Social cognition and emotional rehabilitation in participants with schizofrenia.

Introduction: People with schizophrenia have deficits in social cognition, emotion and social perception, as well as attributional style. The purpose of this study was to evaluate the efficacy of a multicomponent social cognition training program, e-Motional Training® (ET), in people with schizophrenia and to compare its efficacy with people who did not receive it. Therefore, a single-blind RCT was conducted in participants with a diagnosis of schizophrenia. Methods: A randomized, single-blind, clinical trial was conducted with 50 stable outparticipants with schizophrenia (registry number CHUC_2019_109). All participants (control and intervention) were treated with pharmacotherapy, case management and were on Individual Placement and Support methodology for competitive employment. The intervention group was treated with ET, an online program designed for social cognition rehabilitation. Pre and post assessment was performed using different battery of tests. General mixed models with subject identification and repeated measures over time were used. Results: Different pre and post measurements were performed in the two groups. No significant differences were found in sociodemographic characteristics between the control and intervention groups. Improvements were obtained in the intervention group in the Ekman test (p = 0.009), mainly enhanced by the improvement shown in three emotions: fear, sadness and disgust (p = 0.041, p = 0.021 and p = 0.038 respectively). Conclusion: ET is a promising online training tool for social cognition deficits in schizophrenia, in particular, for the improvement of emotions.Clinical Trial Registration: https://beta.clinicaltrials.gov, NCT05866328.

Inhibition of Human Coronaviruses by Combinations of Host-Targeted and Direct-Acting Antivirals.

Antiviral compounds targeting cellular metabolism are part of the therapeutic arsenal to control the spread of virus infection, either as sole treatment or in combination with direct-acting antivirals (DAA) or vaccines. Here, we describe the effect of two of them, lauryl gallate (LG) and valproic acid (VPA) both exhibiting a wide antiviral spectrum, against infection by coronaviruses such as HCoV-229E, HCoV-OC43, and SARS-CoV-2. A consistent 2 to 4-log-decrease in virus yields was observed in the presence of each antiviral, with an average IC50 value of 1.6 µM for LG and 7.2 mM for VPA. Similar levels of inhibition were observed when adding the drug 1 h before adsorption, at the time of infection or 2 h after infection, supporting a postvirus entry mechanism of action. The specificity of the antiviral effect of LG against SARS-CoV-2, relative to other related compounds such as gallic acid (G) and epicatechin gallate (ECG), predicted to be better inhibitors according to in silico studies, was also demonstrated. The combined addition of LG, VPA, and remdesivir (RDV), a DAA with a proven effect against human coronaviruses, resulted in a robust synergistic effect between LG and VPA, and to a lesser extent between the other drug combinations. These findings reinforce the interest of these wide antiviral spectrum host-targeted compounds as a first line of defense against viral diseases or as a vaccine complement to minimize the gap in antibody-mediated protection evoked by vaccines, either in the case of SARS-CoV-2 or for other possible emerging viruses.

Parasitosis y antígenos TF, Tn y sTn / Parasitosis and TF, Tn and sTn antigens

Resumen Las investigaciones realizadas establecen una relación entre los epítopos T, Tn y sTn y las enfermedades parasitarias. Estos epítopos se expresan en un alto porcentaje de tumores epiteliales e inicialmente fueron relacionados con el síndrome T, caracterizado por trombocitopenia, leucopenia y anemia hemolítica. Se ha identificado la expresión de Tn en varios carcinomas, aunque los eventos asociados a su exposición en éstos parecen ser diferentes de los observados en el síndrome Tn. Diversos estudios comunicaron que estructuras asociadas a tumores, tales como los antígenos Tn y sialil-Tn, se expresan en algunos protozoarios y helmintos, y plantearon numerosos interrogantes a nivel de la interacción parásito-hospedador, de la glicobiología parasitaria y de las eventuales relaciones entre la biología de algunos parásitos y las células cancerígenas. Los hematíes son poliaglutinables cuando son aglutinados por casi todas las muestras de suero humano normal. Algunas formas de poliaglutinidad se deben a la exposición del determinante antigénico TF, mediante la eliminación del ácido N-acetilneuramínico, por la acción de neuraminidasas bacterianas o virales, aunque en los últimos años se ha comunicado el desenmascaramiento de este antígeno críptico eritrocitario por Ascaris lumbricoides y Trichinella spiralis. Debido a la importancia clínica de la activación T, se destaca la necesidad de estudiar la exposición del antígeno críptico TF en todos los parásitos cuyo hábitat sea la sangre, o bien en aquellos cuyos ciclos de vida comprendan una migración por el torrente circulatorio, pues su desenmascaramiento puede ocasionar autoaglutinación y/o hemólisis.

Abstract The investigations carried out establish a relationship between the T, Tn and sTn epitopes and the parasitic diseases. These epitopes are expressed in a high percentage of epithelial tumors, and they were initially related to the T syndrome, characterised by thrombocytopenia, leukopenia, and hemolytic anemia. The expression of Tn has been identified in several carcinomas, although the events associated with its exposure appears to be different from those observed in the Tn syndrome. Various studies report that tumor-associated structures such as Tn and sialyl-Tn antigens are expressed in some protozoa and helminths, raising numerous questions at the level of parasite-host interaction, parasitic glycobiology and eventual relationships between the biology of some parasites and cancer cells. Red cells are polyaglutinate when agglutinated by almost all normal human serum samples. Some forms of polyaglutinity are due to the exposure of the antigenic determinant TF, through the elimination of N-acetylneuraminic acid, by the action of bacterial or viral neuraminidases, although the unmasking of this erythrocyte cryptic antigen by Ascaris lumbricoides and Trichinella spiralis has been reported in recent years. Due to the clinical importance of T activation, the need to study the exposure of the cryptic TF antigen in all parasites whose habitats are blood or whose life cycles include migration through the circulatory stream is highlighted, since its unmasking can cause autoagglutination and/or hemolysis.

Resumo As investigações realizadas estabelecem uma relação entre os epítopos T, Tn e sTn e doenças parasitárias. Esses epítopos são expressos em alta porcentagem de tumores epiteliais e foram inicialmente relacionados à síndrome T, caracterizada por trombocitopenia, leucopenia e anemia hemolítica. A expressão de Tn foi identificada em vários carcinomas, embora os eventos associados à sua exposição neles pareçam ser diferentes dos observados na síndrome Tn. Vários estudos relatam que estruturas associadas a tumores, tais como antígenos Tn e sialil-Tn, são expressos em alguns protozoários e helmintos, levantando inúmeras questões no nível da interação parasita-hospedeiro, glicobiologia parasitária e eventuais relações entre a biologia de alguns parasitas e células cancerígenas. Os glóbulos vermelhos são poliaglutináveis quando são aglutinados por quase todas as amostras de soro humano normal. Algumas formas de poliaglutinidade são devidas à exposição do determinante antigênico TF, pela eliminação do ácido N-acetilneuramínico, pela ação de neuraminidases bacterianas ou virais, embora nos últimos anos tenha sido relatado o desmascaramento desse antígeno eritrocitário críptico por Ascaris lumbricoides e Trichinella spiralis. Devido à importância clínica da ativação T, destaca-se a necessidade de estudar a exposição do antígeno críptico TF em todos os parasitas cujo habitat seja o sangue ou naqueles cujos ciclos de vida incluam migração pela corrente circulatória, uma vez que seu desmascaramento pode causar autoaglutinação e/ou hemólise.

Adaptive value of foot-and-mouth disease virus capsid substitutions with opposite effects on particle acid stability.

Foot-and-mouth disease virus (FMDV) is a picornavirus that exhibits an extremely acid sensitive capsid. This acid lability is directly related to its mechanism of uncoating triggered by acidification inside cellular endosomes. Using a collection of FMDV mutants we have systematically analyzed the relationship between acid stability and the requirement for acidic endosomes using ammonium chloride (NH4Cl), an inhibitor of endosome acidification. A FMDV mutant carrying two substitutions with opposite effects on acid-stability (VP3 A116V that reduces acid stability, and VP1 N17D that increases acid stability) displayed a rapid shift towards acid lability that resulted in increased resistance to NH4Cl as well as to concanamicyn A, a different lysosomotropic agent. This resistance could be explained by a higher ability of the mutant populations to produce NH4Cl-resistant variants, as supported by their tendency to accumulate mutations related to NH4Cl-resistance that was higher than that of the WT populations. Competition experiments also indicated that the combination of both amino acid substitutions promoted an increase of viral fitness that likely contributed to NH4Cl resistance. This study provides novel evidences supporting that the combination of mutations in a viral capsid can result in compensatory effects that lead to fitness gain, and facilitate space to an inhibitor of acid-dependent uncoating. Thus, although drug-resistant variants usually exhibit a reduction in viral fitness, our results indicate that compensatory mutations that restore this reduction in fitness can promote emergence of resistance mutants.

Immunogenicity of Foot-and-Mouth Disease Virus Dendrimer Peptides: Need for a T-Cell Epitope and Ability to Elicit Heterotypic Responses.

An approach based on a dendrimer display of B- and T-cell epitopes relevant for antibody induction has been shown to be effective as a foot-and-mouth disease (FMD) vaccine. B2T dendrimers combining two copies of the major FMD virus (FMDV) type O B-cell epitope (capsid proteinVP1 (140-158)) covalently linked to a heterotypic T-cell epitope from non-structural protein 3A (21-35), henceforth B2T-3A, has previously been shown to elicit high neutralizing antibody (nAb) titers and IFN-γ-producing cells in both mice and pigs. Here, we provide evidence that the B- and T-cell epitopes need to be tethered to a single molecular platform for successful T-cell help, leading to efficient nAb induction in mice. In addition, mice immunized with a non-covalent mixture of B2T-3A dendrimers containing the B-cell epitopes of FMDV types O and C induced similarly high nAb levels against both serotypes, opening the way for a multivalent vaccine platform against a variety of serologically different FMDVs. These findings are relevant for the design of vaccine strategies based on B- and T-cell epitope combinations.

Peptide-Based Vaccines: Foot-and-Mouth Disease Virus, a Paradigm in Animal Health.

Vaccines are considered one of the greatest global health achievements, improving the welfare of society by saving lives and substantially reducing the burden of infectious diseases. However, few vaccines are fully effective, for reasons ranging from intrinsic limitations to more contingent shortcomings related, e.g., to cold chain transport, handling and storage. In this context, subunit vaccines where the essential antigenic traits (but not the entire pathogen) are presented in rationally designed fashion have emerged as an attractive alternative to conventional ones. In particular, this includes the option of fully synthetic peptide vaccines able to mimic well-defined B- and T-cell epitopes from the infectious agent and to induce protection against it. Although, in general, linear peptides have been associated to low immunogenicity and partial protection, there are several strategies to address such issues. In this review, we report the progress towards the development of peptide-based vaccines against foot-and-mouth disease (FMD) a highly transmissible, economically devastating animal disease. Starting from preliminary experiments using single linear B-cell epitopes, recent research has led to more complex and successful second-generation vaccines featuring peptide dendrimers containing multiple copies of B- and T-cell epitopes against FMD virus or classical swine fever virus (CSFV). The usefulness of this strategy to prevent other animal and human diseases is discussed.

Surgeon-led 7-VINCut Antibiotic Stewardship Intervention Decreases Duration of Treatment and Carbapenem Use in a General Surgery Service.

Antibiotic stewardship programs optimize the use of antimicrobials to prevent the development of resistance and improve patient outcomes. In this prospective interventional study, a multidisciplinary team led by surgeons implemented a program aimed at shortening the duration of antibiotic treatment <7 days. The impact of the intervention on antibiotic consumption adjusted to bed-days and discharges, and the isolation of multiresistant bacteria (MRB) was also studied. Furthermore, the surgeons were surveyed regarding their beliefs and feelings about the program. Out of 1409 patients, 40.7% received antibiotic therapy. Treatment continued for over 7 days in 21.5% of cases, and, as can be expected, source control was achieved in only 48.8% of these cases. The recommendations were followed in 90.2% of cases, the most frequent being to withdraw the treatment (55.6%). During the first 16 months of the intervention, a sharp decrease in the percentage of extended treatments, with R2 = 0.111 was observed. The program was very well accepted by surgeons, and achieved a decrease in both the consumption of carbapenems and in the number of MRB isolations. Multidisciplinary stewardship teams led by surgeons seem to be well received and able to better manage antibiotic prescription in surgery.

Association of Porcine Swine Leukocyte Antigen (SLA) Haplotypes with B- and T-Cell Immune Response to Foot-and-Mouth Disease Virus (FMDV) Peptides.

Dendrimer peptides are promising vaccine candidates against the foot-and-mouth disease virus (FMDV). Several B-cell epitope (B2T) dendrimers, harboring a major FMDV antigenic B-cell site in VP1 protein, are covalently linked to heterotypic T-cell epitopes from 3A and/or 3D proteins, and elicited consistent levels of neutralizing antibodies and IFN-γ-producing cells in pigs. To address the contribution of the highly polymorphic nature of the porcine MHC (SLA, swine leukocyte antigen) on the immunogenicity of B2T dendrimers, low-resolution (Lr) haplotyping was performed. We looked for possible correlations between particular Lr haplotypes with neutralizing antibody and T-cell responses induced by B2T peptides. In this study, 63 pigs immunized with B2T dendrimers and 10 non-immunized (control) animals are analyzed. The results reveal a robust significant correlation between SLA class-II Lr haplotypes and the T-cell response. Similar correlations of T-cell response with SLA class-I Lr haplotypes, and between B-cell antibody response and SLA class-I and SLA class-II Lr haplotypes, were only found when the sample was reduced to animals with Lr haplotypes represented more than once. These results support the contribution of SLA class-II restricted T-cells to the magnitude of the T-cell response and to the antibody response evoked by the B2T dendrimers, being of potential value for peptide vaccine design against FMDV.

Immunogenicity of a Dendrimer B2T Peptide Harboring a T-Cell Epitope From FMDV Non-structural Protein 3D.

Synthetic dendrimer peptides are a promising strategy to develop new FMD vaccines. A dendrimer peptide, termed B2T-3A, which harbors two copies of the major FMDV antigenic B-cell site [VP1 (140-158)], covalently linked to a heterotypic T-cell from the non-structural protein 3A [3A (21-35)], has been shown to protect pigs against viral challenge. Interestingly, the modular design of this dendrimer peptide allows modifications aimed at improving its immunogenicity, such as the replacement of the T-cell epitope moiety. Here, we report that a dendrimer peptide, B2T-3D, harboring a T-cell epitope from FMDV 3D protein [3D (56-70)], when inoculated in pigs, elicited consistent levels of neutralizing antibodies and high frequencies of IFN-γ-producing cells upon in vitro recall with the homologous dendrimers, both responses being similar to those evoked by B2T-3A. Lymphocytes from B2T-3A-immunized pigs were in vitro-stimulated by T-3A peptide and to a lesser extent by B-peptide, while those from B2T-3D- immunized animals preferentially recognized the T-3D peptide, suggesting that this epitope is a potent inducer of IFN-γ producing-cells. These results extend the repertoire of T-cell epitopes efficiently recognized by swine lymphocytes and open the possibility of using T-3D to enhance the immunogenicity and the protection conferred by B2T-dendrimers.

Designing Functionally Versatile, Highly Immunogenic Peptide-Based Multiepitopic Vaccines against Foot-and-Mouth Disease Virus.

A broadly protective and biosafe vaccine against foot-and-mouth disease virus (FMDV) remains an unmet need in the animal health sector. We have previously reported solid protection against serotype O FMDV afforded by dendrimeric peptide structures harboring virus-specific B- and T-cell epitopes, and also shown such type of multivalent presentations to be advantageous over simple B-T-epitope linear juxtaposition. Chemically, our vaccine platforms are modular constructions readily made from specified B- and T-cell epitope precursor peptides that are conjugated in solution. With the aim of developing an improved version of our formulations to be used for on-demand vaccine applications, we evaluate in this study a novel design for epitope presentation to the immune system based on a multiple antigen peptide (MAP) containing six immunologically relevant motifs arranged in dendrimeric fashion (named B2T-TB2). Interestingly, two B2T units fused tail-to-tail into a single homodimer platform elicited higher B- and T-cell specific responses than former candidates, with immunization scores remaining stable even after 4 months. Moreover, this macromolecular assembly shows consistent immune response in swine, the natural FMDV host, at reduced dose. Thus, our versatile, immunogenic prototype can find application in the development of peptide-based vaccine candidates for various therapeutic uses using safer and more efficacious vaccination regimens.

Trichinella spiralis y Trichinella patagoniensis: estudio de la carga globular aplicando el método de Azul Alcian / Trichinella spiralis and Trichinella patagoniensis: study of globular charge applying Alcian Blue method / Trichinella spiralis e Trichinella patagoniensis: estudo da carga globular pelo método de Azul de Alcian

Resumen Los residuos de ácido siálico de las glicoproteínas de superficie son los principales responsables de la carga negativa eritrocitaria. El objetivo de este trabajo fue estudiar alteraciones de carga globular producidas por Trichinella spiralis y Trichinella patagoniensis. Se trabajó con concentrados de larvas musculares de ambas especies y con eritrocitos frescos. Se incubó el sedimento globular con igual volumen de concentrado larval (1 y 2 horas). Los controles fueron incubados con solución salina. Se aplicó el método de Azul Alcian y se determinó el coeficiente experimental de carga aniónica eritrocitaria (CexpCAE). Los resultados mostraron que la carga disminuyó con el aumento del tiempo de tratamiento para ambas especies. Los valores de CexpCAE de las suspensiones incubadas con T. spiralis fueron menores que con T. patagoniensis, indicando que T. spiralis produjo mayor disminución de carga que T. patagoniensis. Se concluye que la desialización producida por ambas especies no es la misma, lo que sugiere que la relación hospedador-parásito que se establecería in vivo sería distinta.

Abstract The sialic acid residues of the surface glycoproteins are mainly responsible for the erythrocyte negative charge. The objective of this work was to study alterations of globular charge produced by Trichinella spiralis and Trichinella patagoniensis. Work was carried out on muscle larvae concentrates of both species and fresh erythrocytes. The treatment was performed by incubating the globular pellet with equal volume of larval concentrate (1 and 2 hours). Controls were incubated with saline solution. The Alcian Blue method was applied and the experimental coefficient of erythrocyte anion charge (expCEAC) was determined. The results showed that the globular charge decreased with increasing treatment time for both species. The expCEAC values of the suspensions incubated with T. spiralis were lower than with T. patagoniensis, indicating that T. spiralis produced a greater decrease in charge than T. patagoniensis. It is concluded that the desialization produced by both species is not the same, suggesting that the host-parasite relationship that would be established in vivo would be different.

Resumo Os resíduos de ácido siálico das glicoproteínas de superfície são os principais responsáveis pela carga negativa dos eritrócitos. O objetivo desse trabalho foi estudar as alterações da carga globular produzidas por Trichinella spiralis e Trichinella patagoniensis. Trabalhamos com concentrados de larvas musculares de ambas as espécies e com eritrócitos frescos. O tratamento foi realizado incubando o sedimento globular com igual volume de concentrado larval (1 e 2 horas), Os controles foram incubados com solução salina. Foi aplicado o método de Azul de Alcian e se determinou o coeficiente experimental de carga aniônica de eritrócitos (CexpCAE). Os resultados mostraram que a carga diminuiu com o aumento do tempo de tratamento para ambas as espécies. Os valores de CexpCAE das suspensões incubadas com T. spiralis foram menores que com T. patagoniensis, indicando que T. spiralis produziu uma diminuição maior na carga que T. patagoniensis. Conclui-se que a dessalinização produzida por ambas as espécies não é a mesma, sugerindo que a relação hospedeiro parasita que seria estabelecida in vivo é diferente.

Trichinella spiralis y Trichinella patagoniensis: cinética de desialización eritrocitaria / Trichinella spiralis and Trichinella patagoniensis: kinetics of erythrocyte desialization / Trichinella spiralis e Trichinella patagoniensis: cinética de dessialização eritrocitária

El objetivo del trabajo fue estudiar la cinética de desialización eritrocitaria producida por larvas infectantes de Trichinella spiralis y Trichinella patagoniensis. Se trabajó con 7 suspensiones eritrocitarias incubadas con 1.000±200 larvas musculares/mL, durante 2 horas, tomando muestra al tiempo inicial y cada 15 minutos. Los respectivos eritrocitos controles se incubaron de la misma manera con solución salina. Se aplicaron el método de titulación por Polibrene calculando el CexpST y un análisis de varianza (ANOVA) con las comparaciones múltiples según Tukey. Los resultados mostraron que el valor promedio de CexpST disminuyó con el aumento del tiempo de incubación, para ambas especies. En el tratamiento con T. spiralis no hubo diferencias significativas entre el valor medio del coeficiente a tiempo 60 y 75 minutos, mientras que con T. patagoniensis, a 45 y 60 minutos. Todas las restantes diferencias fueron significativas. La comparación entre los tratamientos, para cada uno de los tiempos, mostró que al tiempo inicial el coeficiente promedio no difirió entre las especies, pero que a todos los otros tiempos fue significativamente menor en la incubación de los eritrocitos con T. spiralis. Se concluye que la relación hospedador-parásito que se establece en ambos casos es distinta y probablemente también la capacidad de adaptación y de daño al hombre.

The objective of this work was to study the kinetics of erythrocyte desialization produced by infective larvae of Trichinella spiralis and Trichinella patagoniensis. It was performed on 7 erythrocyte suspensions incubated with 1,000±200 muscle larvae/ mL for 120 minutes, taking samples at the initial time and every 15 minutes. The respective control erythrocytes were incubated in the same way with saline solution. The Polybrene Titration method calculating the CexpST and variance analysis (ANOVA) with the multiple comparisons according to Tukey were applied. The results showed that the average value of CexpST decreased with the increase in incubation time, for both species. There were no significant differences between the mean value of the coefficient at 60 and 75 minutes in the treatment with T. spiralis, while neither were there any differences between 45 and 60 minutes in the incubation with T. patagoniensis. All other differences were significant. The comparison between the two treatments, for each of the times, showed that at the initial time the average coefficient did not differ between the species, but at all other times it was significantly lower in the incubation of the erythrocytes with T. spiralis. It is concluded that the parasite host relationship that is established in both cases is different and probably also is the ability to adapt and cause harm to man.

O objetivo do trabalho foi estudar a cinética de dessialização eritrocitária. produzida por larvas infectantes de Trichinella spiralis e Trichinella patagoniensis. O trabalho foi feito com 7 suspensões eritrocitárias incubadas com 1.000±200 larvas musculares/mL por 2 horas, colhendo amostras no tempo inicial e a cada 15 minutos. Os respectivos eritrócitos-controle foram incubados da mesma forma com solução salina. Foi aplicado o método de titulação por Polibreno calculando o CexpST e também uma análise da variância (ANOVA) com as comparações múltiplas de acordo com Tukey. Os resultados mostraram que o valor médio de CexpST diminuiu com o aumento do tempo de incubação para ambas as espécies. No tratamento com T. spiralis não houve diferenças significativas entre o valor médio do coeficiente no tempo 60 e 75 minutos, ao passo que com T. patagoniensis, aos 45 e 60 minutos. Todas as diferenças restantes foram significativas. A comparação entre os tratamentos, para cada um dos tempos, mostrou que no tempo inicial o coeficiente médio não diferiu entre as espécies, mas que em todos os outros tempos foi significativamente menor na incubação dos eritrócitos com T. spiralis. A conclusão é que a relação hospedeiro-parasita, estabelecida em ambos os casos, é diferente e provavelmente também a capacidade de adaptação e dano ao homem.

A bivalent B-cell epitope dendrimer peptide can confer long-lasting immunity in swine against foot-and-mouth disease.

Foot-and-mouth disease virus (FMDV) causes a widely extended contagious disease of livestock. We have previously reported that a synthetic dendrimeric peptide, termed B2 T(mal), consisting of two copies of a B-cell epitope [VP1(140-158)] linked through maleimide groups to a T-cell epitope [3A(21-35)] of FMDV, elicits potent B- and T-cell-specific responses and confers solid protection in pigs to type O FMDV challenge. Longer duration of the protective response and the possibility of inducing protection after a single dose are important requirements for an efficient FMD vaccine. Herein, we show that administration of two doses of B2 T(mal) elicited high levels of specific total IgGs and neutralizing antibodies that lasted 4-5 months after the peptide boost. Additionally, concomitant levels of IFN-γ-producing specific T cells were observed. Immunization with two doses of B2 T(mal) conferred a long-lasting reduced susceptibility to FMDV infection, up to 136 days (19/20 weeks) post-boost. Remarkably, a similar duration of the protective response was achieved by a single dose of B2 T(mal). The effect on the B2 T(mal) vaccine of RNA transcripts derived from non-coding regions in the FMDV genome, known to enhance the immune response and protection induced by a conventional inactivated vaccine, was also analysed. The contribution of our results to the development of FMD dendrimeric vaccines is discussed.

A Single Dose of Dendrimer B2T Peptide Vaccine Partially Protects Pigs against Foot-and-Mouth Disease Virus Infection.

Foot-and-mouth disease virus (FMDV) causes a highly contagious disease of cloven-hoofed animals whose control relies on efficient vaccination. We have reported that dendrimer peptide B2T, with two copies of FMDV B-cell epitope VP1 (136-154) linked through maleimide units to T-cell epitope 3A (21-35)], elicits potent B- and T-cell specific responses and confers solid protection in pigs to type-O FMDV challenge after two doses of peptide. Herein we now show that B2T evokes specific protective immune responses after administration of a single dose of either 2 or 0.5 mg of peptide. High titers of ELISA and neutralizing antibodies against FMDV were detectable at day 15 post-immunization. Likewise, activated T cells and induced IFN-γ response to in vitro recall with FMDV peptides were also detected by the same day. Further, in 70% of B2T-vaccinated pigs, full protection-no clinical signs of disease-was observed upon virus challenge at day 25 post-immunization. These results strengthen the potential of B2T as a safe, cost-effective candidate vaccine conferring adequate protection against FMDV with a single dose. The finding is particularly relevant to emergency scenarios permitting only a single shot immunization.

Swine T-Cells and Specific Antibodies Evoked by Peptide Dendrimers Displaying Different FMDV T-Cell Epitopes.

Dendrimeric peptide constructs based on a lysine core that comprises both B- and T-cell epitopes of foot-and-mouth disease virus (FMDV) have proven a successful strategy for the development of FMD vaccines. Specifically, B2T dendrimers displaying two copies of the major type O FMDV antigenic B-cell epitope located on the virus capsid [VP1 (140-158)], covalently linked to a heterotypic T-cell epitope from either non-structural protein 3A [3A (21-35)] or 3D [3D (56-70)], named B2T-3A and B2T-3D, respectively, elicit high levels of neutralizing antibodies (nAbs) and IFN-γ-producing cells in pigs. To assess whether the inclusion and orientation of T-3A and T-3D T-cell epitopes in a single molecule could modulate immunogenicity, dendrimers with T epitopes juxtaposed in both possible orientations, i.e., constructs B2TT-3A3D and B2TT-3D3A, were made and tested in pigs. Both dendrimers elicited high nAbs titers that broadly neutralized type O FMDVs, although B2TT-3D3A did not respond to boosting, and induced lower IgGs titers, in particular IgG2, than B2TT-3A3D. Pigs immunized with B2, a control dendrimer displaying two B-cell epitope copies and no T-cell epitope, gave no nABs, confirming T-3A and T-3D as T helper epitopes. The T-3D peptide was found to be an immunodominant, as it produced more IFN-γ expressing cells than T-3A in the in vitro recall assay. Besides, in pigs immunized with the different dendrimeric peptides, CD4+ T-cells were the major subset contributing to IFN-γ expression upon in vitro recall, and depletion of CD4+ cells from PBMCs abolished the production of this cytokine. Most CD4+IFN-γ+ cells showed a memory (CD4+2E3-) and a multifunctional phenotype, as they expressed both IFN-γ and TNF-α, suggesting that the peptides induced a potent Th1 pro-inflammatory response. Furthermore, not only the presence, but also the orientation of T-cell epitopes influenced the T-cell response, as B2TT-3D3A and B2 groups had fewer cells expressing both cytokines. These results help understand how B2T-type dendrimers triggers T-cell populations, highlighting their potential as next-generation FMD vaccines.

Inhibition of Porcine Viruses by Different Cell-Targeted Antiviral Drugs.

Antiviral compounds targeting cellular metabolism instead of virus components have become an interesting issue for preventing and controlling the spread of virus infection, either as sole treatment or as a complement of vaccination. Some of these compounds are involved in the control of lipid metabolism and/or membrane rearrangements. Here, we describe the effect of three of these cell-targeting antivirals: lauryl gallate (LG), valproic acid (VPA), and cerulenin (CRL) in the multiplication of viruses causing important porcine diseases. The results confirm the antiviral action in cultured cells of LG against African swine fever virus (ASFV), foot and mouth disease virus (FMDV), vesicular stomatitis virus (VSV), and swine vesicular disease virus (SVDV), as well as the inhibitory effect of VPA and CRL on ASFV infection. Other gallate esters have been also assayed for their inhibition of FMDV growth. The combined action of these antivirals has been also tested in ASFV infections, with some synergistic effects when LG and VPA were co-administered. Regarding the mode of action of the antivirals, experiments on the effect of the time of its addition in infected cell cultures indicated that the inhibition by VPA and CRL occurred at early times after ASFV infection, while LG inhibited a late step in FMDV infection. In all the cases, the presence of the antiviral reduced or abolished the induction of virus-specific proteins. Interestingly, LG also reduced mortality and FMDV load in a mouse model. The possible use of cell-targeted antivirals against porcine diseases is discussed.

Larvas recién nacidas de Trichinella spiralis: cinética de agregación eritrocitaria / Newborn larvae of Trichinella spiralis: erythrocyte aggregation kinetics

El objetivo de este trabajo fue estudiar la cinética de agregación eritrocitaria producida por dos concentraciones de larvas recién nacidas (LRN) de Trichinella spiralis. Se trabajó con 5 suspensiones eritrocitarias incubadas con 500 y 1.000±100 LRN/mL durante 120 minutos, con tomas de muestra al tiempo inicial y cada 15 minutos. Los respectivos controles se incubaron de la misma manera con solución salina. Se aplicaron el método de titulación por Polibrene calculando el CexpST y la técnica de análisis de la variancia con las comparaciones múltiples según Tukey. Los resultados mostraron para ambas concentraciones de LRN, que el coeficiente promedio disminuyó con el aumento del tiempo de incubación. En el tratamiento con 1.000 LRN/mL, el coeficiente promedio no presentó diferencias significativas a tiempo 0 y 15 minutos, ni entre 60 y 75 minutos, mientras que con 500 LRN/mL no hubo diferencias entre los tiempos 0, 15 y 30 minutos. Todas las restantes diferencias fueron significativas para ambas concentraciones larvales. El valor promedio de CexpST no difirió significativamente entre los dos tratamientos a tiempo 0 y 15 minutos, pero a todos los otros tiempos fue menor a mayor concentración de larvas. La experiencia realizada indicaría que in vivo, la cantidad de LRN y el tiempo que permanecen en circulación determinan el grado de desializacion eritrocitaria, y por lo tanto el riesgo de activación T y de alteraciones hemorreológicas en el hospedador.

The aim of this work was to study the kinetics of erythrocyte aggregation produced by two concentrations of Trichinella spiralis newborn larvae (NL). Work was performed with 5 erythrocyte suspensions incubated with 500 and 1000 ± 100 NL/mL for 120 minutes, taking samples at the initial time and every 15 minutes. The respective controls were incubated in the same way with saline solution. The Polybrene titration method calculating the CexpST and the variance analysis technique with the multiple comparisons according to Tukey were applied. The results showed that the average coefficient decreased with the rise in incubation time for both NL concentrations. The average coefficient did not present significant differences between the initial time and 15 minutes, nor between 60 and 75 minutes in the treatment with 1000 NL/mL, while there were no differences between 0,15 and 30 minutes in the treatment with 500 NL/mL. All other differences were significant for both larval concentrations. The average value of CexpST did not differ significantly between the two time treatments at zero time and 15 minutes, but at all other times it was less at a higher concentration of larvae. The experience carried out would indicate that in vivo, the amount of NL and the time that they remain in circulation determines the degree of erythrocyte desialylation, and therefore, the risk of T activation and hemorrheological alterations in the host.

O objetivo desse trabalho foi estudar a cinética de agregação eritrocitária produzida por duas concentrações de larvas recém nascidas (LRN) de Trichinella spiralis. O trabalho foi feito com 5 suspensões eritrocitárias incubadas com 500 e 1.000 ± 100 LRN/mL por 120 minutos, colhendo amostras no tempo inicial e a cada 15 minutos. Os respectivos controles foram incubados da mesma forma com solução salina. Foi aplicado o método de titulação por Polibreno e se calculou CexpST. e a técnica de análise da variância com as comparações múltiplas de acordo com Tukey. Os resultados mostraram, para ambas as concentrações de LRN, que o o coeficiente médio diminuiu com o aumento do tempo de incubação. No tratamento com 1.000 LRN/mL o coeficiente médio não mostrou diferenças significativas no tempo 0 e 15 minutos ou entre 60 e 75 minutos, ao passo que não houve diferenças com 500 LRN/mL entre tempos 0, 15 e 30 minutos. Todas as restantes diferenças foram significativas para ambas as concentrações de larvas. O valor médio de CexpST não diferiu significativamente entre os dois tratamentos no tempo de 0 e 15 minutos, mas em todos os outros tempos foi menor em maior concentração de larvas. A experiência realizada indicaria que in vivo a quantidade de LRN e o tempo que permanecem em circulação determina o grau de dessialização dos eritrócitos e, portanto, o risco de ativação T e de alterações hemorreológicas no hospedeiro.

Efecto de Trichinella spiralis y de Trichinella patagoniensis n.sp. sobre la desialización / Effect of Trichinella spiralis and Trichinella patagoniensis n.sp. on desialization

El ácido siálico tiene importantes funciones biológicas, muchas de las cuales determinan su participación en la respuesta inmune. El objetivo del trabajo fue comparar el efecto de Trichinella spiralis y Trichinella patagoniensis n.sp. sobre la desialización eritrocitaria. Se trabajó con 10 concentrados de larvas musculares de T. spiralis y 10 de T. patagoniensis de la misma concentración larval. Se realizó el tratamiento incubando el sedimento de eritrocitos frescos con igual volumen de concentrado larval (37 ºC), tomando muestra a los 30, 60 y 90 minutos. Los controles fueron incubados de la misma forma con solución salina. Se aplicó el método de Titulación de la Agregación por Polibrene y se determinó el CexpST. Los resultados mostraron que el valor medio del CexpST en los eritrocitos tratados con T. spiralis fue significativamente menor que en los glóbulos tratados con T. patagoniensis, para todos los tiempos estudiados. El aumento del tiempo de tratamiento también disminuyó significativamente el valor medio del CexpST para las dos especies. Éste fue significativamente menor a los 90 minutos de incubación que a los 60 minutos y éstos a su vez menores que a los 30 minutos. Se concluye que T. spiralis provocó mayor desialización eritrocitaria que T. patagoniensis en las condiciones experimentales estudiadas.

Sialic acid has important biological functions, many of which determine its participation in the immune response. The objective of this paper was to compare the effect of Trichinella spiralis and Trichinella patagoniensis n.sp. on erythrocyte desialization. Work was performed on 10 larval concentrates of muscle larvae of T. spiralis and 10 of T. patagoniensis of the same larval concentration. The treatment was carried out incubating the sediment of fresh erythrocytes with an equal volume of larval concentrate (37 °C), taking samples at 30, 60 and 90 minutes. The controls were incubated in the same way treated with saline solution. Titration of aggregation by Polybrene Method was applied and the CexpST was determined. The results showed that the mean value of CexpST in erythrocytes with T. spiralis was significantly lower than in the globules treated with T. patagoniensis, for all the studied times. The increase in treatment time also significantly decreased the mean value of CexpST for the two species, being significantly lower at 90 minutes of incubation than at 60 minutes and these in turn lower than at 30 minutes. It is concluded that T. spiralis caused greater erythrocyte desialization than T. patagoniensis in the experimental conditions studied.

O ácido siálico tem importantes funções biológicas, muitas das quais determinam sua participação na resposta imune. O objetivo foi comparar o efeito de Trichinella spiralis e Trichinella patagoniensis n.sp. sobre a dessialização eritrocitária. Trabalhou-se com 10 concentrados de larvas musculares de T. spiralis e 10 de T. patagoniensis da mesma concentração larval. Realizou-se o tratamento incubando o sedimento de eritrócitos frescos com igual volume de concentrado larval (37 ºC), tomando amostra aos 30, 60 e 90 minutos. Os controles foram incubados da mesma forma com solução salina. Foi aplicado o método de Titulação da Agregação por Polibrene e se determinouo CexpST. Os resultados mostraram que o valor médio do CexpST nos eritrócitos Tratados com T. spiralis foi significativamente menor que nos glóbulos tratados com T. patagoniensis, para todos os tempos estudados. O aumento do tempo de tratamento também diminuiu significativamente o valor médio do CexpST para as duas espécies, sendo significativamente menor aos 90 minutos de incubação que aos 60 minutos e eles por sua vez menores que aos 30 minutos. Conclui-se que T. spiralis provocou maior dessialização eritrocitária que T. patagoniensis nas condições experimentais estudadas.

Alteración del ácido siálico eritrocitario por efecto de Trichinella spiralis aplicando el método de Azul Alcian / Alteration of erythrocyte sialic acid by the effect of Trichinella spiralis applying the Alcian Blue method / Alteração do ácido siálico eritrocitário por efeito da Trichinella spiralis aplicando o método de Alcian Blue

Actualmente se reconoce que los ácidos siálicos están involucrados en múltiples funciones biológicas y que tienen un papel importante en la interacción parásito-hospedador. El objetivo del trabajo fue estudiar la alteración del ácido siálico eritrocitario por efecto de T. spiralis aplicando el método de Azul Alcian. Se trabajó con 11 concentrados de larvas musculares de T. spiralis (LM) y 9 de larvas recién nacidas de T. Spiralis (LRN) (total: 20) y con suspensiones de eritrocitos frescos. Se realizó el tratamiento incubando el sedimento globular con igual volumen de concentrado larval (37 ºC durante 1 hora). Los controles fueron incubados de la misma forma con solución salina. Se aplicó el método de Azul Alcian y se determinó CAE% en el control y en los glóbulos tratados. Se calculó CexpCAE. Los resultados mostraron que 5/9 de los concentrados de LRN y 9/11 de LM modificaron la carga globular. La media y la desviación estándar de los CexpCAE de las suspensiones en que la carga disminuyó por contacto con LRN y LM, fueron 0,614±0,1946 y 0,656±0,1865 respectivamente, mientras que en las que no se modificó resultó 0,955±0,0289 en el tratamiento con LRN y 0,93±0,0141 con LM. Se concluye que el Método de Azul Alcian es útil para estudiar las variaciones en la carga eritrocitaria por efecto de LRN y LM de T. spiralis.

It is now recognized that sialic acids are involved in multiple biological functions and that they have an important role in the parasite-host interaction. The objective of this work was to study the alteration of erythrocyte sialic acid by the effect of T. spiralis applying the Alcian Blue method. Work was carried out with 11 larval concentrates of ML and 9 of NL (total 20) and with fresh erythrocyte suspensions. The treatment was performed incubating the globular sediment with equal volume of larval concentrate (37 °C for 1 hour). The controls were incubated in the same way with saline solution. The Alcian Blue method was applied and CAE% was determined in the control and in the treated globules. CexpCAE was calculated. The results showed that 5/9 of the NL concentrates and 9/11 of ML modified the globular charge. The mean and standard deviation of the CexpCAE of the suspensions in which the charge decreased by contact with NL and ML were 0.614±0.1946 and 0.656±0.1865 respectively, whereas in those that did not change, it was 0.955±0.0289 in the NL treatment and 0.93±0.0141 in the ML. It is concluded that the Alcian Blue Method is useful to study the variations in erythrocyte charge due to NL and ML of T. spiralis.

Atualmente se reconhece que os ácidos siálicos estão envolvidos em múltiplas funções biológicas e que têm um papel importante na interação parasita-hospedeiro. O objetivo do trabalho foi estudar a alteração do ácido siálico eritrocitário por efeito de T. spiralis aplicando o método do Alcian Blue. Trabalhou-se com 11 concentrados de larvas musculares de T. spiralis (LM) e 9 de larvas recém-nascidas de T. Spiralis (LRN) (total: 20) e com suspensões de eritrócitos frescos. Realizou-se o tratamento incubando o sedimento globular com igual volume de concentrado larval (37 ºC durante 1 hora). Os controles foram incubados da mesma forma com solução salina. Aplicou-se o método de Azul Alcian e determinou-se CAE% no controle e nos glóbulos tratados. Calculou-se CexpCAE. Os resultados mostraram que 5/9 dos concentrados de LRN e 9/11 de LM modificaram o carga globular. A média e o desvio padrão dos CexpCAE das suspensões em que a carga diminuiu por contato com LRN e LM, foram 0,614±0,1946 e 0,656±0,1865 respectivamente, enquanto que naquelas onde não se modificou, resultou 0,955±0,0289 no tratamento com LRN e 0,93±0,0141 com LM. Conclui-se que o método de Alcian Blue é útil para estudar as variações na carga eritrocitária por LRN e LM de T. spiralis.