Person:
Sánchez Sánchez, Roberto

Loading...
Profile Picture
First Name
Roberto
Last Name
Sánchez Sánchez
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Veterinaria
Department
Sanidad Animal
Area
Identifiers
UCM identifierScopus Author IDDialnet ID

Search Results

Now showing 1 - 10 of 12
  • Item
    A systematic review and meta-analysis of the serological diagnosis of Toxoplasma gondii infection highlight the lack of a One Health integrative research
    (Research in Veterinary Science, 2023) Huertas López, Ana; Álvarez García, Gema; Sánchez Sánchez, Roberto; Cantos Barreda, Ana; Ibáñez López, Francisco Javier; Martínez Subiela, Silvia; Cerón, José Joaquín; Martínez-Carrasco, Carlos
    Toxoplasma gondii is a globally distributed food-borne zoonotic parasite with numerous infection sources. The control of this zoonosis requires a One Health response that partially depends on serological monitoring in humans and animals. Herein, a systematic review and a meta-analysis were performed to analyse and compare the transdisciplinary and integrative research under the One Health approach. We searched for articles published between January 1st 2014 and September 5th 2022, focused on the development and evaluation of serological techniques for the diagnosis of T. gondii infection in humans and animals. After an exhaustive search on three scientific databases, a quality assessment was performed on 291 articles by QUADAS-2 tool, and 113 articles were finally selected. A total of 18 variables were extracted and analysed, including bibliometric characteristics, study aims and methodology. Remarkably, none of the studies included in the meta-analysis explicitly quoted the words “One Health”, and only 23.9% of them alluded to the principles underlying the One Health approach; in particular, none were conducted by physician-only teams, with the majority of these studies involving interdisciplinary research teams, followed by veterinarians and by non-physician or non-veterinarian researchers. The One Health approach followed in the serodiagnosis of T. gondii still needs further integration among scientific disciplines, which is essential to design effective control strategies.
  • Item
    Efficacy of the bumped kinase inhibitor BKI-1708 against the cyst-forming apicomplexan parasites Toxoplasma gondii and Neospora caninum in vitro and in experimentally infected mice
    (International Journal for Parasitology: Drugs and Drug Resistance, 2024) Ferreira de Sousa, Maria Cristina; Imhof, Dennis; Hänggeli, Kai Pascal Alexander; Choi, Ryan; Hulverson, Matthew A.; Arnold, Samuel L. M.; Van Voorhis, Wesley C.; Fan, Erkang; Sánchez Sánchez, Roberto; Ortega Mora, Luis Miguel; Hemphill, Andrew
    Toxoplasma gondii and Neospora caninum are major worldwide morbidity-causing pathogens. Bumped kinase inhibitors (BKIs) are a compound class that has been optimized to target the apicomplexan calcium-dependent protein kinase 1 (CDPK1) – and several members of this class have proven to be safe and highly active in vitro and in vivo. BKI-1708 is based on a 5-aminopyrazole-4-carboxamide scaffold, and exhibited in vitro IC50 values of 120 nM for T. gondii and 480 nM for N. caninum β-galactosidase expressing strains, and did not affect human foreskin fibroblast (HFF) viability at concentrations up to 25 μM. Electron microscopy established that exposure of tachyzoite-infected fibroblasts to 2.5 μM BKI-1708 in vitro induced the formation of multinucleated schizont-like complexes (MNCs), characterized by continued nuclear division and harboring newly formed intracellular zoites that lack the outer plasma membrane. These zoites were unable to finalize cytokinesis to form infective tachyzoites. BKI-1708 did not affect zebrafish (Danio rerio) embryo development during the first 96 h following egg hatching at concentrations up to 2 μM. Treatments of mice with BKI-1708 at 20 mg/kg/day during five consecutive days resulted in drug plasma levels ranging from 0.14 to 4.95 μM. In vivo efficacy of BKI-1708 was evaluated by oral application of 20 mg/kg/day from day 9–13 of pregnancy in mice experimentally infected with N. caninum (NcSpain-7) tachyzoites or T. gondii (TgShSp1) oocysts. This resulted in significantly decreased cerebral parasite loads and reduced vertical transmission in both models without drug-induced pregnancy interference.
  • Item
    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.
  • Item
    Ovine placental explants: a new ex vivo model to study host‒pathogen interactions in reproductive pathogens
    (Theriogenology, 2023) Horcajo Iglesias, María Del Pilar; Ortega Mora, Luis Miguel; Benavides, Julio; Sánchez Sánchez, Roberto; Ammieva, Rafael; Collantes Fernández, Esther; Pastor Fernández, Iván
    Reproductive failure is one of the main performance constraints in ruminant livestock. Transmissible agents such as Toxoplasma gondii and Neospora caninum are commonly involved in the occurrence of abortion in ruminants, but little is known about the mechanisms involved. While in vivo models are optimal for the study of abortion pathogenesis, they have a high economic cost and come with ethical concerns. Unfortunately, alternative in vitro models fail to replicate the complex in vivo placental structure. To overcome the limitations of currently available models, we developed an ex vivo model based on the cultivation of fresh and cryopreserved sheep placental explants, enabling the biobanking of tissues. Reproducible and simple markers of tissue integrity (histology, RNA concentrations), viability (resazurin reduction), and functionality (synthesis of steroid hormones) were also investigated, allowing a clear quality assessment of the model. This work shows that, similar to fresh explants, tissues cryopreserved in ethylene glycol using slow freezing rates maintain not only their structure and function but also their receptivity to T. gondii and N. caninum infection. In addition, the findings demonstrate that explant lifespan is mainly limited by the culture method, with protocols requiring improvements to extend it beyond 2 days. These findings suggest that cryopreserved tissues can be exploited to study the initial host‒pathogen interactions taking place in the placenta, thus deepening the knowledge of the specific mechanisms that trigger reproductive failure in sheep. Importantly, this work paves the way for the development of similar models in related species and contributes to the reduction of experimental animal use in the future.
  • Item
    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.
  • Item
    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.
  • Item
    Dynamics of Neospora caninum-Associated Abortions in a Dairy Sheep Flock and Results of a Test-and-Cull Control Programme
    (Pathogens, 2021) Sánchez Sánchez, Roberto; Vázquez Calvo, Ángela; Fernández Escobar, Mercedes; Regidor Cerrillo, Javier; Benavides, Julio; Gutiérrez, Jorge; Gutierrez Expósito, Daniel; Crespo Ramos, Francisco José; Ortega Mora, Luis Miguel; Álvarez García, Gema
    Neospora caninum is an apicomplexan parasite that can cause abortions and perinatal mortality in sheep. Although ovine neosporosis has been described worldwide, there is a lack of information about the relationship between N. caninum serostatus and the reproductive performance. In this study, we described the infection dynamics in a dairy sheep flock with an abortion rate up to 25% and a N. caninum seroprevalence of 32%. Abortions were recorded in 36% and 9% of seropositive and seronegative sheep, respectively. Seropositive sheep were more likely to abort twice (OR = 4.44) or three or more times (OR = 10.13) than seronegative sheep. Endogenous transplacental transmission was the main route of transmission since 86% of seropositive sheep had seropositive offspring. Within dams that had any abortion, seropositive sheep were more likely than seronegative ones to have female descendants that aborted (OR = 8.12). The slight increase in seropositivity with the age, the low percentage of animals with postnatal seroconversion or with low avidity antibodies, and the seropositivity of one flock dog, indicated that horizontal transmission might have some relevance in this flock. A control programme based on selective culling of seropositive sheep and replacement with seronegative animals was effective in reducing the abortion rate to 7.2%.
  • Item
    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.
  • Item
    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.
  • Item
    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.