Project description:Successful vaccination against smallpox with conventional vaccinia virus is usually determined by the development of a vesicular skin lesion at the site of vaccinia inoculation, called a ‘take’. Although previous vaccination is known to be associated with attenuation of the take, the immunology that underlies a no-take in vaccinia-naïve individuals is not well understood. We hypothesized that antibody profiling of individuals before and after receiving vaccinia would reveal differences between takes and no-takes that may help better understand the phenomenon. Using vaccinia proteome microarrays and recombinant protein ELISAs we first examined the antibody response in vaccinia-naïve individuals that failed to take after receiving different doses of the replication competent smallpox vaccines, DryVax® and APSV. Most that received diluted vaccine failed to respond, whereas 4 other no-takes receiving diluted vaccine, and 4 receiving undiluted vaccine, mounted an antibody response. Interestingly, their antibody profiles were not significantly different from controls that did show a take. However, we did find elevated antibody titers in no-takes prior to receiving DryVax® that was significantly different from takes. Although the sample size studied was small, we conclude the failure to take in responders correlates with pre-existing immunity of unknown etiology that may attenuate the skin reaction in a way similar to previous smallpox vaccination. Antibody profiling was peformed on sera from vaccinees receiving smallpox vaccines, either Wyeth DryVax or Aventis Pasteur Vaccine ('WetVax') in NIH-sponsored clinical trials. These samples comprise 23 vaccinia naïve no-takes, and 50 vaccinia naïve takes and 25 previoulsy vaccinated takes as controls. Samples from d0 (day of vaccination) and at the peak of the antibody repsonse (d28) were taken from each donor and probed in triplicate against the proteome arrays.
Project description:Successful vaccination against smallpox with conventional vaccinia virus is usually determined by the development of a vesicular skin lesion at the site of vaccinia inoculation, called a ‘take’. Although previous vaccination is known to be associated with attenuation of the take, the immunology that underlies a no-take in vaccinia-naïve individuals is not well understood. We hypothesized that antibody profiling of individuals before and after receiving vaccinia would reveal differences between takes and no-takes that may help better understand the phenomenon. Using vaccinia proteome microarrays and recombinant protein ELISAs we first examined the antibody response in vaccinia-naïve individuals that failed to take after receiving different doses of the replication competent smallpox vaccines, DryVax® and APSV. Most that received diluted vaccine failed to respond, whereas 4 other no-takes receiving diluted vaccine, and 4 receiving undiluted vaccine, mounted an antibody response. Interestingly, their antibody profiles were not significantly different from controls that did show a take. However, we did find elevated antibody titers in no-takes prior to receiving DryVax® that was significantly different from takes. Although the sample size studied was small, we conclude the failure to take in responders correlates with pre-existing immunity of unknown etiology that may attenuate the skin reaction in a way similar to previous smallpox vaccination.
Project description:Transcriptional analysis of global gene expression changes in naïve subjects in response to smallpox vaccination with either DryVax or the replication-competent, attenuated LC16m8 vaccinia virus.
Project description:The purpose of this study is to evaluate the safety of the investigational product GL-ONC1. GL-ONC1, a vaccinia virus, has been genetically modified for use as a potential anti-cancer drug to destroy cancer cells. Vaccinia virus has been used successfully in the past as smallpox vaccine in millions of people worldwide.
Project description:Modified vaccinia Ankara (MVA) immunisation is being deployed to curb the current outbreak of mpox in multiple countries1. Originally authorized for vaccination against smallpox, MVA is a vaccinia virus (VACV) strain that does not replicate in human cells or cause serious adverse events. Here, we conducted a highly multiplexed proteomic analysis2 to quantify >9,000 cellular proteins and ~80% of viral proteins at five time points throughout MVA infection of human cells3. 690 human proteins were down-regulated >2-fold by MVA, revealing a substantial remodelling of the host proteome. >25% of these MVA targets, including multiple components of the nuclear pore complex (NPC), were not shared with VACV-Western Reserve4, which is derived from a first generation smallpox vaccine associated with serious adverse events. Using pharmacological inhibition of viral DNA replication and heat-inactivated virions, we discovered that post-replicative gene expression is necessary for the downregulation of NPC proteins and for elements of MVA antagonism of innate immune sensing. Our approach thus provides the first global view of the impact of MVA infection on the host proteome, offers insights into how MVA interacts with the antiviral defences and identifies cellular mechanisms that may underpin the abortive infection of human cells. These discoveries will prove vital to the rational design of future generations of vaccines.
Project description:Orthopoxviruses are large DNA viruses which can cause disease in numerous host species. Even though the eradication of variola virus - the causative agent of human smallpox M-bM-^@M-^S succeeded, with the end of vaccinations several other orthopoxviruses emerged as potential threat to human health. For instance, animal-borne monkeypox virus, cowpox virus and closely related vaccinia virus are all capable of establishing zoonotic infections in humans. The disease caused by each virus differs in terms of expression and severity, but we still know little about the reasons for these different phenotypes. They may be explained by the unique repertoire of host cell modulating factors encoded by each virus. In this study, we aimed at characterizing the specific modulation of the host cells gene expression profile by orthopoxvirus infection. In our study we analyzed changes in host cell gene expression of HeLa cells after infection with cowpox virus, monkeypox virus or vaccinia virus and compared these to each other and to the gene expression profile of non-infected cells using Agilent Whole Genome Microarray technology. We could identify major differences in viral modulation of host cell immune response genes, especially an induction of genes involved in leukocyte migration and Toll-like receptor signalling in cowpox and monkeypox virus infected cells. This was not observed following vaccinia virus infection. If these differences contribute to the different clinical manifestation of cowpox, monkeypox and vaccinia virus infections in certain host species remains to be elucidated. We analyzed the gene expression profile of HeLa cells wich were either mock-infected or infected with Vaccinia virus strain IHD-W, Cowpox virus strain Brighton Red or Monkeypox virus strain MSF#6 at a multiplicity of infection of 5. Experiments were performed in duplicate. At 6 h post infection total RNA was isolated from infected cells and used for microarray analysis.
Project description:Orthopoxviruses are large DNA viruses which can cause disease in numerous host species. Even though the eradication of variola virus - the causative agent of human smallpox – succeeded, with the end of vaccinations several other orthopoxviruses emerged as potential threat to human health. For instance, animal-borne monkeypox virus, cowpox virus and closely related vaccinia virus are all capable of establishing zoonotic infections in humans. The disease caused by each virus differs in terms of expression and severity, but we still know little about the reasons for these different phenotypes. They may be explained by the unique repertoire of host cell modulating factors encoded by each virus. In this study, we aimed at characterizing the specific modulation of the host cells gene expression profile by orthopoxvirus infection. In our study we analyzed changes in host cell gene expression of HeLa cells after infection with cowpox virus, monkeypox virus or vaccinia virus and compared these to each other and to the gene expression profile of non-infected cells using Agilent Whole Genome Microarray technology. We could identify major differences in viral modulation of host cell immune response genes, especially an induction of genes involved in leukocyte migration and Toll-like receptor signalling in cowpox and monkeypox virus infected cells. This was not observed following vaccinia virus infection. If these differences contribute to the different clinical manifestation of cowpox, monkeypox and vaccinia virus infections in certain host species remains to be elucidated.
Project description:Transcriptional analysis of global gene expression changes in naïve subjects in response to smallpox vaccination with either DryVax or the replication-competent, attenuated LC16m8 vaccinia virus. Subjects were vaccinated with either DryVax or LC16m8 (5 from each group), and blood samples were taken at days 0, 3, 7, 10, 13, and 21 post-vaccination. PBMCs were isolated from the samples, and were then further separated into cell subpopulations using positive selection against CD markers (CD4+, CD20+). There are a total of 142 samples analyzed in this dataset.
Project description:Memory B cells represent one of the pillar of humoral protection and are found in the circulation and secondary lymphoid organs several decades after initial pathogen or vaccine encounter. The exact cellular and biological mechanisms allowing long-term survival of quiescent cells in such a fluctuating microenvironment remain poorly understood. Assessing the true longevity of human memory B cells against common pathogens is, in most settings, hindered by the possibility for any given individual to re-encounter them during his lifetime. Smallpox, officially declared eradicated in 1980 (Fenner WHO 1988), represents one notable exception. Alongside smallpox eradication, anti-smallpox vaccination, based on the live Vaccinia virus, was progressively discontinued during the 1970s. As such, any detectable anti-vaccinia memory B cell in an individual post 2010 would likely have been generated more than 40 years ago, without any re-stimulation with the immunizing antigen during that timeframe. Anti-vaccinia antibodies serum titers remain stable in human for more than 80 years after first vaccination (Amanna NEJM 2007, PMID: 17989383), with several identified immunodominant epitopes including the envelope glycoprotein B5R (Lantto J Virol 2011, PMID: 21147924). Anti-vaccinia memory B cells have similarly been followed longitudinally in the blood for up to 65 years post vaccination (Amanna NEJM 2007, PMID: 17989383 ; Crotty JI 2003, PMID : 14607890) and, following a contraction phase taking place in the first couple of years after immunization, reach a remarkably stable plateau that last for decades at around 0.1% of total circulating IgG+ memory B cells. Functional analysis of such long-lived memory B cells, however, is still lacking. As a proxy to study long-lived memory B cells, IgG+ switched memory B cells specific for the immunodominant Vaccinia antigen B5R (B5R+ IgG+ memory B cells) were sorted and analyzed by scRNAseq from the spleen of six organ donors, collected between 2015 and 2018. For all donors, B5R+ IgG+ memory B cells were sorted alongside total IgG+ memory B cells (live IgD-CD27+IgG+CD20+CD3-CD14-CD16-) and naïve B cells (live IgD+CD27-CD38-CD24-CD20+CD3-CD14-CD16-). Single-cell mRNA sequencing was performed according to an adapted version of the SORT-seq protocol (Muraro et al., 2016, PMID: 27693023), with cDNA libraries generation, sequencing and reads alignment performed at Single Cell Discoveries (Utrecht, Netherlands).