T-Cells May Protect Vulnerable Patients From COVID-19

T-cells taken from the blood of patients who recovered from coronavirus disease 2019 (COVID-19) can help protect other vulnerable patients from infection, according to a study published in Blood.

The COVID-19 pandemic has caused over 1.1 million deaths and there have been more than 42.7 million confirmed cases worldwide, according to the World Health Organization. Among individuals who recover from the virus, T-cells give them immunity from reinfection because those cells are now primed to fight it, according to the study authors. Understanding how these T-cells work can potentially help in the development of a COVID-19 vaccine.

Investigators examined previous phase 1 clinical trials that use virus-targeting T-cells “trained” to target viruses, such as Epstein-Barr virus, to hypothesize that the same could be true for COVID-19 T-cells, according to the study. The study authors predict that T-cells could be infused into immunocompromised patients in order to help them build immunity to the virus.

The T-cells identified in the study are predominantly grown from the peripheral blood of donors who were seropositive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). According to the study, SARS-CoV-2-directed T-cells have adapted to predominantly target specific parts of the viral protein found in the cell membrane.

According to the investigators, this completely reveals new ways that the immune system responds to COVID-19 infection.

"We found that many people who recover from COVID-19 have T-cells that recognize and target viral proteins of SARS-CoV-2, giving them immunity from the virus because those T-cells are primed to fight it," said study leader Michael Keller, MD, a pediatric immunology specialist at Children's National Hospital, in the press release. "This suggests that adoptive immunotherapy using convalescent T-cells to target these regions of the virus may be an effective way to protect vulnerable people, especially those with compromised immune systems due to cancer therapy or transplantation."

The study is also relevant to the COVID-19 vaccine, according to the authors. The ability of the T-cells to target the membrane protein may open another option for vaccine developers to consider when determining how to protect against the virus. Additionally, treating vulnerable patients with T-cells may provide a more viable option than the vaccine altogether, as underlying conditions may make the vaccine unsafe or ineffective for this group.

Reference:

T-Cells from recovered COVID-19 patients show promise to protect vulnerable patients from infection [news release] October 26, 2020; Washington, DC. https://www.eurekalert.org/pub_releases/2020-10/cnh-tfr102620.php. Accessed October 26, 2020.