Iota-carrageenan prevents the replication of SARS-CoV-2 on an in vitro respiratory epithelium model
Varese et al.
, Iota-carrageenan prevents the replication of SARS-CoV-2 on an in vitro respiratory epithelium model
, bioRxiv, doi:10.1101/2021.04.27.441512 (Preprint) (In Vitro)
Varese et al., 27 Apr 2021, preprint, 5 authors.
In Vitro studies are an important part of preclinical research, however results may be very different in vivo.
Abstract: bioRxiv preprint doi: https://doi.org/10.1101/2021.04.27.441512; this version posted April 27, 2021. The copyright holder for this preprint (which
was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made
available under aCC-BY-NC-ND 4.0 International license.
Iota-carrageenan prevents the replication of SARS-CoV-2 on an in
vitro respiratory epithelium model
Augusto Varese1,†, Ana Ceballos1,†, Carlos Palacios2, Juan Manuel Figueroa2, Andrea Vanesa
†These authors have contributed equally to this work.
Instituto de Investigaciones Biomédicas en Retrovirus y SIDA (INBIRS), Universidad de Buenos
Aires, Buenos Aires, Argentina.
Respiratory Research Group, Instituto de Ciencia y Tecnología Dr. César Milstein - (Consejo
Nacional de Investigaciones Científicas y Técnicas CONICET- Fundación Pablo Cassará), Saladillo
2468, Ciudad de Buenos Aires, C1440FFX, Argentina.
Andrea Vanesa Dugour
Keywords: SARS-CoV-21, COVID-192, iota-carrageenan3, respiratory epithelium4, antivirals5.
There are, except for remdesivir, no approved antivirals for the treatment or prevention of SARSCoV-2 infections. Iota-carrageenan formulated into a nasal spray has already been proven safe and
effective in viral respiratory infections. We explored this antiviral activity in Calu-3, a human
respiratory model cell line. A formula of iota-carrageenan and sodium chloride, as a nasal spray,
already approved for human use, effectively inhibited SARS-CoV-2 infection in vitro, providing a
more substantial reference for further clinical studies or developments.
The severe acute respiratory coronavirus 2 (SARS-CoV-2) is responsible for the currently ongoing
pandemic coronavirus disease (COVID-19), counting more than 144.878.978 confirmed cases and
more than 3.075.042 deaths worldwide by April 23, 2021 (Dong et al., 2020). There are still no
adequate therapeutic or preventive medicines for COVID-19; repurposing established medications
with recognized safety profiles is a possible approach for preventing or treating the disease and
shortening the time-consuming drug development stages.
During the first days of the infection, the virus replicates mainly in the nasal cavity and the
nasopharynx; therefore, nasal sprays with antiviral activity would reduce the viral load in these
Marine-derived polysaccharides, such as carrageenans, are a family of linear sulfated polysaccharides
extracted from red seaweeds, widely used as thickening agents and stabilizers for food. Besides these
properties, the iota-carrageenan demonstrated antiviral activity against several viruses, including
respiratory viruses such as human rhinovirus, influenza A H1N1, and common cold coronavirus
(Grassauer et al., 2008; Leibbrandt et al., 2010; Morokutti-Kurz et al., 2015). Iota-carrageenan
inhibits virus infection mainly based on its interaction with the surface of viral particles, preventing
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