B cells are the weapons factories for our immune system. They produce antibodies, which lock on to a virus’s specific fingerprint, its antigen, marking it out for neutralisation by other immune cells. Here we see spleens from two different mice, where B cells are being ‘briefed’ on what their viral enemy looks like. The B cells (stained red) measure 1/2000 of a centimetre across and gather at hubs in the spleen. Here they are shown the virus’s antigen by specialised cells (stained blue). Only those B cells producing the most accurate antibodies survive this training and reproduce in large numbers (stained green). On the right we see the spleen of a mouse lacking a protein called Dicer, without which the B cells are unable to multiply.
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.