RESUMEN
Cysteine proteinases released by Fasciola hepatica play a key role in parasite feeding, migration through host tissues and in immune evasion. Hence, a recombinant cysteine proteinase (CPFhW) expressed as inclusion bodies in Escherichia coli was used for enteral vaccination of rats against fasciolosis. We managed to activate this proteinase and found it to have cathepsin L1-like substrate preference. Enteral vaccination of rats induced a 78-80% protection against challenge with fluke metacercariae (mc). The immunised rats showed clear immunological response. The challenge with mc caused a remarkable infiltration of eosinophils into the peritoneal cavity of both the vaccinated rats and challenge control rats. However, CD8+ and CD4+ lymphocytes appeared in significantly higher numbers in the peritoneal fluid of vaccinated rats than in controls.
Asunto(s)
Catepsinas/inmunología , Escherichia coli/genética , Fasciola hepatica/inmunología , Fascioliasis/prevención & control , Vacunas Sintéticas/administración & dosificación , Administración Oral , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Catepsinas/genética , Fasciola hepatica/enzimología , Fasciola hepatica/genética , Fascioliasis/inmunología , Femenino , Cuerpos de Inclusión , Masculino , Cavidad Peritoneal , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/metabolismo , Vacunación/métodos , Vacunas Sintéticas/inmunologíaRESUMEN
A fragment of non-glycosylated E2 antigen of classical swine fever virus (CSFV), lacking the trans-membrane anchor (TM-) of the native glycoprotein, was produced in recombinant Escherichia coli strain BL21(DE3) in the form of inclusion bodies. These inclusion bodies isolated from the bacteria cells were administrated orally to mice twice at either 10 or 50 microg per dose. Each mouse fed with inclusion bodies carrying the E2 antigen responded with plasma antibodies and/or fecal IgA at least once during the entire investigation. Our study showed the capacity of inclusion bodies to induce both systemic and mucosal responses as well as to evoke relatively-long mucosal memory when fed to mice at low-number vaccination schedule and without any adjuvant. We propose the use of inclusion bodies for oral vaccination as an alternative to artificial systems for delivery of recombinant antigens by the oral route. Very few steps are needed to obtain an antigen ready for use as a vaccine. The procedure is easy and inexpensive and can be used for development of vaccine against classical swine fever.