Periodic Reporting for period 3 - IF-EBOla (Control of the Ebola Oubreak by both innovative Ultrasensitive Detection of EBOV and therapy)
Reporting period: 2016-11-01 to 2017-10-31
The concept of the IF-EBOLA was to combine an early passive anti-Ebola immunotherapy prompted by timely EBOV-diagnosis, along with immune response monitoring. We developed different innovative technological tools including methods for the ultrasensitive detection of Zaire Ebola virus (ZEBOV) alongside a passive immunotherapy with polyclonal antibody strategy targeting ZEBOV designed to drastically improve their prognosis. Additionally, accurate monitoring of the efficiency of immune response in EVD survivors was performed to achieve a better assessing survival factors and improve the design novel therapies and vaccine strategies.
IF-EBOLA components of a novel integrated approach tackling EVD:
(i) The IF -EBOLA Fab’ntech’s therapy was based in the development of horse anti-EBOV polyclonal F(ab’)2 using a well-established production method (stated by EMA) of ZEBOV antigen that exhibiting very good pharmacological characteristics, and a high anti-viral potency in vitro and in vivo. The F(ab’)2-treated lethally-challenged animals (mice and guinea pigs with a 8-days life expectancy) reached 100% of survive and 100% rescued dying animals (treated 3 days after their lethal challenge). For preparedness, we have stored 900 liters of high-affinity anti-ZEBOV polyclonal serum ready to potentially treat over 20 000 EVD patients. An NHP model will be tested with the NIH (USA);
(ii) Undoubtedly, EBOV detection must be done at the early EVD phase (low viral load and symptoms), to apply supportive and specific treatments, to isolate patients to improve the epidemic control. Also, it is important to treat potential convalescent transmitters exhibiting residual viral loads. To detect residual viruses, we used an ApoH-coated magnetic-bead sample enrichment preparation to concentrate virus in patient samples and combine it with the FDA-approved USAMRIID real-time PCR method (as tested in Sierra Leone and in Liberia and at the USAMRIID in Frederick, US). We achieved an ApoH-dependent ultrasensitive EBOV detection to reveal the presence of residual EBOV from self-cured convalescents previously acutely infected. Using the same method of ultrasensitive enrichment detect bacteria (potentially involved in sepsis) as few as 1 bacterium/5 mL of whole blood and also generate more NGS reads for accurate metagenomic analysis.
(iii) To characterize the immune response against Ebola is key to assess immune and infectious diversity parameters. To this, state-of-the-art technologies were used such as next generation sequencing, metagenomics and RNA arrays. OIB has developed an extremely potent, new hardware and algorithm (RIGEL) dedicated for its efficient use in the field for rapid sequencing and metagenomic analyses; a new outstanding corrected gene bank with 22-times more data than the traditional Genebank. Revealed a prevalence close to 20% of Lassa virus, alongside of nosocomial bacteria and current local infections such as HIV, Mycobacterium tuberculosis and malaria. In addition, the RIGEL algorithm permitted to detect microbiological profiles associated to either survival or fatal outcomes. Future vaccines and therapeutic strategies depend on virus diversity and targeted viral components, such specific viral epitopes. Thus, deep cell and humoral immune response analyses were done by BGU in a survivor population from Liberia by permitting to determine new critical epitopes associating neutralizing capacity of antibodies and cell responses in survivors.
(iv) We have generated compounds able to inhibit enzymes involved in vascular leakage (a hallmark of EVD) resulting from exacerbated inflammatory processes. We published the in vitro proof-of-concept and now we are preparing an in vivo proof-of-concept in a vascular leakage model.
Due to changes and issues faced by the consortium, the communication and dissemination activities have essentially been done through presentation in international conferences, press releases and 2 peer-reviewed publications. A recently submitted manuscript, on the F(ab’)2 efficacy precedes seven other manuscripts in preparation with data generated by OIB (2), BGU (2), Fabentech (1) and IRD (2) (cf. section 6).
The successes of proof-of-concepts done for each one of the IF-EBOLA actions permitted establishing a rich “preparedness IF-EBOLA toolbox”. These tools and concepts are being promoted through different ongoing European projects (PANDORA-ID-NET (2018-2022) & EPIRISK-EBOV (2019-2021)) “extending” the IF-EBOLA action (the consortium staying very active including other ongoing proposals in the USA) as part of our integrated approach: “A Total One-Health Approach for Restauration Impacts”.