A study carried out by the Institute of Natural Resources and Agrobiology of Salamanca (IRNASA-CSIC) within the framework of the Interdisciplinary Thematic Platform (PTI) Global Health of the CSIC and published in the International Journal of Molecular Science (IJMS) determines that antigens of the helminth Fasciola hepatica present antiviral effects against SARS-CoV-2 that causes COVID-19 in vitro.
Helminths are large parasitic worms that can infect humans, being responsible for the development of diseases in more than two billion people in the world. Given the points of coincidence that many pathogens have when generating an immune response in the host, this group of researchers proposes that helminth infection can influence the response to other concurrent infectious diseases, specifically SARS-CoV-2 infection. with potential to generate new antivirals.
In this study, in which the Institute of Integrative Systems Biology (I2SysBio, CSIC-University of Valencia joint center) also participates, the species Fasciola hepatica is used, a parasitic helminth with a complex life cycle that can infect humans, causing fasciolosis. , caused by ingestion of metacercariae (their larval form) in water or aquatic plants. Ingested larvae excyst in the duodenum and release FhNEJ, and then continue their development to adulthood in the bile ducts, potentially causing tissue damage.
FhNEJs induce changes in host cell proteins related to vesicle-mediated trafficking and positive regulation of the type I interferon (IFN)-mediated immune response. Both responses are directly related to the cellular entry and replication of SARS-CoV-2, so the hypothesis of the study is that F. hepatica infection may have an influence on subsequent infection by the COVID virus.
To evaluate this hypothesis, Vero cells pretreated with tegument-enriched FhNEJ antigen extract (FhNEJ-TEG) ​​were used and a reduction in infection by VSV (vesicular stomatitis virus) particles pseudotyped with the SARS-S protein was observed. CoV-2 (VSV-S2). These results were verified with an in vitro model, using real SARS-CoV-2 infections. It should be noted that the antiviral activity observed in treatment with FhNEJ-TEG is similar to that obtained thanks to treatment with remdesivir, one of the few drugs currently approved to treat COVID-19.
In addition to this, Vero cells were treated after infection with VSV-S2 and a reduction in infection was also observed, suggesting that FhNEJ-TEG may also affect post-entry stages of infection.
Together, these data suggest that the production of FhNEJ-derived molecules could be promoted to be applied as therapeutic agents against SARS-CoV-2 and other emerging respiratory viruses, given their ability to alter their infectivity.
Source: Institute of Natural Resources and Agrobiology of Salamanca (IRNASA-CSIC)
