https://www.scientificamerican.com/article/spider-man-immune-response-may-promote-severe-covid-19/

The menagerie of immune cells and proteins that defend the human body have received mounting scrutiny in struggles to ward off COVID-19. A lot of the debate has centered around whether, after recovery, a person carrying protective antibodies can return to the workplace. But attention has also turned to runaway immune reactions provoked by the infection that can lead to respiratory failure.

One relatively obscure accomplice when the defense system goes awry is a “Cinderella” immune cell called a neutrophil. Understudied and overshadowed by virus-fighting T cells and antibody-producing B cells, neutrophils make up more than half of our white blood cells and are often the first to arrive at the scene of infection. They attack invaders in several ways—usually by gobbling the intruders up or rallying other immune cells to the fight. But occasionally, perhaps in a last-ditch defensive effort, neutrophils pull a Spider-Man maneuver: they shoot out sticky webs of DNA and toxic proteins that ensnare pathogens and prevent them from spreading. Because a neutrophil dies when it engages in this process —or shortly thereafter—some researchers consider the webs a cellular version of suicide bombing.