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León-Félix CM, Maranhão AQ, Amorim CA, Lucci CM. Optimizing Decellularization of Bovine Ovarian Tissue: Toward a Transplantable Artificial Ovary Scaffold with Minimized Residual Toxicity and Preserved Extracellular Matrix Morphology. Cells Tissues Organs 2024:000537838. [PMID: 38359805 DOI: 10.1159/000537838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 02/09/2024] [Indexed: 02/17/2024] Open
Abstract
INTRODUCTION The decellularized extracellular matrix (dECM) from ovarian tissue could be the best scaffold for the development of a transplantable artificial ovary. Typically, dECM from ovarian tissue has been obtained using sodium dodecyl sulfate (SDS), at a concentration of 1% for 24 h. However, SDS can leave residues in the tissue, which may be toxic to the seeded cells. This study aimed to obtain dECM from bovine ovarian tissue using SDS and NaOH at a minimum concentration in the shortest incubation time. METHODS The respective SDS and NaOH concentrations investigated were 1% and 0.2M; 0.5% and 0.1M; 0.1% and 0.02M, and 0.05% and 0.01M, with 24, 12, and 6 h incubation periods. After the incubation time the tissue was washed in 50 mL of distilled water for 6 h. RESULTS Histological analysis confirmed decellularization and showed the conservation of collagen fibers in all samples following treatment. Furthermore, the lowest SDS and NaOH concentrations that showed no DNA remaining during electrophoresis analysis were 0.1% and 0.02M when incubated for 24 and 12 h. DNA quantification resulted in ˂ 0.2 ng DNA/mg ovarian tissue using these protocols. Additionally, the coculture of dECM (obtained by 0.1% SDS and 0.02M NaOH for 12 h) with ovarian cells showed that there was no toxic effect for the cells for up to 72 h. CONCLUSION The protocol involving 0.1% SDS and 0.02M NaOH for 12 h incubation decellularizes bovine ovarian tissue, generating a dECM that preserves the native ECM morphology and is non-toxic to ovarian cells.
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McManus C, Neves AAB, Diniz Filho JA, Maranhão AQ, Souza Filho AG. Profiles not metrics: the case of Brazilian universities. AN ACAD BRAS CIENC 2021; 93:e29290261. [PMID: 34495201 DOI: 10.1590/0001-3765202120200261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 05/21/2020] [Indexed: 11/21/2022] Open
Abstract
Public universities, and science in general, in Brazil, are under attack from key persons of the government in interviews and articles published in non-scientific journals. Here we look at bibliography data from international science metric platforms (Scival® and Incites®) and official Brazilian agencies such as CAPES and CNPq to reach some conclusions based on scientific analysis. Brazilian Science has shown a steady improvement in quantity and quality over the last 20 years but has recently suffered (since 2015) under severe financial restrictions. An increase in international collaboration also increased citation impact, reaching almost five times the world average. While the medical and natural sciences show the highest impact and prominence, social sciences and the humanities also have spotlight areas with international excellence. Different research institutions and universities offer a variety of production profiles and impacts. This diagnosis shows the need for universities and research institutes in Brazil and funding agencies to undergo strategic planning for definition of mission/vision, goals to be reached, and areas for priority development. Continued support of public universities by the government is necessary for Brazilian autonomy in science and technology and its full integration in the world scientific community.
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Affiliation(s)
- Concepta McManus
- Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Ciências Fisiológicas, Campus Darcy Ribeiro, Asa Norte, 70910-900 Brasília, DF, Brazil
| | - Abilio A Baeta Neves
- Cátedra Paschoal Senise, Pró-Reitoria de Pós-Graduação, Universidade de São Paulo, Rua da Reitoria, 374, 4º andar, Cidade Universitária, 05508-220 São Paulo, SP, Brazil
| | - José Alexandre Diniz Filho
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Departamento de Ecologia & Evolução, Avenida Esperança, s/n, Campus Samambaia, 74690-900 Goiânia, GO, Brazil
| | - Andrea Q Maranhão
- Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Biologia Celular, Campus Darcy Ribeiro, Asa Norte, 70910-900 Brasília, DF, Brazil
| | - Antonio G Souza Filho
- Universidade Federal de Ceará, Centro de Ciências, Departamento de Física, Campus do Pici, Bloco 922, 60440-900 Fortaleza, CE, Brazil
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Abstract
CAR-T cell therapy emerged in the last years as a great promise to cancer treatment. Nowadays, there is a run to improve the breadth of its use, and thus, new chimeric antigen receptors (CAR) are being proposed. The antigen-binding counterpart of CAR is an antibody fragment, scFv (single chain variable fragment), that recognizes a membrane protein associated to a cancer cell. In this chapter, the use of human scFv phage display libraries as a source of new mAbs against surface antigen is discussed. Protocols focusing in the use of extracellular domains of surface protein in biotinylated format are proposed as selection antigen. Elution with unlabeled peptide and selection in solution is described. The analysis of enriched scFvs throughout the selection using NGS is also outlined. Taken together these protocols allow for the isolation of new scFvs able to be useful in the construction of new chimeric antigen receptors for application in cancer therapy.
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Affiliation(s)
- Nestor F Leyton-Castro
- Molecular Pathology Graduation Programme, School of Medicine, University of Brasilia, Brasilia, Brazil
| | - Marcelo M Brigido
- Molecular Pathology Graduation Programme, School of Medicine, University of Brasilia, Brasilia, Brazil
- Department of Cell Biology, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil
| | - Andrea Q Maranhão
- Molecular Pathology Graduation Programme, School of Medicine, University of Brasilia, Brasilia, Brazil.
- Department of Cell Biology, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil.
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Luz D, Shiga EA, Chen G, Quintilio W, Andrade FB, Maranhão AQ, Caetano BA, Mitsunari T, Silva MA, Rocha LB, Moro AM, Sidhu SS, Piazza RMF. Structural Changes in Stx1 Engineering Monoclonal Antibody Improves Its Functionality as Diagnostic Tool for a Rapid Latex Agglutination Test. Antibodies (Basel) 2018; 7:antib7010009. [PMID: 31544861 PMCID: PMC6698835 DOI: 10.3390/antib7010009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 01/10/2018] [Accepted: 01/26/2018] [Indexed: 11/16/2022] Open
Abstract
Stx1 toxin is one of the AB5 toxins of Shiga toxin-producing Escherichia coli (STEC) responsible for foodborne intoxication during outbreaks. The single-chain variable fragment (scFv) is the most common recombinant antibody format; it consists of both variable chains connected by a peptide linker with conserved specificity and affinity for antigen. The drawbacks of scFv production in bacteria are the heterologous expression, conformation and stability of the molecule, which could change the affinity for the antigen. In this work, we obtained a stable and functional scFv-Stx1 in bacteria, starting from IgG produced by hybridoma cells. After structural modifications, i.e., change in protein orientation, vector and linker, its solubility for expression in bacteria was increased as well as the affinity for its antigen, demonstrated by a scFv dissociation constant (KD) of 2.26 × 10-7 M. Also, it was able to recognize purified Stx1 and cross-reacted with Stx2 toxin by ELISA (Enzyme-Linked Immunosorbent Assay), and detected 88% of Stx1-producing strains using a rapid latex agglutination test. Thus, the scFv fragment obtained in the present work is a bacteria-produced tool for use in a rapid diagnosis test, providing an alternative for STEC diagnosis.
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Affiliation(s)
- Daniela Luz
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
| | - Emerson A Shiga
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
| | - Gang Chen
- Department of Molecular Genetics, Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada.
| | - Wagner Quintilio
- Laboratório de Biofármacos em Células Animais, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
| | - Fernanda B Andrade
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
| | - Andrea Q Maranhão
- Laboratório de Imunologia, Universidade de Brasília, Brasília 70910-900, Brazil.
| | - Bruna A Caetano
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
| | - Thaís Mitsunari
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
| | - Míriam A Silva
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
| | - Letícia B Rocha
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
| | - Ana M Moro
- Laboratório de Biofármacos em Células Animais, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
| | - Sachdev S Sidhu
- Department of Molecular Genetics, Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada.
| | - Roxane M F Piazza
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
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de Almeida JRF, Santiago KL, Kaihami GH, Maranhão AQ, de Macedo Brígido M, de Almeida SR. The Efficacy of Humanized Antibody against the Sporothrix Antigen, gp70, in Promoting Phagocytosis and Reducing Disease Burden. Front Microbiol 2017; 8:345. [PMID: 28316596 PMCID: PMC5334357 DOI: 10.3389/fmicb.2017.00345] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 02/20/2017] [Indexed: 01/18/2023] Open
Abstract
Sporotrichosis is a subcutaneous mycosis distributed worldwide and is frequently reported in countries with tropical climates, as Latin America countries. We previously demonstrated that mice with sporotrichosis produce specific antibodies against a 70-kDa fungal protein, indicating that specific antibodies against this molecule may help to control the sporotrichosis. IgG1 monoclonal antibody was generated, and called mAbP6E7, in mice against a 70-kDa glycoprotein (gp70) of S. schenckii. The mAbP6E7 showed prophylactic and therapeutic activity against sporotrichosis. However, this antibody has a murine origin, and this can generate an immune response when administered to humans, precluding its use for a prolonged time. For its possible use in the treatment of human sporotrichosis, we humanized the mAbP6E7 by genetic engineering. Once expressed, the humanized antibodies had good stability and were able to bind to the 70-kDa cell wall antigens of Sporothrix schenckii and S. brasiliensis. The humanized P6E7 were able to opsonize S. schenckii yeasts, thus increasing the phagocytic index in human monocyte-derived macrophages. The treatment with humanized P6E7 decreased fungal burden in vivo. These data suggest that humanized P6E7 may have a therapeutic role in sporotrichosis.
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Affiliation(s)
- José R F de Almeida
- Department of Clinical and Toxicological Analysis, Faculty of Pharmaceutical Sciences, University of São Paulo São Paulo, Brazil
| | - Karla L Santiago
- Department of Clinical and Toxicological Analysis, Faculty of Pharmaceutical Sciences, University of São Paulo São Paulo, Brazil
| | - Gilberto H Kaihami
- Department of Biochemistry, Institute of Chemistry, University of São Paulo São Paulo, Brazil
| | - Andrea Q Maranhão
- Department of Cell Biology, Institute of Biological Sciences, University of Brasilia Brasilia, Brazil
| | - Marcelo de Macedo Brígido
- Department of Cell Biology, Institute of Biological Sciences, University of Brasilia Brasilia, Brazil
| | - Sandro R de Almeida
- Department of Clinical and Toxicological Analysis, Faculty of Pharmaceutical Sciences, University of São Paulo São Paulo, Brazil
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Luz D, Chen G, Maranhão AQ, Rocha LB, Sidhu S, Piazza RMF. Development and characterization of recombinant antibody fragments that recognize and neutralize in vitro Stx2 toxin from Shiga toxin-producing Escherichia coli. PLoS One 2015; 10:e0120481. [PMID: 25790467 PMCID: PMC4366190 DOI: 10.1371/journal.pone.0120481] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 01/22/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Stx toxin is a member of the AB5 family of bacterial toxins: the active A subunit has N-glycosidase activity against 28S rRNA, resulting in inhibition of protein synthesis in eukaryotic cells, and the pentamer ligand B subunits (StxB) bind to globotria(tetra)osylceramide receptors (Gb3/Gb4) on the cell membrane. Shiga toxin-producing Escherichia coli strains (STEC) may produce Stx1 and/or Stx2 and variants. Strains carrying Stx2 are considered more virulent and related to the majority of outbreaks, besides being usually associated with hemolytic uremic syndrome in humans. The development of tools for the detection and/or neutralization of these toxins is a turning point for early diagnosis and therapeutics. Antibodies are an excellent paradigm for the design of high-affinity, protein-based binding reagents used for these purposes. METHODS AND FINDINGS In this work, we developed two recombinant antibodies; scFv fragments from mouse hybridomas and Fab fragments by phage display technology using a human synthetic antibody library. Both fragments showed high binding affinity to Stx2, and they were able to bind specifically to the GKIEFSKYNEDDTF region of the Stx2 B subunit and to neutralize in vitro the cytotoxicity of the toxin up to 80%. Furthermore, the scFv fragments showed 79% sensitivity and 100% specificity in detecting STEC strains by ELISA. CONCLUSION In this work, we developed and characterized two recombinant antibodies against Stx2, as promising tools to be used in diagnosis or therapeutic approaches against STEC, and for the first time, we showed a human monovalent molecule, produced in bacteria, able to neutralize the cytotoxicity of Stx2 in vitro.
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Affiliation(s)
- Daniela Luz
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
| | - Gang Chen
- Banting and Best Department of Medical Research, Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada
| | | | - Leticia B. Rocha
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
| | - Sachdev Sidhu
- Banting and Best Department of Medical Research, Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada
| | - Roxane M. F. Piazza
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
- * E-mail:
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Zepeda AB, Figueroa CA, Abdalla DSP, Maranhão AQ, Ulloa PH, Pessoa A, Farías JG. Biomarkers to evaluate the effects of temperature and methanol on recombinant Pichia pastoris. Braz J Microbiol 2014; 45:475-83. [PMID: 25242930 PMCID: PMC4166271 DOI: 10.1590/s1517-83822014000200014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 09/09/2013] [Indexed: 02/06/2023] Open
Abstract
Pichia pastoris is methylotrophic yeast used as an efficient expression system for heterologous protein production. In order to evaluate the effects of temperature (10 and 30 °C) and methanol (1 and 3% (v/v)) on genetically-modified Pichia pastoris, different biomarkers were evaluated: Heat stress (HSF-1 and Hsp70), oxidative stress (OGG1 and TBARS) and antioxidant (GLR). Three yeast cultures were performed: 3X = 3% methanol-10 °C, 4X = 3% methanol-30 °C, and 5X = 1% methanol-10°C. The expression level of HIF-1α, HSF-1, HSP-70 and HSP-90 biomarkers were measured by Western blot and in situ detection was performed by immunocytochemistry. Ours results show that at 3% methanol −30 °C there is an increase of mitochondrial OGG1 (mtOGG1), Glutathione Reductase (GLR) and TBARS. In addition, there was a cytosolic expression of HSF-1 and HSP-70, which indicates a deprotection against nucleolar fragmentation (apoptosis). On the other hand, at 3% methanol −10 °C and 1% and at methanol −10 °C conditions there was nuclear expression of OGG1, lower levels of TBARS and lower expression of GLR, cytosolic expression of HSF-1 and nuclear expression HSP-70. In conclusion, our results suggest that 3% methanol-30 °C is a condition that induces a strong oxidative stress and risk factors of apoptosis in modified-genetically P. pastoris.
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Affiliation(s)
- Andrea B Zepeda
- Departamento de Ingeniería Química Facultad de Ingeniería, Ciencias y Administración Universidad de La Frontera Temuco Chile Departamento de Ingeniería Química, Facultad de Ingeniería, Ciencias y Administración, Universidad de La Frontera, Temuco, Chile. ; Departamento de Tecnologia Bioquímico-Farmacêutica Faculdade de Ciências Farmacêuticas Universidade de São Paulo São PauloSP Brazil Departamento de Tecnologia Bioquímico-Farmacêutica, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Carolina A Figueroa
- Departamento de Ingeniería Química Facultad de Ingeniería, Ciencias y Administración Universidad de La Frontera Temuco Chile Departamento de Ingeniería Química, Facultad de Ingeniería, Ciencias y Administración, Universidad de La Frontera, Temuco, Chile. ; Departamento de Tecnologia Bioquímico-Farmacêutica Faculdade de Ciências Farmacêuticas Universidade de São Paulo São PauloSP Brazil Departamento de Tecnologia Bioquímico-Farmacêutica, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Dulcineia S P Abdalla
- Departamento de Análises Clínicas e Toxicológicas Faculdade de Ciências Farmacêuticas Universidade de São Paulo São PauloSP Brazil Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Andrea Q Maranhão
- Departamento de Biología Celular Instituto de Ciências Biológicas Universidade de Brasilia BrasíliaDF Brazil Departamento de Biología Celular, Instituto de Ciências Biológicas, Universidade de Brasilia, Brasília, DF, Brazil
| | - Patricio H Ulloa
- Departamento de Ingeniería Química Facultad de Ingeniería, Ciencias y Administración Universidad de La Frontera Temuco Chile Departamento de Ingeniería Química, Facultad de Ingeniería, Ciencias y Administración, Universidad de La Frontera, Temuco, Chile
| | - Adalberto Pessoa
- Departamento de Tecnologia Bioquímico-Farmacêutica Faculdade de Ciências Farmacêuticas Universidade de São Paulo São PauloSP Brazil Departamento de Tecnologia Bioquímico-Farmacêutica, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Jorge G Farías
- Departamento de Ingeniería Química Facultad de Ingeniería, Ciencias y Administración Universidad de La Frontera Temuco Chile Departamento de Ingeniería Química, Facultad de Ingeniería, Ciencias y Administración, Universidad de La Frontera, Temuco, Chile
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Zepeda AB, Figueroa CA, Abdalla DSP, Maranhão AQ, Ulloa PH, Pessoa A, Farías JG. HSF-1, HIF-1 and HSP90 expression on recombinant Pichia pastoris under fed-batch fermentation. Braz J Microbiol 2014; 45:485-90. [PMID: 25242931 PMCID: PMC4166272 DOI: 10.1590/s1517-83822014000200015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 09/09/2013] [Indexed: 11/23/2022] Open
Abstract
Pichia pastoris is a methylotrophic yeast used as an efficient expression system for heterologous protein production as compared to other expression systems. Considering that every cell must respond to environmental changes to survive and differentiate, determination of endogenous protein related to heat stress responses and hypoxia, it would necessary to establish the temperature and methanol concentration conditions for optimal growth. The aim of this study is characterize the culture conditions through the putative biomarkers in different conditions of temperature and methanol concentration. Three yeast cultures were performed: 3X = 3% methanol −10 °C, 4X = 3% methanol −30 °C, and 5X = 1% methanol −10 °C. The expression level of HIF-1α, HSF-1, HSP-70 and HSP-90 biomarkers were measured by Western blot and in situ detection was performed by immunocytochemistry. The western blot results of HIF-1α and HSP-90 did not indicate statistically significant in the culture conditions studied. Respect to biomarkers location, HIF-1α and HSP-90 presented differences between cultures. In conclusion, the results suggest the cultures in a hypoxic condition produce a high density and yeast cells smaller. Beside the high density would not necessary related with a high production of recombinant proteins in modified-genetically P. pastoris.
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Affiliation(s)
- Andrea B Zepeda
- Departamento de Ingeniería Química Facultad de Ingeniería, Ciencias y Administración Universidad de La Frontera Temuco Chile Departamento de Ingeniería Química, Facultad de Ingeniería, Ciencias y Administración, Universidad de La Frontera, Temuco, Chile. ; Departamento de Tecnologia Bioquímico-Farmacêutica Faculdade de Ciências Farmacêuticas Universidade de São Paulo São PauloSP Brazil Departamento de Tecnologia Bioquímico-Farmacêutica, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Carolina A Figueroa
- Departamento de Ingeniería Química Facultad de Ingeniería, Ciencias y Administración Universidad de La Frontera Temuco Chile Departamento de Ingeniería Química, Facultad de Ingeniería, Ciencias y Administración, Universidad de La Frontera, Temuco, Chile. ; Departamento de Tecnologia Bioquímico-Farmacêutica Faculdade de Ciências Farmacêuticas Universidade de São Paulo São PauloSP Brazil Departamento de Tecnologia Bioquímico-Farmacêutica, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Dulcineia S P Abdalla
- Departamento de Análises Clínicas e Toxicológicas Faculdade de Ciências Farmacêuticas Universidade de São Paulo São PauloSP Brazil Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Andrea Q Maranhão
- Departamento de Biología Celular Instituto de Ciências Biológicas Universidade de Brasília BrasíliaDF Brazil Departamento de Biología Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF, Brazil
| | - Patricio H Ulloa
- Departamento de Ingeniería Química Facultad de Ingeniería, Ciencias y Administración Universidad de La Frontera Temuco Chile Departamento de Ingeniería Química, Facultad de Ingeniería, Ciencias y Administración, Universidad de La Frontera, Temuco, Chile
| | - Adalberto Pessoa
- Departamento de Tecnologia Bioquímico-Farmacêutica Faculdade de Ciências Farmacêuticas Universidade de São Paulo São PauloSP Brazil Departamento de Tecnologia Bioquímico-Farmacêutica, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Jorge G Farías
- Departamento de Ingeniería Química Facultad de Ingeniería, Ciencias y Administración Universidad de La Frontera Temuco Chile Departamento de Ingeniería Química, Facultad de Ingeniería, Ciencias y Administración, Universidad de La Frontera, Temuco, Chile
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Caravelli A, Luz DE, Andrade FB, Moraes CTP, Maranhão AQ, Piazza RMF. Sensitive and specific detection of enteropathogenic and enterohemorrhagic Escherichia coli using recombinant anti-intimin antibody by immunofluorescence assay. Diagn Microbiol Infect Dis 2013; 77:301-3. [PMID: 24095642 DOI: 10.1016/j.diagmicrobio.2013.08.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 08/20/2013] [Accepted: 08/23/2013] [Indexed: 01/04/2023]
Abstract
The main and common virulence factor expressed by enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC) is intimin, a 94-kDa outer membrane protein, which is a product of the eae gene, and, thus, an excellent target for the detection of these pathogens. Among the methods for detection of virulence factor expression, immunoassays can be considered the first alternative to either animal use or in vitro culture cells assays, for which polyclonal and/or monoclonal antibodies are raised. In the present work, we evaluated the sensitivity and specificity of an intimin recombinant antibody (scFv-intimin) using immunofluorescence assay. The scFv-intimin detected typical EPEC, atypical EPEC, and EHEC isolates (100% sensitivity) with no detection of eae- isolates (100% specificity). Thus, immunofluorescence is an effective and rapid method, and scFv-intimin, an excellent tool for the diagnosis of diarrhea caused by EPEC and EHEC and also can be employed in case-control epidemiological surveys.
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Quilici LS, Silva-Pereira I, Andrade AC, Albuquerque FC, Brigido MM, Maranhão AQ. A minimal cytomegalovirus intron A variant can improve transgene expression in different mammalian cell lines. Biotechnol Lett 2012; 35:21-7. [PMID: 22955677 DOI: 10.1007/s10529-012-1043-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Accepted: 08/21/2012] [Indexed: 11/28/2022]
Abstract
The expression enhancement by cytomegalovirus promoter and different intron A (IA) variants were evaluated in CHO-K1, HepG2, HEK-293 and COS-7 cells by assessing the levels of luciferase activity. This data along with mRNA levels measurement indicated that the construct harboring an IA variant with a 200-nucleotide deletion (Δ200) had the greatest impact on increasing luciferase expression among all constructs evaluated. Based on these results, we redesigned pCMV-IA variants and cloned them into plasmids expressing a humanized antibody. These plasmids were then used to transfect CHO-K1 cells. Production of the antibody was not augmented with the Δ200 promoter variant. The 600-nucleotide deletion (Δ600) and whole IA promoter variants expressed similar levels of the recombinant protein. These data indicate that the IA-based enhanced expression of transgenes depends on a small region within the intron.
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Affiliation(s)
- L S Quilici
- Instituto de Ciências Biológicas, Departamento de Biologia Celular, Laboratório de Imunologia Molecular, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Brasília, DF, Brazil
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Ferreira KS, Maranhão AQ, Garcia MCC, Brígido MM, Santos SS, Lopes JD, Almeida SR. Dendritic cells transfected with scFv from Mab 7.B12 mimicking original antigen gp43 induces protection against experimental Paracoccidioidomycosis. PLoS One 2011; 6:e15935. [PMID: 21249212 PMCID: PMC3017565 DOI: 10.1371/journal.pone.0015935] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Accepted: 12/02/2010] [Indexed: 11/25/2022] Open
Abstract
Paracoccidioidomycosis (PCM), endemic in Latin America, is a progressive systemic mycosis caused by Paracoccidioides brasiliensis (P. brasiliensis), which primarily attacks lung tissue. Dendritic cells (DCs) are able to initiate a response in naïve T cells, and they also participate in Th-cell education. Furthermore, these cells have been used for therapy in several disease models. Here we transfected DCs with a plasmid (pMAC/PS-scFv) encoding a single chain variable fragment (scFv) of an anti-Id antibody that is capable of mimicking gp43, the main antigenic component of P. brasiliensis. First, Balb/c mice were immunized subcutaneously with pMAC/PS-scFv and, after seven days, scFv protein was presented to the regional lymph nodes cells. Moreover, we showed that the DCs transfected with scFv were capable of efficiently activating proliferation of total lymph node cells and inducing a decrease in lung infection. Therefore, our results suggested that the use of scFv-transfected DCs may be a promising therapy in the paracoccidioidomycosis (PCM) model.
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Affiliation(s)
- Karen S Ferreira
- Departamento de Ciências Biológicas do Instituto de Ciências Ambientais, Químicas e Farmacêuticas da Universidade Federal de São Paulo, São Paulo, Brazil.
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12
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Silva HM, Vieira PMMM, Costa PLN, Pimentel BMS, Moro AM, Kalil J, Maranhão AQ, Coelho V, Brigido MM. Novel humanized anti-CD3 antibodies induce a predominantly immunoregulatory profile in human peripheral blood mononuclear cells. Immunol Lett 2009; 125:129-36. [PMID: 19573559 DOI: 10.1016/j.imlet.2009.06.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2009] [Revised: 06/15/2009] [Accepted: 06/22/2009] [Indexed: 01/12/2023]
Abstract
Strategies to minimize the immunogenicity and toxicity of murine anti-CD3 antibodies (e.g. OKT3) are of special interest for organ transplantation and for the treatment of autoimmune diseases. In the present work, we have developed two humanized anti-CD3 antibodies. These molecules were shown to bind to human CD3, though less efficiently, and display less mitogenic activity than OKT3. These results prompted us to investigate whether this reduced mitogenic potential was associated with the development of anti-inflammatory properties. Indeed, in peripheral blood mononuclear cells (PBMCs), the humanized antibody versions induced a predominantly anti-inflammatory cytokine profile, in contrast with the pro-inflammatory profile induced by OKT3. Neither OKT3 nor the humanized versions induced the expression of IL-4, IL-2 or TGF-beta. Both humanized antibodies induced significantly lower production of IFN-gamma and IL-5 and slightly higher production of IL-10 than OKT3. This immunomodulatory profile was most evident by the 80-fold higher ratio of IL-10/IFN-gamma production in PBMCs cultured in the presence of the humanized antibodies, compared to those stimulated with OKT3. Furthermore, these humanized anti-CD3 antibodies induced a late FOXP3 gene expression while OKT3 led to a more transient expression of FOXP3. Taken our results, we suggest that these humanized anti-CD3 antibodies may promote the development of T cells with immunoregulatory activity.
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Affiliation(s)
- Hernandez M Silva
- Departamento de Biologia Celular, Universidade de Brasília, 70910-900 Brasília, DF, Brazil
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Melo-Silva CR, Maranhão AQ, Nagasse-Sugahara TK, Bisordi I, Suzuki A, Brigido MM. Characterization of hantaviruses circulating in Central Brazil. Infection, Genetics and Evolution 2009; 9:241-7. [DOI: 10.1016/j.meegid.2008.11.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Revised: 11/24/2008] [Accepted: 11/25/2008] [Indexed: 12/16/2022]
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14
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Arraes FB, Carvalho MJAD, Maranhão AQ, Brígido MM, Pedrosa FO, Felipe MSS. Differential metabolism of Mycoplasma species as revealed by their genomes. Genet Mol Biol 2007. [DOI: 10.1590/s1415-47572007000200004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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15
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Andrade RV, Da Silva SP, Torres FAG, Poças-Fonseca MJ, Silva-Pereira I, Maranhão AQ, Campos EG, Moraes LMP, Jesuíno RSA, Pereira M, Soares CMA, Walter MEMT, Carvalho MJA, Almeida NF, Brigido MM, Felipe MSS. Overview and perspectives on the transcriptome of Paracoccidioides brasiliensis. Rev Iberoam Micol 2005; 22:203-12. [PMID: 16499412 DOI: 10.1016/s1130-1406(05)70044-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Paracoccidioides brasiliensis is a dimorphic and thermo-regulated fungus which is the causative agent of paracoccidioidomycosis, an endemic disease widespread in Latin America that affects 10 million individuals. Pathogenicity is assumed to be a consequence of the dimorphic transition from mycelium to yeast cells during human infection. This review shows the results of the P. brasiliensis transcriptome project which generated 6,022 assembled groups from mycelium and yeast phases. Computer analysis using the tools of bioinformatics revealed several aspects from the transcriptome of this pathogen such as: general and differential metabolism in mycelium and yeast cells; cell cycle, DNA replication, repair and recombination; RNA biogenesis apparatus; translation and protein fate machineries; cell wall; hydrolytic enzymes; proteases; GPI-anchored proteins; molecular chaperones; insights into drug resistance and transporters; oxidative stress response and virulence. The present analysis has provided a more comprehensive view of some specific features considered relevant for the understanding of basic and applied knowledge of P. brasiliensis.
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Affiliation(s)
- Rosângela V Andrade
- Laboratorio de Biologia Molecular, Departamento de Biologia Celular, Universidade de Brasília, Brasilia, DF, 70910-900, Brazil
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16
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Felipe MSS, Torres FAG, Maranhão AQ, Silva-Pereira I, Poças-Fonseca MJ, Campos EG, Moraes LMP, Arraes FBM, Carvalho MJA, Andrade RV, Nicola AM, Teixeira MM, Jesuíno RSA, Pereira M, Soares CMA, Brígido MM. Functional genome of the human pathogenic fungus Paracoccidioides brasiliensis. ACTA ACUST UNITED AC 2005; 45:369-81. [PMID: 16061364 DOI: 10.1016/j.femsim.2005.05.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2005] [Accepted: 05/07/2005] [Indexed: 10/25/2022]
Abstract
Paracoccidioides brasiliensis is a dimorphic and thermo-regulated fungus which is the causative agent of paracoccidioidomycosis, an endemic disease widespread in Latin America. Pathogenicity is assumed to be a consequence of the cellular differentiation process that this fungus undergoes from mycelium to yeast cells during human infection. In an effort to elucidate the molecular mechanisms involved in this process a network of Brazilian laboratories carried out a transcriptome project for both cell types. This review focuses on the data analysis yielding a comprehensive view of the fungal metabolism and the molecular adaptations during dimorphism in P. brasiliensis from analysis of 6022 groups, related to expressed genes, which were generated from both mycelium and yeast phases.
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Affiliation(s)
- Maria Sueli S Felipe
- Departamento de Biologia Celular, Laboratório de Biologia Molecular, Instituto de Biologia, Universidade de Brasília.
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17
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Vasconcelos ATR, Ferreira HB, Bizarro CV, Bonatto SL, Carvalho MO, Pinto PM, Almeida DF, Almeida LGP, Almeida R, Alves-Filho L, Assunção EN, Azevedo VAC, Bogo MR, Brigido MM, Brocchi M, Burity HA, Camargo AA, Camargo SS, Carepo MS, Carraro DM, de Mattos Cascardo JC, Castro LA, Cavalcanti G, Chemale G, Collevatti RG, Cunha CW, Dallagiovanna B, Dambrós BP, Dellagostin OA, Falcão C, Fantinatti-Garboggini F, Felipe MSS, Fiorentin L, Franco GR, Freitas NSA, Frías D, Grangeiro TB, Grisard EC, Guimarães CT, Hungria M, Jardim SN, Krieger MA, Laurino JP, Lima LFA, Lopes MI, Loreto ELS, Madeira HMF, Manfio GP, Maranhão AQ, Martinkovics CT, Medeiros SRB, Moreira MAM, Neiva M, Ramalho-Neto CE, Nicolás MF, Oliveira SC, Paixão RFC, Pedrosa FO, Pena SDJ, Pereira M, Pereira-Ferrari L, Piffer I, Pinto LS, Potrich DP, Salim ACM, Santos FR, Schmitt R, Schneider MPC, Schrank A, Schrank IS, Schuck AF, Seuanez HN, Silva DW, Silva R, Silva SC, Soares CMA, Souza KRL, Souza RC, Staats CC, Steffens MBR, Teixeira SMR, Urmenyi TP, Vainstein MH, Zuccherato LW, Simpson AJG, Zaha A. Swine and poultry pathogens: the complete genome sequences of two strains of Mycoplasma hyopneumoniae and a strain of Mycoplasma synoviae. J Bacteriol 2005; 187:5568-77. [PMID: 16077101 PMCID: PMC1196056 DOI: 10.1128/jb.187.16.5568-5577.2005] [Citation(s) in RCA: 221] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2005] [Accepted: 05/19/2005] [Indexed: 11/20/2022] Open
Abstract
This work reports the results of analyses of three complete mycoplasma genomes, a pathogenic (7448) and a nonpathogenic (J) strain of the swine pathogen Mycoplasma hyopneumoniae and a strain of the avian pathogen Mycoplasma synoviae; the genome sizes of the three strains were 920,079 bp, 897,405 bp, and 799,476 bp, respectively. These genomes were compared with other sequenced mycoplasma genomes reported in the literature to examine several aspects of mycoplasma evolution. Strain-specific regions, including integrative and conjugal elements, and genome rearrangements and alterations in adhesin sequences were observed in the M. hyopneumoniae strains, and all of these were potentially related to pathogenicity. Genomic comparisons revealed that reduction in genome size implied loss of redundant metabolic pathways, with maintenance of alternative routes in different species. Horizontal gene transfer was consistently observed between M. synoviae and Mycoplasma gallisepticum. Our analyses indicated a likely transfer event of hemagglutinin-coding DNA sequences from M. gallisepticum to M. synoviae.
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Affiliation(s)
- Ana Tereza R Vasconcelos
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Avenida Bento Gonçalves 9500, Prédio 43421, Porto Alegre, RS, Brazil
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Caldas C, Coelho V, Kalil J, Moro AM, Maranhão AQ, Brígido MM. Humanization of the anti-CD18 antibody 6.7: an unexpected effect of a framework residue in binding to antigen. Mol Immunol 2003; 39:941-52. [PMID: 12695120 DOI: 10.1016/s0161-5890(03)00022-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Humanization of monoclonal antibodies by complementary determinant region (CDR)-grafting has become a standard procedure to improve the clinical usage of animal antibodies. However, antibody humanization may result in loss of activity that has been attributed to structural constraints in the framework structure. In this paper, we report the complete humanization of the 6.7 anti-human CD18 monoclonal antibody in a scFv form. We used a germline-based approach to design a humanized VL gene fragment and expressed it together with a previously described humanized VH. The designed humanized VL has only 14 mutations compared to the closest human germline sequence. The resulting humanized scFv maintained the binding capacity and specificity to human CD18 expressed on the cell surface of peripheral blood mononuclear cells (PBMC), and showed the same pattern of staining T-lymphocytes sub-populations, in comparison to the original monoclonal antibody. We observed an unexpected effect of a conserved mouse-human framework position (L37) that hinders the binding of the humanized scFv to antigen. This paper reveals a new framework residue that interferes with paratope and antigen binding and also reinforces the germline approach as a successful strategy to humanize antibodies.
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Affiliation(s)
- Cristina Caldas
- Departamento de Biologia Celular, Universidade de Brasi;lia, 70910-900, DF, Brasília, Brazil.
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Felipe MSS, Andrade RV, Petrofeza SS, Maranhão AQ, Torres FAG, Albuquerque P, Arraes FBM, Arruda M, Azevedo MO, Baptista AJ, Bataus LAM, Borges CL, Campos EG, Cruz MR, Daher BS, Dantas A, Ferreira MASV, Ghil GV, Jesuino RSA, Kyaw CM, Leitão L, Martins CR, Moraes LMP, Neves EO, Nicola AM, Alves ES, Parente JA, Pereira M, Poças-Fonseca MJ, Resende R, Ribeiro BM, Saldanha RR, Santos SC, Silva-Pereira I, Silva MAS, Silveira E, Simões IC, Soares RBA, Souza DP, De-Souza MT, Andrade EV, Xavier MAS, Veiga HP, Venancio EJ, Carvalho MJA, Oliveira AG, Inoue MK, Almeida NF, Walter MEMT, Soares CMA, Brígido MM. Transcriptome characterization of the dimorphic and pathogenic fungus Paracoccidioides brasiliensis by EST analysis. Yeast 2003; 20:263-71. [PMID: 12557278 DOI: 10.1002/yea.964] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Paracoccidioides brasiliensis is a pathogenic fungus that undergoes a temperature-dependent cell morphology change from mycelium (22 degrees C) to yeast (36 degrees C). It is assumed that this morphological transition correlates with the infection of the human host. Our goal was to identify genes expressed in the mycelium (M) and yeast (Y) forms by EST sequencing in order to generate a partial map of the fungus transcriptome. Individual EST sequences were clustered by the CAP3 program and annotated using Blastx similarity analysis and InterPro Scan. Three different databases, GenBank nr, COG (clusters of orthologous groups) and GO (gene ontology) were used for annotation. A total of 3,938 (Y = 1,654 and M = 2,274) ESTs were sequenced and clustered into 597 contigs and 1,563 singlets, making up a total of 2,160 genes, which possibly represent one-quarter of the complete gene repertoire in P. brasiliensis. From this total, 1,040 were successfully annotated and 894 could be classified in 18 functional COG categories as follows: cellular metabolism (44%); information storage and processing (25%); cellular processes-cell division, posttranslational modifications, among others (19%); and genes of unknown functions (12%). Computer analysis enabled us to identify some genes potentially involved in the dimorphic transition and drug resistance. Furthermore, computer subtraction analysis revealed several genes possibly expressed in stage-specific forms of P. brasiliensis. Further analysis of these genes may provide new insights into the pathology and differentiation of P. brasiliensis.
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Affiliation(s)
- M S S Felipe
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade de Brasília, 70910-900 Brasília, DF, Brasil.
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20
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Abstract
We describe the expression of an anti-Z-DNA single chain variable region antibody fragment (scFv) on a filamentous phage surface. Four vectors for phage display were constructed. Two of them are able to display multiple copies of the antibody fragment, and the others can be used to make monovalent libraries. The vectors use different promoter/leader sequences to direct the expression of the fused proteins. All were able to promote the assembly of fusion virion particles. In this paper we also show the affinity selection (biopanning) of those phage-antibodies based on the capacity of their products to recognize the antigen. We used biotinylated Z-DNA and the selection was performed in a solution phase fashion. The data presented here indicate that these vectors can be further used to construct anti-nucleic acid antibody fragment libraries that can be used to study the basis of nucleic acid-protein interaction and its role in autoimmunity mechanisms.
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Affiliation(s)
- A Q Maranhão
- Departamento de Biologia Celular, Instituto de Biologia, Universidade de Brasília, Brasília, DF, Brasil
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21
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Abstract
The pAC92 plasmid is a direct screening cloning vector which allows positive selection of recombinant clones (re-clones). This new high-copy-number plasmid vector encodes ampicillin resistance and carries the Bacillus subtilis alpha-amylase (alpha-Amy)-encoding gene (amy) containing a multiple cloning site. The pAC92 plasmid confers to Escherichia coli transformants an amylolytic phenotype easily detected by iodine vapor staining. The re-clones are identified by insertional inactivation of alpha-Amy activity. During pAC92 construction, a bacterial growth defect was observed in host cells after some modifications of the promoter region that caused the increase in the amy expression. This suicide characteristic permitted the positive selection of re-clones. A second transformation step was performed to enhance the rate of re-clones per plate.
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Affiliation(s)
- E V Barros
- Laboratory of Molecular Biology, Department of Cellular Biology, University of Brasilia, Brazil
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