RESUMEN
SARS-CoV-2 (CoV2) infected, asymptomatic individuals are an important contributor to COVID transmission. CoV2-specific immunoglobulin (Ig)-as generated by the immune system following infection or vaccination-has helped limit CoV2 transmission from asymptomatic individuals to susceptible populations (e.g. elderly). Here, we describe the relationships between COVID incidence and CoV2 lineage, viral load, saliva Ig levels (CoV2-specific IgM, IgA and IgG), and ACE2 binding inhibition capacity in asymptomatic individuals between January 2021 and May 2022. These data were generated as part of a large university COVID monitoring program in Ohio, United States of America, and demonstrate that COVID incidence among asymptomatic individuals occurred in waves which mirrored those in surrounding regions, with saliva CoV2 viral loads becoming progressively higher in our community until vaccine mandates were established. Among the unvaccinated, infection with each CoV2 lineage (pre-Omicron) resulted in saliva Spike-specific IgM, IgA, and IgG responses, the latter increasing significantly post-infection and being more pronounced than N-specific IgG responses. Vaccination resulted in significantly higher Spike-specific IgG levels compared to unvaccinated infected individuals, and uninfected vaccinees' saliva was more capable of inhibiting Spike function. Vaccinees with breakthrough Delta infections had Spike-specific IgG levels comparable to those of uninfected vaccinees; however, their ability to inhibit Spike binding was diminished. These data are consistent with COVID vaccines having achieved hoped-for effects in our community, including the generation of mucosal antibodies that inhibit Spike and lower community viral loads, and suggest breakthrough Delta infections were not due to an absence of vaccine-elicited Ig, but instead limited Spike binding activity in the face of high community viral loads.
Asunto(s)
Formación de Anticuerpos , COVID-19 , Anciano , Humanos , COVID-19/epidemiología , SARS-CoV-2 , Saliva , Universidades , Infección Irruptiva , Inmunoglobulina A , Inmunoglobulina G , Inmunoglobulina MRESUMEN
Ischemic myelomalacia secondary to fibrocartilaginous emboli (FCE) is an idiopathic disease in humans and animals. On the other hand, congenital spinal cord malformations result from neural tube defects in fetal development (ie, spinal dysraphism), with structural anomalies referred to collectively as myelodysplasia. Spinal dysraphisms are frequently accompanied by skin and vertebral abnormalities because of the embryogenic relationship. In this observational case study, we report the pathologic findings of 13, 18- to 24-weeks-old pigs from a large conventional operation that presented with acute paraparesis. Ischemic myelomalacia secondary to FCE was observed in 5 of 13 examined pigs. Congenital spinal cord malformations located between the caudal thoracic and sacral spinal cord were identified in 7 pigs, with structural abnormalities that ranged from diplomyelia/split cord malformation to segmental spinal dysgenesis (myelodysplasia) to caudal agenesis. Concurrent myelomalacia and congenital spinal cord malformations in the same or different sites were noted in 2 pigs. No spinal lesion was observed in 3 pigs. Although gross vertebral abnormalities were not observed herein, intervertebral instability due to minor defects in the articular facets, as well as other unidentified factors, is suspected to contribute high incidence of FCE. It is likely that these congenital malformations were previously underdiagnosed or are possibly new conditions associated with continuous inbreeding and genetic improvement in the modern swine industry.
Asunto(s)
Disrafia Espinal , Enfermedades de los Porcinos , Animales , Isquemia/patología , Isquemia/veterinaria , Imagen por Resonancia Magnética , Médula Espinal/patología , Disrafia Espinal/diagnóstico , Disrafia Espinal/patología , Disrafia Espinal/veterinaria , Columna Vertebral/anomalías , Porcinos , Enfermedades de los Porcinos/patologíaRESUMEN
Wastewater-based epidemiology is an effective tool for monitoring infectious disease spread or illicit drug use within communities. At the Ohio State University, we conducted a SARS-CoV-2 wastewater surveillance program in the 2020-2021 academic year and compared results with the university-required weekly COVID-19 saliva testing to monitor COVID-19 infection prevalence in the on-campus residential communities. The objectives of the study were to rapidly track trends in the wastewater SARS-CoV-2 gene concentrations, analyze the relationship between case numbers and wastewater signals when adjusted using human fecal viral indicator concentrations (PMMoV, crAssphage) in wastewater, and investigate the relationship of the SARS-CoV-2 gene concentrations with wastewater parameters. SARS-CoV-2 nucleocapsid and envelope (N1, N2, and E) gene concentrations, determined with reverse transcription droplet digital PCR, were used to track SARS-CoV-2 viral loads in dormitory wastewater once a week at 6 sampling sites across the campus during the fall semester in 2020. During the following spring semester, research was focused on SARS-CoV2 N2 gene concentrations at 5 sites sampled twice a week. Spearman correlations both with and without adjusting using human fecal viral indicators showed a significant correlation (p < 0.05) between human COVID-19 positive case counts and wastewater SARS-CoV-2 gene concentrations. Spearman correlations showed significant relationships between N1 gene concentrations and both TSS and turbidity, and between E gene concentrations and both pH and turbidity. These results suggest that wastewater signal increases with the census of infected individuals, in which the majority are asymptomatic, with a statistically significant (p-value <0.05) temporal correlation. The study design can be utilized as a platform for rapid trend tracking of SARS-CoV-2 variants and other diseases circulating in various communities.
Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Humanos , ARN Viral/genética , SARS-CoV-2/genética , Universidades , Aguas Residuales , Monitoreo Epidemiológico Basado en Aguas ResidualesRESUMEN
UNLABELLED: Human norovirus (NoV) accounts for 95% of nonbacterial gastroenteritis worldwide. Currently, there is no vaccine available to combat human NoV as it is not cultivable and lacks a small-animal model. Recently, we demonstrated that recombinant vesicular stomatitis virus (rVSV) expressing human NoV capsid protein (rVSV-VP1) induced strong immunities in mice (Y. Ma and J. Li, J. Virol. 85:2942-2952, 2011). To further improve the safety and efficacy of the vaccine candidate, heat shock protein 70 (HSP70) was inserted into the rVSV-VP1 backbone vector. A second construct was generated in which the firefly luciferase (Luc) gene was inserted in place of HSP70 as a control for the double insertion. The resultant recombinant viruses (rVSV-HSP70-VP1 and rVSV-Luc-VP1) were significantly more attenuated in cell culture and viral spread in mice than rVSV-VP1. At the inoculation dose of 1.0 × 10(6) PFU, rVSV-HSP70-VP1 triggered significantly higher vaginal IgA than rVSV-VP1 and significantly higher fecal and vaginal IgA responses than rVSV-Luc-VP1, although serum IgG and T cell responses were similar. At the inoculation dose of 5.0 × 10(6) PFU, rVSV-HSP70-VP1 stimulated significantly higher T cell, fecal, and vaginal IgA responses than rVSV-VP1. Fecal and vaginal IgA responses were also significantly increased when combined vaccination of rVSV-VP1 and rVSV-HSP70 was used. Collectively, these data indicate that (i) insertion of an additional gene (HSP70 or Luc) into the rVSV-VP1 backbone further attenuates the VSV-based vaccine in vitro and in vivo, thus improving the safety of the vaccine candidate, and (ii) HSP70 enhances the human NoV-specific mucosal and T cell immunities triggered by a VSV-based human NoV vaccine. IMPORTANCE: Human norovirus (NoV) is responsible for more than 95% of acute nonbacterial gastroenteritis worldwide. Currently, there is no vaccine for this virus. Development of a live attenuated vaccine for human NoV has not been possible because it is uncultivable. Thus, a live vector-based vaccine may provide an alternative vaccine strategy. In this study, we developed a vesicular stomatitis virus (VSV)-based human NoV vaccine candidate. We constructed rVSV-HSP70-VP1, coexpressing heat shock protein (HSP70) and capsid (VP1) genes of human NoV, and rVSV-Luc-VP1, coexpressing firefly luciferase (Luc) and VP1 genes. We found that VSVs with a double gene insertion were significantly more attenuated than VSV with a single VP1 insertion (rVSV-VP1). Furthermore, we found that coexpression or coadministration of HSP70 from VSV vector significantly enhanced human NoV-specific mucosal immunity. Collectively, we developed an improved live vectored vaccine candidate for human NoV which will be useful for future clinical studies.
Asunto(s)
Vectores Genéticos , Proteínas HSP70 de Choque Térmico/inmunología , Inmunidad Mucosa , Norovirus/inmunología , Vesiculovirus/genética , Vacunas Virales/inmunología , Animales , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Femenino , Tracto Gastrointestinal/inmunología , Inmunoglobulina A/análisis , Inmunoglobulina G/sangre , Ratones , Ratones Endogámicos BALB C , Norovirus/genética , Linfocitos T/inmunología , Vacunas Atenuadas/administración & dosificación , Vacunas Atenuadas/genética , Vacunas Atenuadas/inmunología , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Vagina/inmunología , Vacunas Virales/administración & dosificación , Vacunas Virales/genéticaRESUMEN
UNLABELLED: One role of mRNA cap guanine-N-7 (G-N-7) methylation is to facilitate the efficient translation of mRNA. The role of mRNA cap ribose 2'-O methylation is enigmatic, although recent work has implicated this as a signature to avoid detection of RNA by the innate immune system (S. Daffis, K. J. Szretter, J. Schriewer, J. Q. Li, S. Youn, J. Errett, T. Y. Lin, S. Schneller, R. Zust, H. P. Dong, V. Thiel, G. C. Sen, V. Fensterl, W. B. Klimstra, T. C. Pierson, R. M. Buller, M. Gale, P. Y. Shi, M. S. Diamond, Nature 468:452-456, 2010, doi:10.1038/nature09489). Working with vesicular stomatitis virus (VSV), we previously showed that a panel of recombinant VSVs carrying mutations at a predicted methyltransferase catalytic site (rVSV-K1651A, -D1762A, and -E1833Q) or S-adenosylmethionine (SAM) binding site (rVSV-G1670A, -G1672A, and -G4A) were defective in cap methylation and were also attenuated for growth in cell culture. Here, we analyzed the virulence of these recombinants in mice. We found that rVSV-K1651A, -D1762A, and -E1833Q, which are defective in both G-N-7 and 2'-O methylation, were highly attenuated in mice. All three viruses elicited a high level of neutralizing antibody and provided full protection against challenge with the virulent VSV. In contrast, mice inoculated with rVSV-G1670A and -G1672A, which are defective only in G-N-7 methylation, were attenuated in vivo yet retained a low level of virulence. rVSV-G4A, which is completely defective in both G-N-7 and 2'-O methylation, also exhibited low virulence in mice despite the fact that productive viral replication was not detected in lung and brain. Taken together, our results suggest that abrogation of viral mRNA cap methylation can serve as an approach to attenuate VSV, and perhaps other nonsegmented negative-strand RNA viruses, for potential application as vaccines and viral vectors. IMPORTANCE: Nonsegmented negative-sense (NNS) RNA viruses include a wide range of significant human, animal, and plant pathogens. For many of these viruses, there are no vaccines or antiviral drugs available. mRNA cap methylation is essential for mRNA stability and efficient translation. Our current understanding of mRNA modifications of NNS RNA viruses comes largely from studies of vesicular stomatitis virus (VSV). In this study, we showed that recombinant VSVs (rVSVs) defective in mRNA cap methylation were attenuated in vitro and in vivo. In addition, these methyltransferase (MTase)-defective rVSVs triggered high levels of antibody responses and provided complete protection against VSV infection. Thus, this study will not only contribute to our understanding of the role of mRNA cap MTase in viral pathogenesis but also facilitate the development of new live attenuated vaccines for VSV, and perhaps other NNS RNA viruses, by inhibiting viral mRNA cap methylation.
Asunto(s)
Caperuzas de ARN/metabolismo , ARN Mensajero/metabolismo , ARN Viral/metabolismo , Estomatitis Vesicular/virología , Virus de la Estomatitis Vesicular Indiana/genética , Virus de la Estomatitis Vesicular Indiana/metabolismo , Animales , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Encéfalo/patología , Encéfalo/virología , Línea Celular , Virus Defectuosos/genética , Virus Defectuosos/metabolismo , Femenino , Dosificación Letal Mediana , Pulmón/patología , Pulmón/virología , Metilación , Metiltransferasas/deficiencia , Metiltransferasas/genética , Metiltransferasas/metabolismo , Ratones , Fenotipo , Estomatitis Vesicular/inmunología , Estomatitis Vesicular/patología , Virus de la Estomatitis Vesicular Indiana/inmunología , Virus de la Estomatitis Vesicular Indiana/patogenicidad , Carga Viral , Virulencia , Replicación ViralRESUMEN
Male transgenic adenocarcinoma of the mouse prostate (TRAMP) mice are frequently used in prostate cancer research because their prostates consistently develop a series of preneoplastic and neoplastic lesions. Disease progression in TRAMP mouse prostates culminates in metastatic, poorly differentiated carcinomas with neuroendocrine features. The androgen dependence of the rat probasin promoter largely limits transgene expression to the prostatic epithelium. However, extra-prostatic transgene-positive lesions have been described in TRAMP mice, including renal tubuloacinar carcinomas, neuroendocrine carcinomas of the urethra, and phyllodes-like tumors of the seminal vesicle. Here, we describe the histologic and immunohistochemical features of 2 novel extra-prostatic lesions in TRAMP mice: primary anaplastic tumors of uncertain cell origin in the midbrain and poorly differentiated adenocarcinomas of the submandibular salivary gland. These newly characterized tumors apparently result from transgene expression in extra-prostatic locations rather than representing metastatic prostate neoplasms because lesions were identified in both male and female mice and in male TRAMP mice without histologically apparent prostate tumors. In this article, we also calculate the incidences of the urethral carcinomas and renal tubuloacinar carcinomas, further elucidate the biological behavior of the urethral carcinomas, and demonstrate the critical importance of complete necropsies even when evaluating presumably well characterized phenotypes in genetically engineered mice.
Asunto(s)
Adenocarcinoma/genética , Neoplasias de la Próstata/genética , Transgenes/genética , Adenocarcinoma/patología , Animales , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/secundario , Femenino , Neoplasias Renales/genética , Neoplasias Renales/patología , Neoplasias Renales/secundario , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Necrosis , Neoplasias de la Próstata/patología , Neoplasias de la Glándula Submandibular/genética , Neoplasias de la Glándula Submandibular/patología , Neoplasias de la Glándula Submandibular/secundario , Neoplasias Uretrales/genética , Neoplasias Uretrales/patología , Neoplasias Uretrales/secundarioRESUMEN
The major inducible 70-kDa heat shock protein (hsp70) protects against measles virus (MeV) neurovirulence in the mouse that is caused by a cell-associated noncytolytic neuronal infection. Protection is type I interferon (IFN) dependent, and we have established a novel axis of antiviral immunity in which hsp70 is released from virus-infected neurons to induce IFN-ß in macrophages. The present work used vesicular stomatitis virus (VSV) to establish the relevance of hsp70-dependent antiviral immunity to fulminant cytopathic neuronal infections. In vitro, hsp70 that was constitutively expressed in mouse neuronal cells caused a modest increase in VSV replication. Infection induced an early extracellular release of hsp70 from viable cells, and the release was progressive, increasing with virus-induced apoptosis and cell lysis. The impact of this VSV-hsp70 interaction on neurovirulence was established in weanling male hsp70 transgenic and nontransgenic mice. Constitutive expression of hsp70 in neurons of transgenic mice enhanced viral clearance from brain and reduced mortality, and it was correlated with enhanced expression of type I IFN mRNA. Nontransgenic mice were also protected against neurovirulence and expressed increased type I IFN mRNA in brain when hsp70 was expressed by a recombinant VSV (rVSV-hsp70), indicating that hsp70 in the virus-infected cell is sufficient for host protection. In vitro data confirmed extracellular release of hsp70 from cells infected with rVSV-hsp70 and also showed that viral replication is not enhanced when hsp70 is expressed in this manner, suggesting that hsp70-mediated protection in vivo is not dependent on stimulatory effects of hsp70 on virus gene expression.
Asunto(s)
Apoptosis , Encéfalo/virología , Proteínas HSP70 de Choque Térmico/metabolismo , Inmunidad Celular/inmunología , Neuronas/virología , Estomatitis Vesicular/patología , Virus de la Estomatitis Vesicular Indiana/fisiología , Animales , Western Blotting , Encéfalo/inmunología , Encéfalo/patología , Proliferación Celular , Proteínas HSP70 de Choque Térmico/genética , Interferón Tipo I/genética , Interferón Tipo I/metabolismo , Macrófagos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuronas/inmunología , Neuronas/patología , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Estomatitis Vesicular/inmunología , Estomatitis Vesicular/virología , Replicación Viral/inmunologíaRESUMEN
The major inducible 70-kDa heat shock protein (hsp70) is host protective in a mouse model of measles virus (MeV) brain infection. Transgenic constitutive expression of hsp70 in neurons, the primary target of MeV infection, abrogates neurovirulence in neonatal H-2(d) congenic C57BL/6 mice. A significant level of protection is retained after depletion of T lymphocytes, implicating innate immune mechanisms. The focus of the present work was to elucidate the basis for hsp70-dependent innate immunity using this model. Transcriptome analysis of brains from transgenic (TG) and nontransgenic (NT) mice 5 days after infection identified type I interferon (IFN) signaling, macrophage activation, and antigen presentation as the main differences linked to survival. The pivotal role of type I IFN in hsp70-mediated protection was demonstrated in mice with a genetically disrupted type I IFN receptor (IFNAR(-/-)), where IFNAR(-/-) eliminated the difference in survival between TG and NT mice. Brain macrophages, not neurons, are the predominant source of type I IFN in the virus-infected brain, and in vitro studies provided a mechanistic basis by which MeV-infected neurons can induce IFN-ß in uninfected microglia in an hsp70-dependent manner. MeV infection induced extracellular release of hsp70 from mouse neuronal cells that constitutively express hsp70, and extracellular hsp70 induced IFN-ß transcription in mouse microglial cells through Toll-like receptors 2 and 4. Collectively, our results support a novel axis of type I IFN-dependent antiviral immunity in the virus-infected brain that is driven by hsp70.
Asunto(s)
Encéfalo/inmunología , Proteínas HSP70 de Choque Térmico/inmunología , Interferón Tipo I/inmunología , Virus del Sarampión/inmunología , Sarampión/inmunología , Transducción de Señal , Animales , Encéfalo/patología , Encéfalo/virología , Modelos Animales de Enfermedad , Macrófagos/inmunología , Masculino , Sarampión/virología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Receptor de Interferón alfa y beta/deficiencia , Análisis de Supervivencia , TranscriptomaRESUMEN
A 28-year-old, female umbrella cockatoo (Cacatua alba) was evaluated because of lethargy, anorexia, regurgitation, and coelomic swelling of 6 month's duration, which corresponded to cessation of egg laying. Radiographs and ultrasound examination demonstrated extensive deposits of coelomic fat and an enlarged oviduct. Exploratory celiotomy demonstrated copious amounts of firm, nodular fat completely surrounding the gastrointestinal tract, resulting in extensive chronic adhesions between intestinal loops. Free yolk was present in the cranial left coelom, yolk coelomitis was diagnosed, and a salpingohysterectomy was performed. Two days after surgery, the bird stopped passing feces and began regurgitating after eating, and a colonic obstruction was demonstrated via contrast radiography. Euthanasia was elected, and necropsy revealed an obstruction of the distal colon caused by extraluminal compression by adhesions of firm, nodular fat. Histologic examination demonstrated extensive fat necrosis with granulomatous inflammation, characterized by cords of necrotic fat surrounded by multinucleated giant cells and epithelioid macrophages with scattered lymphocytes and plasma cells and rare heterophils. The clinical signs, gross lesions, and histologic lesions are characteristic of massive fat necrosis (lipogranulomatosis) in ruminants and mesenteric panniculitis in humans and companion mammals. This is the first report, to our knowledge, of this disease in psittacine birds.
RESUMEN
Mass mortality events in wildlife can be indications of an emerging infectious disease. During the spring and summer of 2021, hundreds of dead passerines were reported across the eastern US. Birds exhibited a range of clinical signs including swollen conjunctiva, ocular discharge, ataxia, and nystagmus. As part of the diagnostic investigation, high-throughput metagenomic next-generation sequencing was performed across three molecular laboratories on samples from affected birds. Many potentially pathogenic microbes were detected, with bacteria forming the largest proportion; however, no singular agent was consistently identified, with many of the detected microbes also found in unaffected (control) birds and thus considered to be subclinical infections. Congruent results across laboratories have helped drive further investigation into alternative causes, including environmental contaminants and nutritional deficiencies. This work highlights the utility of metagenomic approaches in investigations of emerging diseases and provides a framework for future wildlife mortality events.
Asunto(s)
Enfermedades Transmisibles Emergentes , Pájaros Cantores , Animales , Animales Salvajes , Metagenoma , Bacterias/genética , Enfermedades Transmisibles Emergentes/veterinaria , Metagenómica/métodosRESUMEN
The measles virus (MeV) phosphoprotein (P) tethers the polymerase to the nucleocapsid template for transcription and genome replication. Binding of P to nucleocapsid is mediated by the X domain of P (XD) and a conserved sequence (Box-2) within the C-terminal domain of the nucleoprotein (N(TAIL)). XD binding induces N(TAIL) α-helical folding, which in turn has been proposed to stabilize the polymerase-nucleocapsid complex, with cycles of binding and release required for transcription and genome replication. The current work directly assessed the relationships among XD-induced N(TAIL) folding, XD-N(TAIL) binding affinity, and polymerase activity. Amino acid substitutions that abolished XD-induced N(TAIL) α-helical folding were created within Box-2 of Edmonston MeV N(TAIL). Polymerase activity in minireplicons was maintained despite a 35-fold decrease in XD-N(TAIL) binding affinity or reduction/loss of XD-induced N(TAIL) alpha-helical folding. Recombinant infectious virus was recovered for all mutants, and transcriptase elongation rates remained within a 1.7-fold range of parent virus. Box-2 mutations did however impose a significant cost to infectivity, reflected in an increase in the amount of input genome required to match the infectivity of parent virus. Diminished infectivity could not be attributed to changes in virion protein composition or production of defective interfering particles, where changes from parent virus were within a 3-fold range. The results indicated that MeV polymerase activity, but not infectivity, tolerates amino acid changes in the XD-binding region of the nucleoprotein. Selectional pressure for conservation of the Box-2 sequence may thus reflect a role in assuring the fidelity of polymerase functions or the assembly of viral particles required for optimal infectivity.
Asunto(s)
Virus del Sarampión/fisiología , Proteínas de la Nucleocápside/química , Fosfoproteínas/química , Secuencias de Aminoácidos , Sustitución de Aminoácidos , Animales , Chlorocebus aethiops , ARN Polimerasas Dirigidas por ADN/química , ARN Polimerasas Dirigidas por ADN/genética , Regulación Viral de la Expresión Génica , Genoma Viral , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Virus del Sarampión/enzimología , Virus del Sarampión/genética , Datos de Secuencia Molecular , Complejos Multiproteicos/química , Mutagénesis Sitio-Dirigida , Fosfoproteínas/genética , Unión Proteica , Pliegue de Proteína , Dominios y Motivos de Interacción de Proteínas , Estabilidad Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Transcripción Genética , Células Vero , Carga Viral , Virión/metabolismo , Replicación ViralRESUMEN
The inhibition of vaccination by maternal antibodies is a widely observed phenomenon in human and veterinary medicine. Maternal antibodies are known to suppress the B-cell response. This is similar to antibody feedback mechanism studies where passively transferred antibody inhibits the B-cell response against particulate antigens because of epitope masking. In the absence of experimental data addressing the mechanism underlying inhibition by maternal antibodies, it has been suggested that epitope masking explains the inhibition by maternal antibodies, too. Here we report that in the cotton rat model of measles virus (MV) vaccination passively transferred MV-specific immunoglobulin G inhibit B-cell responses through cross-linking of the B-cell receptor with FcγRIIB. The extent of inhibition increases with the number of antibodies engaging FcγRIIB and depends on the Fc region of antibody and its isotype. This inhibition can be partially overcome by injection of MV-specific monoclonal IgM antibody. IgM stimulates the B-cell directly through cross-linking the B-cell receptor via complement protein 3d and antigen to the complement receptor 2 signaling complex. These data demonstrate that maternal antibodies inhibit B-cell responses by interaction with the inhibitory/regulatory FcγRIIB receptor and not through epitope masking.
Asunto(s)
Anticuerpos Antivirales/inmunología , Linfocitos B/inmunología , Inmunoglobulina G/inmunología , Intercambio Materno-Fetal/inmunología , Vacuna Antisarampión/farmacología , Vacunación , Animales , Anticuerpos Monoclonales de Origen Murino/inmunología , Anticuerpos Monoclonales de Origen Murino/farmacología , Complemento C3d/inmunología , Epítopos/inmunología , Femenino , Humanos , Inmunoglobulina M/inmunología , Inmunoglobulina M/farmacología , Recubrimiento Inmunológico/efectos de los fármacos , Recubrimiento Inmunológico/inmunología , Intercambio Materno-Fetal/efectos de los fármacos , Embarazo , Receptores de Complemento 3d/inmunología , Receptores de IgG/inmunología , SigmodontinaeRESUMEN
The Henipavirus genome is encapsidated by the nucleoprotein (N) within a helical nucleocapsid that recruits the polymerase complex via the phosphoprotein (P). In a previous study, we reported that in henipaviruses, the N-terminal domain of the phosphoprotein and the C-terminal domain of the nucleoprotein (N(TAIL)) are both intrinsically disordered. Here we show that Henipavirus N(TAIL) domains are also disordered in the context of full-length nucleoproteins. We also report the cloning, purification, and characterization of the C-terminal X domains (P(XD)) of Henipavirus phosphoproteins. Using isothermal titration calorimetry, we show that N(TAIL) and P(XD) form a 1:1 stoichiometric complex that is stable under NaCl concentrations as high as 1 M and has a K(D) in the µM range. Using far-UV circular dichroism and nuclear magnetic resonance, we show that P(XD) triggers an increase in the α-helical content of N(TAIL). Using fluorescence spectroscopy, we show that P(XD) has no impact on the chemical environment of a Trp residue introduced at position 527 of the Henipavirus N(TAIL) domain, thus arguing for the lack of stable contacts between the C termini of N(TAIL) and P(XD). Finally, we present a tentative structural model of the N(TAIL)-P(XD) interaction in which a short, order-prone region of N(TAIL) (α-MoRE; amino acids 473-493) adopts an α-helical conformation and is embedded between helices α2 and α3 of P(XD), leading to a relatively small interface dominated by hydrophobic contacts. The present results provide the first detailed experimental characterization of the N-P interaction in henipaviruses and designate the N(TAIL)-P(XD) interaction as a valuable target for rational antiviral approaches.
Asunto(s)
Henipavirus/química , Modelos Moleculares , Nucleoproteínas/química , Fosfoproteínas/química , Proteínas Virales/química , Henipavirus/genética , Nucleoproteínas/genética , Fosfoproteínas/genética , Estructura Cuaternaria de Proteína , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Virales/genéticaRESUMEN
Both endovascular repair (EVR) and open repair (OR) surgery of thoraco-abdominal aortic aneurysms cause spinal cord (SC) injury that can lead to paraparesis or paraplegia. It has been assumed that mechanisms responsible for SC damage after EVR are similar to those after OR. This pilot study compared the pathophysiology of SC injury after EVR versus OR using a newly developed EVR dog model. An increasing number of stents similar to those used in patients were inserted in the aorta of three dogs to ensure thoracic or thoracic plus lumbar coverage. The aorta of OR dogs was cross-clamped for 45 min. Behavior assessment demonstrated unique patterns of proprioceptive ataxia and evolving paraparesis in EVR versus irreversible paraplegia in OR. MRI showed posterior signal in lumbar SC after EVR versus central cord edema after OR. Histopathology showed white matter edema in L3-L5 localized to the dorsal column medial lemniscus area associated with loss of myelin basic protein but not neurons after EVR, versus massive neuronal loss in the gray matter in L3-L5 after OR. Metabolome analysis demonstrates a distinctive chemical fingerprint of cellular processes in both interventions. Our results call for the development of new therapeutics tailored to these distinct pathophysiologic findings.
Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/efectos adversos , Prótesis Vascular/efectos adversos , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Complicaciones Posoperatorias/etiología , Traumatismos de la Médula Espinal/etiología , Stents/efectos adversos , Animales , Conducta Animal , Angiografía por Tomografía Computarizada/métodos , Modelos Animales de Enfermedad , Perros , Imagen por Resonancia Magnética/métodos , Masculino , Metaboloma , Paraplejía/etiología , Proyectos Piloto , Complicaciones Posoperatorias/diagnóstico por imagen , Médula Espinal/diagnóstico por imagen , Traumatismos de la Médula Espinal/diagnóstico por imagen , Resultado del TratamientoRESUMEN
The major inducible 70 kDa heat shock protein (hsp70) binds the measles virus (MeV) nucleocapsid with high affinity in an ATP-dependent manner, stimulating viral transcription and genome replication, and profoundly influencing virulence in mouse models of brain infection. Binding is mediated by two hydrophobic motifs (Box-2 and Box-3) located within the C-terminal domain (N(TAIL)) of the nucleocapsid protein, with N(TAIL) being an intrinsically disordered domain. The current work showed that high affinity hsp70 binding to N(TAIL) requires an hsp40 co-chaperone that interacts primarily with the hsp70 nucleotide binding domain (NBD) and displays no significant affinity for N(TAIL). Hsp40 directly enhanced hsp70 ATPase activity in an N(TAIL)-dependent manner, and formation of hsp40-hsp70-N(TAIL) intracellular complexes required the presence of N(TAIL) Box-2 and 3. Results are consistent with the functional interplay between hsp70 nucleotide and substrate binding domains (SBD), where ATP hydrolysis is rate limiting to high affinity binding to client proteins and is enhanced by hsp40. As such, hsp40 is an essential variable in understanding the outcome of MeV-hsp70 interactions.
Asunto(s)
Proteínas del Choque Térmico HSP40/química , Proteínas del Choque Térmico HSP40/metabolismo , Proteínas HSP70 de Choque Térmico/química , Proteínas HSP70 de Choque Térmico/metabolismo , Nucleoproteínas/química , Nucleoproteínas/metabolismo , Proteínas Virales/química , Proteínas Virales/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Línea Celular , Proteínas del Choque Térmico HSP40/genética , Proteínas HSP70 de Choque Térmico/genética , Ratones , Modelos Moleculares , Proteínas de la Nucleocápside , Nucleoproteínas/genética , Unión Proteica , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Virales/genéticaRESUMEN
In vitro studies show that hsp70 promotes gene expression for multiple viral families, although there are few reports on the in vivo significance of virus-hsp70 interaction. Previously we showed that hsp70-dependent stimulation of Edmonston measles virus (Ed MeV) transcription caused an increased cytopathic effect and mortality in transgenic hsp70-overexpressing C57BL/6 mice (H-2(b)). The response to MeV infection is influenced by the major histocompatibility complex haplotype; H-2(d) mice are resistant to brain infection due to robust antiviral immune responses, whereas H-2(b) mice are susceptible due to deficiencies in this response. We therefore tested the hypothesis that the outcome of MeV-hsp70 interaction may be dependent upon the host H-2 haplotype. The impact of selective neuronal hsp70 overexpression on Ed MeV brain infection was tested with congenic C57BL/10 H-2(d) neonatal mice. In this context, hsp70 overexpression conferred complete protection against virus-induced mortality, compared to >30% mortality in nontransgenic mice. Selective depletion of T-cell populations showed that transgenic mice exhibit a diminished reliance on T cells for protection. Brain transcript analysis indicated enhanced innate immune activation and signaling through Toll-like receptors 2 and 4 at early times postinfection for transgenic infected mice relative to those for nontransgenic infected mice. Collectively, results suggest that hsp70 can enhance innate antiviral immunity through Toll-like receptor signaling, supporting a protective role for physiological responses that enhance tissue levels of hsp70 (e.g., fever), and that the H-2 haplotype determines the effectiveness of this response.
Asunto(s)
Encefalopatías/inmunología , Proteínas del Choque Térmico HSP72/inmunología , Proteínas del Choque Térmico HSP72/metabolismo , Complejo Mayor de Histocompatibilidad/inmunología , Virus del Sarampión/inmunología , Virus del Sarampión/patogenicidad , Sarampión/inmunología , Animales , Encefalopatías/genética , Encefalopatías/metabolismo , Encefalopatías/patología , Células Cultivadas , Femenino , Regulación de la Expresión Génica , Proteínas del Choque Térmico HSP72/genética , Haplotipos , Humanos , Inmunidad Innata/inmunología , Masculino , Sarampión/genética , Sarampión/metabolismo , Sarampión/patología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Tasa de Supervivencia , Subgrupos de Linfocitos T/inmunología , VirulenciaRESUMEN
A 2.5-year-old, female llama with weight loss and lethargy had a packed cell volume (PCV) of 45% which increased to 57% over 3 wk. Transrectal ultrasonography revealed a mass of mixed echogenicity involving the right ovary, which was removed. A histopathological diagnosis of granulosa theca cell tumor was made. This is the first report of its kind in a llama.
Asunto(s)
Camélidos del Nuevo Mundo , Neoplasias Ováricas/veterinaria , Policitemia/veterinaria , Animales , Femenino , Tumor de Células de la Granulosa/diagnóstico , Tumor de Células de la Granulosa/cirugía , Tumor de Células de la Granulosa/veterinaria , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/cirugía , Policitemia/diagnóstico , Policitemia/cirugía , Resultado del TratamientoRESUMEN
rQNestin34.5v.2 is an oncolytic herpes simplex virus 1 (oHSV) that retains expression of the neurovirulent ICP34.5 gene under glioma-selective transcriptional regulation. To prepare an investigational new drug (IND) application, we performed toxicology and efficacy studies of rQNestin34.5v.2 in mice in the presence or absence of the immunomodulating drug cyclophosphamide (CPA). ICP34.5 allows HSV1 to survive interferon and improves viral replication by dephosphorylation of the eIF-2α translation factor. rQNestin34.5v.2 dephosphorylated eIF-2α in human glioma cells, but not in human normal cells, resulting in significantly higher cytotoxicity and viral replication in the former compared to the latter. In vivo toxicity of rQNestin34.5v.2 was compared with that of wild-type F strain in immunocompetent BALB/c mice and athymic mice by multiple routes of administration in the presence or absence of CPA. A likely no observed adverse effect level (NOAEL) dose for intracranial rQNestin34.5v.2 was estimated, justifying a phase 1 clinical trial in recurrent glioma patients (ClinicalTrials.gov: NCT03152318), after successful submission of an IND.
RESUMEN
The number of veterinarians in the United States is inadequate to meet societal needs in biomedical research and public health. Areas of greatest need include translational medical research, veterinary pathology, laboratory-animal medicine, emerging infectious diseases, public health, academic medicine, and production-animal medicine. Veterinarians have unique skill sets that enable them to serve as leaders or members of interdisciplinary research teams involved in basic science and biomedical research with applications to animal or human health. There are too few graduate veterinarians to serve broad national needs in private practice; academia; local, state, and federal government agencies; and private industry. There are no easy solutions to the problem of increasing the number of veterinarians in biomedical research. Progress will require creativity, modification of priorities, broad-based communication, support from faculty and professional organizations, effective mentoring, education in research and alternative careers as part of the veterinary professional curriculum, and recognition of the value of research experience among professional schools' admissions committees. New resources should be identified to improve communication and education, professional and graduate student programs in biomedical research, and support to junior faculty. These actions are necessary for the profession to sustain its viability as an integral part of biomedical research.
Asunto(s)
Investigación Biomédica , Educación en Veterinaria/organización & administración , Criterios de Admisión Escolar , Veterinarios/psicología , Medicina Veterinaria , Animales , Investigación Biomédica/economía , Apoyo Financiero , Humanos , Salud Pública , Estados Unidos , Veterinarios/economía , Medicina Veterinaria/economía , Recursos HumanosRESUMEN
CASE DESCRIPTION: A 2-year-old Thoroughbred filly was evaluated because of hemorrhage from the vulva and suspected hematuria of 5 days' duration. CLINICAL FINDINGS: A primary coagulopathy was ruled out on the basis of results of hematologic testing. Vaginoscopy and cystoscopy revealed a large bleeding mass in the bladder that extended into the vagina, causing marked obliteration of normal urogenital structures and difficulty in urination. Histologic examination of endoscopic and surgical biopsy specimens revealed a poorly differentiated neoplasia likely of mesenchymal origin. Chronic suppurative cystitis caused by Streptococcus zooepidemicus was also diagnosed. TREATMENT AND OUTCOME: The tumor continued to grow despite treatment with doxorubicin and, within 45 days, was causing substantial discomfort and stranguria. Given the grave prognosis, the horse was euthanized. At necropsy, the tumor was found to have caused widespread destruction of the urinary bladder and to have invaded the broad ligament of the uterus. The mass was identified as a poorly differentiated leiomyosarcoma on the basis of results of histologic examination and immunohistochemical staining for alpha-actin. CLINICAL RELEVANCE: Findings suggested that leiomyosarcoma should be considered in the differential diagnosis when examining horses with urogenital bleeding.