Individuals who have contracted the coronavirus have been found to rely on antibodies created during infections from earlier coronaviruses to help fight the disease, according to a new study conducted by Northern Arizona University and the Translational Genomics Research Institute (TGen).

The research, published in the journal Cell Reports Medicine, noted that the coronavirus isn’t humanity’s first run-in with a coronavirus. In fact, before SARS-CoV-2—the virus that causes COVID-19—humans have been confronted with at least six other types of coronaviruses.

“Our results suggest that the COVID-19 virus may awaken an antibody response that existed in humans prior to our current pandemic, meaning that we might already have some degree of pre-existing immunity to this virus,” the study’s senior author John Altin, an assistant professor in TGen’s infectious disease branch, said in a statement.

The researchers added that the study’s data could one day assist in designing new diagnostics, evaluating the healing powers of convalescent plasma, and developing new therapeutic treatments. Moreover, they could help design future vaccines or monoclonal antibody therapies that possess the ability to protect against mutations in the coronavirus virus.

“Our findings highlight sites at which the SARS-CoV-2 response appears to be shaped by previous coronavirus exposures, and which have potential to raise broadly neutralizing antibodies,” Altin said.

“We further demonstrate that these cross-reactive antibodies preferentially bind to endemic coronavirus peptides, suggesting that the response to SARS-CoV-2 at these regions may be constrained by previous coronavirus exposure.”

The findings could eventually help explain the widely varying reactions coronavirus patients have to the virus and the reasons why the disease manifests more severely in older populations versus young people.

“Our findings raise the possibility that the nature of an individual’s antibody response to prior endemic coronavirus infection may impact the course of COVID-19 disease,” the study’s lead author Jason Ladner, an assistant professor in Northern Arizona University’s Pathogen and Microbiome Institute, said in a statement.

For the research, the team tapped into a tool called PepSeq to map in detail antibody responses to all human-infecting coronaviruses. PepSeq is a novel technology that enables the construction of highly diverse pools of peptides (short chains of amino acids) that are bound to DNA tags. When combined with high-throughput sequencing, these PepSeq molecule pools allow for deep interrogation of the antibody response to the studied viruses.

“The data generated using PepSeq allowed for broad characterization of the antibody response in individuals recently infected with SARS-CoV-2 compared with those of individuals exposed only to previous coronaviruses that now are widespread in human populations,” Ladner said.

In addition to SARS-CoV-2, the researchers examined the antibody responses from two other potentially deadly coronaviruses—MERS-CoV and SARS-CoV-1.

Ethen Kim Lieser is a Minneapolis-based Science and Tech Editor who has held posts at Google, The Korea Herald, Lincoln Journal Star, AsianWeek, and Arirang TV. Follow or contact him on LinkedIn.

Image: Reuters.