Publicaciones LAE

In vitro and in vivo anticancer effects of two quinoline–platinum(II) complexes on human osteosarcoma models

2022-02-17T04:04:38Z

Articulo Cancer Chemotherapy and Pharmacology; vol. 83, no. 4 Platinum-based drugs, mainly cisplatin, are used for the treatment of several solid tumors such as OS. However, cisplatin treatment often results in the development of chemoresistance, leading therapeutic failure. We have previously reported that platinum complexes containing 8-hydroxyquinoline ligands have good antitumor activity against different cancer cell lines and with a different and better cytotoxic profile than cisplatin. Here, the anticancer properties of two different quinoline–platinum complexes [Pt(Cl)₂(quinoline)(dmso)] (1) [PtCl(8-O-quinoline)(dmso)] (2) on in vitro (2D and 3D) and in vivo models (xenograft tumor of human osteosarcoma in mice) are presented. In this order, [PtCl(8-O-quinoline)(dmso)] (2) impaired cell viability to have a more pronounced antitumor effect than cisplatin on MG-63 osteosarcoma cells (IC₅₀ 4 µM vs. 39 µM). Besides, [PtCl(8-O-quinoline)(dmso)] (2) increased ROS production in a dose-manner response and this compound induced early and late apoptotic fractions of human osteosarcoma cells. Finally, [PtCl(8-O-quinoline)(dmso)] (2) decreased the cell viability of multicellular spheroids and reduced the tumor volume on athymic nude mice N:NIH(S) Fox1^nu without inducing side effects. In this way, [PtCl(8-O-quinoline)(dmso)] (2) did not alter the normal cytoarchitecture of liver and kidney and the blood biomarkers (GPT, GOT, uremia, and creatinine) did not suffer modifications. Taken together, our data indicate that these compounds showed a better anticancer performance than cisplatin on in vitro and in vivo studies. These results showed the importance of chelation in the antitumor properties, suggesting that the [PtCl(8-O-quinoline)(dmso)] (2) might be a promising agent for the treatment of human osteosarcoma tumors resistant to cisplatin.

Desarrollo de un esterilizador de aire UV-C para el control de la transmisión aérea del COVID-19

2020-12-14T20:03:18Z

Articulo Development of a UV-C air sterilizer for the control of the air transmission of COVID-19 Innovación y Desarrollo Tecnológico y Social (IDTS); vol. 2, no. 2, número especial COVID-19 En el contexto de la pandemia por COVID-19, y considerando que existe una transmisión área del virus, que la OMS tardó en reconocer, pero que hoy está comprobado, decidimos desarrollar un Esterilizador de Aire con una combinación específica de Filtros Especiales y el uso de Luz UV-C. Luego del desarrollo del esterilizador (Belerofonte I), se realizaron pruebas biológicas, con Virus, Bacterias, Hongos y Esporas, para ver su efectividad en esterilizar ambientes. Luego de los resultados contundentes obtenidos, y de las pruebas de flujo de aire realizadas en Ingeniería, el equipo se escaló a un tamaño más pequeño, logrando las mismas prestaciones (Belerofonte II). Con el segundo prototipo se repitieron las pruebas, mostrando la misma efectividad. Si bien el desarrollo se enmarca en la pandemia por COVID-19, sería de utilidad a largo plazo, dadas sus prestaciones, para evitar infecciones intrahospitalarias, y que podría ser aplicable a consultorios, transporte público, locales comerciales, entre otros.; In the context of the COVID-19 pandemic, and considering that there is an airborne transmission of the virus, which the WHO was slow to recognize, but is now proven, we decided to develop an Air Sterilizer with a specific combination of Special Filters and the use UV-C Light. After the development of the sterilizer (Belerofonte I), biological tests were carried out with Viruses, Bacteria, Fungi and Spores, to see its effectiveness in sterilizing environments. After the strong results obtained, and the air flow tests carried out in Engineering, the equipment was scaled to a smaller size, with the same performance (Belerofonte II). The tests were repeated with the second prototype, showing the same effectiveness. Although the development is a part to fight the COVID-19 pandemic, it would be useful in the long term, given its benefits, to avoid intra-hospital infections, and it could be applicable to clinics, public transport, and commercial premises, among others. Financiamiento: UNLP – Incubadora de Proyectos Minerva

Membrane vesicles derived from Bordetella bronchiseptica: active constituent of a new vaccine against infections caused by this pathogen

2020-09-14T20:06:10Z

Articulo Applied and Environmental Microbiology; vol. 84, no. 4 Bordetella bronchiseptica, a Gram-negative bacterium, causes chronic respiratory tract infections in a wide variety of mammalian hosts, including humans (albeit rarely). We recently designed Bordetella pertussis and Bordetella parapertussis experimental vaccines based on outer membrane vesicles (OMVs) derived from each pathogen, and we obtained protection against the respective infections in mice. Here, we demonstrated that OMVs derived from virulent-phase B. bronchiseptica (OMVBbvir⁺) protected mice against sublethal infections with different B. bronchiseptica strains, two isolated from farm animals and one isolated from a human patient. In all infections, we observed that the B. bronchiseptica loads were significantly reduced in the lungs of vaccinated animals; the lung-recovered CFU were decreased by ≥4 log units, compared with those detected in the lungs of nonimmunized animals (P < 0.001). In the OMVBbvir⁺-immunized mice, we detected IgG antibody titers against B. bronchiseptica whole-cell lysates, along with an immune serum having bacterial killing activity that both recognized B. bronchiseptica lipopolysaccharides and polypeptides such as GroEL and outer membrane protein C (OMPc) and demonstrated an essential protective capacity against B. bronchiseptica infection, as detected by passive in vivo transfer experiments. Stimulation of cultured splenocytes from immunized mice with OMVBbvir⁺ resulted in interleukin 5 (IL-5), gamma interferon (IFN-γ), and IL-17 production, indicating that the vesicles induced mixed Th2, Th1, and Th17 T-cell immune responses. We detected, by adoptive transfer assays, that spleen cells from OMVBbvir⁺-immunized mice also contributed to the observed protection against B. bronchiseptica infection. OMVs from avirulent-phase B. bronchiseptica and the resulting induced immune sera were also able to protect mice against B. bronchiseptica infection.

Outer-Membrane-Vesicle-Associated O Antigen, a Crucial Component for Protecting Against Bordetella parapertussis Infection

2020-09-14T20:06:20Z

Articulo Frontiers in Immunology; vol. 9 Bordetella parapertussis is a respiratory-disease pathogen producing symptomatology similar to that of pertussis but of underestimated incidence and with no specific vaccine existing. We recently designed a vaccine candidate from B. parapertussis outer-membrane vesicles (OMVs) that proved to be safe and protective in a murine-infection model. Based on protection recently reported for the B. parapertussis O antigen in aqueous solution, we assessed here whether the B. parapertussis O-antigen-containing lipopolysaccharide (BppLPS-O⁺) embedded in the membranes, as present in B. parapertussis-derived OMVs (OMVs(Bpp-LPS-O⁺)), was the component responsible for that previously observed protection by OMVs. By performing a comparative study with OMVs from a human strain with undetectable O antigen (OMVs(Bpp-LPS-O⁻)), we demonstrated that the OMVs(Bpp-LPS-O⁺), but not the OMVs(Bpp-LPS-O⁻), protected mice against sublethal B. parapertussis infections. Indeed, the B. parapertussis loads were significantly reduced in the lungs of OMVs(Bpp-LPS-O⁺) -vaccinated animals, with the CFUs recovered being decreased by 4 log units below those detected in the non-immunized animals or in the animals treated with the OMVs(Bpp-LPS-O⁻), (p < 0.001). We detected that the OMVs(Bpp-LPS-O⁺) induced IgG antibodies against B. parapertussis whole-cell lysates, which immunocomponents recognized, among others, the O antigen and accordingly conferred protection against B. parapertussis infection, as observed in in-vivo-passive-transfer experiments. Of interest was that the OMVs(Bpp-LPS-O⁺) -generated sera had opsonophagocytic and bactericidal capabilities that were not detected with the OMVs(Bpp-LPS-O⁻)-induced sera, suggesting that those activities were involved in the clearance of B. parapertussis. Though stimulation of cultured spleen cells from immunized mice with formulations containing the O antigen resulted in gamma interferon (IFN-γ) and interleukin-17 production, spleen cells from OMVs(Bpp-LPS-O⁺) -immunized mice did not significantly contribute to the observed protection against B. parapertussis infection. The protective capability of the B. parapertussis O antigen was also detected in formulations containing both the OMVs derived from B. pertussis and purified BppLPS-O⁺. This combined formulation protected mice against B. pertussis along with B. parapertussis.

Modelo de inmunodeficiencia: el ratón BALB/c.Cg-Fox1^nu

2020-11-07T20:06:52Z

Articulo Química Viva; año 10, no. 3 En los últimos 40 años, el desarrollo de modelos murinos ha posibilitado realizar avances trascendentes en el estudio y terapéutica de muchas enfermedades humanas y animales. Asimismo, el empleo de retrocruzas ha permitido crear ratones congénicos, como resultado de transferir una mutación a otra cepa. El objetivo de este trabajo fue desarrollar la línea congénica BALB/c.Cg-Fox1nu, introduciendo la mutación Fox1nu presente en la línea N:NIH(S) a la línea consanguínea BALB/c. Se aparearon ratones de ambas líneas para la producción de la línea congénica hasta la generación N10. Para ello se utilizaron retrocruzas seguidas de intercruzas y selección de ratones mutantes. La línea congénica BALB/c.Cg-Fox1nu incorporó la porción más pequeña del cromosoma donante portando la mutación Fox1nu. Esta nueva línea murina, actualmente disponible en el bioterio de la FCV UNLP (Universidad Nacional de la Plata), representa una importante herramienta en el campo de la inmunología, como modelo en oncología y para comparar estudios donde el ratón BALB/c es su homólogo inmunocompetente.

El ratón CBA/N xid como modelo animal de inmunodeficiencia: Producción y manejo

2020-11-07T20:06:57Z

Articulo Química Viva; año 9, no. 1 Uno de los hallazgos más importantes para la investigación biomédica lo constituye el descubrimiento y producción de nuevas cepas de ratones inmunodeficientes. Una de ellas es la del ratón CBA/N xid (xid: Xlinked inmunodeficiency) que presenta una mutación recesiva y ligada al sexo en el gen de la tirosin-kinasa de Bruton (btk), homóloga tanto en ratón como en el hombre. Por su condición de inmunodeficientes y libres de patógenos específicos (SPF), deben mantenerse en ambientes bajo barreras sanitarias estrictas. En estos animales las células B muestran defectos en su maduración y se encuentran en un número reducido en la sangre periférica. Debido a sus características se pudo probar la existencia de dos grupos de células B en los ratones normales por lo que esta cepa se utiliza en estudios sobre inmunología e inflamación. Es el modelo animal adecuado para investigaciones relacionadas con la inmunodeficiencia humana ligada al cromosoma X, HIV y terapia génica. Incorporándole el gen nude se utiliza como modelo para estudios de tumores humanos. Esta cepa representa una importante herramienta que se podrá utilizar en medicina experimental cuando se necesite investigar la base molecular, la fisiopatología o nuevas terapias en las enfermedades y alteraciones mencionadas.

El ratón nude (nu/nu) como modelo animal de inmunodeficiencia

2020-11-07T20:07:00Z

Articulo Química Viva; año 5, no. 1 La especie animal más utilizada en experimentación científica en la actualidad es el ratón (Mus musculus). Esto se debe principalmente no solo a sus características reproductivas, su tamaño y la facilidad de manejo, sino también a que su genoma es totalmente conocido. Esto ultimo ha permitido el desarrollo de modelos animales que pueden reproducir características específicas o enfermedades del hombre y de los animales convirtiéndose en reactivos biológicos sobre los cuales se pueden extrapolar los resultados de las investigaciones. Actualmente la producción de modelos murinos constituye una de las temáticas de vanguardia dentro de la ciencia de los animales de laboratorio.

Potential therapeutic targets for growth arrest of colorectal cancer cells exposed to PTHrP

2020-11-07T20:07:54Z

Preprint Molecular and Cellular Endocrinology; vol. 478 Although PTHrP is implicated in several cancers, its role in chemoresistance is not fully elucidated. We found that in CRC cells, PTHrP exerts proliferative and protective effects and induces cell migration. The aim of this work was to further study the effects of PTHrP in CRC cells. Herein we evidenced, for the first time, that PTHrP induces resistance to CPT-11 in Caco-2 and HCT116 cells; although both cell lines responded to the drug through different molecular mechanisms, the chemoresistance by PTHrP in these models is mediated through ERK, which in turn is activated by PCK, Src and Akt. Moreover, continue administration of PTHrP in nude mice xenografts increased the protein levels of this MAPK and of other markers related to tumorigenic events. The understanding of the molecular mechanisms leading to ERK 1/2 activation and the study of ERK targets may facilitate the development of new therapeutic strategies for CRC treatment.

Prevalencia del virus diminuto del ratón, determinada mediante una técnica de PCR semianidada, en ratones de experimentación de bioterios de Argentina

2020-07-02T20:02:27Z

Articulo Prevalence of infections produced by the minute virus of mice, determined by heminested PCR, in mice of conventional facilities of Argentina Analecta Veterinaria; vol. 40, no. 1 El virus diminuto del ratón puede producir alteraciones de los parámetros fisiológicos de los animales infectados, lo que hace que se modifiquen los resultados de aquellas experiencias en las que el ratón es utilizado como modelo experimental. Para poner en práctica medidas adecuadas de control del virus en bioterios, son necesarios métodos de detección eficientes, ya sea técnicas serológicas que ponen en evidencia la presencia de anticuerpos antivirales en el huésped, o técnicas moleculares como la PCR. El objetivo de este trabajo fue diseñar y poner a punto una técnica de PCR semianidada para la detección de ADN viral a partir de muestras de materia fecal y de bazo y, determinar, mediante esta técnica molecular, la prevalencia del virus en bioterios de Argentina. Diecinueve muestras de pools de heces (del 41,3 % de los bioterios) y 109 muestras de bazo (del 47,82 % de los bioterios) resultaron positivas. La prevalencia a partir del análisis total de las muestras de bazo fue estimada en 23,69 %. La técnica de PCR semianidada diseñada, constituye una herramienta molecular sensible y específica para realizar la detección del virus diminuto del ratón en instalaciones de animales de experimentación de Argentina.; The minute virus of mice may alter physiological parameters of infected animals, which can lead to modifications in research results when mice are used as an experimental model. Efficient detection methods are necessary to implement adequate virus control measures in mice facilities, either by serological techniques that reveal the presence of antiviral antibodies in the host, or by molecular techniques such as PCR. The purpose of this study was to design and standardize a heminested PCR technique to detect viral DNA from stool and spleen samples and to determine the prevalence of the virus in conventional mice facilities of Argentina by this molecular technique. Nineteen pools of stool (from 41.3 % of conventional facilities) and 109 spleens (from 47.82 % of conventional facilities) were positive. The prevalence from the total analysis of the spleen samples was estimated at 23.69 %. The designed heminested PCR was sensitive and specific and allows the detection of minute virus of mice in experimental mice facilities of Argentina.

Nuevos datos sobre la distribución de Irenomys tarsalis (Philippi, 1900) (Rodentia: Sigmodontinae) en Argentina

2020-09-13T04:07:00Z

Articulo New data on the geographic distribution of Irenomys tarsalis (Philippi, 1900) (Rodentia: Sigmodontinae) in Argentina Mastozoología Neotropical; vol. 11, no. 1 Se brinda una síntesis de las localidades conocidas en Argentina para el roedor sigmodontino Irenomys tarsalis , adicionando los registros más extremos hacia el norte (Pilolil, 39º 38’ 60” S, 70º 57’ 00” O, Catán Lil, Neuquén) y hacia el sur (44º 49’ 25” S, 72º 00’ 26” O, Río Senguerr, Chubut).; We summarize the known Argentinean localities for this sigmodontine, adding the northernmost (Pilolil, 39º 38’ 60” S, 70º 57’ 00” W, Catán Lil, Neuquén) and southernmost (44º 49’ 25” S, 72º 00’ 26” W, Río Senguerr, Chubut) records.

Indirect ELISA (iELISA) for routine detection of antibodies against Minute Virus of Mice (MVM) in mice colonies

2020-11-08T04:07:47Z

Comunicacion ELISA indirecto (iELISA) para la detección de rutina de anticuerpos contra el virus diminuto del ratón (MVM) en colonias de ratones Revista Argentina de Microbiología; vol. 49, no. 3 In this study we developed an indirect ELISA to detect antibodies against Minute Virus of Mice (MVM) using an antigen produced from BHK-21 cells infected with a prototype strain of the virus. The optimal antigen concentration and serum dilutions were established. In order to analyze variability in the laboratory, reproducibility and repeatability within and between plates were determined. Then, a panel of 460 sera from conventional facilities and previously classified as positive or negative by the indirect fluorescent antibody assay was analyzed. The cutoff value was determined by a receiver operating characteristic (ROC) curve. The results of the indirect ELISA were compared with those of the indirect fluorescent antibody assay. The ELISA assay showed 100% sensitivity and 99% specificity. ELISA is a useful tool to be developed in standard virology laboratories and can be used for screening animals faster than the traditional indirect fluorescent antibody assay.; Se desarrolló un ELISA indirecto para detectar anticuerpos contra el virus diminuto del ratón (Mice minute virus [MVM]), utilizando un antígeno producido a partir de células BHK-21 infectadas con la cepa prototipo del virus. Se establecieron las diluciones óptimas de antígeno y el suero a utilizar. Para analizar la variabilidad en el laboratorio, se determinaron la reproducibilidad y la repetibilidad dentro de una placa y entre placas. Luego se analizaron 460 sueros provenientes de bioterios convencionales y clasificados previamente como positivos o negativos por inmunofluorescencia indirecta. El valor de corte se determinó mediante una curva ROC. Los resultados se compararon con los obtenidos con la prueba de inmunofluorescencia indirecta. El ELISA mostró 100% de sensibilidad y un 99% de especificidad. Esta técnica demostró ser una herramienta útil para desarrollar en laboratorios de virología estándar y puede utilizarse como prueba tamiz para seleccionar animales de manera más rápida que con la tradicional prueba de inmunofluorescencia indirecta.

Impacto del desarrollo de la línea tumoral A549 en el bienestar de ratones de la cepa N:NIH(S)-Fox1^nu

2020-10-31T20:07:26Z

Tesis de doctorado Carbone, Cecilia; Ayala, Miguel Ángel; Ferrari, Ricardo; García Mitacek, María Carla; Saldaña, Jenny Carolina Doctor en Ciencias Veterinarias; Universidad Nacional de La Plata Las Ciencias del Bienestar Animal y de los Animales de Laboratorio se asocian ineludiblemente, para evaluar científicamente cómo los procedimientos experimentales y las condiciones de alojamiento impactan sobre la calidad de vida de los animales. En particular en investigación oncológica, se han redactado guías de recomendaciones pero éstas fallan en describir cómo se pueden discernir alteraciones sutiles en el bienestar. De esta forma, el objetivo principal consistió en determinar el impacto de la línea tumoral humana A549 en el bienestar de ratones del stock NLAE:NIH(S)-Fox1nu trasplantados con la misma y en evaluar el efecto del enriquecimiento ambiental sobre el desarrollo tumoral. Para alcanzarlo se evaluó por un lado la fisiología de los ratones a través de la concentración de los metabolitos de la corticosterona en materia fecal, de cambios en la condición corporal y del análisis de parámetros sanguíneos y por el otro las frecuencias de comportamientos espontáneos que realizaron en la caja donde habitaban normalmente y la performance en distintas pruebas de comportamiento. Además, para poder alcanzar dichos objetivos se desarrollaron dos nuevas metodologías: una técnica de medición de los tumores subcutáneos no aversiva y una prueba para para evaluar el sesgo en el juicio ante un estímulo ambiguo. En líneas generales, no se evidenciaron alteraciones significativas en los parámetros de fisiología y de comportamiento que indicarían una alteración severa en el bienestar de los ratones. Sin embargo, sí se manifestaron algunas modificaciones sutiles que convalidan la interpretación de que el trasplante tumoral no es un procedimiento inocuo para estos animales. Con respecto al enriquecimiento ambiental, resultó llamativa la diferencia en el desarrollo tumoral entre machos y hembras por lo que se postuló que la inhibición del desarrollo tumoral se debió al estrés asociado al aumento de los comportamientos agonistas en la caja como consecuencia del enriquecimiento ambiental y no por dicha modificación ambiental.; Animal Welfare and Laboratory Animal Sciences are inevitably associated, to assess scientifically how experimental procedures and husbandry affect the animals’ quality of life. Guidelines for oncologic research have been written, but these generally fail to describe subtle changes in welfare. Hence, the main objective was to assess the impact of tumor development in the welfare of NLAE:NIH(S)-Fox1nu mice transplanted with A549 cells and to evaluate the effect of environmental enrichment in tumor development. The physiology was assessed through the quantification of corticosterone metabolites in feces, body condition scoring and blood parameters and the behavior by means of behavioral tests as well as analyzing the frequency of home cage behaviors. In addition, to meet the objectives two new methodologies were described: a non-aversive photographic measurement method for subcutaneous tumors and an assay to assess judgment bias when exposed to an ambiguous stimulus. Altogether, severe alterations in the physiology and the behavior which would indicate a reduction in the animals’ welfare were not detected. Nevertheless, subtle behavioral modifications were observed by which it was assumed that tumor development did generate a subtle malaise sensation to the animals. With regards to environmental enrichment, an interesting difference in tumor development between males and females was observed, and it was hypothesized that this difference was due to stress associated to an increase of agonistic behaviors in the home cage as a consequence of environmental enrichment.

Evaluation of an indirect enzyme-linked immunosorbent assay for routine screening of Theiler's murine encephalomyelitis virus antibodies in mice colonies

2020-11-08T20:09:18Z

Articulo Journal of Veterinary Diagnostic Investigation; vol. 20, no. 6 The current study demonstrates the ability of an indirect enzyme-linked immunosorbent assay (iELISA) to detect antibodies against Theiler's murine encephalomyelitis virus in mice colonies. The antigen was produced from infected baby hamster kidney (BHK)-21 cells and treated with 1% Nonidet P40 in saline buffer. Control antigen was prepared following the same procedure using uninfected BHK-21 cells. The optimal antigen and serum dilutions were established. The reaction was revealed using an anti-mousehorseradish peroxidase conjugate and 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid). Optimized iELISA was validated by detection of antibodies in known positive and negative serum samples before testing the samples of unknown status. Performance of the iELISA was compared with the indirect fluorescent antibody test, and the cutoff value was determined by receiver operating curve. Indirect ELISA showed 100% sensitivity, 99.38% specificity, and 97.78% predictive positive value. The antigen used is easy to produce, and no special equipment is required. The iELISA developed is simple and provides a rapid and less costly tool for diagnosis and research.

Targeting tumor-associated macrophages and inhibition of MCP-1 reduce angiogenesis and tumor growth in a human melanoma xenograft

2020-11-09T04:06:48Z

Articulo Journal of Investigative Dermatology; vol. 127, no. 8 Chemokines such as monocyte chemoattractant protein (MCP)-1 are key agonists that attract macrophages to tumors. In melanoma, it has been previously shown that variable levels of MCP-1/CCL2 appear to correlate with infiltrating macrophages and tumor fate, with low to intermediate levels of the chemokine contributing to melanoma development. To work under such conditions, a poorly tumorigenic human melanoma cell line was transfected with an expression vector encoding MCP-1. We found that M2 macrophages are associated to MCP-1⁺ tumors, triggering a profuse vascular network. To target the protumoral macrophages recruitment and reverting tumor growth promotion, clodronate-laden liposomes (Clod-Lip) or bindarit were administered to melanoma-bearing mice. Macrophage depletion after Clod-Lip treatment induced development of smaller tumors than in untreated mice. Immunohistochemical analysis with an anti-CD31 antibody revealed scarce vascular structures mainly characterized by narrow vascular lights. Pharmacological inhibition of MCP-1 with bindarit also reduced tumor growth and macrophage recruitment, rendering necrotic tumor masses. We suggest that bindarit or Clod-Lip abrogates protumoral-associated macrophages in human melanoma xenografts and could be considered as complementary approaches to antiangiogenic therapy.

An atypical clinical presentation for the first isolation of Canid herpesvirus 1 in Argentina

2020-10-31T04:07:43Z

Comunicacion Uma apresentação clínica atípica para o primeiro isolamento do herpesvirus canino 1 na Argentina Arquivo Brasileiro de Medicina Veterinaria e Zootecnia; vol. 62, no. 5 Canid herpesvirus 1 (CaHV-1) is a Varicellovirus of the subfamily Alphaherpesvirinae, family Herpesviridae, and order Herpesvirales, with a host range restricted to domestic and wild canids (Remond et al., 1996). CaHV-1 was first recognized as the agent responsible for causing a highly fatal hemorrhagic viral disease in newborn puppies in 1965. Apart from being an important disease in newborn puppies, CaHV-1 also affects reproduction of dogs in other ways: the virus may cause vesicular lesions in the vestibulum and vagina of the bitch, as well as on the penis and the preputial mucosa of dogs and may cause embryonic resorption, abortion, and fetal death (Carmichael, 1970).

A recombinant iron transport protein from Bordetella pertussis confers protection against Bordetella parapertussis

2020-05-20T04:08:45Z

Articulo Microbiology and Immunology; vol. 61, no. 10 Whooping cough, which is caused by Bordetella pertussis and B. parapertussis, is a reemerging disease. New protective antigens are needed to improve the efficacy of current vaccines against both species. Using proteomic tools, it was here found that B. parapertussis expresses a homolog of AfuA, a previously reported new vaccine candidate against B. pertussis. It was found that this homolog, named AfuABpp, is expressed during B. parapertussis infection, exposed on the surface of the bacteria and recognized by specific antibodies induced by the recombinant AfuA cloned from B. pertussis (rAfuA). Importantly, the presence of the O-antigen, a molecule that has been found to shield surface antigens on B. parapertussis, showed no influence on antibody recognition of AfuABpp on the bacterial surface. The present study further showed that antibodies induced by immunization with the recombinant protein were able to opsonize B. parapertussis and promote bacterial uptake by neutrophils. Finally, it was shown that this antigen confers protection against B. parapertussis infection in a mouse model. Altogether, these results indicate that AfuA is a good vaccine candidate for acellular vaccines protective against both causative agents of whooping cough.

Narrowing the Knowledge Gaps on the Duration of Transferred Protective Immunity and on Vaccination Frequency

2020-03-21T20:08:07Z

Articulo Frontiers in Immunology; vol. 8 Maternal safety through pertussis vaccination and subsequent maternal–fetal-antibody transfer are well documented, but information on infant protection from pertussis by such antibodies and by subsequent vaccinations is scarce. Since mice are used extensively for maternal-vaccination studies, we adopted that model to narrow those gaps in our understanding of maternal pertussis immunization. Accordingly, we vaccinated female mice with commercial acellular pertussis (aP) vaccine and measured offspring protection against Bordetella pertussis challenge and specific-antibody levels with or without revaccination. Maternal immunization protected the offspring against pertussis, with that immune protection transferred to the offspring lasting for several weeks, as evidenced by a reduction (4–5 logs, p < 0.001) in the colony-forming-units recovered from the lungs of 16-week-old offspring. Moreover, maternal-vaccination-acquired immunity from the first pregnancy still conferred protection to offspring up to the fourth pregnancy. Under the conditions of our experimental protocol, protection to offspring from the aP-induced immunity is transferred both transplacentally and through breastfeeding. Adoptive-transfer experiments demonstrated that transferred antibodies were more responsible for the protection detected in offspring than transferred whole spleen cells. In contrast to reported findings, the protection transferred was not lost after the vaccination of infant mice with the same or other vaccine preparations, and conversely, the immunity transferred from mothers did not interfere with the protection conferred by infant vaccination with the same or different vaccines. These results indicated that aP-vaccine immunization of pregnant female mice conferred protective immunity that is transferred both transplacentally and via offspring breastfeeding without compromising the protection boostered by subsequent infant vaccination. These results—though admittedly not necessarily immediately extrapolatable to humans—nevertheless enabled us to test hypotheses under controlled conditions through detailed sampling and data collection. These findings will hopefully refine hypotheses that can then be validated in subsequent human studies.

De reactivo biológico al animal sintiente: el bienestar animal como cambio de paradigma en la investigación biomédica y su impacto en los resultados

2019-07-12T20:02:53Z

Revision From biological reagent to sentient animal: animal welfare as a paradigm shift in biomedical research and its impact on results Analecta Veterinaria; vol. 39, no. 1 El uso de animales como reactivos biológicos para investigación científica se ha justificado desde los inicios de la civilización, cuando solo servían para satisfacer las necesidades del hombre. El concepto de reactivo biológico ha cambiado al cobrar relevancia el bienestar animal, una problemática específica de la relación humanoanimal referida inicialmente a los animales de producción y que ha impactado en todos los usuarios de animales. Se logró avanzar en el conocimiento de las especies, sus necesidades y en la comprensión de su comportamiento. Con esta redefinición del animal surge un nuevo objeto de estudio para la ciencia: el estado del animal en sus intentos de lidiar con su entorno y de afrontar las demandas del ambiente. Como consecuencia, se han realizado enriquecimientos del ambiente sin suficientes estudios previos llevando a la obtención de resultados erróneos. Por lo tanto, es imperativo trabajar con indicadores específicos de bienestar que permitan diagnosticar y remediar las condiciones de pobre bienestar. Los animales provistos a los investigadores deberían contar con certificaciones sobre la cepa, condiciones de crianza y, además, tipo y modalidad de enriquecimiento e indicadores de bienestar animal antes de iniciar su utilización. En el futuro, el bienestar animal no solo debe estar en la nota ética, sino que debe ser parte inexcusable de la sección metodológica de los estudios experimentales.; The use of animals for scientific research has been justified since the beginnings of civilization, when they were considered as a biological reagent and only served to meet the needs of humans. This concept changed when ethical considerations towards their use as experimental beings began to have greater relevance. The birth of animal welfare has impacted the entire scientific community and all animal users, allowing a greater understanding of the needs and behavior of different species. From this redefinition of the animal as a biological reagent a new object of study arises: the relationship of the animal with its environment and its attempts to cope with the demands of the environment. Several attempts have been made to enrich the environment of experimental animals in order to improve their welfare but often in a poorly studied manner, and this has produced erroneous scientific results. Therefore, it is imperative to work with specific indicators of wellbeing that diagnose and remedy poor welfare conditions, and accurately communicate the conditions of the groups from which the statements are made. Thus, animals provided to researchers should be accompanied with certifications about strain, breeding conditions, type of enrichment and animal welfare indicators, prior to their use. In the future, animal welfare should not only be on the ethical note of experimental studies, but also be an indisputable part in the methodological section.

Modificación de la respuesta de ratones macho con trasplante tumoral subcutáneo a la orina de hembras en celo

2020-11-15T04:06:41Z

Objeto de conferencia I Reunión de Biología del Comportamiento del Cono Sur - Comporta 2017 - VI JUCA (Facultad de Ciencias Exatas y Naturales, UBA, 2 al 4 de agosto de 2017) La variabilidad comportamental y los comportamientos “de lujo” sugieren que las necesidades básicas de los animales se encuentran satisfechas y, por lo tanto, sirven como indicadores de bienestar animal. La eficiencia reproductiva es un indicador clásico, en el que su disminución demuestra que dichas necesidades se encuentran insatisfechas. Sin embargo, falla en demostrar alteraciones leves en la homeostasis del individuo con el medio ambiente. En este sentido, la motivación para iniciar un comportamiento que no es esencial podría ser un indicador más sensible de una reducción del bienestar. En el presente trabajo evaluamos el interés de ratones macho nude (stock N:NIH(S)- Fox1nu) con un trasplante tumoral subcutáneo por la orina de hembras en celo, en un paradigma denominado “Female urine seeking test (FUST)”.

El efecto del enriquecimiento ambiental sobre la variabilidad de parámetros fisiológicos y conductuales en ratones de laboratorio

2020-11-02T04:07:06Z

Tesis de doctorado Carbone, Cecilia; Ferrari, Héctor Ricardo Doctor en Ciencias Veterinarias; Universidad Nacional de La Plata El enriquecimiento ambiental constituye una forma de mejorar el bienestar de los animales de experimentación. En muchos países, el enriquecimiento del ambiente en los bioterios es una exigencia respaldada por una legislación; en Argentina esta temática está parcialmente desarrollada. El bienestar brinda a los animales en cautiverio la posibilidad de expresar la mayor parte de su comportamiento específico preservando su salud y permitiendo obtener resultados confiables cuando se los utiliza como modelos. Hay mucha bibliografía al respecto en favor del enriquecimiento en animales de experimentación,en zoológicos y granjas, pero muchos autores argumentan que enriquecer el ambiente de los animales bajo experiencia, altera las condiciones estandarizadas de alojamiento y aumenta las variables; y en consecuencia modifica los resultados de las investigaciones. En contraposición, otros autores consideran que un animal criado en un ambiente enriquecido se ve favorecido para desarrollar todas sus características comportamentales y también para no alterarse ante cambios inesperados; dando respuestas más uniformes, disminuyendo las variables experimentales y permitiendo utilizar menor número de animales. Hay pocos estudios en ratones que consideran este tema, por lo tanto el objetivo de este estudio es analizar las varianzas de los parámetros fisiológicos y del comportamiento en esta especie criados con y sin enriquecimiento ambiental respectivamente.