In Vitro Inhibition of SARS-CoV-2 Infection by Bovine Lactoferrin

Abstract

Since its emergence in late 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been posing a serious threat to public health worldwide as the causative agent of coronavirus disease 2019 . Now distributed in a pandemic pattern, this disease still lacks an effective drug treatment with low toxicity, leading pharmaceutical companies and research labs to work against time to find a candidate molecule to efficiently treat the affected patients. Due to the well-known broad-spectrum antimicrobial activity of the lactoferrin protein, we sought to verify whether its bovine form (bLf) would also be effective in vitro against SARS-CoV-2. Using an antiviral assay based on quantitative reverse transcription-polymerase chain reaction (qRT-PCR), we found that bLf reduced progeny virus yield by up to ~84,6% in African green monkey kidney epithelial cells (Vero E6) and ~68,6% in adenocarcinomic human alveolar basal epithelial cells (A549) at 1 mg/mL, a concentration previously shown to have low cytotoxicity. Therefore, our preliminary data suggest that bLf has the potential to constitute a biochemical approach to fight the new coronavirus pandemic. _______________________________________________________________________________________

Thein vitroantiviral activity of lactoferrin against common human coronaviruses and SARS-CoV-2 is mediated by targeting the heparan sulfate co-receptor

“…New findings and highlights of our study include: 1) BLF and HLF have broad-spectrum antiviral activity against infectious SARS-CoV-2, HCoV-OC43, HCoV-NL63, and HCoV-229E viruses in cell culture. It is noted that in parallel to our study, two preprints in biorxiv independently confirmed the antiviral activity of LF against SARS-CoV-2 [50,51].…”

Cellular and Molecular Immunology Approaches for the Development of Immunotherapies against the New Coronavirus (SARS-CoV-2): Challenges to Near-Future Breakthroughs

“…Similar results were shown for Zika and Chikungunya virus [166]. More recently, lactoferrin has been shown to be able to inhibit about 85% of SARS-CoV-2 infection in Vero cells [167].…”

Therapeutic Effects of Lactoferrin in Ocular Diseases: From Dry Eye Disease to Infections

“…Indeed, it has been reported that lactoferrin takes part in the host immune response against severe acute respiratory syndrome coronavirus (SARS-CoV) invasion by enhancing NK cell activity, stimulating neutrophil aggregation and adhesion and preventing the interaction between the viral particle and its cell receptors, represented by heparan sulfate proteoglycans (HSPGs) [54]. Starting from this evidence, similar mechanisms have been proposed for SARS-CoV-2 (COVID-19) infection, for which lactoferrin has additionally shown the capability of inhibiting in vitro viral replication [55].…”