Increased soluble human leukocyte antigen-G levels in peripheral blood from climbers on Mount Everest.
Soluble human leukocyte antigen-G (HLA-G) is involved in maternal-fetal tolerance, transplant acceptance, and tumor escape from immunosurveillance, operating by inhibiting activity of T, antigen presenting cells (APC), and natural killer (NK) cells. HLA-G gene expression is modulated in vitro after hypoxic conditions, a situation evidenced during pregnancy and tumor progression. In extreme altitude, mountaineers are in hypoxic conditions that generate physiologic adaptative responses, some of them giving rise to pathologic signs. We performed measurements of plasma soluble HLA-G in six climbers before departure of the expedition and during their ascent to and descent from summit of Mount Everest, and in 3 Sherpas at 5300-6400 m. We found that HLA-G levels are upregulated during the ascent with a unique pattern in comparison with angiogenic/lymphangiogenic factors. Our data suggest that HLA-G has to be taken into account in the mechanisms participating in adaptation to high altitudes and reinforce hypoxia as an important factor in the regulation of HLA-G expression.
Bourguignon
Michel
M
Autorité de Sûreté Nucléaire, 6 place du colonel Bourgoin, Paris Cedex, France.
Yaghi
Layale
L
Flajollet
Sébastien
S
Radanne-Krawice
Irène
I
Rouas-Freiss
Nathalie
N
Lugrin
Didier
D
Richalet
Jean-Paul
JP
Carosella
Edgardo D
ED
Moreau
Philippe
P
D000328:Adult; D000531:Altitude; D015415:Biomarkers / Q000097:blood; D004781:Environmental Exposure / Q000009:adverse effects; D004797:Enzyme-Linked Immunosorbent Assay; D005786:Gene Expression Regulation; D006680:HLA Antigens / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D006801:Humans; D000860:Hypoxia / Q000097:blood / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D009051:Mountaineering / Q000502:physiology; D010100:Oxygen / Q000378:metabolism; D013312:Stress, Physiological / Q000276:immunology
D015415:Biomarkers; D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I; D010100:Oxygen