Person:
Sánchez Sánchez, Roberto

First Name

Roberto

Last Name

Sánchez Sánchez

URI

https://hdl.handle.net/20.500.14352/81642

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Veterinaria

Department

Sanidad Animal

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Now showing 1 - 10 of 15

Toxoplasmosis y neosporosis en rumiantes domésticos: normalización de modelos animales y evaluación de nuevos fármacos
(2019) Sánchez Sánchez, Roberto; Ortega Mora, Luis Miguel; Ferre Pérez, Ignacio; Re, Michela
Toxoplasma gondii y Neospora caninum son parásitos apicomplejos muy relacionados filogenéticamente y considerados como unas de las principales causas de aborto infeccioso en pequeños rumiantes y ganado vacuno respectivamente en todo el mundo. Sin embargo, recientemente, la importancia de N. caninum como agente causante de abortos en ganado ovino se ha incrementado enormemente. T. gondii en pequeños rumiantes y N. caninum en ganado vacuno presentan una elevada prevalencia y producen importantes pérdidas económicas como consecuencia del fallo reproductivo. T. gondii en ganado ovino produce principalmente aborto tras una primoinfección con ooquistes durante la gestación mientras que N. caninum puede producir abortos tras una infección durante la gestación o tras la recrudescencia de una infección crónica. Para el control de la toxoplasmosis en ganado ovino existe una vacuna viva atenuada comercializada (ToxovaxTM), la cual reduce parcialmente los abortos asociados a T. gondii, mientras que la la única vacuna comercializada hasta el momento para la neosporosis en ganado vacuno (Neoguard), basada en taquizoitos muertos, se ha retirado del mercado debido a su baja eficacia. En relación al tratamiento, se han probado diferentes clases de fármacos tales como macrólidos, poliéteres ionóforos, inhibidores de la síntesis del folato, quinolonas y triazinas y han mostrado eficacia moderada. Por lo tanto, hasta el momento, no hay fármacos disponibles para el tratamiento de la toxoplasmosis y la neosporosis en rumiantes. Asi pues, el desarrollo de medidas de control es de gran importancia...
Project number: 290
Parasitología Interactiva
(2016) Gómez Bautista, Mercedes; Ortega Mora, Luis Miguel; Álvarez García, Gema; Ferré Pérez, Ignacio; Moreno Gonzalez, Javier; Gutierrez Expósito, Daniel; Arranz-Solís, David; Pastor Fernández, Iván; Rojo Montejo, Silvia; Sánchez Sánchez, Roberto; García Lunar, Paula; Jiménez Meléndez, Alejandro; Jimenez Pelayo, Laura; García Sánchez, Marta; Diezma Díaz, Carlos; Horcajo Iglesias, María Del Pilar; Regidor Cerrillo, Javier; Pérez Villalobos, Natividad; Collantes Fernández, Esther
Desarrollo de una guía interactiva donde se muestran los ciclos biológicos,imágenes y dibujos de los estadios evolutivos de los principales géneros y especies de parásitos protozoos relevantes en al ámbito veterinario.
A systematic review and meta-analysis of the validation of serological methods for detecting anti-Toxoplasma gondii antibodies in humans and animals
(Veterinary Parasitology, 2024) Huertas López, Ana; Cantos Barreda, Ana; Martínez-Carrasco, Carlos; Ibáñez López, Francisco Javier; Martínez Subiela, Silvia; Cerón, José Joaquín; Sánchez Sánchez, Roberto; Álvarez García, Gema
Toxoplasma gondii is a paradigmatic zoonotic parasite from the One Health perspective, since it is broadly distributed and virtually infects all warm-blooded species. A wide variety of serological techniques have been developed to detect T. gondii infection in humans and animals. Our aim was to describe and compare the main characteristics of these serological tests and validation processes and to critically analyze whether these tests meet the standards required to ensure an accurate serological diagnosis. The current systematic review and meta-analysis included 134 studies that were published from 2013 to 2023. QUADAS 2 tool was used to evaluate the quality of the included studies. A total of 52 variables related to the characteristics of the techniques and analytical and diagnostic validation parameters were studied. A wider panel of tests was developed for humans, including techniques exclusively developed for humans that involve costly equipment and the measurement of different Ig isotypes that are considered biomarkers of congenital toxoplasmosis. Studies conducted in humans frequently employed commercial techniques as reference tests, measured different immunoglobulin isotypes with a predominance for IgG (>50%) and discriminated between acute and chronic infections. In animals, the most commonly used reference techniques were in-house tests, which almost exclusively detected IgG. Common limitations identified in a large number of studies were some misunderstandings of the terms “gold standard” and “reference test” and the absence of information about the negative and positive control sera used or the exact cutoff employed, which were independent of the quality of the study. There is a lack of analytical validation, with few evaluations of cross-reactivity with other pathogens. Diagnostic odds ratio values showed that indirect ELISA based on native or chimeric antigens performed better than other tests. The reproducibility of serological test results in both humans and animals is not guaranteed due to a lack of relevant information and analytical validation. Thus, several key issues should be considered in the future, including interlaboratory ring trials.
Project number: 25
Parasit`Xpert, un blog de Parasitología Veterinaria
(2023) Ferré Pérez, Ignacio; Ortega Mora, Luis Miguel; Álvarez García, Gema; Collantes Fernández, Esther; Horcajo Iglesias, María Del Pilar; Calero Bernal, Rafael; Pastor Fernández, Iván; Arranz-Solís, David; Sánchez Sánchez, Roberto; Regidor Cerrillo, Javier; Hecker, Yanina Paola
Parasit’Xpert es un blog sobre enfermedades parasitarias de los rumiantes domésticos para el veterinario (https://parasitxpert.es/). Su objetivo es ser un punto de encuentro y referencia para los profesionales del sector y estudiantes de veterinaria que quieran conocer y profundizar en el campo de las enfermedades parasitarias. La plataforma se inició en enero de 2021 y se estructura en diversas secciones prácticas: parásito del mes, ¿sabías qué?, diagnóstico, control, zoonosis y avances. El grupo SALUVET y la empresa de transferencia del conocimiento universitario SALUVET-Innova han puesto en marcha la web Parasit’xpert junto a la empresa farmacéutica Boehringer Ingelheim Animal Health España. El objetivo general del presente proyecto de innovación docente fue desarrollar el blog Parasit’Xpert (https://parasitxpert.es/) ya en activo e implementar un plan de difusión promocional para incrementar el número de usuarios, especialmente en países hispanohablantes.
Project number: 262
Parasitología interactiva: Protozoos y afines
(2018) Collantes Fernández, Esther; Gómez Bautista, Mercedes; Ortega Mora, Luis Miguel; Álvarez García, Gema; Ferré Pérez, Ignacio; García Lunar, Paula; Sánchez Sánchez, Roberto; Jiménez Meléndez, Alejandro; García Sánchez, Marta; Jiménez Pelayo, Laura; Diezma Díaz, Carlos; Regidor Cerrillo, Javier; Moreno González, Javier; Horcajo Iglesias, María Del Pilar
Desarrollo de una guía interactiva donde se muestran los ciclos biológicos, imágenes y dibujos de los estadios evolutivos de los principales géneros y especies de parásitos protozoos relevantes en al ámbito veterinario.
A comparative study of serological tests used in the diagnosis of Toxoplasma gondii infection in small ruminants evidenced the importance of cross-reactions for harmonizing diagnostic performance
(Research in Veterinary Science, 2023) López Ureña, Nadia María; Calero Bernal, Rafael; Vázquez Calvo, Ángela; Sánchez Sánchez, Roberto; Ortega Mora, Luis Miguel; Álvarez García, Gema
Toxoplasma gondii is a major foodborne zoonotic pathogen that can be transmitted through the consumption of raw or undercooked meat of small ruminants, among others. Serology has been suggested as an epidemiological indicator and several tests are available nowadays. However, there is no comparative study with the most used ones. Therefore, the objective of this study was to develop and validate two in-house tests (Western blot -TgSALUVET WB- and ELISA -TgSALUVET ELISA 2.0-) and perform a comparative study including such tests and four commercial ELISA kits (IDScreen®, PrioCHECK®, Pigtype® and IDEXX). First, a specific pattern of recognition of immunodominant antigens by TgSALUVET WB was determined with serum panels of noninfected sheep and sheep infected with T. gondii or Neospora caninum. Next, TgSALUVET WB was used as a reference to preliminary validate TgSALUVET ELISA 2.0 using sera from sheep and goats naturally infected with T. gondii. Then, the abovementioned sheep serum panels were analyzed by all tests and subjected to TG-ROC analyses and agreement tests, and cross-reactivity with the anti-N. caninum IgGs was studied. All the techniques were accurate enough for the cutoff values initially suggested with all serum panels (Se and Sp ≥ 94%), except for PrioCHECK®, which showed 83% Sp. However, a cutoff readjustment improved their diagnostic performance. Additionally, cross-reactions between anti-N. caninum antibodies and T. gondii antigens were detected with all tests. Thus, a second cutoff readjustment was carried out and the use of both readjusted cutoff values is recommended to obtain comparable data and avoid false-positive results.
Assessment of the Activity of Decoquinate and Its Quinoline-O-Carbamate Derivatives against Toxoplasma gondii In Vitro and in Pregnant Mice Infected with T. gondii Oocysts
(Molecules, 2021) Ramseier, Jessica; Imhof, Dennis; Anghel, Nicoleta; Hänggeli, Kai; Beteck, Richard M.; Ortega Mora, Luis Miguel; Balmer, Vreni; Sánchez Sánchez, Roberto; Ferré Pérez, Ignacio; Haynes, Richard K.; Hemphill, Andrew
The quinolone decoquinate (DCQ) is widely used in veterinary practice for the treatment of bacterial and parasitic infections, most notably, coccidiosis in poultry and in ruminants. We have investigated the effects of treatment of Toxoplasma gondii in infected human foreskin fibroblasts (HFF) with DCQ. This induced distinct alterations in the parasite mitochondrion within 24 h, which persisted even after long-term (500 nM, 52 days) treatment, although there was no parasiticidal effect. Based on the low half-maximal effective concentration (IC50) of 1.1 nM and the high selectivity index of >5000, the efficacy of oral treatment of pregnant mice experimentally infected with T. gondii oocysts with DCQ at 10 mg/kg/day for 5 days was assessed. However, the treatment had detrimental effects, induced higher neonatal mortality than T. gondii infection alone, and did not prevent vertical transmission. Thus, three quinoline-O-carbamate derivatives of DCQ, anticipated to have better physicochemical properties than DCQ, were assessed in vitro. One such compound, RMB060, displayed an exceedingly low IC50 of 0.07 nM, when applied concomitantly with the infection of host cells and had no impact on HFF viability at 10 µM. As was the case for DCQ, RMB060 treatment resulted in the alteration of the mitochondrial matrix and loss of cristae, but the changes became apparent at just 6 h after the commencement of treatment. After 48 h, RMB060 induced the expression of the bradyzoite antigen BAG1, but TEM did not reveal any other features reminiscent of bradyzoites. The exposure of infected cultures to 300 nM RMB060 for 52 days did not result in the complete killing of all tachyzoites, although mitochondria remained ultrastructurally damaged and there was a slower proliferation rate. The treatment of mice infected with T. gondii oocysts with RMB060 did reduce parasite burden in non-pregnant mice and dams, but vertical transmission to pups could not be prevented.
A new inactivated Tritrichomonas foetus vaccine that improves genital clearance of the infection and calving intervals in cattle
(Frontiers in Veterinary Science, 2022) Rojo-Montejo, Silvia; Román-Trufero, Alicia; Montenegro-Gregorio, Dolores; Puentes-Colorado, Eugenia; Parra-Romero, Alberto; Regidor-Cerrillo, Javier; Osoro, Koldo; Ortega Mora, Luis Miguel; Sánchez Sánchez, Roberto; Collantes Fernández, Esther
Bovine trichomonosis is a sexually transmitted disease that is a primary cause of early reproductive failure in cattle. The aim of the present study was to develop a vaccine formulation based on Tritrichomonas foetus trophozoites inactivated by lyophilization and Quil-A-adjuvanted. The safety, immunogenicity and efficacy of this new vaccine formulation (Trichobovis®) administered by two routes (subcutaneous: SC, and intravulvar: IVU) were compared with a commercial vaccine (TrichGuard®) in a well-established experimental bovine model of genital T. foetus infection. The new vaccine was considered safe in cattle because only mild local reactions were found in the vaccination area, which disappeared 3 weeks after administration. Cows immunized with Trichobovis cleared the infection faster than the non-immunized/challenged group (27–28 vs. 60 days; P < 0.05). Not significant differences were observed with the commercial vaccine respect to the positive control group, or between SC and IVU routes. The new vaccine stimulated high serum anti-T. foetus IgG and genital IgA levels and generated an IgG booster effect similar to TrichGuard. IgA levels were associated with significantly earlier genital clearance of T. foetus in cows immunized with Trichobovis by SC route (G1A) or TrichGuard (G2). The strongest association was found in the group G1A on day 14 post-infection (p.i.) (r = −0.74) and in G2 on day 35 p.i. (r = −0.71). The efficacy of vaccination using Trichobovis on the reproductive performance was also investigated under field conditions in a herd where T. foetus was present. The calving intervals were significantly reduced by 45.2 days (P < 0.05), calves were born 28 days earlier (P < 0.05) and an increase of 8.7% in the calving rate (P > 0.05) was observed in the vaccinated group. These results demonstrate that Trichobovis improved the reproductive performance under field conditions in herds where T. foetus infection is present.
A questionnaire-based survey in Spain provides relevant information to improve the control of ovine coccidiosis
(Frontiers in Veterinary Science, 2023) Sánchez Sánchez, Roberto; Gutiérrez, Jorge; Blasco Castello, José Luis; Marcos Santamaría, María; Cano Alsua, Santiago; Elvira, Laura; Ferré Pérez, Ignacio; Ortega Mora, Luis Miguel
Ovine coccidiosis is a widespread intestinal parasitic disease caused by Eimeria spp. Lambs are infected by the ingestion of sporulated oocysts, experiencing diarrhea and low growth rates. Control should be based on measures to reduce infection pressure and stress on the animals as well as on appropriate diagnosis and strategic treatment. To obtain information on how control measures are implemented in the ovine sector in Spain, a questionnaire-based survey was completed in 2022 by 154 veterinarians and 173 farmers working in this sector. Coccidiosis was highlighted as a relevant disease by 34% of the respondents. The period of greatest risk seemed to differ between production systems, being mainly early after weaning (7–15 days after weaning) in meat flocks and feedlots and later (1–2 months after weaning) in dairy flocks. The absence of cleaning and disinfection measures was identified as a risk factor by 51% of the veterinarians, with 22% mentioning overcrowding of animals and 22% indicating that coccidiosis has more incidence in flocks with large number of animals. The use of laboratory diagnosis methods (fecal oocyst count) was unusual in 70 and 84% of the veterinarians and farmers, respectively. Regarding control, dairy flocks usually housed a larger number of animals under intensive conditions, and they implemented more frequently control measures for coccidiosis than meat flocks. Anticoccidial drugs were used in 79% of the flocks, and in 74–82% of them, they were applied based on clinical criteria. Comparing protocols for anticoccidial treatment among different production systems, in meat flocks, anticoccidial drugs were applied more frequently when clinical signs were observed, and coccidiostats were used for less than 28 days compared to dairy flocks. These results highlight the need for improvement in the use of anticoccidial treatments adjusted to the new regulatory framework in the EU, which in turn will rationalize the use of antimicrobial compounds and may help to mitigate the impact of coccidiosis in flocks.
An Early Treatment With BKI-1748 Exhibits Full Protection Against Abortion and Congenital Infection in Sheep Experimentally Infected With Toxoplasma gondii
(The Journal of Infectious Diseases, 2023) Sánchez Sánchez, Roberto; Imhof, Dennis; Hecker, Yanina Paola; Ferré Pérez, Ignacio; Re, Michela Tatiana; Moreno Gonzalo, Javier; Blanco Murcia, Francisco Javier; Mejías López, Elena; Hulverson, Matthew A.; Choi, Ryan; Arnold, Samuel L. M.; Ojo, Kayode K.; Barrett, Lynn K.; Hemphill, Andrew; Van Voorhis, Wesley C.; Ortega Mora, Luis Miguel
Congenital toxoplasmosis in humans and in other mammalian species, such as small ruminants, is a well-known cause of abortion and fetal malformations. The calcium-dependent protein kinase 1 (CDPK1) inhibitor BKI-1748 has shown a promising safety profile for its use in humans and a good efficacy against Toxoplasma gondii infection in vitro and in mouse models. Ten doses of BKI-1748 given every other day orally in sheep at 15 mg/kg did not show systemic or pregnancy-related toxicity. In sheep experimentally infected at 90 days of pregnancy with 1000 TgShSp1 oocysts, the BKI-1748 treatment administered from 48 hours after infection led to complete protection against abortion and congenital infection. In addition, compared to infected/untreated sheep, treated sheep showed a drastically lower rectal temperature increase and none showed IgG seroconversion throughout the study. In conclusion, BKI-1748 treatment in pregnant sheep starting at 48 hours after infection was fully effective against congenital toxoplasmosis.