Reciprocal BEBOV GP serum neutralizing antibody titers at which 50% of rVSV-BEBOV-GP was neutralized.

<p> Succumbed to BEBOV challenge.</p><p>^a rVSV blend; rVSV-SEBOV-GP plus rVSV-ZEBOV-GP, rVSV Prime-boost; rVSV-SEBOV-GP first then rVSV-ZEBOV-GP 14 days after.</p><p>−22; day of boost.^b Days after BEBOV challenge, Day </p><p><a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0002600#pntd-0002600-t001" target="_blank">Table 1</a> for Terminal sample day of animals with a <u>*</u>; all others are from Day 28.^c See </p

IgG antibody response to rVSV-filovirus-GP vaccination.

<p>Reciprocal endpoint dilution titers for IgG against SEBOV GP (A), ZEBOV GP (B), and BEBOV GP (C) were determined from serum samples in each Group at 29, 8, and 0 days before challenge. Group 1 (PBS only control, black), Group 2 (rVSV-BEBOV-GP only, red), Group 3 (rVSV-SEBOV-GP plus rVSV-ZEBOV-GP, green), and Group 4 (rVSV-SEBOV-GP only, then rVSV-ZEBOV-GP 14 days post, yellow/blue). Red **, p<0.01 (Group 2 vs Group 4), Red ***, p<0.001 (Group 2 vs Group 4), Blue **, p<0.01 (Group 3 vs. Group 4), and Blue >, p>0.05 (Group 3 vs Group 4).</p

Clinical findings and viremia for NHPs challenged with BEBOV.

<p> 98C007 expired before sampling at day 10 could be achieved.</p><p>^a rVSV blend; rVSV-SEBOV-GP plus rVSV-ZEBOV-GP, rVSV Prime-boost; rVSV-SEBOV-GP first then rVSV-ZEBOV-GP 14 days after.</p><p>°F over baseline or at least 1.5°F over baseline and ≥103.5°F. Moderate rash refers to petechiae coverage of more than 20% of the skin. Lymphopenia and thrombocytopenia are defined by a ≥35% drop in numbers of lymphocytes and platelets, respectively. (ALP) alkaline phosphatase, (AST) aspartate aminotransferase, (BUN) blood urea nitrogen, (GGT) gamma glutamyltransferase: 2- to 3-fold increase,→; 4- to 5-fold increase, →→; >5 fold increase, →→→.^b Days after BEBOV challenge are in parentheses. Fever is defined as a temperature more than 2.5</p><p>^c No symptoms observed.</p><p>₁₀ PFU/ml<b>/</b>qRT-PCR positive (+) or negative (−). +, ≤5 log₁₀; ++, ≥6 log₁₀; +++, ≥7 log₁₀.^d Days after BEBOV challenge are in parentheses. Viral load for each day is depicted as: log</p

Group outcomes of BEBOV challenge.

<p>(A) Kapplan-Meier survival curve for each Group post BEBOV challenge. (B) Clinical scores for each individual within each Group after BEBOV challenge. Group 1 (PBS only control, black), Group 2 (rVSV-BEBOV-GP only, red), Group 3 (rVSV-SEBOV-GP plus rVSV-ZEBOV-GP, green), and Group 4 (rVSV-SEBOV-GP only, then rVSV-ZEBOV-GP 14 days post, yellow/blue). The x-axis represents clinical scores from Day 0 to Day 14 post challenge for each individual animal to show disease progression.</p

BEBOV cross-protection study design.

<p>(A) Diagram of rVSV genome for each vaccine used in this study. N; nucleoprotein, P; phosphoprotein, M; matrix protein, GP; filovirus glycoprotein (ZEBOV (blue), SEBOV (yellow), or BEBOV (red)), L; large polymerase protein. (B) Depiction of the vaccine groups: Group 1 (PBS only control, black), Group 2 (rVSV-BEBOV-GP only, red), Group 3 (rVSV-SEBOV-GP plus rVSV-ZEBOV-GP, green), and Group 4 (rVSV-SEBOV-GP only, then rVSV-ZEBOV-GP 14 days post, yellow/blue). (C) Flow chart showing the days of vaccination (triangles), days of sampling (arrows), and day of challenge (*). The yellow triangle represents the first vaccination phase of Group 4 where the animals were vaccinated with rVSV-SEBOV-GP, the red and green triangles represent the day Groups 2 (red) and 3 (green) were vaccinated, and the blue triangle represents the day of rVSV-ZEBOV-GP vaccination in Group 4.</p

Durability of a Vesicular Stomatitis Virus-Based Marburg Virus Vaccine in Nonhuman Primates

<div><p>The filoviruses, Marburg virus (MARV) and Ebola virus, causes severe hemorrhagic fever with high mortality in humans and nonhuman primates. A promising filovirus vaccine under development is based on a recombinant vesicular stomatitis virus (rVSV) that expresses individual filovirus glycoproteins (GPs) in place of the VSV glycoprotein (G). These vaccines have shown 100% efficacy against filovirus infection in nonhuman primates when challenge occurs 28–35 days after a single injection immunization. Here, we examined the ability of a rVSV MARV-GP vaccine to provide protection when challenge occurs more than a year after vaccination. Cynomolgus macaques were immunized with rVSV-MARV-GP and challenged with MARV approximately 14 months after vaccination. Immunization resulted in the vaccine cohort of six animals having anti-MARV GP IgG throughout the pre-challenge period. Following MARV challenge none of the vaccinated animals showed any signs of clinical disease or viremia and all were completely protected from MARV infection. Two unvaccinated control animals exhibited signs consistent with MARV infection and both succumbed. Importantly, these data are the first to show 100% protective efficacy against any high dose filovirus challenge beyond 8 weeks after final vaccination. These findings demonstrate the durability of VSV-based filovirus vaccines.</p></div

Survival-associated genes are transcriptionally interconnected.

<p>A network illustrating transcriptional connections between 37 genes which distinguish between “EBOV-infected, Treated Survivors” (ETS), “EBOV-infect, Treated Non-Survivors” (ETNS), and NHPs that did not receive anticoagulant treatment (“EBOV Only”; see <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0003061#s2" target="_blank"><i>Materials and Methods</i></a>). Nodes are labeled with the gene name, edges indicate regulation of expression from transcription factor to target gene; arrows indicate up-regulation, bars indicate down-regulation, circles indicate up- and down-regulation, and unmarked, light grey edges indicate unknown regulation. Nodes are colored according to the difference in mean expression between the ETS and “Non-Survivor” (NS; ETNS and EO) groups; blue indicates lower expression values in the ETS group compared to the NS group, red indicates higher expression values in the ETS group compared to the NS group (scale indicated). Nodes that are colored grey (<i>e.g.</i> p53) are master transcriptional regulators which were not identified as being differentially expressed by our protocol.</p

Representative rVSV-wt histology showing lesions in all neural tissue examined.

<p>(A) Frontal cortex (10×) section with severe encephalitic changes including perivascular lymphohistocytic cuffs (arrows) and aggregates of lymphocytes in the neuroparenchyma (*). (B) Frontal cortex (10×) section with perivascular cuff of lymphocytes and histocytes (arrow). (C) Cerebellum (10×) section with aggregates of lymphocytes in the parenchyma (arrows) admixed with increased numbers of reactive glial cells. (D) Spinal cord (10×) section with gliosis admixed with regions of perivascular inflammation (arrows). (E) Frontal cortex (40×) section depicting large numbers of perivascular lymphocytes and histocytes infiltrating into the adjacent gray matter. (F) Basal ganglia (40×) section depicting large numbers of lymphocytes and histocytes both around a meningeal vessel and invading into the adjacent tissue.</p

Viral loads in neural tissue and LN as measured by qRT-PCR (log10 copies/g)/or virus log10.

@<p>Negative (neg) result below the detection of assay at 4 log10 copies/g of tissue. FC-L = left frontal cortex, OC-L = left occipital cortex, FC-R = right occipital cortex, OC-R = right, occipital cortex, CSC = cervical spinal cord, LN = lymph node; rVSV vaccine inoculation occurred in left hemisphere.</p>*<p>euthanized on day 6;</p>**<p>euthanized on day.</p

Representative rVSV-MARV-GP histology.

<p>(A) Frontal cortex (10×) section from 59-09 that had a small perivascular cuff of lymphocytes. (B) Frontal cortex (10×) section with no lesions. (C) Cerebellum (10×) section with no lesions. (D) Spinal cord (10×) section with no lesions. (E) Frontal cortex (40×) section with a mild perivascular cuff of lymphocytes. (F) Frontal cortex (40×) section with a scant perivascular cuff of lymphocytes.</p