Surveillance of human mitral valve cells by autochthonous lymphocytes, in vitro

Analysis of a time-lapse film of cultured human mitral valve endothelium containing autochthonous lymphocytes reveals details of a pattern of interaction suggesting a previously undescribed type of cellular surveillance. Highly mobile lymphocytes rapidly approach individual endothelial cells, slowly circumnavigate the nuclear region, and rapidly move away to repeat this behavior on adjacent cells during the 1-month culture period.