On the Origin of The Immune System

Abstract

Did the immune system evolve to keep out harmful organisms, or is it like a bouncer at a nightclub, trained to allow the right microbes in and kick the less desirable ones out? In the fifth essay in Science 's series in honor of the Year of Darwin , John Travis explores the evolution of the immune system.

Childhood Immune Maturation and Allergy Development: Regulation by Maternal Immunity and Microbial Exposure

“…62,63 It is likely that our immune system has evolved as much to manage and exploit beneficial microbes as to fend off pathogens. 64,65 The gut microbiota differs during the first months of life in children who later do or do not develop allergic disease, [66][67][68] and the diversity of the microbiota may play an important role in regulating allergy 69,70 and mucosal immune development. 63 To what extent the maternal gut microbiota composition influences that of her offspring is not yet fully clear.…”

Zinc in evolution

“…A source of information about duplication is the immune system in which novel proteins, antibodies, arise very quickly with but small local changes in a binding region but not in the backbone giving a great variety of proteins [37]. The case of this multiplication is considered to be local modification of DNA, which arises from the more or less direct effect of the antigen.…”

Adoptive transfer of naïve dendritic cells in resolving post-sepsis long-term immunosuppression

“…The pivotal role of DC dysfunction is especially prominent in the modern management of sepsis since significant portion of patient survives initial period of hemodynamic instability [2,10,11,[23][24][25]. Since primary source of DC in sepsis are MO, any aberration in the process of emergence of dendritic cells from MO would have profound effect on ability of host to defend against pathogens.…”

“…Repetitive exposure to the same pathogen results in acquired immunity thereby eliminating subsequent intrusion with less effort and damage to the host [10]. This is advantageous to species with a long life span, and provide them with an evolutionary advantage since repetitive exposure is likely to occur during their life span [11].…”