Evaluación del efecto protector de Pichia pastoris expresando proteína quimérica IPath y catepsina como prototipo de vacuna oral en salmón del Atlántico (salmo salar) para el control de la caligidosis.
Loading...
Date
2025
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Universidad de Concepción
Abstract
Chile es el segundo mayor productor mundial de salmón del Atlántico (Salmo salar), contribuyendo al crecimiento económico del sur del país. No obstante, la salmonicultura enfrenta múltiples desafíos que afectan la salud y productividad de los peces, entre ellos la Caligidosis, una enfermedad causada por Caligus rogercresseyi, comúnmente llamado “piojo de mar”. Esta infestación deteriora la salud del pez, causando lesiones en la piel, alteraciones enzimáticas y debilitamiento del sistema inmunológico, lo que favorece la entrada de otros patógenos y genera considerables pérdidas económicas. Actualmente, el control del parásito se basa principalmente en tratamientos farmacológicos cuyo uso excesivo ha generado resistencia, lo que resalta la necesidad de desarrollar nuevas alternativas no farmacológicas. En este contexto, nuestro equipo de investigación del LBGA-INCAR ha evaluado antígenos como catepsina e IPath, en vacunas inyectables experimentales, logrando reducir entre un 57% y un 97% la carga parasitaria en estadios adultos, respectivamente. Si bien han demostrado eficacia, su aplicación en acuicultura enfrenta limitaciones asociadas al estrés por manipulación individual, dificultad de vacunar peces de gran tamaño y problemas de escalabilidad de proteínas recombinantes. Es por esto, que el objetivo de este estudio fue evaluar el uso de una formulación oral de los antígenos (IPath y catepsina) expresados en la levadura P. pastoris (Pp) en salmón del Atlántico frente a una infestación con piojos de mar. Se establecieron tres grupos experimentales con los antígenos IPath (Pp_IPath), catepsina (Pp_Cath) y una combinación (Pp_IP+Cath), junto a dos controles, alimento normal (Ctrl) y levadura no recombinante (Pp_Ctrl). Los peces fueron desafiados con 35 copépodos por individuo, iniciando el tratamiento al día siguiente. Los resultados mostraron una menor proporción de machos en los peces vacunados. El grupo Pp_Ctrl evidenció una reducción de Caligus significativa de adultos totales y hembras en comparación con el grupo control (Ctrl), mientras que en los demás tratamientos no se observaron diferencias significativas. Los peces vacunados con IPath indujeron una modulación de genes asociados al transporte de hierro y a la respuesta inmune adaptativa, mientras que en piojos recuperados se evidenciaron alteraciones en genes vinculados al estrés oxidativo. Estos hallazgos sugieren que la inmunización oral con levaduras recombinantes estimula la respuesta inmune del hospedador e impacta indirectamente en el metabolismo del ectoparásito, respaldando el potencial de IPath y P. pastoris como candidatos para vacunas orales en salmonicultura.
Chile ranks as the second-largest global producer of Atlantic salmon (Salmo salar), contributing to the economic growth of the southern part of the country. However, salmon farming faces numerous challenges that impact the health and productivity of the fish, including caligidosis, a disease caused by Caligus rogercresseyi, commonly known as 'sea lice.' This infestation damages the fish's health, leading to skin lesions, enzymatic changes, and a weakened immune system, which allows other pathogens to enter and causes significant economic losses. Currently, parasite control mainly depends on pharmacological treatments, but overuse has led to resistance, emphasizing the need for new non pharmacological solutions. In this context, our research team at LBGA-INCAR has tested antigens such as cathepsin and IPath in experimental injectable vaccines, achieving a reduction of between 57% and 97% in parasite load during the adult stages. Although effective, their use in aquaculture is limited by stress from individual handling, the impracticality for smaller fish, and the challenges of large-scale recombinant protein production. Therefore, this study aim to evaluate the use of oral formulation with the antigens (IPath and cathepsin) expressed in the yeast P. pastoris (Pp) for Atlantic salmon against sea lice infestation. Three experimental groups were created with the antigens Pp_IPath, Pp_Cath, and a combination (Pp_IP+Cath), along with two controls: normal feed (Ctrl) and non-recombinant yeast (Pp_Ctrl). The fish were challenged with 35 copepods per individual, starting the treatment the next day. Results showed a lower parasite load in males. The Pp_Ctrl group exhibited a significant decrease in total counts and female counts compared to the control group (Ctrl), while no significant differences appeared in the other treatments. Fish vaccinated with IPath showed modulation of genes related to iron transport and adaptive immune response, whereas in recovered lice, changes were observed in genes associated with oxidative stress. These findings suggest that oral immunization with recombinant yeasts stimulates the host's immune response and indirectly affects the parasite's metabolism, supporting the potential of IPath and P. pastoris as candidates for oral vaccines in salmon farming.
Chile ranks as the second-largest global producer of Atlantic salmon (Salmo salar), contributing to the economic growth of the southern part of the country. However, salmon farming faces numerous challenges that impact the health and productivity of the fish, including caligidosis, a disease caused by Caligus rogercresseyi, commonly known as 'sea lice.' This infestation damages the fish's health, leading to skin lesions, enzymatic changes, and a weakened immune system, which allows other pathogens to enter and causes significant economic losses. Currently, parasite control mainly depends on pharmacological treatments, but overuse has led to resistance, emphasizing the need for new non pharmacological solutions. In this context, our research team at LBGA-INCAR has tested antigens such as cathepsin and IPath in experimental injectable vaccines, achieving a reduction of between 57% and 97% in parasite load during the adult stages. Although effective, their use in aquaculture is limited by stress from individual handling, the impracticality for smaller fish, and the challenges of large-scale recombinant protein production. Therefore, this study aim to evaluate the use of oral formulation with the antigens (IPath and cathepsin) expressed in the yeast P. pastoris (Pp) for Atlantic salmon against sea lice infestation. Three experimental groups were created with the antigens Pp_IPath, Pp_Cath, and a combination (Pp_IP+Cath), along with two controls: normal feed (Ctrl) and non-recombinant yeast (Pp_Ctrl). The fish were challenged with 35 copepods per individual, starting the treatment the next day. Results showed a lower parasite load in males. The Pp_Ctrl group exhibited a significant decrease in total counts and female counts compared to the control group (Ctrl), while no significant differences appeared in the other treatments. Fish vaccinated with IPath showed modulation of genes related to iron transport and adaptive immune response, whereas in recovered lice, changes were observed in genes associated with oxidative stress. These findings suggest that oral immunization with recombinant yeasts stimulates the host's immune response and indirectly affects the parasite's metabolism, supporting the potential of IPath and P. pastoris as candidates for oral vaccines in salmon farming.
Description
Tesis presentada para optar al título de Ingeniero/a en Biotecnología Marina y Acuicultura.
Keywords
Salmón del atlántico, Salmonicultura, Pichia pastoris, Peces Parásitos