The Beginning of the End for Ebola?

Researchers at Albert Einstein College of Medicine and the US Army Medical Research Institute of Infectious Diseases have discovered a potential immunotherapeutic treatment for two of the deadliest Ebola virus strains. The Zaire (EBOV) and Sudan (SUDV) Ebola viruses are highly pathogenic, causing severe hemorrhagic fever, and have both caused large outbreaks, with the former responsible for the 2014 Ebola outbreak in West Africa. Despite their similarities, the glycoprotein (GP) sequences of these two strains are 45% divergent, making them antigenically distinct. Despite the fact that very few antibodies with cross-neutralizing properties exist, the researchers in this study developed novel bispecific antibodies that are crossreactive toward both EBOV and SUDV GP epitopes.

Published online in Scientific Reports, the study highlights that these antibodies could be used in therapeutic antibody cocktails to treat Ebola viruses indiscriminately. A broadly effective immunotherapy could be highly advantageous since there is no way to know which strain could cause the next outbreak. Though other therapies/vaccines are being tested – a vaccine is in clinical trials and a 3-monoclonal-antibody cocktail, ZMapp, is in development – they are EBOV-specific and would not work against the two other highly virulent strains (SUDV and Bundibugyo).

In the current study, the researchers engineered bispecific antibodies and showed that they neutralized both EBOV and SUDV in vitro and provided a high degree of protection for mice exposed to lethal doses of either strain. The antibodies still need to be tested in larger animals and humans to know if they will be effective. If they prove to be so, they could potentially be used to minimize the spread of outbreaks and could also be used to prophylactically protect health workers and family members of affected patients.

Source: Albert Einstein College of Medicine