Papers by Agustin Ostachuk
Scientific Reports, 2021
Development has intrigued humanity since ancient times. Today, the main paradigm in developmental... more Development has intrigued humanity since ancient times. Today, the main paradigm in developmental biology and evolutionary developmental biology (evo-devo) is the genetic program, in which development is explained by the interplay and interaction of genes, that is, by the action of gene regulatory networks (GRNs). However, it is not even clear that a GRN, no matter how complex, can be translated into a form. Therefore, the fundamental enigma of development still remains: how is a complex organism formed from a single cell? This question unfolded the historical drama and the dialectical tension between preformation and epigenesis. In order to shed light on these issues, I studied the development of crabs (infraorder Brachyura), as representative of the subphylum Crustacea, using network theory. The external morphology of the different phases of brachyuran metamorphosis were modeled as networks and their main characteristics analyzed. As one could expect, the parameters usually regarded as indicative of network complexity, such as modularity and hierarchy, increased during development. However, when more sophisticated complexity measures were tested, it was evidenced that whereas a group of complexity measures increased during development, another group decreased. This led to consider that two kinds of complexities were being measured. I called them intensive and extensive complexity. In view of these results, I propose that crab development involves a passage from an intensive to an extensive complexity. In other words, crab development can be interpreted as a process of unfolding of an intensive, preexistent complexity.
Ludus Vitalis, 2020
¿La ciencia ya ha respondido las preguntas fundamentales acerca de los conceptos de vida, cosmos ... more ¿La ciencia ya ha respondido las preguntas fundamentales acerca de los conceptos de vida, cosmos y evolución? ¿Acaso la ciencia no ha relegado estas preguntas fundamentales por el seguimiento de emprendimientos más inmediatos, "útiles" y prácticos, que en última instancia aseguren que la rueda del capitalismo siga girando en su búsqueda frenética del progreso material y económico? Hay algo terriblemente mal en la actual teoría de la evolución, entendida ésta como la teoría darwiniana con sus sucesivas versiones y extensiones. El concepto de selección natural, la piedra angular del darwinismo, es inconsistente lógicamente. Esto ha sido demostrado en algunas de mis últimas publicaciones académicas. Todo el marco conceptual del darwinismo es inadecuado. Los organismos no compiten unos con otros por la supervivencia del más apto. La relación fundamental en la naturaleza no es la competición ni la confrontación, sino la interconectividad, la complementariedad y la significancia relacional. Es necesaria una nueva teoría de la evolución que explique cómo es posible que a partir de organismos tan simples como bacterias, protozoos y diatomeas, se hayan generado organismos tan complejos como los primates y, entre ellos, al ser humano, un ser capaz de sentir y pensar, de sufrir y disfrutar, un ser capaz de tener ideales y propósitos. Una teoría que explique cómo es posible que este ser tan complejo, rico, y hasta cierto punto aún desconocido, haya surgido de una única célula, una célula-huevo, carente de todas las capacidades, riquezas y profundidades de la existencia humana. Una teoría de este tipo ya existe.
Cosmos and History: The Journal of Natural and Social Philosophy, 2020
In this work I propose a theory of evolution as a process of unfolding. This theory is based on f... more In this work I propose a theory of evolution as a process of unfolding. This theory is based on four logically concatenated principles. The principle of evolutionary order establishes that the more complex cannot be generated from the simpler. The principle of origin establishes that there must be a maximum complexity that originates the others by logical deduction. Finally, the principle of unfolding and the principle of actualization guarantee the development of the evolutionary process from the simplest to the most complex. These logical principles determine the existence of a virtual ideological matrix that contains the sequence of the preformed and folded morphogenetic fields. In this manner, the evolutionary process consists of the sequential unfolding and actualization of these fields, which is motorized by a process of teleologization carried out by the opening consciousness of the forms included in the fields of the ideological matrix. This theory leads to a radical change of perspective regarding the materialist worldview, and places life at the center of the evolutionary process as an activity carried out by a consciousness that seeks to fulfill a purpose by actualizing its own potentialities.
Ludus Vitalis, 2019
En este trabajo se abordará la doctrina del organicismo, según fue explicada y vista principalmen... more En este trabajo se abordará la doctrina del organicismo, según fue explicada y vista principalmente por Bertalanffy. Se estudiará cómo esta doctrina representa y encarna la ambigüedad de la teleología kantiana como principio regulativo, y cómo esta misma problemática conduce a considerar un problema real como un problema de conocimiento. Se concluirá que el organicismo, concebido de esta manera, no representa un verdadero holismo, sino lo que llamaremos un sin-holismo, una síntesis o ensamblaje, y que para obtener un verdadero holismo se debe recurrir al concepto de forma verdadera. Por último, se establecerá que dado que la característica fundamental de un organismo es su desarrollo, se requiere una teoría histórica del organismo para la cual el concepto de campo puede ser útil y necesario.
Cosmos and History: The Journal of Natural and Social Philosophy, 2019
The modern concept of ideology was established by the liberal politician and philosopher Destutt ... more The modern concept of ideology was established by the liberal politician and philosopher Destutt de Tracy, with the objective of creating an all-embracing and general science of ideas, which followed the sensualist and empiricist trend initiated by Locke that culminated in the positivism of Comte. Natural selection and immunity are two key concepts in the history of biology that were strongly based on the Malthusian concept of struggle for existence. This concept wrongly assumed that population grew faster than the means of existence. This “natural” law contained implicitly the idea that the poor and least gifted would not survive. This idea led to the progressive development of the concept of natural selection, whose definitive version was given by Darwin. Mechnikov took the concepts of struggle for existence and natural selection and conceived infectious diseases as a struggle between a host and its invader, the so-called phagocytosis theory. This theory created the necessity to possess mechanisms to discriminate between the own and the foreign, and led to the conception of the immune self. These concepts were not developed from ideas coming from perceptions or sensations, but from ideas coming from their values: individual interest, inevitable inequality, property, utility and profit. Values are ideals that constitute an ideological matrix which exerts a numinous activity and influence the development of our future actions. In consequence, science and its practice cannot avoid and ignore the values that drive them and impulse them towards certain directions.
Evolutionary Biology, 2019
Eucaridan evolution involved a process starting from a body organization characterized by an elon... more Eucaridan evolution involved a process starting from a body organization characterized by an elongate and cylindrical cephalothorax, a well-developed abdomen composed of swimming appendages, ending in a tail fan formed by flattened uropods and a telson. This process would lead, ultimately, to a body organization characterized by a shortened and depressed cephalothorax, and a reduced and ventrally folded abdomen. This ultimate process is typically known as carcinization, and is commonly defined as the process of becoming a crab. In this work, the evolution of the superorder Eucarida was studied using complex networks. A new definition of crab and carcinization are given based on the results obtained. A crab is a topological structural closure that determines the formation of a triadic central core. The evolution of the crab implied the formation of a triadic structure with high closeness centrality, formed by the cephalon, the fused thoracomere 1-4 and the carapace, which represented a highly stable hierarchical core deeply buried or enclosed in the topological structure of the network, responsible for the generation of a highly integrated and robust topology. Under this new definition, the representative of the infraorder Anomura used in this work, which is commonly considered as a crab, is not. This network seemed to be characterized by the presence of a quasi-dyadic structure, formed by the cephalon and the carapace, which was not sufficient for generating the topological closure.
Ludus Vitalis, 2018
La vida es el centro de nuestra existencia. Uno estaría tentado a afirmar que ante todo vivimos. ... more La vida es el centro de nuestra existencia. Uno estaría tentado a afirmar que ante todo vivimos. Sin embargo, nuestra existencia no parece transcurrir en esa modalidad. El materialismo exacerbado en el que transcurre nuestra existencia, desplaza a la vida del centro de la escena. Nuestra sociedad está organizada en torno a la producción, el consumismo, la explotación, la eficientización, el comercio y la propaganda. Es decir, nuestra existencia parece tener como centro de organización de nuestras actividades a la economía. La lucha de este siglo que comienza es poner a la vida en el centro de nuestra existencia, y poner a la economía en el lugar que le corresponde, es decir, al servicio de la vida.
Cosmos and History: The Journal of Natural and Social Philosophy, 2018
This is an epistemologically-driven history of the concept of evolution. Starting from its incept... more This is an epistemologically-driven history of the concept of evolution. Starting from its inception, this work will follow the development of this pregnant concept. However, in contradistinction to previous attempts, the objective will not be the identification of the different meanings it adopted through history, but conversely, it will let the concept to be unfolded, to be explicated and to express its own inner potentialities. The underlying thesis of the present work is, therefore, that the path that leads to the development of the concept of evolution is the path that studies the possibilities of the evolution of concepts, and that the historical reconstruction of its conceptual trajectory will shed light into potential and unexploited possibilities. This methodology will provide useful tools and resources for future developments of the concept. For example, it will define the concept of transmutation as a different conceptual trajectory deviating from the one corresponding to evolution, at the onset of the 19th century. Moreover, epigenesis will not be the opposing concept to evolution, but only to simultaneous and instantaneous generation. It will demonstrate that every important system of epigenesis drew upon some kind of formative power to explain development. More importantly, it will show that the problem of preformation cannot be overlooked, and that some kind of virtual preformation must be considered in order to address the problems of generation and development.
Ludus Vitalis, 2016
¿Es la vida una simple resultante de la conjunción de procesos físico-químicos? ¿Puede reducirse ... more ¿Es la vida una simple resultante de la conjunción de procesos físico-químicos? ¿Puede reducirse a una mera yuxtaposición de sucesos determinados espacialmente? ¿Qué epistemología o forma de ver el mundo nos permite comprenderla? Aristóteles creó un sistema filosófico propio en el que la naturaleza es vista como una totalidad dinámica y en constante movimiento. La vida es una manifestación de ella, y es permitida y gobernada por la psyché. La psyché es el principio organizativo de los distintos niveles biológicos: nutritivo, perceptivo e intelectivo. El experimento crucial de Driesch aportó pruebas empíricas de la existencia de este principio de vida, al que denominó entelequia. La entelequia es una multiplicidad intensiva, y no puede comprenderse con los parámetros usuales derivados de lo extensivo. El ámbito propio de la entelequia es el de la duración. Esta permite la reintroducción del concepto de teleología en la esfera de lo viviente, entendida no como causa final, sino como orden nacida del deseo y conducente a la acción.
Evolutionary Biology, 2016
Darwin proposed natural selection as the main evolutionary mechanism in 1859. However, he did not... more Darwin proposed natural selection as the main evolutionary mechanism in 1859. However, he did not think that this was the only process by which new species were generated. It was the so-called Modern Synthesis who established natural selection as the only mechanism responsible for evolution. Since then, the evolutionary process is explained by the pair mutation-adaptation: new species are generated by the appearance of new mutations, which in case of allowing new adaptations to the environment, they will be fixed and organisms will survive, therefore resulting in new species. An alternative view to the plasticity promoted by the adaptationist program is to think organisms as truly organized structures, having different levels of structural organization, which would mean that not every form is possible, but only those that correspond to a certain building plan. This would be reflected in the appearance of structural constraints, showing the limits imposed to the organism during its evolutionary development. In this work, I studied the ontogeny and development of three species of the genus Trophon by geometric morphometrics, in order to clarify important concepts in evolutionary developmental biology (Evo-Devo). Integrating theoretical and empirical investigations, I could propose a new conceptual framework for heterochrony in a context of a complex theory of recapitulation. Furthermore, I could detect a developmental constraint in Trophon, which provided an opportunity to reconstruct the concept of constraint and propose a synthesis between heterochrony and constraint that explained evolution as a process fueled by them, that is, as directive and driving force.
Archives of Virology, 2016
Bovine viral diarrhea virus (BVDV) is a member of the genus Pestivirus, family Flaviviridae, and ... more Bovine viral diarrhea virus (BVDV) is a member of the genus Pestivirus, family Flaviviridae, and is one of the most widely distributed viruses in cattle worldwide. Approximately 60 % of cattle in endemic areas without control measures are infected with BVDV during their lifetime. This wide prevalence of BVDV in cattle populations results in significant economic losses. BVDV is capable of establishing persistent infections in its host due to its ability to infect fetuses, causing immune tolerance. However, this cannot explain how the virus evades the innate immune system. The objective of the present work was to test the potential activity of E2 as a complement regulatory protein. E2 glycoprotein, produced both in soluble and transmembrane forms in stable CHO-K1 cell lines, was able to reduce complement-mediated cell lysis up to 40 % and complement-mediated DNA fragmentation by 50 %, in comparison with cell lines not expressing the glycoprotein. This work provides the first evidence of E2 as a complement regulatory protein and, thus, the finding of a mechanism of immune evasion by BVDV. Furthermore, it is postulated that E2 acts as a self-associated molecular pattern (SAMP), enabling the virus to avoid being targeted by the immune system and to be recognized as self.
Revista Iberoamericana de Ciencia, Tecnología y Sociedad, 2015
¿Cuál es la relación entre ciencia e ideología?. ¿Son dos cosas incompatibles, complementarias o ... more ¿Cuál es la relación entre ciencia e ideología?. ¿Son dos cosas incompatibles, complementarias o son la misma cosa?. ¿Debe evitar la ciencia dejarse “contaminar” por la ideología?. ¿Hay una única manera de hacer ciencia?. ¿Todas conducen a los mismos resultados y nos dan la misma visión del mundo?. Nos centraremos en la figura de Alexander Bogdanov, médico y filósofo ruso, para debatir sobre estos y otros temas de relevancia actual. Sus teorías dieron origen a lo que después se denominó la “teoría de las dos ciencias”, que da título a este trabajo.
Sociologia em Rede, 2015
What is the relation between science and ideology? Are they incompatible, complementary or the sa... more What is the relation between science and ideology? Are they incompatible, complementary or the same thing? Should science avoid “contamination” from ideology? Is there an only way to do science? Does anyone of them lead to the same results and give us the same worldview? We will focus on the figure of Alexander Bogdanov, Russian physician and philosopher, in order to discuss these and other relevant topics. His theories gave birth to what may be called later “the theory of two sciences”, which entitles this work.
História Ciências Saúde-Manguinhos, 2015
La influencia de Kurt Goldstein en el pensamiento de Georges Canguilhem se extendió a lo largo de... more La influencia de Kurt Goldstein en el pensamiento de Georges Canguilhem se extendió a lo largo de toda su obra. El presente trabajo pretende recuperar esta relación con el objeto de realizar un estudio de la norma como nexo o conexión entre el concepto y la vida. En consecuencia, este trabajo será una reflexión sobre el planteamiento de la vida como actividad normativa y auto-realización. Para ello, será necesario resignificar los conceptos de salud y enfermedad, y atravesar el camino que va de uno a otro. Al final de este camino, se encontrará que estos conceptos permiten explicar la identidad entre el concepto y la vida, lo cual conduce a la conclusión inesperada que la cura es, en definitiva, autocuración.
The influence of Kurt Goldstein on the thinking of Georges Canguilhem extended throughout his entire work. This paper seeks to examine this relationship in order to conduct a study of the norm as a nexus or connection between the concept and life. Consequently, this work will be a reflection on the approach to life as a regulatory activity and self-realization. For this, it will be necessary to redefine the concepts of health and disease, and make a crossover between the two. At the end of this trajectory, it will be found that these concepts can explain the identity between the concept and life, which leads to the unexpected conclusion that the cure is ultimately self-healing.
Ludus Vitalis, Jul 2013
El organismo contra el ambiente. El organismo contra otros organismos, en competencia por la supe... more El organismo contra el ambiente. El organismo contra otros organismos, en competencia por la supervivencia. El antagonismo y el enfrentamiento como única relación posible en la naturaleza. La tendencia a antropomorfizar la naturaleza y explicarla mediante conceptos y sucesos pertenecientes a la esfera humana. Un viaje a través de los mundos de Uexküll y Merleau-Ponty en búsqueda de saberes alternativos que nos permitan entender la relación desde otro punto de vista. El contrapunto e identificación de tonalidades coincidentes entre los programas de investigación de ambos pensadores como forma de demostrar las posibilidades de un abordaje más fructífero. El Umwelt como sistema generador de relaciones con sentido en el que sus participantes no son mutuamente excluyentes, sino que expresan una melodía que los incluye a todos.
Palabras clave: Umwelt, cuerpo, comportamiento, forma, estructura, intencionalidad, teleología, circularidad, relación de sentido, melodía.
The organism against its environment. The organism against other organisms, competing and struggling for life. Antagonism and confrontment as the only possible relation in nature. The tendency to anthropomorphize nature and explain it using concepts and facts from the human sphere. A stroll through the worlds of Uexküll and Merleau-Ponty in the search of alternative knowledge that allow us to understand relation from another point of view. A counterpoint and identification of common tonalities between the research programs from both thinkers as a way to demonstrate the possibilities of a more fruitful approach. Umwelt as a generative system of meaningful relations in which its participants are not mutually exclusive, but express a melody that include them all.
Keywords: Umwelt, body, behaviour, form, structure, intentionality, teleology, circularity, meaningful relation, melody.
Revista Iberoamericana de Ciencia, Tecnología y Sociedad (CTS), 2012
¿Cuál es la relación entre ciencia e ideología?. ¿Son dos cosas incompatibles, complementarias o ... more ¿Cuál es la relación entre ciencia e ideología?. ¿Son dos cosas incompatibles, complementarias o son la misma cosa?. ¿Debe evitar la ciencia dejarse “contaminar” por la ideología?. ¿Hay una única manera de hacer ciencia?. ¿Todas conducen a los mismos resultados y nos dan la misma visión del mundo?. Nos centraremos en la figura de Alexander Bogdanov, médico y filósofo ruso, para debatir sobre estos y otros temas de relevancia actual. Sus teorías dieron origen a lo que después se denominó la “teoría de las dos ciencias”, que da título a este trabajo.
Veterinary Immunology and Immunopathology, Jan 2013
Bovine viral diarrhea virus (BVDV) is considered an important cause of economic loss within bovin... more Bovine viral diarrhea virus (BVDV) is considered an important cause of economic loss within bovine herds worldwide. In Argentina, only the use of inactivated vaccines is allowed, however, the efficacy of inactivated BVDV vaccines is variable due to its low immunogenicity. The use of recombinant subunit vaccines has been proposed as an alternative to overcome this difficulty. Different studies on protection against BVDV infection have focused the E2 protein, supporting its putative use in subunit vaccines. Utilization of transgenic plants expressing recombinant antigens for the formulation of experimental vaccines represents an innovative and cost effective alternative to the classical fermentation systems. The aim of this work was to develop transgenic alfalfa plants (Medicago sativa, L.) expressing a truncated version of the structural protein E2 from BVDV fused to a molecule named APCH, that target to antigen presenting cells (APCH-tE2). The concentration of recombinant APCH-tE2 in alfalfa leaves was 1ug/gr at fresh weight and its expression remained stable after vegetative propagation. A methodology based an aqueous two phases system was standardized for concentration and partial purification of APCH-tE2 from alfalfa. Guinea pigs parentally immunized with leaf extracts developed high titers of neutralizing antibodies. In bovine, the APCH-tE2 subunit vaccine was able to induce BVDV-specific neutralizing antibodies. After challenge, bovines inoculated with 3 ug of APCH-tE2 produced in alfalfa transgenic plants showed complete virological protection.
Bovine viral diarrhea (BVD) infection caused by bovine viral diarrhea virus (BVDV), a Pestivirus ... more Bovine viral diarrhea (BVD) infection caused by bovine viral diarrhea virus (BVDV), a Pestivirus of the Flaviviridae family, is an important cause of morbidity, mortality and economical losses in cattle worldwide. E2 protein is the major glycoprotein of BVDV envelope and the main target for neutralising antibodies (NAbs). Different studies on protection against BVDV infection have focused on E2, supporting its putative use in subunit vaccines. A truncated version of type 1a BVDV E2 (tE2) expressed in mammalian cells was used to formulate an experimental oleous monovalent vaccine. Immunogenicity was studied through immunisation of guinea pigs and followed by trials in cattle. Calves of 8–12 months were vaccinated, twice with a 4 week interval, with either a tE2 subunit vaccine (n08), a whole virus inactivated vaccine (n08) or left untreated as negative control group (n08). Four weeks after the last immu-nisation the animals were experimentally challenged intrana-sally with a non-cythopathic BVDV strain. Following challenge, BVDV was isolated from all unvaccinated animals, while 6 out of 8 animals vaccinated with tE2 showed complete virological protection indicating that the tE2 vaccine presented a similar performance to a satisfactory whole virus inactivated vaccine.
Instituto Nacional de la Propiedad Industrial (INPI) - Boletín N° 537, 2009
Proteína de fusión con direccionamiento de antígenos vacunales a células presentadoras de antígen... more Proteína de fusión con direccionamiento de antígenos vacunales a células presentadoras de antígeno y sus aplicaciones. Se presenta una construcción génica que comprende operativamente unidas al menos una secuencia nucleotídica (A) que codifica para un polipéptido de SEQ ID Nº 1 que presenta una región que reconoce a la cadena b del antígeno DR de la Clase II presente en la superficie de las células presentadoras del antígeno, y una secuencia nucleotídica (B) que codifica para un antígeno vacunal de interés. Además se refiere a vectores recombinantes útiles para la expresión de la construcción génica de la presente, células y plantas transgénicas transformadas o transfectadas con dichos vectores, proteínas de fusión codificadas por la construcción génica presentada y vacunas que comprendan dichas proteínas de fusión.
[Patente P080101073]
World Intellectual Property Organization (WIPO), 2009
Fusion protein that directs vaccine antigens to antigen-presenting cells, and applications thereo... more Fusion protein that directs vaccine antigens to antigen-presenting cells, and applications thereof. The present invention relates to a gene construct that comprises, functionally linked, at least one nucleotide sequence (A) that encodes a polypeptide of SEQ ID No 1 that has a region that recognizes the β chain of the class II DR antigen present on the antigen-presenting cell surface; and a nucleotide sequence (B) that encodes a vaccine antigen of interest. Furthermore, the present invention relates to recombinant vectors that are useful in the expression of the gene construct of the invention, transgenic cells and plants transformed or transfected with said vectors, fusion proteins encoded by the gene construct of the invention and vaccines that comprise said fusion proteins.
[Patent WO/2009/112603]
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Papers by Agustin Ostachuk
The influence of Kurt Goldstein on the thinking of Georges Canguilhem extended throughout his entire work. This paper seeks to examine this relationship in order to conduct a study of the norm as a nexus or connection between the concept and life. Consequently, this work will be a reflection on the approach to life as a regulatory activity and self-realization. For this, it will be necessary to redefine the concepts of health and disease, and make a crossover between the two. At the end of this trajectory, it will be found that these concepts can explain the identity between the concept and life, which leads to the unexpected conclusion that the cure is ultimately self-healing.
Palabras clave: Umwelt, cuerpo, comportamiento, forma, estructura, intencionalidad, teleología, circularidad, relación de sentido, melodía.
The organism against its environment. The organism against other organisms, competing and struggling for life. Antagonism and confrontment as the only possible relation in nature. The tendency to anthropomorphize nature and explain it using concepts and facts from the human sphere. A stroll through the worlds of Uexküll and Merleau-Ponty in the search of alternative knowledge that allow us to understand relation from another point of view. A counterpoint and identification of common tonalities between the research programs from both thinkers as a way to demonstrate the possibilities of a more fruitful approach. Umwelt as a generative system of meaningful relations in which its participants are not mutually exclusive, but express a melody that include them all.
Keywords: Umwelt, body, behaviour, form, structure, intentionality, teleology, circularity, meaningful relation, melody.
[Patente P080101073]
[Patent WO/2009/112603]
The influence of Kurt Goldstein on the thinking of Georges Canguilhem extended throughout his entire work. This paper seeks to examine this relationship in order to conduct a study of the norm as a nexus or connection between the concept and life. Consequently, this work will be a reflection on the approach to life as a regulatory activity and self-realization. For this, it will be necessary to redefine the concepts of health and disease, and make a crossover between the two. At the end of this trajectory, it will be found that these concepts can explain the identity between the concept and life, which leads to the unexpected conclusion that the cure is ultimately self-healing.
Palabras clave: Umwelt, cuerpo, comportamiento, forma, estructura, intencionalidad, teleología, circularidad, relación de sentido, melodía.
The organism against its environment. The organism against other organisms, competing and struggling for life. Antagonism and confrontment as the only possible relation in nature. The tendency to anthropomorphize nature and explain it using concepts and facts from the human sphere. A stroll through the worlds of Uexküll and Merleau-Ponty in the search of alternative knowledge that allow us to understand relation from another point of view. A counterpoint and identification of common tonalities between the research programs from both thinkers as a way to demonstrate the possibilities of a more fruitful approach. Umwelt as a generative system of meaningful relations in which its participants are not mutually exclusive, but express a melody that include them all.
Keywords: Umwelt, body, behaviour, form, structure, intentionality, teleology, circularity, meaningful relation, melody.
[Patente P080101073]
[Patent WO/2009/112603]
Como parte de la primera estrategia, una versión truncada de la glicoproteína E2 (E2T) de BVDV, sin su dominio transmembrana, fue fusionada (o no) a un fragmento variable de simple cadena (ScFv), que reconoce una región conservada de las moléculas MHC clase II, y expresada establemente en células de mamífero (CHO-K1). Las proteínas fueron purificadas por cromatografía de afinidad (IMAC) a partir de los sobrenadantes de cultivo celular, y cuantificadas por SDS-PAGE y tinción con Coomasie blue. La productividad de las líneas celulares estables y la pureza proteica fueron del orden de 0,5 mg/L y 85 %, respectivamente. El direccionamiento resultó en un incremento de la unión superficial de antígeno e internalización por APCs, evidenciado por análisis de citometría de flujo. Provocó también un aumento concomitante de la estimulación y proliferación de células T in vitro. Además, el direccionamiento antigénico resultó en un cambio de polarización de la respuesta inmune desde un tipo Th1 a un tipo Th2. La vacuna no dirigida indujo la expresión de IFN-γ, mientras que la vacuna dirigida indujo predominantemente IL-4, lo cual fue revelado por qPCR. Animales bovinos inmunizados con la vacuna dirigida indujeron una respuesta inmune adaptativa y la producción de anticuerpos neutralizantes, a dosis más bajas que la vacuna no dirigida (2 inmunizaciones con una dosis de 0,2 ug). Como parte de la segunda estrategia, plantas transgénicas de alfalfa fueron generadas por infección de pecíolos con Agrobacterium tumefaciens recombinantes, que contenían los genes apropiados clonados en un vector pCAR río abajo del promotor CsVMV (Cassava vein mosaic virus). Las plantas transgénicas expresaron las proteínas recombinantes a niveles del orden de 1 ug/g de hoja fresca. Vacunas formuladas a partir de extractos vegetales fueron capaces de inducir una respuesta inmune y la producción de anticuerpos neutralizantes en bovinos, usando un esquema de 3 inmunizaciones con una dosis de 1 ug. En consecuencia, ambas estrategias fueron exitosas para el desarrollo de vacunas más eficientes contra BVDV, y demuestran los beneficios y potencial de un diseño racional de las vacunas.