Harnessing anti-viral properties from saliva of COVID-19 survivors to advance drug development

Traditionally, blood has been the most used biofluid for screening in medicine, yet it is becoming clear that saliva may be able to take its place in many biomedical applications. Saliva’s composition includes microbiome, immune system, and emerging pathogen cues, providing precise information about oral and overall health. Additionally, saliva collection is non-invasive and readily available. The more we learn about it the more we’ve come to understand the importance of this biofluid, especially as it relates to the human immune system and infectious diseases.

Marcelo Freire, DDS, PhD, DMSc, an associate professor at JCVI, and his team have recently discovered saliva contains a multitude of diverse immune cell populations that have numerous anti‐viral and anti‐inflammatory functions related to fighting SARS‐CoV‐2, the virus causing COVID-19.

While vaccines are the most effective line of defense against COVID-19 and can provide preventative treatment, the virus’ high transmissibility rates and prevalence of mutated strains will continue to wreak havoc on the global population. Thus, it is critical for the scientific community to continue to develop novel and efficacious mucosal immune‐based therapies that can offer immediate benefit to infected patients and prevent transmission. “By controlling transmission via mucosal therapy, we can prevent this and future pandemics”, he says.

The overall goal of this project is to determine how saliva provides protection against the virus at the molecular level. To help with this effort, Dr. Freire and his lab are investigating the salivary immune and antiviral markers present in COVID-19 patients. To do so, they have collaborated with UCSD to collect saliva and blood samples from healthy individuals, and individuals that have been infected with the SARS‐CoV‐2 virus.

Via proteomic studies, identification and quantification of known and novel markers can help identify COVID-19 disease markers that are present and common in both saliva and blood samples. To further explore functional differences, a longitudinal monitoring analysis is being conducted, including surveying COVID-19 patients from active to coalescent phases.

We know that cells in saliva come into direct contact with the virus, yet there are unknown and protective mechanisms inherent to saliva and oral tissues that need to be further studied. To this end, Dr. Freire and his team will use integrative bioinformatic tools and high‐throughput antiviral neutralization assays to gain insight into each significant marker’s method of actions against SARS‐CoV‐2.

Funding