RESUMEN
Microlipid vesicles (MLV) have a broad spectrum of applications for the delivery of molecules, ranging from chemical compounds to proteins, in both in vitro and in vivo conditions. In the present study, we developed a new set of nanosize multilayer lipid vesicles (NMVs) containing a unique combination of lipids. The NMVs enable the adsorption of histidine-tagged proteins at the vesicle surface and were demonstrated to be suitable for the in vivo delivery of antigens. The NMVs contained a combination of neutral (DOPC) and anionic (DPPG) lipids in the inner membrane and an external layer composed of DOPC, cholesterol, and a nickel-containing lipid (DGS-NTA [Ni]). NMVs combined with a recombinant form of the B subunit of the Shiga toxin (rStx2B) produced by certain enterohemorragic Escherichia coli (EHEC) strains enhanced the immunogenicity of the antigen after parenteral administration to mice. Mice immunized with rStx2B-loaded NMVs elicited serum antibodies capable of neutralizing the toxic activities of the native toxin; this result was demonstrated both in vitro and in vivo. Taken together, these results demonstrated that the proposed NMVs represent an alternative for the delivery of antigens, including recombinant proteins, generated in different expression systems.
Asunto(s)
Anticuerpos Antibacterianos/inmunología , Sistemas de Liberación de Medicamentos/métodos , Escherichia coli Enterohemorrágica/inmunología , Infecciones por Escherichia coli/inmunología , Lípidos/química , Toxina Shiga/inmunología , Animales , Formación de Anticuerpos , Antígenos Bacterianos/administración & dosificación , Antígenos Bacterianos/química , Antígenos Bacterianos/inmunología , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/instrumentación , Escherichia coli Enterohemorrágica/genética , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/prevención & control , Femenino , Humanos , Inmunización , Ratones , Ratones Endogámicos BALB C , Nanopartículas/administración & dosificación , Nanopartículas/química , Toxina Shiga/administración & dosificación , Toxina Shiga/químicaAsunto(s)
Anticuerpos Monoclonales/inmunología , Toxina Shiga/antagonistas & inhibidores , Toxina Shiga/toxicidad , Escherichia coli Shiga-Toxigénica/patogenicidad , Línea Celular , Síndrome Hemolítico-Urémico/prevención & control , Humanos , Inmunoglobulina A/inmunología , Inmunoglobulina G/inmunología , Toxina Shiga/inmunologíaRESUMEN
The central role of the immune system is the preservation of the health against several pathogenic microbes and injury agents. However, on special conditions defensive mechanisms triggered towards the foreign agent can damage the host. Clinical and experimental evidence indicate that inflammatory reaction triggered by the main components of Shiga toxin (Stx)-producing Escherichia coil (STEC), participate in the evolution to the complete form of HUS. When children are diagnosed of HUS, they present evidence that have suffered a very strong and early inflammatory response. These features include: the presence of a marked neutrophilia, the polymorfonuclear leucocytes (PMN) are "deactivated or exhausted" and the monocytes are differentiated towards an inflammatory phenotype (CD14-reduced and CD16-enhanced membrane expression). In addition, HUS-patients show a marked reduction in the absolute and relative number of leucocytes carrying the receptor (CX3CR1) for the chemokine "Fractalkine" (FKN, CX3CL1), which are the classic monocytes and Natural Killer cells (NK). All these cells express a high cytotoxic potencial. The chemokine FKN is expressed in endothelial and epithelial renal cells, and is involved in the pathogenic mechanism of different nephropathies. Noteworthy, we found a significant correlation between the severity of the renal damage (as days of anuria) and the alterations described above. Finally, the protective role of specific immune response, mainly through the antibody production with Stx-neutralizing capacity, is discussed.
Asunto(s)
Síndrome Hemolítico-Urémico/inmunología , Inmunidad Innata/inmunología , Activación Neutrófila/inmunología , Toxina Shiga/toxicidad , Animales , Antígenos CD/inmunología , Quimiocina CX3CL1/inmunología , Citocinas/inmunología , Modelos Animales de Enfermedad , Escherichia coli/inmunología , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/inmunología , Factores de Crecimiento de Fibroblastos/inmunología , Síndrome Hemolítico-Urémico/terapia , Humanos , Células Asesinas Naturales/inmunología , Murinae , Neutrófilos/inmunología , Ratas , Diálisis Renal , Toxina Shiga/antagonistas & inhibidores , Toxina Shiga/inmunologíaRESUMEN
Cattle are recognized as the major reservoir of STEC and the source of infection for human beings. Until recently, intervention strategies to decrease the contamination of meat products have been focused on the slaughter plant with the application of practices to reduce the contamination and proliferation of STEC. This has now changed following the development of intervention strategies in the farm. This could be one of the most important points of intervention to lower the incidence of human infection. Vaccines, probiotics, bacteriophages, and changes in production practices may be useful as strategies to control EHEC in the cattle. The application of such intervention measures could be difficult due to the fact that this zoonotic agent rarely causes disease in bovines. The HUS is endemic in Argentina, and the factors leading to this epidemiological situation remain unknown. However, intervention strategies undoubtedly will contribute to reduce the incidence of this zoonosis.
Asunto(s)
Reservorios de Enfermedades/microbiología , Infecciones por Escherichia coli/prevención & control , Escherichia coli O157/patogenicidad , Animales , Proteínas Bacterianas/metabolismo , Bacteriófagos/inmunología , Bovinos , Infecciones por Escherichia coli/inmunología , Escherichia coli O157/virología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/uso terapéutico , Vacunas contra Escherichia coli/uso terapéutico , Síndrome Hemolítico-Urémico/inmunología , Síndrome Hemolítico-Urémico/prevención & control , Humanos , Lactobacillus acidophilus , Fosfoproteínas/genética , Fosfoproteínas/uso terapéutico , Probióticos/uso terapéutico , Toxina Shiga/biosíntesis , Toxina Shiga/inmunología , VirulenciaRESUMEN
The central role of the immune system is the preservation of the health against several pathogenic microbes and injury agents. However, on special conditions defensive mechanisms triggered towards the foreign agent can damage the host. Clinical and experimental evidence indicate that inflammatory reaction triggered by the main components of Shiga toxin (Stx)-producing Escherichia coil (STEC), participate in the evolution to the complete form of HUS. When children are diagnosed of HUS, they present evidence that have suffered a very strong and early inflammatory response. These features include: the presence of a marked neutrophilia, the polymorfonuclear leucocytes (PMN) are "deactivated or exhausted" and the monocytes are differentiated towards an inflammatory phenotype (CD14-reduced and CD16-enhanced membrane expression). In addition, HUS-patients show a marked reduction in the absolute and relative number of leucocytes carrying the receptor (CX3CR1) for the chemokine "Fractalkine" (FKN, CX3CL1), which are the classic monocytes and Natural Killer cells (NK). All these cells express a high cytotoxic potencial. The chemokine FKN is expressed in endothelial and epithelial renal cells, and is involved in the pathogenic mechanism of different nephropathies. Noteworthy, we found a significant correlation between the severity of the renal damage (as days of anuria) and the alterations described above. Finally, the protective role of specific immune response, mainly through the antibody production with Stx-neutralizing capacity, is discussed.(AU)
Asunto(s)
Humanos , Animales , Ratas , Síndrome Hemolítico-Urémico/inmunología , Inmunidad Innata/inmunología , Toxina Shiga/toxicidad , Activación Neutrófila/inmunología , Antígenos CD/inmunología , Quimiocinas CX3C/inmunología , Escherichia coli/inmunología , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/inmunología , Factores de Crecimiento de Fibroblastos/inmunología , Síndrome Hemolítico-Urémico/terapia , Células Asesinas Naturales/inmunología , Murinae , Neutrófilos/inmunología , Diálisis Renal , Toxina Shiga/antagonistas & inhibidores , Toxina Shiga/inmunología , Citocinas/inmunología , Modelos Animales de EnfermedadRESUMEN
Cattle are recognized as the major reservoir of STEC and the source of infection for human beings. Until recently, intervention strategies to decrease the contamination of meat products have been focused on the slaughter plant with the application of practices to reduce the contamination and proliferation of STEC. This has now changed following the development of intervention strategies in the farm. This could be one of the most important points of intervention to lower the incidence of human infection. Vaccines, probiotics, bacteriophages, and changes in production practices may be useful as strategies to control EHEC in the cattle. The application of such intervention measures could be difficult due to the fact that this zoonotic agent rarely causes disease in bovines. The HUS is endemic in Argentina, and the factors leading to this epidemiological situation remain unknown. However, intervention strategies undoubtedly will contribute to reduce the incidence of this zoonosis.(AU)
Asunto(s)
Humanos , Animales , Bovinos , Reservorios de Enfermedades/microbiología , Infecciones por Escherichia coli/prevención & control , Escherichia coli O157/patogenicidad , Proteínas Bacterianas/metabolismo , Bacteriófagos/inmunología , Infecciones por Escherichia coli/inmunología , Escherichia coli O157/virología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/uso terapéutico , Vacunas contra Escherichia coli/uso terapéutico , Síndrome Hemolítico-Urémico/inmunología , Síndrome Hemolítico-Urémico/prevención & control , Lactobacillus acidophilus , Fosfoproteínas/genética , Fosfoproteínas/uso terapéutico , Probióticos/uso terapéutico , Toxina Shiga/biosíntesis , Toxina Shiga/inmunologíaRESUMEN
The central role of the immune system is the preservation of the health against several pathogenic microbes and injury agents. However, on special conditions defensive mechanisms triggered towards the foreign agent can damage the host. Clinical and experimental evidence indicate that inflammatory reaction triggered by the main components of Shiga toxin (Stx)-producing Escherichia coil (STEC), participate in the evolution to the complete form of HUS. When children are diagnosed of HUS, they present evidence that have suffered a very strong and early inflammatory response. These features include: the presence of a marked neutrophilia, the polymorfonuclear leucocytes (PMN) are "deactivated or exhausted" and the monocytes are differentiated towards an inflammatory phenotype (CD14-reduced and CD16-enhanced membrane expression). In addition, HUS-patients show a marked reduction in the absolute and relative number of leucocytes carrying the receptor (CX3CR1) for the chemokine "Fractalkine" (FKN, CX3CL1), which are the classic monocytes and Natural Killer cells (NK). All these cells express a high cytotoxic potencial. The chemokine FKN is expressed in endothelial and epithelial renal cells, and is involved in the pathogenic mechanism of different nephropathies. Noteworthy, we found a significant correlation between the severity of the renal damage (as days of anuria) and the alterations described above. Finally, the protective role of specific immune response, mainly through the antibody production with Stx-neutralizing capacity, is discussed.
Asunto(s)
Humanos , Animales , Ratas , Síndrome Hemolítico-Urémico/inmunología , Inmunidad Innata/inmunología , Activación Neutrófila/inmunología , Toxina Shiga/toxicidad , Antígenos CD/inmunología , /inmunología , Citocinas/inmunología , Modelos Animales de Enfermedad , Infecciones por Escherichia coli/inmunología , Escherichia coli/inmunología , Escherichia coli/patogenicidad , Factores de Crecimiento de Fibroblastos/inmunología , Síndrome Hemolítico-Urémico/terapia , Células Asesinas Naturales/inmunología , Murinae , Neutrófilos/inmunología , Diálisis Renal , Toxina Shiga/antagonistas & inhibidores , Toxina Shiga/inmunologíaRESUMEN
Cattle are recognized as the major reservoir of STEC and the source of infection for human beings. Until recently, intervention strategies to decrease the contamination of meat products have been focused on the slaughter plant with the application of practices to reduce the contamination and proliferation of STEC. This has now changed following the development of intervention strategies in the farm. This could be one of the most important points of intervention to lower the incidence of human infection. Vaccines, probiotics, bacteriophages, and changes in production practices may be useful as strategies to control EHEC in the cattle. The application of such intervention measures could be difficult due to the fact that this zoonotic agent rarely causes disease in bovines. The HUS is endemic in Argentina, and the factors leading to this epidemiological situation remain unknown. However, intervention strategies undoubtedly will contribute to reduce the incidence of this zoonosis.
Asunto(s)
Humanos , Animales , Bovinos , Reservorios de Enfermedades/microbiología , Infecciones por Escherichia coli/prevención & control , /patogenicidad , Proteínas Bacterianas , Bacteriófagos/inmunología , Infecciones por Escherichia coli/inmunología , /virología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/uso terapéutico , Vacunas contra Escherichia coli/uso terapéutico , Síndrome Hemolítico-Urémico/inmunología , Síndrome Hemolítico-Urémico/prevención & control , Lactobacillus acidophilus , Fosfoproteínas/genética , Fosfoproteínas/uso terapéutico , Probióticos/uso terapéutico , Toxina Shiga/biosíntesis , Toxina Shiga/inmunologíaRESUMEN
Secretory immunoglobulin A (sIgA) is a primary factor responsible for preventing attachment of enteropathogens to gut epithelium in breastfeeding infants. We compared the frequency of sIgA to major surface antigens of enterohemorrhagic Escherichia coli (EHEC) in milk of 123 women from the United States and Mexico to determine whether regional differences existed in the frequency of antibodies to these surface antigens. In both groups of women, milk commonly has sIgA against various EHEC lipopolysaccharides, EspA, EspB, intimin, and less frequently against Shiga toxin. The study suggests that persons living in the United States are exposed to attaching/effacing enteropathogens more frequently than is generally assumed. The low frequency of antibodies to Stx1 (in 12% of Mexican and in 22% of U.S. samples) suggests that the rare appearance of hemolytic uremic syndrome in adults is not due to neutralization of toxin at the gut level. Only anti-EspA is found in most milk samples from both populations of women. EspA may represent a useful target for an immunization strategy to prevent EHEC disease in humans.