Bone marrow macrophages (blue), taken from mice, interact with M proteins (red) from Group A Streptococcus, visualized by confocal microscopy. Another electron microscopy image depicting the bacteria (purple) is overlayed.UNIVERSITY OF CALIFORNIA, SAN DIEGO HEALTH See J.A. Valderrama et al., “Group A streptococcal M protein activates the NLRP3 inflammasome,” Nature Microbiology, doi:10.1038/s41564-017-0005-6, 2017.
Image of the Day: Dial M for Murder
M proteins from Streptococcus bacteria selectively kill mouse macrophages and human macrophage-like cells by prompting cell death.

