Interstrain conservation of babesial RAP-1 surface-exposed B-cell epitopes despite rap-1 genomic polymorphism

Members of the babesial rhoptry-associated protein 1 (RAP-1) family express surface-exposed B-cell epitopes and are candidate antigens for vaccine development. The relationship between rap-1 genomic polymorphism and surface-exposed B-cell epitope expression was analyzed by comparison of biological clones of Mexico strain Babesia bigemina and Babesia bovis with strains isolated in Argentina. Despite genomic polymorphism between strains, including sequences located within the open reading frame, defined RAP-1 B-cell surface epitopes and RAP-1 molecular size were conserved in both B. bovis and B. bigemina

Seroprevalencia de paratuberculosis bovina en rodeos de cría y de leche de dos departamentos de la provincia de Santa Fe (Argentina)

Paratuberculosis (PTB) is a granulomatous chronic disease of the gastrointestinal tract of domestic and wild ruminants, caused by Mycobacterium avium subsp. paratuberculosis (MAP). The disease has been identified previously in dairy and beef cattle herds of Argentina, however the prevalence estimates are scarce. To characterize the PTB situation in both cattle production system of Santa Fe province, the serological prevalence in dairy and beef cattle herds was determined through a commercial ELISA. The study was carried on Castellanos and San Cristobal departments that include a significant proportion of the provincial cattle that produce milk and meat, respectively. Seventy herds were studied for each productive system, with a minimum of 20 cows sampled per herd. PTB prevalence at the herd and bovines level was 35.6% and 2.1% for dairy cattle and 66% and 9% for beef cattle respectively. Unexpectedly, the meat production systems showed higher prevalence than dairy systems. These results strongly suggest that Argentina should implement an official PTB control program that include particularly breeder cabins, to preclude its spread with livestock movement.Fil: Abdala, A. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimetal Agropecuaria Rafaela (EEA). Santa Fe, ArgentinaFil: Aguirre N. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimetal Agropecuaria Rafaela (EEA). Santa Fe, ArgentinaFil: Luca, E. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Santa Fe, ArgentinaFil: Torioni de Echaide, S. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimetal Agropecuaria Rafaela (EEA). Santa Fe, ArgentinaLa paratuberculosis (PTB) es una enfermedad crónica granulomatosa del tracto gastrointestinal causada por Mycobacterium avium subsp. paratuberculosis (MAP), que afecta a rumiantes domésticos y silvestres. La enfermedad ha sido identificada en rodeos bovinos productores de leche y carne de Argentina, pero con escasas estimaciones de prevalencia. Para caracterizar la situación de la PTB en rodeos bovinos de la provincia de Santa Fe, se determinó la prevalencia serológica en bovinos productores de leche y carne mediante un ELISA comercial. El estudio se llevó a cabo en los departamentos Castellanos y San Cristóbal que incluyen una proporción significativa del ganado provincial que produce leche y carne, respectivamente. Se estudiaron 70 establecimientos por sistema productivo, con un mínimo de 20 vacas por rodeo. La prevalencia de PTB en rodeos y bovinos fue de 35,6% y del 2,1% para ganado lechero y del 66% y 9% para ganado de carne, respectivamente. Contrariamente a lo esperado, los sistemas extensivos para la producción de carne tuvieron prevalencias más elevadas que los sistemas lecheros. Estos resultados sugieren la necesidad de implementar un programa oficial para el control de PTB que incluya inicialmente cabañas de reproductores para evitar su propagación con los movimientos de ganado

Antibody against an Anaplasma marginale MSP5 epitope common to tick and erythrocyte stages identifies persistently infected cattle

A protein epitope of major surface protein 5 (MSP5), defined by monoclonal antibody (MAb) ANAF16C1, is conserved among Anaplasma species (E. S. Visser, T. C. McGuire, G. H. Palmer, W. C. Davis, V. Shkap, E. Pipano, and D. P. Knowles, Jr., Infect. Immun. 60:5139-5144, 1992) and is expressed in the salivary glands of infected ticks. A competitive inhibition ELISA (cELISA) for the detection of bovine anti-MSP5 antibodies was developed by using purified recombinant MSP5 fusion protein and MAb ANAF16C1. The specificity of the recombinant-MSP5 cELISA within North America was established by using 261 serum samples from cattle in the regions of Hawaii and Northern Ontario where anaplasmosis is not endemic and from cattle proven by splenectomy or subinoculation of whole blood into susceptible splenectomized recipients to be uninfected. The maximum percent inhibition by these sera was 18%. Sera known to be positive were obtained from 35 cattle either experimentally inoculated with infected erythrocytes or exposed to infected Dermacentor andersoni ticks. Thirty-four of the 35 serum samples inhibited MAb ANAF16C1 binding by > or = 25%. During acute infection, the MSP5 cELISA detected antibodies prior to or concomitantly with the appearance of rickettsiae in erythrocytes. Antibodies were detectable in sera from persistently infected cattle inoculated as long as 6 years previously

Situación de la Babesiosis y Anaplasmosis de los Bovinos en el Sudoeste de la Provincia del Chaco (Argentina)

Mediante pruebas de ELISA indirecto y de competición se estimaron las seroprevalencias paraBabesia bovis, Babesia bigemina y Anaplasma marginale en establecimientos ganaderos del sudoeste de la provincia del Chaco. El área se encuentra en la zona infestada con Rhipicephalus (Boophilus) microplus. Se analizaron 776 muestras de suero de terneras de 4 a 8 meses pertenecientes a 33 establecimientos (aprox. 25 por establecimiento) y se calculó la tasa de inoculación (h; probabilidad diaria de infección) para cada rodeo. El 91% (30) de los establecimientos se encontraron en una situación de inestabilidad enzoótica para todos o para alguno de los tres microorganismos, con el consiguiente riesgo de brotes de importancia económica. Los resultados muestran que es un error considerar que un rodeo presenta inmunidad contra estos microorganismos sólo por provenir de un área infestada con garrapatas.Fil: Mastropaolo, Mariano. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Santa Fe. Estacion Experimental Agropecuaria Rafaela. Agencia de Extension Rural Rafaela.; ArgentinaFil: Torioni de Echaide, Susana Marta. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Santa Fe. Estacion Experimental Agropecuaria Rafaela. Agencia de Extension Rural Rafaela.; ArgentinaFil: Cuatrin, Alejandra Lorena. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Santa Fe. Estacion Experimental Agropecuaria Rafaela. Agencia de Extension Rural Rafaela.; ArgentinaFil: Arece, Hugo. Sin filiación; ArgentinaFil: Lobato, Sergio. Sin filiación; ArgentinaFil: Mangold, Atilio Jose. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Santa Fe. Estacion Experimental Agropecuaria Rafaela. Agencia de Extension Rural Rafaela.; Argentin

The novel protein BboRhop68 is expressed by intraerythrocytic stages of Babesia bovis

The apical complex of intracellular hemoparasites contains organelles like micronemes and rhoptries, specialized structures required for adherence and invasion of host cells. Several molecules discharged from rhoptries have been identified from Plasmodium spp., but only a single rhoptry associated protein-1 (RAP-1) has been characterized from Babesia bovis. In silico search of the B. bovis genome allowed to identifying a sequence homologous to the gene that encodes a P. falciparum rhoptry protein PfRhop148. The intron-less 1830. bp novel gene, predicted a 68. kDa protein, and it was highly conserved among different B. bovis strains and isolates. The deducted protein from the B. bovis T2Bo strain, named BboRhop68, showed two putative transmembrane domains, at least seven B-cell epitopes, and a well conserved DUF501 super family domain. The bborhop68 gene was amplified, analyzed and compared among different B. bovis strains and isolates showing overall high sequence conservation. A fragment of bborhop68 was expressed as a recombinant fusion protein (rBboRhop68). The mice anti-rBboRhop68 serum identified the novel protein in intraerythrocytic trophozoites and merozoites by WB and ELISA, but not in free merozoites. Sera from naturally and experimentally infected bovines also recognized BboRhop68, suggesting that it is expressed and immunogenic during B. bovis infection. Fluorescence microscopy analysis using anti-rBboRhop68 antibodies showed a rod structure associated to trophozoites and merozoites infected erythrocytes, but this pattern of reactivity was not observed in free merozoites. The BboRhop68 was also not detected in ELISA based on solubilized merozoites. Thus, at least three independent lines of evidence support differential expression of BboRhop68 in intraerythrocytic stages of B. bovis and its possible functional role immediately after B. bovis erythrocyte invasion. The results of this work suggest that BboRhop68 could be considered as a novel additional target for developing improved methods to control bovine babesiosis.Fil: Baravalle, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Thompson, Carolina Soledad. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Torioni de Echaide, S.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Palacios, Carlos Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología ; ArgentinaFil: Valentini, B.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Suárez, C. E.. United States Department of Agriculture. Agricultural Research Service; ArgentinaFil: Christensen, M. Florín. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Echaide, Ignacio Eduardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentin