[Metaphors of immunology: war and peace]

Immunology has always relied on metaphorical language. In its early beginnings, it varied between bellicose images and images that stressed the interaction of immunity mechanisms with the organism's physiological functions overall. In the late nineteenth century, white blood globules were not only compared to 'border police' assigned to rebuffing intruders -- an army formed to combat the invaders -- but were also described as a physiological mechanism for eliminating aged, dead cells, at times exterminators of foreign bodies. Antibodies were described as very powerful, deadly weapons but also as an integral part of mechanisms that allowed cells to assimilate food. This duality of images holds true today. The article analyzes the emergence and development of these images, relating them to the redefinition of immunology as a science of the self and non-self and dissecting them in light of recent events, such as the Aids epidemic.