LJI team wins $500,000 XPRIZE for COVID-19 screening protocol

Saliva-based COVID-19 screen proves fast, cheap and reliable

LA JOLLA—A team of scientists at La Jolla Institute for Immunology (LJI) has won the XPRIZE Rapid COVID Testing competition. The team developed and successfully implemented a fast, inexpensive, saliva-based COVID-19 screen that allowed the Institute’s laboratories to reopen safely in 2020. The team will receive $500,000 in guaranteed winnings and is eligible to receive $1 million total as they take steps to make their screening protocol widely available.

The LJI team was led by Suzanne Alarcon, manager of the LJI Next Generation Sequencing Core. Her team members were Hannah Dose, Arturo Hernandez, Kyle Tanguay and Rosalinda Diaz.

“Winning the XPRIZE is validating to the whole team, who have worked extremely hard throughout this entire process,” says Alarcon.

From left to right:  Arturo Hernandez, Suzie Alarcon, Hannah Dose, Kyle Tanguay and Rosalinda Diaz. Credit: Jenna Hambrick, La Jolla Institute for Immunology

From left to right: Arturo Hernandez, Suzie Alarcon, Hannah Dose, Kyle Tanguay and Rosalinda Diaz. Credit: Jenna Hambrick, La Jolla Institute for Immunology

Alarcon and her team took on the project before any COVID-19 saliva-based tests had been approved. She says the approach was a gamble, but LJI needed a COVID-19 screen that would be easier to administer than a blood test or deep nasal swab. A saliva-based screen was the best option.

Once employees submit their saliva sample, the LJI team screens the saliva for very tiny pieces of SARS-CoV-2 virus. The researchers found that looking for the viral particles, as opposed to looking for other signs of infection (such as antibodies), can allow for early detection.

To accomplish this, Alarcon’s team performs a one-step RT-qPCR assay to detect genetic material from SARS-CoV-2. The basic strategy is the same as the Centers for Disease Control’s early SARS-CoV-2 test, but the LJI team has worked to make it faster, safer and cheaper.

Alarcon and her teammates use heat to inactivate the virus (before they uncap the sample) and a detergent to process the sample, eliminating the expensive and time-consuming need to extract or purify RNA from a raw sample. They then repeat each screen to double-check the accuracy of the result.

Because the reaction to detect the virus is done with only a low volume, the scientists can perform high-throughput screening at a low cost. The whole protocol can be carried out in less than a day and only costs $1.21.

The screening has proven accurate in independently validated clinical testing—and LJI employees have embraced the simple process of submitted saliva samples. Alarcon’s team processes nearly 300 samples each week as part of the Institute’s effort to keep employees safe.

When Alarcon heard about the XPRIZE Rapid COVID Testing competition, she knew the LJI protocol fit the bill.

The LJI team is still deciding what to do with the XPRIZE winnings. They are looking at additional funding opportunities to help make screening widely available for free and get sample collection kits to more people. Overall, Alarcon says the prize will give her team members more resources to take on new scientific projects.

Learn more about LJI’s COVID-19 research