Unsung T cells take over immune response when coronavirus antibodies wane

Antibodies have become a familiar word in the pandemic era, perhaps suggesting they’re the best hope for keeping the deadly coronavirus at bay. But when crucial vaccine data was released this week, the spotlight panned to an unsung immune player: T cells.

AstraZeneca Plc, Pfizer Inc. and partner BioNTech SE, as well as China’s CanSino Biologics Inc. all hailed the presence of these white blood cells in vaccine recipients as a sign their experimental shots show promise.

Thrust into focus by recent studies, T cells are a reminder that the body’s defenses rely on more than one weapon, and that much of the immune response to COVID-19 is still a mystery — especially after researchers revealed that the more-lauded antibodies lack staying power.