Ebola Therapeutic Study and Future Directions.

The constant Ebola epidemic outbreaks in Africa arisen in waves of panic worldwide. There is a high mortality rate (30-70%) among the Ebola-infected people in virus- stricken areas. Despite these horrors, the medical capabilities against this deadly viral disease were provided by limited therapeutic agents/options. As a result, several patented agents, biotherapies or prophylactic/therapeutic vaccines need to be reviving into the global markets-including patents of small molecular chemicals, short sequences or oligomers of DNA/RNA, linkages of chemicals with bio-molecules, herbal medicine and so on. In addition, the possible mechanisms of action of these therapeutic options are underway. To promote Ebola biomedical study, the multiple characters of Ebola infections-its origin, pathologic progress, genomic changes, therapeutic context and economic considerations are outlined in this review. Finally, a great difference can be expected after these types of efforts.

Intranasal vaccination with ebola virus GP amino acids 258-601 protects mice against lethal challenge.

Ebola virus (EBOV) disease (EVD) leads to lethal hemorrhagic fever with a case fatality rate as high as 90%, thus posing a serious global public health concern. However, while several vaccines based on the EBOV glycoprotein have been confirmed to be effective in animal experiments, no licensed vaccines or effective treatments have been approved since the first outbreak was reported in 1976. In this study, we prepared the extracellular domain of the EBOV GP protein (designated as N20) by prokaryotic expression and purification via chromatography. Using CTA1-DD (designated as H45) as a mucosal adjuvant, we evaluated the immunogenicity of N20 by intranasal administration and the associated protective efficacy against mouse-adapted EBOV challenge in mice. We found that intranasal vaccination with H45-adjuvanted N20 could stimulate humoral immunity, as supported by GP-specific IgG titers; Th1 cellular immunity, based on IgG subclasses and IFN-γ/IL-4 secreting cells; and mucosal immunity, based on the presence of anti-EBOV IgA in vaginal lavages. We also confirmed that the vaccine could completely protect mice against a lethal mouse-adapted EBOV (MA-EBOV) challenge with few side effects (based on weight loss). In comparison, mice that received N20 or H45 alone succumbed to lethal MA-EBOV challenge. Therefore, mucosal vaccination with H45-adjuvanted N20 represents a potential vaccine candidate for the prevention of EBOV in an effective, safe, and convenient manner.

From bench to almost bedside: the long road to a licensed Ebola virus vaccine.

INTRODUCTION: The Ebola virus (EBOV) disease epidemic during 2014-16 in West Africa has accelerated the clinical development of several vaccine candidates that have demonstrated efficacy in the gold standard nonhuman primate (NHP) model, namely cynomolgus macaques. AREAS COVERED: This review discusses the pre-clinical research and if available, clinical evaluation of the currently available EBOV vaccine candidates, while emphasizing the translatability of pre-clinical data generated in the NHP model to clinical data in humans. EXPERT OPINION: Despite the existence of many successful EBOV vaccine candidates in the pre-clinical stages, only two platforms became the focus of Phase 2/3 efficacy trials in Liberia, Sierra Leone, and Guinea near the peak of the epidemic: the Vesicular stomatitis virus (VSV)-vectored vaccine and the chimpanzee adenovirus type 3 (ChAd3)-vectored vaccine. The results of three distinct clinical trials involving these candidates may soon pave the way for a licensed, safe and efficacious EBOV vaccine to help combat future epidemics.

Sasang Medical Perspectives on Viral Immunity: A Discussion of Intrinsic, Constitutionally Related Factors in Disease Onset and Resistance.

There remain more questions than answers regarding the manifestation of certain diseases, such as Ebola, in some otherwise healthy individuals but not in others. Sasang medicine offers a possible clue to solving this mystery by introducing a constitutionally based, intrinsic approach to determining disease susceptibility. The Sasang constitution is identified by a detailed examination of inherent physiological and psychological traits that are likely, but not yet, to be associated with specific genetic patterns. Hence, it is anticipated that after further examination, the Sasang model will contribute to the advancement of medical research and treatment by establishing genetically traceable psychological and physiological traits that contribute to, or offer protection against, various diseases. To progress along this journey, additional research involving Sasang-based organ-associated emotions and inherent emotional/physiological inclinations is warranted. This study presents an argument in favor of additionally examining constitutionally specific disease components related to viral epidemiology.

Preclinical Development of Inactivated Rabies Virus-Based Polyvalent Vaccine Against Rabies and Filoviruses.

We previously described the generation of a novel Ebola virus (EBOV) vaccine based on inactivated rabies virus (RABV) containing EBOV glycoprotein (GP) incorporated in the RABV virion. Our results demonstrated safety, immunogenicity, and protective efficacy in mice and nonhuman primates (NHPs). Protection against viral challenge depended largely on the quality of the humoral immune response against EBOV GP.Here we present the extension and improvement of this vaccine by increasing the amount of GP incorporation into virions via GP codon-optimization as well as the addition of Sudan virus (SUDV) and Marburg virus (MARV) GP containing virions. Immunogenicity studies in mice indicate similar immune responses for both SUDV GP and MARV GP compared to EBOV GP. Immunizing mice with multiple antigens resulted in immune responses similar to immunization with a single antigen. Moreover, immunization of NHP with the new inactivated RABV EBOV vaccine resulted in high titer neutralizing antibody levels and 100% protection against lethal EBOV challenge when applied with adjuvant.Our results indicate that an inactivated polyvalent vaccine against RABV filoviruses is achievable. Finally, the novel vaccines are produced on approved VERO cells and a clinical grade RABV/EBOV vaccine for human trials has been produced.

A DNA vaccine for the prevention of Ebola virus infection.

The NIH and Vical Inc are developing an intramuscular needle-free DNA vaccine containing plasmids encoding the envelope glycoprotein of Ebola virus (EBOV) from the Sudan and Zaire strains, and the nucleoprotein of EBOV Zaire strain. A phase I clinical trial demonstrated a good safety profile, with most adverse events limited to the site of injection and largely attributable to the delivery.

Progress towards the treatment of Ebola haemorrhagic fever.

Being highly pathogenic for human and nonhuman primates and the subject of former weapon programmes makes Ebola virus one of the most feared pathogens worldwide today. Due to a lack of licensed pre- and postexposure intervention, the current response depends on rapid diagnostics, proper isolation procedures and supportive care of case patients. Consequently, the development of more specific countermeasures is of high priority for the preparedness of many nations. Over the past years, enhanced research efforts directed to better understand virus replication and pathogenesis have identified potential new targets for intervention strategies. The authors discuss the most promising therapeutic approaches for Ebola haemorrhagic fever as judged by their efficacy in animal models. The current development in this field encourages discussions on how to move some of the experimental approaches towards clinical application.