Did you know that the innate immune DNA sensor TLR9 is on the membrane of red blood cells? I didn’t know that. To learn about why it’s there, listen to Immune episode #50. In that episode we review evidence that toll-like receptor 9 on the surface of red blood cells binds DNA, leading to uptake by macrophages and innate immune activation.
Immunologist Shane Crotty joins TWiV to discuss the antibody and T cell responses to infection with SARS-CoV-2, followed by answers to listener questions.
Cindy, Steph, and Vincent reveal that lymphocyte trafficking through lymph nodes and lymph is circadian – it is dependent on the time of day.
Become aÂ patronÂ ofÂ Immune!
Show notes at microbe.tv/immune
When you are infected with a microbe, pieces of the pathogen are picked up by sentinel dendritic cells and brought to local lymph nodes. There the sentinels present their gifts to lymphocytes – B (pictured; image credit) and T cells – who then decide if they are foreign, in which case an immune response begins. These lymphocytes circulate throughout the body not continuously, but in a circadian manner – a 24 hour cycle.