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1.
Environ Microbiol Rep ; 16(3): e13265, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38747207

RESUMEN

Role of dust in Salmonella transmission on chicken farms is not well characterised. Salmonella Typhimurium (ST) infection of commercial layer chickens was investigated using a novel sprinkling method of chicken dust spiked with ST and the uptake compared to a conventional oral infection. While both inoculation methods resulted in colonisation of the intestines, the Salmonella load in liver samples was significantly higher at 7 dpi after exposing chicks to sprinkled dust compared to the oral infection group. Infection of chickens using the sprinkling method at a range of doses showed a threshold for colonisation of the gut and organs as low as 1000 CFU/g of dust. Caecal content microbiota analysis post-challenge showed that the profiles of chickens infected by the sprinkling and oral routes were not significantly different; however, both challenges induced differences when compared to the uninfected negative controls. Overall, the study showed that dust sprinkling was an effective way to experimentally colonise chickens with Salmonella and alter the gut microbiota than oral gavage at levels as low as 1000 CFU/g dust. This infection model mimics the field scenario of Salmonella infection in poultry sheds. The model can be used for future challenge studies for effective Salmonella control.


Asunto(s)
Pollos , Polvo , Microbioma Gastrointestinal , Enfermedades de las Aves de Corral , Salmonelosis Animal , Salmonella typhimurium , Animales , Pollos/microbiología , Salmonella typhimurium/crecimiento & desarrollo , Polvo/análisis , Salmonelosis Animal/microbiología , Salmonelosis Animal/prevención & control , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/prevención & control , Ciego/microbiología , Hígado/microbiología
2.
Front Vet Sci ; 11: 1364731, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38686027

RESUMEN

Among the Salmonella reduction strategies in poultry production, one option is to use a Salmonella vaccine. The aim of vaccinating layer flocks is to reduce the shedding of wild-type Salmonella in the poultry environment, thereby reducing the contamination of poultry products (eggs and meat). Nutritive diluent and a higher dose of vaccine may enhance its colonization potential in the gut of chickens. In this study, a commercially available live attenuated vaccine (Vaxsafe® ST) was reconstituted in different media and delivered orally to day-old chicks at three different doses (107, 108, and 109 CFU/chick). Gut colonization of the vaccine strain and the effects of vaccination on gut microbiota were assessed in commercial-layer chickens. The vaccine diluent and dosage minimally affected microbiota alpha diversity. Microbiota beta diversity was significantly different (P < 0.05) based on the vaccine diluent and dose, which indicated that the vaccinated and unvaccinated chickens had different gut microbial communities. Differences were noted in the abundance of several genera, including Blautia, Colidextribacter, Dickeya, Enterococcus, Lactobacillus, Pediococcus, and Sellimonas. The abundance of Colidextribacter was significantly lower in chickens that received vaccine reconstituted in Marek's and water diluents, while Lactobacillus abundance was significantly lower in the water group. The highest vaccine dose (109 CFU/chick) did not significantly alter (P > 0.05) the abundance of microbial genera. Chicken age affected the microbiota composition more significantly than the vaccine dose and diluent. The abundance of Lactobacillus, Blautia, Caproiciproducens, Pediococcus, and Colidextribacter was significantly higher on day 14 compared with day 7 post-vaccination. The Salmonella Typhimurium vaccine load in the caeca was not significantly affected by diluent and vaccine dose; however, it was significantly lower (P < 0.0001) on day 14 compared with day 7 post-vaccination. Overall, the S. Typhimurium vaccine minimally affected the gut microbiota structure of layer chicks, whereas changes in microbiota were more significant with chicken age.

4.
J Virol ; 97(8): e0060423, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37555661

RESUMEN

Viruses have evolved diverse strategies to evade the host innate immune response and promote infection. The retinoic acid-inducible gene I (RIG-I)-like receptors RIG-I and MDA5 are antiviral factors that sense viral RNA and trigger downstream signal via mitochondrial antiviral-signaling protein (MAVS) to activate type I interferon expression. 14-3-3ε is a key component of the RIG-I translocon complex that interacts with MAVS at the mitochondrial membrane; however, the exact role of 14-3-3ε in this pathway is not well understood. In this study, we demonstrate that 14-3-3ε is a direct substrate of both the poliovirus and coxsackievirus B3 (CVB3) 3C proteases (3Cpro) and that it is cleaved at Q236↓G237, resulting in the generation of N- and C-terminal fragments of 27.0 and 2.1 kDa, respectively. While the exogenous expression of wild-type 14-3-3ε enhances IFNB mRNA production during poly(I:C) stimulation, expression of the truncated N-terminal fragment does not. The N-terminal 14-3-3ε fragment does not interact with RIG-I in co-immunoprecipitation assays, nor can it facilitate RIG-I translocation to the mitochondria. Probing the intrinsically disordered C-terminal region identifies key residues responsible for the interaction between 14-3-3ε and RIG-I. Finally, overexpression of the N-terminal fragment promotes CVB3 infection in mammalian cells. The strategic enterovirus 3Cpro-mediated cleavage of 14-3-3ε antagonizes RIG-I signaling by disrupting critical interactions within the RIG-I translocon complex, thus contributing to evasion of the host antiviral response. IMPORTANCE Host antiviral factors work to sense virus infection through various mechanisms, including a complex signaling pathway known as the retinoic acid-inducible gene I (RIG-I)-like receptor pathway. This pathway drives the production of antiviral molecules known as interferons, which are necessary to establish an antiviral state in the cellular environment. Key to this antiviral signaling pathway is the small chaperone protein 14-3-3ε, which facilitates the delivery of a viral sensor protein, RIG-I, to the mitochondria. In this study, we show that the enteroviral 3C protease cleaves 14-3-3ε during infection, rendering it incapable of facilitating this antiviral response. We also find that the resulting N-terminal cleavage fragment dampens RIG-I signaling and promotes virus infection. Our findings reveal a novel viral strategy that restricts the antiviral host response and provides insights into the mechanisms underlying 14-3-3ε function in RIG-I antiviral signaling.


Asunto(s)
Infecciones por Picornaviridae , Picornaviridae , Animales , Cisteína Endopeptidasas/metabolismo , Proteína 58 DEAD Box/metabolismo , Inmunidad Innata , Mamíferos , Péptido Hidrolasas/metabolismo , Picornaviridae/metabolismo , Transducción de Señal , Tretinoina , Proteínas Virales/metabolismo , Infecciones por Picornaviridae/inmunología , Infecciones por Picornaviridae/virología , Proteasas Virales 3C
5.
Vaccine ; 41(21): 3358-3366, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37100722

RESUMEN

The live attenuated temperature sensitive vaccine strain MS-H (Vaxsafe® MS, Bioproperties Pty. Ltd., Australia) is widely used to control disease associated with M. synoviae infection in commercial poultry. MS-H was derived from a field strain (86079/7NS) through N-methyl-N'-nitro-N-nitrosoguanidine (NTG)-induced mutagenesis. Whole genomic sequence analysis of the MS-H and comparison with that of the 86079/7NS have found that MS-H contains 32 single nucleotide polymorphisms (SNPs). Three of these SNPs, found in the obgE, oppF and gapdh genes, have been shown to be prone to reversion under field condition, albeit at a low frequency. Three MS-H reisolates containing the 86079/7NS genotype in obgE (AS2), obgE and oppF (AB1), and obgE, oppF and gapdh (TS4), appeared to be more immunogenic and transmissible compared to MS-H in chickens. To investigate the influence of these reversions in the in vitro fitness of M. synoviae, the growth kinetics and steady state metabolite profiles of the MS-H reisolates, AS2, AB1 and TS4, were compared to those of the vaccine strain. Steady state metabolite profiling of the reisolates showed that changes in ObgE did not significantly influence the metabolism, while changes in OppF was associated with significant alterations in uptake of peptides and/or amino acids into the M. synoviae cell. It was also found that GAPDH plays a role in metabolism of the glycerophospholipids as well as an arginine deiminase (ADI) pathway. This study underscores the role of ObgE, OppF and GAPDH in M. synoviae metabolism, and suggests that the impaired fitness arising from variations in ObgE, OppF and GAPDH contributes to attenuation of MS-H.


Asunto(s)
Infecciones por Mycoplasma , Mycoplasma synoviae , Enfermedades de las Aves de Corral , Animales , Infecciones por Mycoplasma/veterinaria , Mycoplasma synoviae/genética , Pollos , Mutación , Mutagénesis , Vacunas Atenuadas/genética , Enfermedades de las Aves de Corral/prevención & control
6.
Vet Microbiol ; 280: 109721, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36948084

RESUMEN

Poultry vaccines are often administered using water as a suspension media and applied using an oral or coarse spray method. Gel-based vaccine diluents have been developed as an alternative vaccine delivery method. Gels are more viscous, and droplets adhere more effectively to feathers giving the vaccine a longer time to be ingested (through preening). Application of gel diluents with live bacterial vaccines, however, is limited. The present study tested a gel diluent prepared in various media, using a live, attenuated Salmonella Typhimurium vaccine, Vaxsafe ST. Reconstitution in gel diluent did not negatively affect vaccine viability or motility. The invasive capacity of vaccine suspended in gel diluent into cultured intestinal epithelial cells was also tested. Results demonstrated that vaccine suspended in gel diluent retained invasiveness. Day old chicks were orally administered with Vaxsafe ST suspended in gel diluent to characterize in vivo colonization capacity of the vaccine. The results revealed that the VaxSafe ST suspended in gel diluent could efficiently colonize the caeca of chicks, which is needed for the development of effective immunity.


Asunto(s)
Enfermedades de las Aves de Corral , Salmonelosis Animal , Vacunas contra la Salmonella , Animales , Salmonella typhimurium , Vacunas Atenuadas , Enfermedades de las Aves de Corral/microbiología , Pollos , Vacunas Bacterianas , Salmonelosis Animal/prevención & control , Vacunación/veterinaria , Vacunación/métodos
8.
Sci Rep ; 13(1): 227, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36604449

RESUMEN

Campylobacter hepaticus is an important pathogen which causes Spotty Liver Disease (SLD) in layer chickens. SLD results in an increase in mortality and a significant decrease in egg production and therefore is an important economic concern of the global poultry industry. The human pathogen Campylobacter jejuni encodes an N-linked glycosylation system that plays fundamental roles in host colonization and pathogenicity. While N-linked glycosylation has been extensively studied in C. jejuni and is now known to occur in a range of Campylobacter species, little is known about C. hepaticus glycosylation. In this study glycoproteomic analysis was used to confirm the functionality of the C. hepaticus N-glycosylation system. It was shown that C. hepaticus HV10T modifies > 35 proteins with an N-linked heptasaccharide glycan. C. hepaticus shares highly conserved glycoproteins with C. jejuni that are involved in host colonisation and also possesses unique glycoproteins which may contribute to its ability to survive in challenging host environments. C. hepaticus N-glycosylation may function as an important virulence factor, providing an opportunity to investigate and develop a better understanding the system's role in poultry infection.


Asunto(s)
Infecciones por Campylobacter , Campylobacter jejuni , Campylobacter , Hepatopatías , Enfermedades de las Aves de Corral , Animales , Humanos , Glicosilación , Infecciones por Campylobacter/veterinaria , Infecciones por Campylobacter/microbiología , Pollos/microbiología , Campylobacter/genética , Campylobacter/metabolismo , Hepatopatías/microbiología , Aves de Corral/metabolismo , Enfermedades de las Aves de Corral/microbiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
9.
Risk Anal ; 43(4): 820-837, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36114602

RESUMEN

Real-time tracking of tool and equipment inventories is a critical function of many organizations and sectors. For prisons and correctional facilities, tracking and monitoring of assets such as cookware, hardware, keys, janitorial equipment, vocational/technical specialty tools, etc., is essential for safety, security, trust, efficiency, education, etc. The performance of automated systems for this purpose can be diminished by a variety of emergent and future sociotechnical factors alone and in combination. This article introduces a methodology for contractor evaluation and selection in acquisition of innovative asset management systems, with an emphasis on evolving system requirements under uncertainty. The methodology features a scenario-based preferences analysis of emergent and future conditions that are disruptive to the performance of the asset-control system. The conditions are across technologies, operating environments, regulations, workforce behaviors, offender behaviors, prices and markets, organizations, cyber threats, etc. The methodology addresses the influence and interaction of the conditions to disrupt system priorities. Examples include: (i) infectious disease disrupting priorities among requirements and (ii)  radio-frequency identification (RFID) and wireless-technology innovations disrupting priorities among stakeholders. The combinations of conditions that most and least matter for the system acquisition are characterized. The methodology constitutes a risk register for monitoring sources of risk to project performance, schedule, and cost throughout the system lifecycle. The results will be of interest to both practitioners and scholars engaged in systems acquisition as the pandemic interacts with other factors to affect risk, uncertainty, and resilience of organizational missions and operations.


Asunto(s)
Pandemias , Dispositivo de Identificación por Radiofrecuencia , Gestión de Riesgos , Automatización , Instalaciones Correccionales
10.
Vet Microbiol ; 276: 109605, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36455495

RESUMEN

Prophylactic use of antimicrobials after administration of live vaccines is a common practice in the poultry industry, but the impact of this on the efficacy and duration of protection induced by the vaccines is unknown. The effect of treatment with tylosin on the efficacy of vaccination with the live attenuated M. gallisepticum strain, Vaxsafe MG ts-304, was examined. This vaccine has previously been shown to provide protection for at least 57 weeks. Ten-week-old specific-pathogen-free chickens were vaccinated with Vaxsafe MG ts-304 and then treated with tylosin at a therapeutic dose in drinking water from 6 weeks after vaccination. Tylosin was withdrawn 5 days before challenge with M. gallisepticum strain Ap3AS at 6, 10, 14, 18 or 22 weeks after vaccination. Air sac lesions, tracheal mucosal thickening and the concentrations of serum antibodies against M. gallisepticum were assessed at 2 weeks after challenge. The protection induced by the vaccine in the 6 weeks before initiation of tylosin treatment persisted for 18 weeks after vaccination, with lesions only observed in the air sacs of vaccinated birds that had been treated with tylosin after challenge at 22 weeks after vaccination. Concentrations of serum antibodies against M. gallisepticum began to decrease in vaccinated birds that had been treated with tylosin from 16 weeks after vaccination. This study has suggested that treatment of chickens with tylosin after vaccination with a live attenuated mycoplasma vaccine reduces the duration of protective immunity afforded by the vaccine.


Asunto(s)
Infecciones por Mycoplasma , Mycoplasma gallisepticum , Enfermedades de las Aves de Corral , Animales , Infecciones por Mycoplasma/prevención & control , Infecciones por Mycoplasma/veterinaria , Pollos , Tilosina/farmacología , Vacunas Bacterianas , Anticuerpos Antibacterianos , Enfermedades de las Aves de Corral/prevención & control , Vacunas Atenuadas
11.
J Int Bus Stud ; 54(3): 538-549, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35919376

RESUMEN

Managing multinational enterprise subsidiaries is a core facet of international business research. A shifting reality on the ground has triggered concerns around the waning relevance of the subsidiary because the MNE and its structure and processes have become increasingly complex. Consequently, more decentralized, responsive, and fluid organizational designs are now at the core of IB research. Juxtaposing recent arguments questioning subsidiary research altogether, we argue that IB scholars can explore and explain complex realities in the contemporary MNE without unnecessarily restricting the breadth of the field and giving up links to established research and theory. We reframe conversations around inward- and outward-looking perspectives, providing a path forward that emphasizes the importance of embracing the subsidiary concept in research reflecting today's complex business environment.


La gestion des filiales des entreprises multinationales (Multinational Enterprise - MNE) constitue une facette essentielle de la recherche en affaires internationales (International Business - IB). L'évolution de la réalité sur le terrain a suscité des inquiétudes quant à la perte de pertinence des filiales, étant donné que la MNE, sa structure et ses processus sont devenus de plus en plus complexes. Par conséquent, sont désormais au cœur de la recherche en IB les conceptions organisationnelles plus décentralisées, plus réactives et plus fluides. En juxtaposant les récents arguments remettant en cause la recherche portée sur les filiales, nous argumentons que les chercheurs en IB peuvent explorer et expliquer les réalités complexes des MNEs contemporaines sans restreindre inutilement l'étendue du domaine et sans renoncer aux liens avec la recherche et la théorie établies. Nous recadrons les conversations autour des perspectives autocentrées et orientées vers l'extérieur, tout en proposant une voie à suivre qui souligne l'importance d'inclure le concept de filiale dans la recherche reflétant l'environnement commercial complexe d'aujourd'hui.


La gestión de filiales de las empresas multinacionales (MNE por sus siglas en ingles) es una faceta central en la investigación en negocios internacionales. Una realidad cambiante en el terreno ha desencadenado preocupaciones sobre la disminución de la relevancia de la filial debido a que la empresa multinacional y su estructura y procesos se han vuelto cada vez más complejos. En consecuencia, los diseños organizacionales más descentralizados, receptivos y fluidos constituyen ahora el núcleo de la investigación sobre las empresas internacionales. Frente a los recientes argumentos que cuestionan la investigación sobre las filiales, sostenemos que los estudiosos de negocios internacionales pueden explorar y explicar las complejas realidades de las empresas multinacionales contemporáneas sin restringir innecesariamente la amplitud del campo ni renunciar a los vínculos con la investigación y la teoría establecidas. Replanteamos las conversaciones en torno a las perspectivas hacia adentro y hacia afuera, proporcionando un camino a seguir que subraya la importancia de adoptar el concepto de filial en la investigación que refleja el complejo entorno empresarial actual.


Gerenciar subsidiárias de empresas multinacionais (MNE) é uma faceta fundamental da pesquisa em negócios internacionais (IB). Uma realidade mutante no terreno desencadeou preocupações em torno da diminuição da relevância da subsidiária porque a MNE e sua estrutura e processos se tornaram cada vez mais complexos. Consequentemente, designs organizacionais mais descentralizados, responsivos e fluidos estão agora no cerne da pesquisa em IB. Justapondo argumentos recentes que questionam a pesquisa sobre subsidiárias como um todo, argumentamos que estudiosos de IB podem explorar e explicar realidades complexas na MNE contemporânea sem restringir desnecessariamente a amplitude do campo e abrir mão de relações com a pesquisas e a teoria estabelecidas. Reestruturamos conversas em torno de perspectivas que vislumbram o exterior e o interior, fornecendo um caminho a seguir que enfatiza a importância de adotar o conceito de subsidiária na pesquisa que reflita o complexo ambiente de negócios de hoje.

12.
Front Microbiol ; 13: 1042212, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36532420

RESUMEN

Infections caused by Mycoplasma synoviae are major welfare and economic concerns in poultry industries worldwide. These infections cause chronic respiratory disease and/or synovitis in chickens and turkeys leading to reduced production and increased mortality rates. The live attenuated vaccine strain MS-H (Vaxsafe® MS), commonly used for protection against M. synoviae infection in many countries, contains 32 single nucleotide variations compared to its wildtype parent strain, 86079/7NS. Genomic analysis of vaccine strains reisolated from flocks following the administration of MS-H has identified reversions to the original 86079/7NS sequence in the obgE, oppF and gapdh genes. Here, three MS-H field reisolates containing the 86079/7NS genotype in obgE (AS2), obgE and oppF (AB1), and obgE, oppF and gapdh (TS4), as well as the vaccine MS-H and the parental strain 86079/7NS were experimentally inoculated to chickens. The strains were assessed for their ability to infect and elicit immune responses in the recipient chickens, as well as in naïve in-contact chickens. Despite the loss of temperature sensitivity phenotype and colonization of the reisolates in the lower respiratory tract, there was no significant differences detected in the microscopic mucosal thickness of the middle or lower trachea of the inoculated chickens. Concurrent reversions in ObgE, OppF and GAPDH proteins were associated with higher gross air sac lesion scores and increased microscopic upper-tracheal mucosal thickness in chickens directly inoculated with the reisolates following intratracheal administration of a virulent strain of infectious bronchitis virus. The gross air sac lesions of the chickens in-contact with those inoculated with reisolates were not significantly different to those of chickens in-contact with MS-H inoculated chickens, suggesting that horizontal transmission of the reisolates in the poultry flock will not lead to higher pathogenicity or clinical signs. These results suggest a significant role of GAPDH and/or cumulative effect of ObgE, OppF and GAPDH on M. synoviae pathogenicity. Future experiments will be required to investigate the effect of single mutations in gapdh or oppF gene on pathogenicity of M. synoviae.

13.
Microbiol Spectr ; 10(6): e0284522, 2022 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-36318012

RESUMEN

The Mycoplasma synoviae live attenuated vaccine strain MS-H (Vaxsafe MS; Bioproperties Pty., Ltd., Australia) is commonly used around the world to prevent chronic infections caused by M. synoviae in birds and to minimize economic losses in the poultry industry. MS-H is a temperature-sensitive strain that is generated via the chemical mutagenesis of a virulent M. synoviae isolate, 86079/7NS. 32 single nucleotide polymorphisms have been found in the genome of MS-H compared to that of 86079/7NS, including 25 in predicted coding sequences (CDSs). There is limited information on the stability of these mutations in MS-H in vitro during the propagation of the vaccine manufacturing process or in vivo after the vaccination of chickens. Here, we performed a comparative analysis of MS-H genomes after in vitro and in vivo passages under different circumstances. Studying the dynamics of the MS-H population can provide insights into the factors that potentially affect the health of vaccinated birds. The genomes of 11 in vitro laboratory passages and 138 MS-H bird reisolates contained a total of 254 sequence variations. Of these, 39 variations associated with CDSs were detected in more than one genome (range = 2 to 62, median = 2.5), suggesting that these sequences are particularly prone to mutations. From the 25 CDSs containing previously characterized variations between MS-H and 86079/7NS, 7 were identified in the MS-H reisolates and progenies examined here. In conclusion, the MS-H genome contains individual regions that are prone to mutations that enable the restoration of the genotype or the phenotype of wild-type 86079/7NS in those regions. However, accumulated mutations in these regions are rare. IMPORTANCE Preventative measures, such as vaccination, are commonly used for the control of mycoplasmal infections in poultry. A live attenuated vaccine strain (Vaxsafe MS; MS-H; Bioproperties Pty. Ltd., Australia) is used for the prevention of disease caused by M. synoviae in many countries. However, information on the stability of previously characterized mutations in the MS-H genome is limited. In this study, we performed a comparative analysis of the whole-genome sequences of MS-H seeds used for vaccine manufacturing, commercial batches of the vaccine, cultures minimally passaged under small-scale laboratory and large-scale manufacturing conditions, MS-H reisolated from specific-pathogen-free (SPF) chickens that were vaccinated under controlled conditions, and MS-H reisolated from vaccinated commercial poultry flocks around the world. This study provides a comprehensive assessment of genome stability in MS-H after in vitro and in vivo passages under different circumstances and suggests that most of the mutations in the attenuated MS-H vaccine strain are stable.


Asunto(s)
Mycoplasma synoviae , Enfermedades de las Aves de Corral , Animales , Vacunas Atenuadas/genética , Pollos , Vacunas Bacterianas , Mycoplasma synoviae/genética , Genómica , Enfermedades de las Aves de Corral/prevención & control
14.
Immunol Cell Biol ; 100(10): 761-776, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36106449

RESUMEN

The role of B-cell-activating factor (BAFF) in B-lymphocyte biology has been comprehensively studied, but its contributions to innate immunity remain unclear. Natural killer (NK) cells form the first line of defense against viruses and tumors, and have been shown to be defective in patients with systemic lupus erythematosus (SLE). The link between BAFF and NK cells in the development and progression of SLE remains unstudied. By assessing NK cell numbers in wild-type (WT), BAFF-/- (BAFF deficient), BAFF-R-/- (BAFF receptor deficient), TACI-/- (transmembrane activator and calcium modulator and cyclophilin ligand interactor deficient), BCMA-/- (B-cell maturation antigen deficient) and BAFF transgenic (Tg) mice, we observed that BAFF signaling through BAFF-R was essential for sustaining NK cell numbers in the spleen. However, according to the cell surface expression of CD27 and CD11b on NK cells, we found that BAFF was dispensable for NK cell maturation. Ex vivo and in vivo models showed that NK cells from BAFF-/- and BAFF Tg mice produced interferon-γ and killed tumor cells at a level similar to that in WT mice. Finally, we established that NK cells do not express receptors that interact with BAFF in the steady state or in the BAFF Tg mouse model of SLE. Our findings demonstrate that BAFF has an indirect effect on NK cell homeostasis and no effect on NK cell function.


Asunto(s)
Lupus Eritematoso Sistémico , Proteína Activadora Transmembrana y Interactiva del CAML , Ratones , Animales , Proteína Activadora Transmembrana y Interactiva del CAML/genética , Densidad de Población , Interleucina-4 , Ratones Transgénicos , Células Asesinas Naturales/metabolismo
15.
Avian Pathol ; 51(6): 550-560, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35849061

RESUMEN

Mycoplasma gallisepticum is the primary causative agent of chronic respiratory disease in poultry, and vaccination is the measure most commonly used for its control. Pathological changes caused by M. gallisepticum are mainly observed in the trachea and air sacs, but assessment of air sac lesions is subjective. Standardized parameters for evaluation of pathological changes, and their reproducibility and discrimination in uninfected and infected groups, are critical when assessing the efficacy of M. gallisepticum vaccination. This study reviewed and critically appraised the published literature on evaluation of vaccine efficacy against pathological changes caused by M. gallisepticum in poultry in the trachea and air sacs. A search of four electronic databases, with subsequent manual filtering, identified 23 eligible papers published since 1962 describing the assessment of histopathological changes in the trachea using tracheal lesion scores and/or measurement of tracheal mucosal thicknesses and assessment of gross air sac lesions using lesion scores. Measurement of tracheal lesions proved a more reliable and robust method of assessing disease induced by M. gallisepticum when compared to assessment of air sac lesions, highlighting the importance of including assessment of tracheal lesions as the primary outcome variable in vaccine efficacy studies. In addition, this study also identified the necessity for use of a standardized model for evaluation and reporting on M. gallisepticum vaccines to minimize variations between vaccine efficacy studies and to allow direct comparisons between them.RESEARCH HIGHLIGHTS Tracheal and air sac lesions have been used to assess M. gallisepticum vaccine efficacy.The specific parameters and statistical tests used to compare tracheal and air sac lesions vary greatly.Measures of tracheal lesions are more discriminatory than measures of air sac lesions.A standardized model is needed to evaluate vaccines against infection with M. gallisepticum.


Asunto(s)
Infecciones por Mycoplasma , Mycoplasma gallisepticum , Enfermedades de las Aves de Corral , Animales , Aves de Corral , Tráquea/patología , Reproducibilidad de los Resultados , Enfermedades de las Aves de Corral/patología , Infecciones por Mycoplasma/prevención & control , Infecciones por Mycoplasma/veterinaria , Pollos , Vacunas Bacterianas
16.
J Biol Chem ; 297(4): 101141, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34478713

RESUMEN

The CD8αß heterodimer plays a crucial role in the stabilization between major histocompatibility complex class I molecules (MHC-I) and the T cell receptor (TCR). The interaction between CD8 and MHC-I can be regulated by posttranslational modifications, which are proposed to play an important role in the development of CD8 T cells. One modification that has been proposed to control CD8 coreceptor function is ribosylation. Utilizing NAD+, the ecto-enzyme adenosine diphosphate (ADP) ribosyl transferase 2.2 (ART2.2) catalyzes the addition of ADP-ribosyl groups onto arginine residues of CD8α or ß chains and alters the interaction between the MHC and TCR complexes. To date, only interactions between modified CD8 and classical MHC-I (MHC-Ia), have been investigated and the interaction with non-classical MHC (MHC-Ib) has not been explored. Here, we show that ADP-ribosylation of CD8 facilitates the binding of the liver-restricted nonclassical MHC, H2-Q10, independent of the associated TCR or presented peptide, and propose that this highly regulated binding imposes an additional inhibitory leash on the activation of CD8-expressing cells in the presence of NAD+. These findings highlight additional important roles for nonclassical MHC-I in the regulation of immune responses.


Asunto(s)
ADP-Ribosilación/inmunología , Antígenos CD8/inmunología , Linfocitos T CD8-positivos/inmunología , Antígenos H-2/inmunología , Multimerización de Proteína/inmunología , ADP Ribosa Transferasas/genética , ADP Ribosa Transferasas/inmunología , ADP-Ribosilación/genética , Animales , Antígenos CD8/genética , Antígenos H-2/genética , Hígado/inmunología , Ratones , Ratones Noqueados , Multimerización de Proteína/genética , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología
17.
Clin Chem ; 67(9): 1210-1219, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34077512

RESUMEN

BACKGROUND: Noninvasive prenatal tests (NIPTs) detect fetal chromosomal anomalies with high clinical sensitivity and specificity. We examined the performance of a paired-end sequencing-based NIPT in the detection of genome-wide fetal chromosomal anomalies including common trisomies, sex chromosomal aneuploidies (SCA), rare autosomal aneuploidies (RAAs), and partial deletions/duplications ≥7 Mb. METHODS: Frozen plasma samples from pregnant women were tested using the VeriSeq NIPT Solution v2 assay. All samples were previously tested with a laboratory-developed NIPT and had known clinical outcomes. Individuals performing the sequencing were blinded to clinical outcome data. Clinical sensitivity and specificity were determined for basic (chromosomes 21, 18, 13, X, and Y) and genome-wide screening modes. RESULTS: Of 2335 samples that underwent genome-wide analysis, 28 did not meet QC requirements, resulting in a first-pass assay failure rate of 1.2%. Basic screening analysis, excluding known mosaics, correctly classified 130/130 trisomy 21 samples (sensitivity >99.9%, 95% confidence interval [CI] 97.1%-100%), 41/41 trisomy 18 samples (sensitivity >99.9%, 95% CI 91.4%-100%), and 26/26 trisomy 13 samples (sensitivity >99.9%, 95% CI 87.1%-100%) with 6 false-positive results; specificities ≥99.90% were reported for all 3 trisomies. Concordance for SCAs ranged from 90.5%-100%. Genome-wide screening analysis including known mosaics correctly classified 27/28 RAAs and 20/27 partial deletions/duplications with a specificity of 99.80% for both anomalies, and an overall genome-wide specificity for all anomalies of 99.34%. CONCLUSIONS: The VeriSeq NIPT Solution v2 assay enables accurate identification of fetal aneuploidy, allowing detection of genome-wide fetal chromosomal anomalies with high clinical sensitivities and specificities and a low assay failure rate.Clinical Trial Notification [CTN] identification number [ID]: CT-2018-CTN-01585-1 v1, Protocol: NIPT T05 002.


Asunto(s)
Trastornos de los Cromosomas , Pruebas Prenatales no Invasivas , Aneuploidia , Trastornos de los Cromosomas/diagnóstico , Trastornos de los Cromosomas/genética , Femenino , Humanos , Embarazo , Diagnóstico Prenatal/métodos , Análisis de Secuencia de ADN/métodos , Trisomía , Síndrome de la Trisomía 13/diagnóstico , Síndrome de la Trisomía 18/diagnóstico
18.
Magn Reson Med ; 86(2): 738-753, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33749017

RESUMEN

PURPOSE: Most voxels in white matter contain multiple fiber populations with different orientations and levels of myelination. Conventional T1 mapping measures 1 T1 value per voxel, representing a weighted average of the multiple tract T1 times. Inversion-recovery diffusion-weighted imaging (IR-DWI) allows the T1 times of multiple tracts in a voxel to be disentangled, but the scan time is prohibitively long. Recently, slice-shuffled IR-DWI implementations have been proposed to significantly reduce scan time. In this work, we demonstrate that we can measure tract-specific T1 values in the whole brain using simultaneous multi-slice slice-shuffled IR-DWI at 3T. METHODS: We perform simulations to evaluate the accuracy and precision of our crossing fiber IR-DWI signal model for various fiber parameters. The proposed sequence and signal model are tested in a phantom consisting of crossing asparagus pieces doped with gadolinium to vary T1 , and in 2 human subjects. RESULTS: Our simulations show that tract-specific T1 times can be estimated within 5% of the nominal fiber T1 values. Tract-specific T1 values were resolved in subvoxel 2 fiber crossings in the asparagus phantom. Tract-specific T1 times were resolved in 2 different tract crossings in the human brain where myelination differences have previously been reported; the crossing of the cingulum and genu of the corpus callosum and the crossing of the corticospinal tract and pontine fibers. CONCLUSION: Whole-brain tract-specific T1 mapping is feasible using slice-shuffled IR-DWI at 3T. This technique has the potential to improve the microstructural characterization of specific tracts implicated in neurodevelopment, aging, and demyelinating disorders.


Asunto(s)
Sustancia Blanca , Encéfalo/diagnóstico por imagen , Cuerpo Calloso , Imagen de Difusión por Resonancia Magnética , Humanos , Tractos Piramidales , Sustancia Blanca/diagnóstico por imagen
19.
Vaccines (Basel) ; 8(4)2020 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-33228065

RESUMEN

Salmonella Typhimurium is among the most common causes of bacterial foodborne gastrointestinal disease in humans. Food items containing raw or undercooked eggs are frequently identified during traceback investigation as the source of the bacteria. Layer hens can become persistently infected with Salmonella Typhimurium and intermittently shed the bacteria over the course of their productive lifetime. Eggs laid in a contaminated environment are at risk of potential exposure to bacteria. Thus, mitigating the bacterial load on farms aids in the protection of the food supply chain. Layer hen producers use a multifaceted approach for reducing Salmonella on farms, including the all-in-all-out management strategy, strict biosecurity, sanitization, and vaccination. The use of live attenuated Salmonella vaccines is favored because they elicit a broader host immune response than killed or inactivated vaccines that have been demonstrated to provide cross-protection against multiple serovars. Depending on the vaccine, two to three doses of Salmonella Typhimurium vaccines are generally administered to layer hens within the first few weeks. The productive life of a layer hen, however, can exceed 70 weeks and it is unclear whether current vaccination regimens are effective for that extended period. The objective of this review is to highlight layer hen specific challenges that may affect vaccine efficacy.

20.
Genome Biol ; 21(1): 140, 2020 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-32539747

RESUMEN

BACKGROUND: The type I interferon (IFN) response is an ancient pathway that protects cells against viral pathogens by inducing the transcription of hundreds of IFN-stimulated genes. Comprehensive catalogs of IFN-stimulated genes have been established across species and cell types by transcriptomic and biochemical approaches, but their antiviral mechanisms remain incompletely characterized. Here, we apply a combination of quantitative proteomic approaches to describe the effects of IFN signaling on the human proteome, and apply protein correlation profiling to map IFN-induced rearrangements in the human protein-protein interaction network. RESULTS: We identify > 26,000 protein interactions in IFN-stimulated and unstimulated cells, many of which involve proteins associated with human disease and are observed exclusively within the IFN-stimulated network. Differential network analysis reveals interaction rewiring across a surprisingly broad spectrum of cellular pathways in the antiviral response. We identify IFN-dependent protein-protein interactions mediating novel regulatory mechanisms at the transcriptional and translational levels, with one such interaction modulating the transcriptional activity of STAT1. Moreover, we reveal IFN-dependent changes in ribosomal composition that act to buffer IFN-stimulated gene protein synthesis. CONCLUSIONS: Our map of the IFN interactome provides a global view of the complex cellular networks activated during the antiviral response, placing IFN-stimulated genes in a functional context, and serves as a framework to understand how these networks are dysregulated in autoimmune or inflammatory disease.


Asunto(s)
Interacciones Huésped-Patógeno/inmunología , Interferón Tipo I/metabolismo , Mapas de Interacción de Proteínas , Proteoma , Virosis/metabolismo , Humanos , Proteómica , Proteínas Ribosómicas/metabolismo , Transducción de Señal
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