COVID-19 Vaccines Generate T Cells to Protect Against Multiple Variants

Both the Moderna and Pfizer COVID-19 vaccines generate long-term populations of T cells that can protect against multiple variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), results of a new study by Gladstone Institutes show.

Overall, our data support the idea that vaccines are eliciting a very robust T cell response in healthy individuals,” Nadia Roan, PhD, associate investigator at Gladstone, said in a statement. “But they also suggest there may be some ways to improve them further, by getting more of the vaccine-elicited T cells to park themselves in the respiratory tract.”

Investigators found that fully vaccinated individuals had T cells that responded to 3 different variants of SARS-CoV-2. However, the Delta variant was not included in the study.

T cells respond to already infected cells and typically last longer after initial infection or vaccine to prevent severe symptoms.

Investigators found that individuals who were previously infected with COVID-19 had molecular markers that suggested that immune cells could last longer and migrate more effectively to the respiratory tract.

They also found that more effective T cell defense in respiratory tract may help explain why breakthrough infections are less frequent for individuals with prior COVID-19 infections than those who were just vaccinated.

Other studies are being planned to investigate how T cells behave in cases of long COVID-19individual T cell responses after COVID-19 vaccinations in immunocompromised individuals, and T cell responses after booster vaccines.

The study results were published in the scientific journal eLife.

Reference

Immune response to COVID-19 vaccine different with prior infection. EurekAlert. News release. October 12, 2021. Accessed on October 13, 2021. https://www.eurekalert.org/news-releases/931316