Researchers from Harvard Medical School and Brigham and Women’s Hospital upgraded VirScan — an antibody-detecting technology — to identify signs of infection from coronaviruses like SARS-CoV-2.
A paper published on Sept. 29 describes a new update enabling VirScan to detect coronaviruses. Harvard Medical School professor Stephen J. Elledge said the upgrade may help scientists better understand the body’s immune response to the disease and ultimately design effective vaccines.
“We basically had this technology that had, in the past, been really useful for analyzing antibody response to viruses,” said Eric Fujimura, co-first author of the paper and a graduate student in the Elledge Lab. “It was a pretty obvious step to try to apply that to the pandemic.”
VirScan technology works by fusing DNA from over 1,000 viral strains that make peptides — short protein segments — with bacteria-infecting viruses called bacteriophages.
Human blood contains antibodies, which are produced by the immune system to fight disease. By detecting which antibodies bind with which bacteriophages, VirScan can identify someone’s entire viral infection history through a drop of blood.
After the RNA genomes of SARS-CoV-2 and other coronaviruses were released, the researchers were able to add them to the existing VirScan library and effectively diagnose the disease.
VirScan offers far more information than existing COVID-19 antibody diagnostics, like an ELISA test, which only checks for the presence of a few antibodies specific to a disease.
“You really just say ‘yes or no’ for those, but you don’t really have the detail that you get through VirScan,” Fujimura said.
In fact, the COVID-19 diagnostic tests produced by VirScan “performed similarly and even a little bit better than ELISAs,” according to Ellen L. Shrock, another co-first author of the paper and a graduate student in the Elledge Lab.
The team also further analyzed and compared antibody responses and prior viral infections in hospitalized and non-hospitalized COVID-19 patients.
“What we found is that the people who go to the hospital make way more antibodies than the people who stay home,” Elledge said.
VirScan might also ultimately help with vaccine development.
“Rapid testing of a vaccine and seeing which types of antibodies result from giving that vaccination could be very useful,” said Rachel Bender Ignacio, an infectious diseases specialist at the University of Washington.
Researchers could put the effective antigens into a vaccine and take out those that are ineffective or even distracting to the body’s immune response.
“If we can find the antibodies that bind these peptides that are reoccurring, we can then study them and say, ‘What kind of antibodies are they? Are they neutral antibodies? Are they neutralizing antibodies? Or are they bad antibodies?’” Elledge said.
“The study team found some really provocative data,” said Joshua A. Hill, an assistant professor at the Fred Hutchinson Cancer Research Center. “This is a great foundation to launch a lot of other targeted studies.”
Correction: October 9, 2020
A previous version of this article incorrectly referred to the DNA genomes of coronaviruses. In fact, they have RNA genomes.
Correction: October 9, 2020
A previous version of this article incorrectly stated that researchers could put effective antibodies into a vaccine. In fact, they could put effective antigens.