TY - JOUR

T1 - High altitude impairs in vivo immunity in humans

AU - Smith, A.D.

AU - Oliver, S.J.

AU - Macdonald, J.H.

AU - Harper Smith, A.D.

AU - Lawley, J.S.

AU - Gallagher, C.A.

AU - Di Felice, U.

AU - Walsh, N.P.

PY - 2013/6/24

Y1 - 2013/6/24

N2 - The aim was to assess the effect of high altitude on the development of new immune memory (induction) using a contact sensitization model of in vivo immunity. We hypothesized that high-altitude exposure would impair induction of the in vivo immune response to a novel antigen, diphenylcyclopropenone (DPCP). DPCP was applied (sensitization) to the lower back of 27 rested controls at sea level and to ten rested mountaineers 28 hours after passive ascent to 3777 m. After sensitization, mountaineers avoided strenuous exercise for a further 24 hours, after which they completed alpine activities for 11–18 days. Exactly 4 weeks after sensitization, the strength of immune memory induction was quantified in rested mountaineers and controls at sea level, by measuring the response to a low, dose-series DPCP challenge, read at 48 hours as skin measures of edema (skinfold thickness) and redness (erythema). Compared with control responses, skinfold thickness and erythema were reduced in the mountaineers (skinfold thickness,−52%, p=0.01, d=0.86; erythema, −36%, p=0.02, d=0.77). These changes in skinfold thickness and erythema were related to arterial oxygen saturation (r=0.7, p=0.04), but not cortisol (r0.79), at sensitization. In conclusion, this is the first study to show, using a contact sensitization model of in vivo immunity, that high altitude exposure impairs the development of new immunity in humans.

AB - The aim was to assess the effect of high altitude on the development of new immune memory (induction) using a contact sensitization model of in vivo immunity. We hypothesized that high-altitude exposure would impair induction of the in vivo immune response to a novel antigen, diphenylcyclopropenone (DPCP). DPCP was applied (sensitization) to the lower back of 27 rested controls at sea level and to ten rested mountaineers 28 hours after passive ascent to 3777 m. After sensitization, mountaineers avoided strenuous exercise for a further 24 hours, after which they completed alpine activities for 11–18 days. Exactly 4 weeks after sensitization, the strength of immune memory induction was quantified in rested mountaineers and controls at sea level, by measuring the response to a low, dose-series DPCP challenge, read at 48 hours as skin measures of edema (skinfold thickness) and redness (erythema). Compared with control responses, skinfold thickness and erythema were reduced in the mountaineers (skinfold thickness,−52%, p=0.01, d=0.86; erythema, −36%, p=0.02, d=0.77). These changes in skinfold thickness and erythema were related to arterial oxygen saturation (r=0.7, p=0.04), but not cortisol (r0.79), at sensitization. In conclusion, this is the first study to show, using a contact sensitization model of in vivo immunity, that high altitude exposure impairs the development of new immunity in humans.

KW - PHYSIOLOGY

U2 - 10.1089/ham.2012.1070

DO - 10.1089/ham.2012.1070

M3 - Article

VL - 14

SP - 144

EP - 149

JO - High Altitude Medicine and Biology

JF - High Altitude Medicine and Biology

SN - 1527-0297

IS - 2

ER -