plaquetas, células que estão diretamente relacionadas ao processo de coagulação, representando grandes veículos para secreção desses fatores. Ainda, os dois vetores lentivirais gerados apresentam segurança e eficiência elevadas, pois são vetores de terceira geração auto-inativantes (SIN) e apresentam elementos regulatórios que melhoram o transporte e integração do DNA ao genoma hospedeiro. Lentiviral vectors are fundamental tools for cell modification that gained prominence due to their ability to integrate the genome of non-dividing cells. Most of developed lentiviral vectors are derived from the genome of Human Immunodeficiency Virus (HIV-1), so modifications were necessary in order to avoid the formation of Competent Replication Particles (RCLs) and ensure safer operations. The modifications led to development of third generation lentiviral vectors currently used. These vectors can be used for constitutive gene expression, production of recombinant protein, production of transgenic animals and gene therapy. It\'s evident the need to develop lentiviral vectors for application in basic research and clinical trials. Thus this study aimed to construct lentiviral expression vectors applicable to: 1- constitutive expression of genes of interest and 2-vectors with specific promoters for expression of proteins in megakaryocytes and platelets. This paper describes the construction of these vectors, their importance and discuss their possible applications. Sequences were selected for production of the vectors: genes Runx1C and VkorC1 and proPF4 and proITGA2b promoters. All four sequences are cloned into cloning vectors and stocks of bacteria with these vectors frozen in glycerol were prepared. Lentiviral vectors were engineered from subcloning the sequence Runx1C into the basic lentiviral vector p1054- CIGWS under control of the strong CMV promoter, and from subcloning proITGA2b promoter into p1054-FVIII basic vector, replacing the CMV promoter in order to control the expression of FVIII. Both vectors exhibit the green fluorescence protein GFP gene preceded by a ribosome binding site IRES under control of vector\'s internal promoter. Therefore, this work resulted in the production of two bi-cistronic lentiviral vectors: p1054-Runx1C and pLproITGA2b-FVIII. The p1054-Runx1C construction has not yet been sequenced, but it was confirmed by digestion and has potential for use in hematopoietic differentiation studies. Though, pL-proITGA2b-FVIII construct was sequenced, but the technique didn\'t allow to confirm the binding region between proITGA2b and the vector. Although PCR reaction and digestion confirmed the construction. Sequence analysis showed 67% similarity between the sequenced region and ITGA2b promoter deposited in the database. Functional analysis was performed by transfection of this vector in HEK-293T cells. The transfected cells showed positive expression of GFP and FVIII secretion in cell supernatant, indicating that the proITGA2b promoter cloned into the vector is active. This vector has potential usage in gene therapy for hemophilia, since it can be used to express coagulation factors in megakaryocytes and platelets and these cells are directly related to the clotting process, representing great vehicles for secretion of these factors. Even more, the two lentiviral vectors generated have higher safety and efficiency, as they are self-inactivating (SIN) third-generation vectors and have regulatory elements that enhance transport and integration of DNA into the host genome.