More than a Scratch

Science Signaling  06 Dec 2011:
Vol. 4, Issue 202, pp. ec340
DOI: 10.1126/scisignal.4202ec340

Immunological T cells that express the γδ T cell receptor respond rapidly to various stressors in the skin by binding to stress-induced ligands. It is thought that this response helps to prevent dissemination of an infection or to restore tissue homeostasis after injury. The effects of this “lymphoid stress surveillance” response are primarily local; however, systemic effects on the immune response are possible. Working in mice, Strid et al. show that antigen given in the context of mild skin abrasion can induce a systemic T helper 2 (TH2)–type immune response. TH2 responses are most commonly associated with allergy and asthma. In this case, the induction of the TH2 response was dependent on lymphoid stress surveillance: Skin-resident γδ T cells were required for the response, as was the receptor NKG2D, which γδ T cells use to recognize molecules that are induced in response to physicochemical stress. Thus, skin allergies may arise when normally benign antigens are encountered at the same time as a tissue injury or abrasion.

J. Strid, O. Sobolev, B. Zafirova, B. Polic, A. Hayday, The intraepithelial T cell response to NKG2D-ligands links lymphoid stress surveillance to atopy. Science 334, 1293–1297 (2011). [Abstract] [Full Text]