ABSTRACT
Background: Gardnerella vaginalis is a bacterial vaginosis (BV)-associated vaginal bacterium that produces the toxin vaginolysin (VLY). VLY is a pore-forming toxin that is suggested to be the main virulence factor of G. vaginalis. The high recurrence rate of BV and the emergence of antibiotic-resistant bacterial species demonstrate the need for the development of recombinant antibodies as novel therapeutic agents for disease treatment. Single-chain variable fragments (scFvs) generated against VLY exhibited reduced efficacy to neutralize VLY activity compared to the respective full-length antibodies. To improve the properties of scFvs, monospecific dimeric scFvs were generated by the genetic fusion of two anti-VLY scFv molecules connected by an alpha-helix-forming peptide linker. Results: N-terminal hexahistidine-tagged dimeric scFvs were constructed and produced in Escherichia coli and purified using metal chelate affinity chromatography. Inhibition of VLY-mediated human erythrocyte lysis by dimeric and monomeric scFvs was detected by in vitro hemolytic assay. The circulating half-life of purified scFvs in the blood plasma of mice was determined by ELISA. Dimeric anti-VLY scFvs showed higher neutralizing potency and extended circulating half-life than parental monomeric scFv. Conclusions: The protein obtained by the genetic fusion of two anti-VLY scFvs into a dimeric molecule exhibited improved properties in comparison with monomeric scFv. This new recombinant antibody might implement new possibilities for the prophylaxis and treatment of the diseases caused by the bacteria G. vaginalis.
Subject(s)
Animals , Mice , Bacterial Proteins/immunology , Bacterial Toxins/immunology , Antibodies, Neutralizing/metabolism , Single-Chain Antibodies/metabolism , Bacterial Proteins/toxicity , Bacterial Toxins/toxicity , Enzyme-Linked Immunosorbent Assay , Gardnerella vaginalis , Vaginosis, Bacterial , Dimerization , Virulence Factors , Gene Fusion , Antibodies, Neutralizing/immunology , Single-Chain Antibodies/immunology , Half-LifeABSTRACT
Monoclonal antibodies represent the fastest growing class of biopharmaceutical products and have a host of applications in medical research, diagnosis, therapy, and basic science. The production of recombinant monoclonal antibodies has revolutionized the generation of immunoglobulins, and their use represents a strategic breakthrough, affecting the global pharmaceutical market for therapeutic proteins. In the present work, a review of scFv, and the number of related patents, has been carried out. The results show that several countries have scFv patents, most notably the United States, China and United Kingdom. The target of these scFv antibodies was also assessed and the results demonstrate that most are directed toward cancer therapy.
Anticorpos monoclonais representam a classe de maior crescimento em produtos de biofármacos e possuem várias aplicações em pesquisa médica, diagnóstico, terapias e ciência básica. A produção de anticorpos monoclonais recombinantes revolucionou a geração de imunoglobulinas e sua utilização implica em avanço estratégico, afetando o mercado farmacêutico global de proteínas terapêuticas. No presente trabalho, uma revisão sobre scFv e a relação do seu número de patentes foi analisada. Os resultados mostram que vários países apresentam patentes de scFv com destaque para os Estados Unidos, China e Reino Unido. Os alvos desses anticorpos também foram avaliados e as análises revelaram que a maioria é destinado a terapias contra o câncer.
Subject(s)
Antigens, Differentiation , Antibodies, Monoclonal/pharmacology , Antibodies, Monoclonal/therapeutic use , Biopharmaceutics/trends , Drug Synergism , Intellectual Property of Pharmaceutic Products and Process , Colony-Stimulating FactorsABSTRACT
Los anticuerpos surgieron en los organismos en respuesta a las necesidades imperantes de neutralizar y destruir los embates de agentes externos nocivos para los mismos. Los anticuerpos son macromoléculas que por sus propiedades de especificidad y afinidad a sus antígenos, han sido utilizados para toda una gama de estudios en la medicina, su manipulación fuera de los sistemas vivientes ha permitido su aplicación en la terapéutica y el diagnóstico oportuno de varias enfermedades. El presente trabajo muestra una sinopsis de las propiedades bioquímicas de los anticuerpos y de las estrategias más recientes que han permitido la manipulación de estas moléculas, con la finalidad de mejorar su afinidad y avidez, así como en los métodos de producción para incrementar su potencial de aplicación en la investigación biológica y médica.
Antibodies appeared in the organisms in response to the needs of neutralizing and destroying the attacks of external agents injurious to themselves. Antibodies are macromolecules that because of their properties of specificity and affinity to their antigens, have been used in a great variety of studies in medicine. Moreover, their manipulation out of living systems has permitted their application in the treatment and opportune diagnosis of several diseases. The present work shows a synopsis of antibodies biochemical properties and the most recent strategies that have allowed the manipulation of these molecules in order to improve their affinity and avidity. This work will also present the methodological advances that can increase antibodies application potential in biology and in medical research.
Subject(s)
Antibodies , Antibodies, Monoclonal , BacteriophagesABSTRACT
Nicotiana tabacum hairy roots that express the antibody 14D9 were established. The 14D9 antibody yield obtained after 20 days of culture was 5.95 μg 14D9ml-1. The addition of the reticulum endoplasmic retention sequence KDEL demonstrated a positive effect over the intracellular 14D9 amounts with a yield increase up to 20.82 µg ml-1. DMSO increased the antibody amount in the biomass from 20.00 to 64.03 µg ml-1 while PVP (at 1.5 gl-1) and gelatine (at 5.0 gl-1) increased total 14D9 amounts in the culture medium to 25 µg and 14 µg respectively.