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

New study results show that previously infected patients had molecular markers that suggested that immune cells could last longer and migrate more effectively to the respiratory tract.

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