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de Jesus BAP, Echeverri LMS, Magalhães MDLB, Silva GFD. Generation and characterization of avian IgY antibodies for detecting beta-casein A1 in bovine milk. Anal Biochem 2023; 678:115283. [PMID: 37572840 DOI: 10.1016/j.ab.2023.115283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 04/07/2023] [Revised: 07/25/2023] [Accepted: 08/09/2023] [Indexed: 08/14/2023]
Abstract
Beta-casein is a primary milk protein that constitutes approximately 30% of the casein in bovine milk, with the two most common types in cattle being A1 and A2. The A2 protein differs from the A1 version due to a mutation in the codon at position 67, resulting in a histidine to proline substitution. However, the bioactive peptide, beta-casomorphine-7 (BCM7), which originates from partial proteolysis of the A1 variant, has been linked to several gastrointestinal disorders in humans. Production of A1 beta casein-free products is increasing demand in the milk market, worldwide. This study generated and characterized a polyclonal IgY antibody that specifically recognizes the A1 beta-casein protein present in cow's milk. A commercially available IgY anti-A1 antibody was used as a positive control, and the sensitivity and specificity of both the commercial and produced anti-A1 antibodies were evaluated. The results showed 100% sensitivity and specificity of 100% of the commercial IgY anti-A1. The in-house produced anti-A1 antibody demonstrated a sensitivity of 95.2% and a specificity of 100%, indicating its potential as a reliable and cost effective tool for detecting A1 beta-casein protein in milk samples.
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Pereira de Jesus BA, Gomes AA, Clark AE, Rodrigues TA, Ledgerwood-Lee M, Van Zant W, Brickner H, Wang M, Blum DL, Cassera MB, Carlin AF, Aronoff-Spencer ES, da Silva GF, Magalhães MDLB, Ray P. In Vitro Diagnostic Assay to Detect SARS-CoV-2-Neutralizing Antibody in Patient Sera Using Engineered ACE-2 Mini-Protein. Viruses 2022; 14:2823. [PMID: 36560827 PMCID: PMC9780992 DOI: 10.3390/v14122823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 12/13/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022] Open
Abstract
The recent development and mass administration of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) vaccines allowed for disease control, reducing hospitalizations and mortality. Most of these vaccines target the SARS-CoV-2 Spike (S) protein antigens, culminating with the production of neutralizing antibodies (NAbs) that disrupt the attachment of the virus to ACE2 receptors on the host cells. However, several studies demonstrated that the NAbs typically rise within a few weeks after vaccination but quickly reduce months later. Thus, multiple booster administration is recommended, leading to vaccination hesitancy in many populations. Detecting serum anti-SARS-CoV-2 NAbs can instruct patients and healthcare providers on correct booster strategies. Several in vitro diagnostics kits are available; however, their high cost impairs the mass NAbs diagnostic testing. Recently, we engineered an ACE2 mimetic that interacts with the Receptor Binding Domain (RBD) of the SARS-2 S protein. Here we present the use of this engineered mini-protein (p-deface2 mut) to develop a detection assay to measure NAbs in patient sera using a competitive ELISA assay. Serum samples from twenty-one patients were tested. Nine samples (42.8%) tested positive, and twelve (57.1%) tested negative for neutralizing sera. The data correlated with the result from the standard commercial assay that uses human ACE2 protein. This confirmed that p-deface2 mut could replace human ACE2 in ELISA assays. Using bacterially expressed p-deface2 mut protein is cost-effective and may allow mass SARS-CoV-2 NAbs detection, especially in low-income countries where economical diagnostic testing is crucial. Such information will help providers decide when a booster is required, reducing risks of reinfection and preventing the administration before it is medically necessary.
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Affiliation(s)
| | - Anderson Albino Gomes
- Biochemistry Laboratory, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages 88520-000, Brazil
| | - Alex E. Clark
- Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego, CA 92093, USA
| | | | - Melissa Ledgerwood-Lee
- Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego, CA 92093, USA
| | - Westley Van Zant
- Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego, CA 92093, USA
| | - Howard Brickner
- Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego, CA 92093, USA
| | - Meiqiao Wang
- Bioexpression and Fermentation Facility, University of Georgia, Athens, GA 30602, USA
| | - David L. Blum
- Bioexpression and Fermentation Facility, University of Georgia, Athens, GA 30602, USA
| | - Maria B. Cassera
- Department of Biochemistry and Molecular Biology and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, USA
| | - Aaron F. Carlin
- Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego, CA 92093, USA
- Department of Pathology, University of California, San Diego, CA 92093, USA
| | - Eliah S. Aronoff-Spencer
- Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego, CA 92093, USA
| | - Gustavo Felippe da Silva
- Biochemistry Laboratory, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages 88520-000, Brazil
| | | | - Partha Ray
- Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego, CA 92093, USA
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Ramos AF, Fernandes LA, Batista F, de Souza Vieira B, Thompson M, Mattos JJ, Marques MRF, de Lourdes Borba Magalhães M, da Silva GF. TRIM21 chimeric protein as a new molecular tool for multispecies IgG detection. J Genet Eng Biotechnol 2022; 20:111. [PMID: 35900674 PMCID: PMC9334459 DOI: 10.1186/s43141-022-00396-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 01/19/2022] [Accepted: 07/04/2022] [Indexed: 11/30/2022]
Abstract
Background The production of monoclonal antibodies for immunoglobulin detection is not cost-effective, while polyclonal antibody production depends on laboratory animals, raising concerns on animal welfare. The widespread use of immunoglobulins in the pharmaceutical industry and the increasing number and variety of new antibodies entering the market require new detection and purification strategies. The Tripartite motif-containing protein 21 is a soluble intracellular immunoglobulin G receptor that binds to the constant region of immunoglobulin G from various species with high affinity. We hypothesized that using this protein as an antibody-binding module to create immunoglobulin detection probes will improve the portfolio of antibody affinity ligands for diagnostic or therapeutic purposes. Results We created a chimeric protein containing a mutated form of the C-terminal domain of mouse Tripartite motif-containing protein 21 linked to streptavidin to detect immunoglobulin G from various species of mammals. The protein is produced by heterologous expression and consists of an improved molecular tool, expanding the portfolio of antibody-affinity ligands for immunoassays. We also demonstrate that this affinity ligand may be used for purification purposes since imidazole elution of antibodies can be achieved instead of acidic elution conditions of current antibody purification methods. Conclusion Data reported here provides an additional and superior alternative to the use of secondary antibodies, expanding the portfolio of antibodies affinity ligands for detection and purification purposes. Supplementary Information The online version contains supplementary material available at 10.1186/s43141-022-00396-3.
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Affiliation(s)
- Anelize Felicio Ramos
- Biochemistry Laboratory, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil
| | - Leonardo Antônio Fernandes
- Biochemistry Laboratory, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil
| | - Franciane Batista
- Biochemistry Laboratory, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil
| | | | - Mayerson Thompson
- Research and Development Department, Bioclin®, Belo Horizonte, MG, 31.565-130, Brazil
| | - Jacó Joaquim Mattos
- Biochemistry Laboratory, Federal University of Santa Catarina, Florianopolis, Santa Catarina, Brazil
| | | | - Maria de Lourdes Borba Magalhães
- Biochemistry Laboratory, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil.
| | - Gustavo Felippe da Silva
- Biochemistry Laboratory, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil.
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Fernandes LA, Gomes AA, Guimarães BG, de Lourdes Borba Magalhães M, Ray P, da Silva GF. Engineering defensin α‐helix to produce high‐affinity
SARS‐CoV
‐2 spike protein binding ligands. Protein Sci 2022; 31:e4355. [PMID: 35634778 PMCID: PMC9144876 DOI: 10.1002/pro.4355] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 05/05/2022] [Accepted: 05/10/2022] [Indexed: 11/06/2022]
Abstract
The binding of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) spike protein to the angiotensin‐converting enzyme 2 (ACE2) receptor expressed on the host cells is a critical initial step for viral infection. This interaction is blocked through competitive inhibition by soluble ACE2 protein. Therefore, developing high‐affinity and cost‐effective ACE2 mimetic ligands that disrupt this protein–protein interaction is a promising strategy for viral diagnostics and therapy. We employed human and plant defensins, a class of small (2–5 kDa) and highly stable proteins containing solvent‐exposed alpha‐helix, conformationally constrained by two disulfide bonds. Therefore, we engineered the amino acid residues on the constrained alpha‐helix of defensins to mimic the critical residues on the ACE2 helix 1 that interact with the SARS‐CoV‐2 spike protein. The engineered proteins (h‐deface2, p‐deface2, and p‐deface2‐MUT) were soluble and purified to homogeneity with a high yield from a bacterial expression system. The proteins demonstrated exceptional thermostability (Tm 70.7°C), high‐affinity binding to the spike protein with apparent Kd values of 54.4 ± 11.3, 33.5 ± 8.2, and 14.4 ± 3.5 nM for h‐deface2, p‐deface2, and p‐deface2‐MUT, respectively, and were used in a diagnostic assay that detected SARS‐CoV‐2 neutralizing antibodies. This work addresses the challenge of developing helical ACE2 mimetics by demonstrating that defensins provide promising scaffolds to engineer alpha‐helices in a constrained form for designing of high‐affinity ligands.
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Affiliation(s)
- Leonardo Antônio Fernandes
- Biochemistry Laboratory, Center of Agroveterinary Sciences State University of Santa Catarina Lages Santa Catarina Brazil
| | - Anderson Albino Gomes
- Biochemistry Laboratory, Center of Agroveterinary Sciences State University of Santa Catarina Lages Santa Catarina Brazil
| | - Beatriz Gomes Guimarães
- Laboratory of Structural Biology and Protein Engineering Instituto Carlos Chagas ‐ ICC/FIOCRUZ Curitiba‐PR Brazil
| | | | - Partha Ray
- Division of Surgical Oncology, Department of Surgery, Moores Cancer Center University of California – San Diego Health La Jolla California USA
| | - Gustavo Felippe da Silva
- Biochemistry Laboratory, Center of Agroveterinary Sciences State University of Santa Catarina Lages Santa Catarina Brazil
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Teixeira Essenfelder L, Gomes AA, Coimbra JLM, Moreira MA, Ferraz SM, Miquelluti DJ, Felippe da Silva G, Magalhães MDLB. Salivary β-glucosidase as a direct factor influencing the occurrence of halitosis. Biochem Biophys Rep 2021; 26:100965. [PMID: 33732903 PMCID: PMC7941027 DOI: 10.1016/j.bbrep.2021.100965] [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] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 02/19/2021] [Accepted: 02/22/2021] [Indexed: 12/03/2022] Open
Abstract
β-Glucosidases are enzymes present in all living organisms, playing a pivotal role in diverse biological processes. These enzymes cleave β-glycosidic bonds between carbohydrates, or between a carbohydrate and a non-carbohydrate moiety, which may result in the liberation of volatile aglycones. Released compounds execute diverse physiological roles, while the industry takes advantage of exogenously added β-glucosidases for aroma enrichment during food and beverage production. β-Glucosidase enzymatic activity has been reported in human saliva and given the fact that these enzymes are involved in aroma release, we investigated here the correlation between β-glucosidase activity in human saliva and the occurrence of halitosis. Measurement of salivary enzyme activity of 48 volunteers was performed using p-nitrophenyl-β-d-glucopyranoside as substrate. Each volunteer was clinically evaluated by a dental surgeon and clinical and laboratorial data were statistically analyzed. Gas-chromatography of saliva headspace allowed the analysis of the direct role of exogenous β-glucosidase on aromatic /volatile profile of saliva samples. The data demonstrated a positive correlation between halitosis and enzymatic activity, suggesting that the enzyme exerts a direct role in the occurrence of bad breath. Gas-chromatography analysis demonstrated that exogenously added enzyme led to the alteration of volatile organic content, confirming a direct contribution of β-glucosidase activity on saliva volatile compounds release. Although halitosis is a multifactorial condition, the complete understanding of all governing factors may allow the development of more effective treatment strategies. Such studies may pave the way to the use of β-glucosidase inhibitors for halitosis clinical management. β-Glucosidases are capable of altering the aromatic profile of saliva. Increased salivary β-glucosidase is associated with halitosis. Increased salivary β-glucosidase is associated with dental biofilm. Salivary β-glucosidases are produced by oral microrganisms.
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Affiliation(s)
- Lucimari Teixeira Essenfelder
- Biochemistry Laboratory, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil
| | - Anderson Albino Gomes
- Biochemistry Laboratory, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil
| | - Jefferson Luis Meirelles Coimbra
- Department of Soil and Natural Resources, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil
| | - Marcelo Alves Moreira
- Department of Soil and Natural Resources, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil
| | - Sandra Maria Ferraz
- Department of Veterinary Medicine, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil
| | - David José Miquelluti
- Department of Soil and Natural Resources, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil
| | - Gustavo Felippe da Silva
- Biochemistry Laboratory, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil
| | - Maria de Lourdes Borba Magalhães
- Biochemistry Laboratory, Center of Agroveterinary Sciences, State University of Santa Catarina, Lages, Santa Catarina, 88520-000, Brazil
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Costa DD, Gomes AA, Fernandes M, Lopes da Costa Bortoluzzi R, Magalhães MDLB, Skoronski E. Using natural biomass microorganisms for drinking water denitrification. J Environ Manage 2018; 217:520-530. [PMID: 29631241 DOI: 10.1016/j.jenvman.2018.03.120] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Revised: 03/15/2018] [Accepted: 03/27/2018] [Indexed: 06/08/2023]
Abstract
Among the methods that are studied to eliminate nitrate from drinking water, biological denitrification is an attractive strategy. Although several studies report the use of denitrifying bacteria for nitrate removal, they usually involve the use of sewage sludge as biomass to obtain the microbiota. In the present study, denitrifying bacteria was isolated from bamboo, and variable parameters were controlled focusing on optimal bacterial performance followed by physicochemical analysis of water adequacy. In this way, bamboo was used as a source of denitrifying microorganisms, using either Immobilized Microorganisms (IM) or Suspended Microorganisms (SM) for nitrate removal. Denitrification parameters optimization was carried out by analysis of denitrification at different pH values, temperature, nitrate concentrations, carbon sources as well as different C/N ratios. In addition, operational stability and denitrification kinetics were evaluated. Microorganisms present in the biomass responsible for denitrification were identified as Proteus mirabilis. The denitrified water was submitted to physicochemical treatment such as coagulation and flocculation to adjust to the parameters of color and turbidity to drinking water standards. Denitrification using IM occurred with 73% efficiency in the absence of an external carbon source. The use of SM provided superior denitrification efficiency using ethanol (96.46%), glucose (98.58%) or glycerol (98.5%) as carbon source. The evaluation of the operational stability allowed 12 cycles of biomass reuse using the IM and 9 cycles using the SM. After physical-chemical treatment, only SM denitrified water remained within drinking water standards parameters of color and turbidity.
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Affiliation(s)
- Darleila Damasceno Costa
- Universidade do Estado de Santa Catarina, Departamento de Engenharia Ambiental, Laboratório de Tratamento de Água e Resíduos, Av. Luís de Camões, 2090, CEP 88520-000, Lages, Santa Catarina, Brazil
| | - Anderson Albino Gomes
- Universidade do Estado de Santa Catarina, Departamento de Engenharia Ambiental, Laboratório de Tratamento de Água e Resíduos, Av. Luís de Camões, 2090, CEP 88520-000, Lages, Santa Catarina, Brazil
| | - Mylena Fernandes
- Universidade Federal de Santa Catarina, Departamento de Engenharia Química e Engenharia de Alimentos, Laboratório de Engenharia Bioquímica, Campus Universitário Trindade, CEP 88040-900, Florianópolis, Santa Catarina, Brazil
| | - Roseli Lopes da Costa Bortoluzzi
- Universidade do Estado de Santa Catarina, Departamento de Engenharia Florestal, Herbário Lages da Universidade do Estado de Santa Catarina, Av. Luís de Camões, 2090, CEP 88520-000, Lages, Santa Catarina, Brazil
| | - Maria de Lourdes Borba Magalhães
- Universidade do Estado de Santa Catarina, Departamento de Produção Animal e Alimentos, Laboratório de Tecnologia Enzimática, Av. Luís de Camões, 2090, CEP 88520-000, Lages, Santa Catarina, Brazil
| | - Everton Skoronski
- Universidade do Estado de Santa Catarina, Departamento de Engenharia Ambiental, Laboratório de Tratamento de Água e Resíduos, Av. Luís de Camões, 2090, CEP 88520-000, Lages, Santa Catarina, Brazil.
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Albino Gomes A, Pazinatto Telli E, Miletti LC, Skoronski E, Gomes Ghislandi M, Felippe da Silva G, Borba Magalhães MDL. Improved enzymatic performance of graphene-immobilized β-glucosidase A in the presence of glucose-6-phosphate. Biotechnol Appl Biochem 2017. [DOI: 10.1002/bab.1569] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Anderson Albino Gomes
- Department of Food and Animal Science; Center of Agroveterinary Sciences; State University of Santa Catarina; Lages Brazil
- Department of Environmental Engineering; Center of Agroveterinary Sciences; State University of Santa Catarina; Lages Brazil
| | - Elisa Pazinatto Telli
- Department of Food and Animal Science; Center of Agroveterinary Sciences; State University of Santa Catarina; Lages Brazil
| | - Luiz Claudio Miletti
- Department of Food and Animal Science; Center of Agroveterinary Sciences; State University of Santa Catarina; Lages Brazil
| | - Everton Skoronski
- Department of Environmental Engineering; Center of Agroveterinary Sciences; State University of Santa Catarina; Lages Brazil
| | - Marcos Gomes Ghislandi
- Department of Materials Engineering; Academic Unit at Cabo de Santo Agostinho; Rural Federal University of Pernambuco; Cabo de Santo Agostinho Brazil
| | - Gustavo Felippe da Silva
- Department of Forest Engineering; Center of Agroveterinary Sciences; State University of Santa Catarina; Lages Brazil
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Moraes JC, França M, Sartor AA, Bellato V, de Moura AB, Magalhães MDLB, de Souza AP, Miletti LC. Prevalence ofEimeriaspp. in Broilers by Multiplex PCR in the Southern Region of Brazil on Two Hundred and Fifty Farms. Avian Dis 2015; 59:277-81. [DOI: 10.1637/10989-112014-reg] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Wilner SE, Wengerter B, Maier K, de Lourdes Borba Magalhães M, Del Amo DS, Pai S, Opazo F, Rizzoli SO, Yan A, Levy M. An RNA alternative to human transferrin: a new tool for targeting human cells. Mol Ther Nucleic Acids 2012; 1:e21. [PMID: 23344001 PMCID: PMC3390244 DOI: 10.1038/mtna.2012.14] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The transferrin receptor, CD71, is an attractive target for drug development because of its high expression on a number of cancer cell lines and the blood brain barrier. To generate serum-stabilized aptamers that recognize the human transferrin receptor, we have modified the traditional aptamer selection protocol by employing a functional selection step that enriches for RNA molecules which bind the target receptor and are internalized by cells. Selected aptamers were specific for the human receptor, rapidly endocytosed by cells and shared a common core structure. A minimized variant was found to compete with the natural ligand, transferrin, for receptor binding and cell uptake, but performed ~twofold better than it in competition experiments. Using this molecule, we generated aptamer-targeted siRNA-laden liposomes. Aptamer targeting enhanced both uptake and target gene knockdown in cells grown in culture when compared to nonmodified or nontargeted liposomes. The aptamer should prove useful as a surrogate for transferrin in many applications including cell imaging and targeted drug delivery.
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Affiliation(s)
- Samantha E Wilner
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York, USA
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