This study evaluated a depot-formulated cytokine-based adjuvant to improve the efficacy of the recombinant F1V (rF1V) plague vaccine and examined the protective response following aerosol challenge in a murine model. The results of this study showed that co-formulation of the Alhydrogel-adsorbed rF1V plague fusion vaccine with the depot-formulated cytokines recombinant human interleukin 2 (rhuIL-2) and/or recombinant murine granulocyte macrophage colony-stimulating factor (rmGM-CSF) significantly enhances immunogenicity and significant protection at lower antigen doses against a lethal aerosol challenge. These results provide additional support for the co-application of the depot-formulated IL-2 and/or GM-CSF cytokines to enhance vaccine efficacy.

Venezuelan equine encephalitis virus (VEEV) is a disease typically confined to South and Central America, whereby human disease is characterised by a transient systemic infection and occasionally severe encephalitis, which is associated with lethality. Using an established mouse model of VEEV infection, the encephalitic aspects of the disease were analysed to identify biomarkers associated with inflammation. Sequential sampling of lethally challenged mice (infected subcutaneously) confirmed a rapid onset systemic infection with subsequent spread to the brain within 24 h of the challenge. Changes in inflammatory biomarkers (TNF-α, CCL-2, and CCL-5) and CD45+ cell counts were found to correlate strongly to pathology (R>0.9) and present previously unproven biomarkers for disease severity in the model, more so than viral titre. The greatest level of pathology was observed within the olfactory bulb and midbrain/thalamus. The virus was distributed throughout the brain/encephalon, often in areas not associated with pathology. The principal component analysis identified five principal factors across two independent experiments, with the first two describing almost half of the data: (1) confirmation of a systemic Th1-biased inflammatory response to VEEV infection, and (2) a clear correlation between specific inflammation of the brain and clinical signs of disease. Targeting strongly associated biomarkers of deleterious inflammation may ameliorate or even eliminate the encephalitic syndrome of this disease.

Mice were immunized with a combination of self-amplifying (sa) RNA constructs for the F1 and V antigens of Yersinia pestis at a dose level of 1 μg or 5 μg or with the respective protein sub-units as a reference vaccine. The immunization of outbred OF1 mice on day 0 and day 28 with the lowest dose used (1 μg) of each of the saRNA constructs in lipid nanoparticles protected 5/7 mice against subsequent sub-cutaneous challenge on day 56 with 180 cfu (2.8 MLD) of a 2021 clinical isolate of Y. pestis termed 10-21/S whilst 5/7 mice were protected against 1800cfu (28MLD) of the same bacteria on day 56. By comparison, only 1/8 or 1/7 negative control mice immunized with 10 μg of irrelevant haemagglutin RNA in lipid nanoparticles (LNP) survived the challenge with 2.8 MLD or 28 MLD Y. pestis 10-21/S, respectively. BALB/c mice were also immunized with the same saRNA constructs and responded with the secretion of specific IgG to F1 and V, neutralizing antibodies for the V antigen and developed a recall response to both F1 and V. These data represent the first report of an RNA vaccine approach using self-amplifying technology and encoding both of the essential virulence antigens, providing efficacy against Y. pestis . This saRNA vaccine for plague has the potential for further development, particularly since its amplifying nature can induce immunity with less boosting. It is also amenable to rapid manufacture with simpler downstream processing than protein sub-units, enabling rapid deployment and surge manufacture during disease outbreaks.

A transduced mouse model of SARS-CoV-2 infection was established using Balb/c mice. This was achieved through the adenovirus-vectored delivery of the hACE2 gene, to render the mice transiently susceptible to the virus. The model was characterised in terms of the dissemination of hACE2 receptor expression, the dissemination of three SARS-CoV-2 virus variants in vivo up to 10 days following challenge, the resulting histopathology and the clinical signs induced in the mice. In transduced mice, the infection was short-term, with a rapid loss in body weight starting at day 2 with maximum weight loss at day 4, followed by subsequent recovery until day 10. The induced expression of the hACE2 receptor was evident in the lungs, but, upon challenge, the SARS-CoV-2 virus disseminated beyond the lungs to spleen, liver and kidney, peaking at day 2 post infection. However, by day 10 post infection, the virus was undetectable. The lung histopathology was characterised by bronchial and alveolar inflammation, which was still present at day 10 post infection. Transduced mice had differential responses to viral variants ranking CVR-Glasgow 1 > Victoria-1 > England-2 isolates in terms of body weight loss. The transduced mouse model provides a consistent and manipulatable model of SARS-CoV-2 infection to screen viral variants for their relative virulence and possible interventions.

The causative agent of anthrax, Bacillus anthracis, evades the host immune response and establishes infection through the production of binary exotoxins composed of Protective Antigen (PA) and one of two subunits, lethal factor (LF) or edema factor (EF). The majority of vaccination strategies have focused upon the antibody response to the PA subunit. We have used a panel of humanised HLA class II transgenic mouse strains to define HLA-DR-restricted and HLA-DQ-restricted CD4+ T cell responses to the immunodominant epitopes of PA. This was correlated with the binding affinities of epitopes to HLA class II molecules, as well as the responses of two human cohorts: individuals vaccinated with the Anthrax Vaccine Precipitated (AVP) vaccine (which contains PA and trace amounts of LF), and patients recovering from cutaneous anthrax infections. The infected and vaccinated cohorts expressing different HLA types were found to make CD4+ T cell responses to multiple and diverse epitopes of PA. The effects of HLA polymorphism were explored using transgenic mouse lines, which demonstrated differential susceptibility, indicating that HLA-DR1 and HLA-DQ8 alleles conferred protective immunity relative to HLA-DR15, HLA-DR4 and HLA-DQ6. The HLA transgenics enabled a reductionist approach, allowing us to better define CD4+ T cell epitopes. Appreciating the effects of HLA polymorphism on the variability of responses to natural infection and vaccination is vital in planning protective strategies against anthrax.

We undertook a Phase 4 clinical trial to assess the effect of time interval between booster doses on serological responses to AVP. The primary objective was to evaluate responses to a single booster dose in two groups of healthy adults who had previously received a complete 4-dose primary course. Group A had received doses on schedule while Group B had not had one for ≥2 years. Secondary objectives were to evaluate the safety and tolerability of AVP booster doses, and to gain information on correlates of protection to aid future anthrax vaccine development. Blood samples were taken on Day 1 before dosing, and on Days 8, 15, 29 and 120, to measure Toxin Neutralisation Assay (TNA) NF50 values and concentrations of IgG antibodies against Protective Antigen (PA), Lethal Factor (LF) and Edema Factor (EF) by ELISA.For each serological parameter, fold changes from baseline following the trial AVP dose were greater in Group B than Group A at every time-point studied. Peak responses correlated positively with time since last AVP dose (highest values being observed after intervals of ≥10 years), and negatively with number of previous doses (highest values occurring in individuals who had received a primary course only). In 2017, having reviewed these results, the Joint Committee on Vaccination and Immunisation (JCVI) updated UK anthrax vaccination guidelines, extending the interval between routine AVP boosters from one to 10 years.Booster doses of AVP induce significant IgG responses against the three anthrax toxin components, particularly PA and LF. Similarly high responses were observed in TNA, a recognised surrogate for anthrax vaccine efficacy. Analysis of the 596 TNA results showed that anti-PA and anti-LF IgG make substantial independent contributions to neutralisation of anthrax lethal toxin. AVP may therefore have advantages over anthrax vaccines that depend on generating immunity to PA alone.

The development of a safe and effective vaccine against Yersinia pestis, the causative organism for plague disease, remains an important global health priority. Studies have demonstrated effective immune-based protection against plague challenge that is induced by plague antigen subunit vaccination in an aqueous alhydrogel formulation; however, whether these candidate vaccines in this formulation and presentation, induce long-lasting immunological memory in the form of durable cellular and antibody recall responses has not been fully demonstrated. In this study, we analyzed germinal center T follicular helper and germinal center B cell responses following F1V and F1 + V plague subunit immunization of mice with vaccines formulated in various adjuvants. Our data demonstrate that recombinant plague protein immunization formulated with IL-2/GM-CSF cytokines bound to alhydrogel adjuvant drive an increase in the magnitude of the germinal center T follicular helper and germinal center B cell responses following primary immunization, compared to vaccines formulated with Alhydrogel adjuvant alone. In contrast, plague protein subunit immunization combined with CpG ODN bound to alhydrogel increased the magnitude and duration of the germinal center Tfh and B cell responses following booster immunization. Importantly, enhanced germinal center Tfh and B cell responses correlated with long-lasting and high F1V-specific antibody titers and more robust antibody recall responses to F1V re-exposure. These findings indicate that vaccine formulations that drive enhancement of the germinal center Tfh and B cell responses are critical for inducing durable plague-specific humoral immunity.

Two monoclonal antibodies directed to the V antigen of Yersinia pestis have been tested for protective efficacy in a murine model of bubonic plague. Mice were infected with a current clinical isolate from Madagascar, designated Y. pestis 10-21/S. Mab7.3, delivered to mice intra-periteoneally at either 24 h prior to, or 24 h post-infection, was fully protective, building on many studies which have demonstrated the protective efficacy of this Mab against a number of different clinical isolates of Y. pestis. Mab 29.3, delivered intra-peritoneally at either -24 h or +24 h, protected 4/5 mice in either condition; this has demonstrated the protective efficacy of this Mab in vivo for the first time. These results add to the cumulative data about Mab7.3, which is currently being humanized and highlight its potential as a human immunotherapeutic for plague, which is an enduring endemic disease in Madagascar and other regions of Africa, Asia, and South America.

The field of brain drug delivery faces many challenges that hinder development and testing of novel therapies for clinically important central nervous system disorders. Chief among them is how to deliver large biologics across the highly restrictive blood-brain barrier. Non-ionic surfactant vesicles (NISV) have long been used as a drug delivery platform for cutaneous applications and have benefits over comparable liposomes in terms of greater stability, lower cost and suitability for large scale production. Here we describe a glucosamine-coated NISV, for blood-brain barrier GLUT1 targeting, capable of traversing the barrier and delivering active antibody to cells within the brain. In vitro, we show glucosamine vesicle transcytosis across the blood-brain barrier with intact cargo, which is partially dynamin-dependent, but is clathrin-independent and does not associate with sorting endosome marker EEA1. Uptake of vesicles into astrocytes follows a more classical pathway involving dynamin, clathrin, sorting endosomes and Golgi trafficking where the cargo is released intracellularly. In vivo, glucosamine-coated vesicles are superior to uncoated or transferrin-coated vesicles for delivering cargo to the mouse brain. Finally, mice infected with Venezuelan equine encephalitis virus (VEEV) were successfully treated with anti-VEEV monoclonal antibody Hu1A3B-7 delivered in glucosamine-coated vesicles and had improved survival and reduced brain tissue virus levels. An additional benefit was that the treatment also reduced viral load in peripheral tissues. The data generated highlights the huge potential of glucosamine-decorated NISV as a drug delivery platform with wider potential applications.

As the ongoing outbreak in the Democratic Republic of Congo illustrates, Ebola virus disease continues to pose a significant risk to humankind and this necessitates the continued development of therapeutic options. One option that warrants evaluation is that of defective genomes; these can potentially parasitize resources from the wild-type virus and may even be packaged for repeated co-infection cycles. Deletion and copy-back defective genomes have been identified and reported in the literature. As a crude, mixed preparation these were found to have limiting effects on cytopathology. Here we have used synthetic virology to clone and manufacture two deletion defective genomes. These genomes were tested with Ebola virus using in vitro cell culture and shown to inhibit viral replication; however, and against expectations, the defective genomes were not released in biologically significant numbers. We propose that EBOV might have yet unknown mechanisms to prevent parasitisation by defective interfering particles beyond the known mechanism that prevents sequential infection of the same cell. Understanding this mechanism would be necessary in any development of a defective interfering particle-based therapy.

Burkholderia pseudomallei is a Gram-negative bacterium that causes melioidosis, an infectious disease endemic to south-east Asia. As B. pseudomallei is antibiotic-resistant, the need for cell-based vaccines and therapies is crucial to managing melioidosis. Dendritic cells (DC) provide the first line of defense to infection and direct downstream immune responses. Using practical volumes of fresh healthy donor blood, we show that heat-killed B. pseudomallei activated and stimulated expression of pro-inflammatory cytokines TNF-α, IL-1β and IL-6 from both myeloid and plasmacytoid DC. Furthermore, B. pseudomallei- pulsed DC induced activation and proliferation of CD4+ T-cells. Thus, both DC subsets are important for driving primary T helper cell responses to B. pseudomallei in healthy individuals and have the potential to be targeted for future therapies and vaccines.Author Summary Melioidosis is an infectious disease endemic to south-east Asia and northern Australia caused by the bacterium Burkholderia pseudomallei . Melioidosis presents a significant public health threat because it has no effective vaccine or cure, leading to a high mortality rate of between 10-50%. We highlight the possibility of immune-based strategies targeting Burkholderia pseudomallei to better treat and prevent melioidosis. Specifically, we show that dendritic cells-the sentinel cells of the immune system-respond to B. pseudomallei in healthy individuals and in turn can orchestrate downstream protective immune responses. Thus, dendritic cells may be key players in the development of both vaccines and therapeutics for melioidosis as well as other bacteria-driven diseases.

Murine antisera with neutralising activity for the coronavirus causative of Middle East respiratory syndrome (MERS) were induced by immunisation of Balb/c mice with the receptor binding domain (RBD) of the viral Spike protein. The murine antisera induced were fully-neutralising in vitro for two separate clinical strains of the MERS coronavirus (MERS-CoV). To test the neutralising capacity of these antisera in vivo, susceptibility to MERS-CoV was induced in naive recipient Balb/c mice by the administration of an adenovirus vector expressing the human DPP4 receptor (Ad5-hDPP4) for MERS-CoV, prior to the passive transfer of the RBD-specific murine antisera to the transduced mice. Subsequent challenge of the recipient transduced mice by the intra-nasal route with a clinical isolate of the MERS-CoV resulted in a significantly reduced viral load in their lungs, compared with transduced mice receiving a negative control antibody. The murine antisera used were derived from mice which had been primed sub-cutaneously with a recombinant fusion of RBD with a human IgG Fc tag (RBD-Fc), adsorbed to calcium phosphate microcrystals and then boosted by the oral route with the same fusion protein in reverse micelles. The data gained indicate that this dual-route vaccination with novel formulations of the RBD-Fc, induced systemic and mucosal anti-viral immunity with demonstrated in vitro and in vivo neutralisation capacity for clinical strains of MERS-CoV.

Burkholderia pseudomallei is a Gram-negative intracellular bacterium which is recalcitrant to antibiotic therapy. There also is currently no licensed vaccine for this potentially fatal pathogen, further highlighting the requirement for better therapeutics to treat the disease melioidosis. Here we use an oral delivery platform, the bilosome to entrap already-licensed antibiotics. Bilosome-entrapped antibiotics were used to treat mice infected via the aerosol route with B. pseudomallei. When treatment was started by the oral route at 6 h post-infection and continued for 7 days, bilosome levofloxacin and bilosome doxycycline formulations were significantly more efficacious than free antibiotics in terms of survival rates. Additionally, bilosome formulated levofloxacin protected mice from antibiotic and infection induced weight loss following B. pseudomallei infection. The microbiomes of mice treated with levofloxacin were depleted of all phyla with the exception of Firmicutes, but doxycycline treatment had minimal effect on the microbiome. Encapsulation of either drug in bilosomes had no deleterious or clear advantageous effect on microbiome. This indicates that the ability of bilosomes to ameliorate antibiotic induced weight loss is not due to microbiome effects. The bilosome platform not only has potential to reduce adverse effects of orally delivered antimicrobials, but has potential for other therapeutics which may cause detrimental side-effects or require enhanced delivery.

The causative agent of anthrax, Bacillus anthracis , evades the host immune response and establishes infection through the production of binary exotoxins composed of Protective Antigen (PA) and one of two subunits, lethal factor (LF) or edema factor (EF). The majority of vaccination strategies have focused upon the antibody response to the PA subunit. We have used a panel of humanised HLA class II transgenic mouse strains to define HLA-DR-restricted and HLA-DQ-restricted CD4+ T cell responses to the immunodominant epitopes of PA. This was correlated with the binding affinities of epitopes to HLA class II molecules, as well as the responses of two human cohorts: individuals vaccinated with the Anthrax Vaccine Precipitated (AVP) vaccine (which contains PA and trace amounts of LF), and patients recovering from cutaneous anthrax infections. The infected and vaccinated cohorts expressing different HLA types were found to make CD4+ T cell responses to multiple and diverse epitopes of PA. The effects of HLA polymorphism were explored using transgenic mouse lines, which demonstrated differential susceptibility, indicating that HLA-DR1 and HLA-DQ8 alleles conferred protective immunity relative to HLA-DR15, HLA-DR4 and HLA-DQ6. The HLA transgenics enabled a reductionist approach, allowing us to better define CD4+ T cell epitopes. Appreciating the effects of HLA polymorphism on the variability of responses to natural infection and vaccination will be vital in planning protective strategies against anthrax.Author Summary The bacterium responsible for causing the disease anthrax, Bacillus anthracis, produces a binary toxin composed of Protective Antigen (PA) and either Lethal Factor (LF) or Edema Factor (EF). Previous vaccination strategies have focused upon the antibody response to the PA subunit. However, within the field of bacterial immunity, there is a growing appreciation of the importance of the adaptive immune response, specifically led by CD4+ T cells. We identified long-term CD4+ T cell responses to PA epitopes following cutaneous human anthrax infection and vaccination, indicating that this toxin component is a principle B. anthracis antigen. To characterise the impact of polymorphism in HLA class II alleles at DR and DQ loci, we used transgenic mice to map the immunodominant epitopes from PA. This was correlated with survival in the transgenic lines following live anthrax challenge. We were able to demonstrate the differential impact of HLA class II alleles upon the CD4+ T cell immunodominant epitopes which shaped the immune hierarchy and therefore susceptibility to anthrax infection.

Highly virulent bacterial pathogens cause acute infections which are exceptionally difficult to treat with conventional antibiotic therapies alone. Understanding the chain of events that are triggered during an infection of a host has the potential to lead to new therapeutic strategies. For the first time, the transcriptomic responses within the lungs of Balb/C mice have been compared during an acute infection with the intracellular pathogens Burkholderia pseudomallei, Francisella tularensis and Yersinia pestis. Temporal changes were determined using RNAseq and a bioinformatics pipeline; expression of protein was also studied from the same sample. Collectively it was found that early transcriptomic responses within the infected host were associated with the (a) slowing down of critical cellular functions, (b) production of circulatory system components, (c) lung tissue integrity, and (d) intracellular regulatory processes. One common molecule was identified, Errfi1 (ErbB receptor feedback inhibitor 1); upregulated in response to all three pathogens and a potential novel marker of acute infection. Based upon the pro-inflammatory responses observed, we sought to synchronise each infection and report that 24 h p.i. of B. pseudomallei infection closely aligned with 48 h p.i. of infection with F. tularensis and Y. pestis. Post-transcriptional modulation of RANTES expression occurred across all pathogens, suggesting that these infections directly or indirectly modulate cell trafficking through chemokine expression/detection. Collectively, this unbiased NGS approach has provided an in-depth characterisation of the host transcriptome following infection with these highly virulent pathogens ultimately aiding in the development of host-directed therapies as adjuncts or alternatives to antibiotic treatment.

This chapter reviews the history of plague infection, the current incidence of plague globally and the epidemiology of this disease. From this background, the rationale for the development of candidate vaccines, based on key targets elucidated by the bacterium during the infectious process, is described. Although there currently are no easily available, safe and approved vaccines for this disease, significant progress is being made towards the goal of an approved, effective vaccine and the various efforts underway to achieve this, are described.

Here, we report a dual-route vaccination approach for plague, able to induce a rapid response involving systemic and mucosal immunity, whilst also providing ease of use in those resource-poor settings most vulnerable to disease outbreaks. This novel vaccine (VypVaxDuo) comprises the recombinant F1 and V proteins in free association. VypVaxDuo has been designed for administration via a sub-cutaneous priming dose followed by a single oral booster dose and has been demonstrated to induce early onset immunity 14 days after the primary immunisation; full protective efficacy against live organism challenge was achieved in Balb/c mice exposed to 2 x 10(4) median lethal doses of Yersinia pestis Co92, by the sub-cutaneous route at 25 days after the oral booster immunisation. This dual-route vaccination effectively induced serum IgG and serum and faecal IgA, specific for F1 and V, which constitute two key virulence factors in Y. pestis, and is therefore suitable for further development to prevent bubonic plague and for evaluation in models of pneumonic plague. This is an essential requirement for control of disease outbreaks in areas of the world endemic for plague and is supported further by the observed exceptional stability of the primary vaccine formulation in vialled form under thermostressed conditions (40 degrees C for 29 weeks, and 40 degrees C with 75% relative humidity for 6 weeks), meaning no cold chain for storage or distribution is needed. In clinical use, the injected priming dose would be administered on simple rehydration of the dry powder by means of a dual barrel syringe, with the subsequent single booster dose being provided in an enteric-coated capsule suitable for oral self-administration. (C) 2018 Published by Elsevier Ltd.

Background In 2014, Western Africa experienced an unanticipated explosion of Ebola virus infections. What distinguishes fatal from non-fatal outcomes remains largely unknown, yet is key to optimising personalised treatment strategies. We used transcriptome data for peripheral blood taken from infected and convalescent recovering patients to identify early stage host factors that are associated with acute illness and those that differentiate patient survival from fatality. Results The data demonstrate that individuals who succumbed to the disease show stronger upregulation of interferon signalling and acute phase responses compared to survivors during the acute phase of infection. Particularly notable is the strong upregulation of albumin and fibrinogen genes, which suggest significant liver pathology. Cell subtype prediction using messenger RNA expression patterns indicated that NK-cell populations increase in patients who survive infection. By selecting genes whose expression properties discriminated between fatal cases and survivors, we identify a small panel of responding genes that act as strong predictors of patient outcome, independent of viral load. Conclusions Transcriptomic analysis of the host response to pathogen infection using blood samples taken during an outbreak situation can provide multiple levels of information on both disease state and mechanisms of pathogenesis. Host biomarkers were identified that provide high predictive value under conditions where other predictors, such as viral load, are poor prognostic indicators. The data suggested that rapid analysis of the host response to infection in an outbreak situation can provide valuable information to guide an understanding of disease outcome and mechanisms of disease.

In this study, samples from the 2013-2016 West African Ebola virus outbreak from patients in Guinea with Ebola virus disease (EVD) were analyzed to discover and classify what other pathogens were present. Throat swabs were taken from deceased EVD patients, and peripheral blood samples were analyzed that had been taken from patients when they presented at the treatment center with acute illness. High-throughput RNA sequencing (RNA-seq) and bioinformatics were used to identify the potential microorganisms. This approach confirmed Ebola virus (EBOV) in all samples from patients diagnosed as acute positive for the virus by quantitative reverse transcription-PCR in deployed field laboratories. Nucleic acid mapping to Plasmodium was also used on the patient samples, confirming results obtained with an antigen-based rapid diagnostic test (RDT) conducted in the field laboratories. The data suggested that a high Plasmodium load, as determined by sequence read depth, was associated with mortality and influenced the host response, whereas a lower parasite load did not appear to affect outcome. The identifications of selected bacteria from throat swabs via RNA-seq were confirmed by culture. The data indicated that the potential pathogens identified in the blood samples were associated with translocation from the gut, suggesting the presence of bacteremia, which transcriptome data suggested may induce or aggravate the acute-phase response observed during EVD. Transcripts mapping to different viruses were also identified, including those indicative of lytic infections. The development of high-resolution analysis of samples from patients with EVD will help inform care pathways and the most appropriate general antimicrobial therapy to be used in a resource-poor setting. IMPORTANCE Our results highlight the identification of an array of pathogens in the blood of patients with Ebola virus disease (EVD). This has not been done before, and the data have important implications for the treatment of patients with EVD, particularly considering antibiotic stewardship. We show that EVD patients who were also infected with Plasmodium, particularly at higher loads, had more adverse outcomes than patients with lower levels of Plasmodium. However, the presence of Plasmodium did not influence the innate immune response, and it is likely that the presence of EBOV dominated this response. Several viruses other than EBOV were identified, and bacteria associated with sepsis were also identified. These findings were indicative of bacterial translocation across the gut during the acute phase of EVD.

The Ebola virus (EBOV) variant Makona (which emerged in 2013) was the causative agent of the largest outbreak of Ebola Virus Disease recorded. Differences in virus-host interactions between viral variants have potential consequences for transmission, disease severity and mortality. A detailed profile of the cellular changes induced by the Makona variant compared with other Ebola virus variants was lacking. In this study, A549 cells, a human cell line with a robust innate response, were infected with the Makona variant or with the Ecran variant originating from the 1976 outbreak in Central Africa. The abundance of viral and cellular mRNA transcripts was profiled using RNASeq and differential gene expression analysis performed. Differences in effects of each virus on the expression of interferon-stimulated genes were also investigated in A549 NPro cells where the type 1 interferon response had been attenuated. Cellular transcriptomic changes were compared with those induced by human respiratory syncytial virus (HRSV), a virus with a similar genome organisation and replication strategy to EBOV. Pathway and gene ontology analysis revealed differential expression of functionally important genes; including genes involved in the inflammatory response, cell proliferation, leukocyte extravasation and cholesterol biosynthesis. Whilst there was overlap with HRSV, there was unique commonality to the EBOV variants.