Living for long periods in extreme environments-like Antarctic research stations or space missions-can have a significant impact on human health, especially on the immune system. Scientists have observed that people in such isolated conditions often experience more infections and a reactivation of viruses that usually stay dormant in the body, such as Herpes viruses. These changes affect both parts of the immune system: the rapid-response "innate" system and the slower, more specific "adaptive" system. These immune disruptions may be caused by multiple stressors: ongoing psychological stress, disturbed sleep and light cycles (circadian rhythm disruption), and the challenges of living in confined, isolated, and extreme environments. While space missions and Antarctic overwintering programs have provided some insight into these issues, scientists still lack a detailed understanding of how the immune system adapts-or fails to adapt-over time in such conditions. To help fill this gap, the CHOICE Kerguelen 2 study will follow a group of healthy young adults who will spend one year (from November 2025 to November 2026) in Port-aux-Français, a remote French research station on the Kerguelen Islands in the sub-Antarctic. These volunteers are participating in a civic service program and will be living in a highly isolated environment for the duration of their mission. The CHOICE Kerguelen study is conducted in collaboration with the French Polar Institute (IPEV). The goal of the study is to collect and store a broad range of biological samples-including blood, saliva, stool, urine, and hair-from these volunteers at four time points during the time of their confinement on the Kerguelent Islands: tevery three months during their stay. These samples will be than analyzed to characterize the immune profiles and intestinal microbiota of the subjects assess eventual viral reactivations and stress biological markers. These analyses will allow to better understand how the immune system reacts to prolonged isolation, and to identify immune profiles that may develop under prolonged stress and limited social contact. The long-term aim of this project is not only to improve our understanding of human immunity in extreme environments, but also to inform medical research for people living with chronic illness. By studying healthy individuals placed in physically and mentally challenging environments, scientists can better understand how stress and isolation may weaken immune defenses. The findings may one day help design new approaches to support immune health in vulnerable populations.
Study Type
OBSERVATIONAL
Enrollment
9
blood ponction
urines collection
hair collection
saliva collection
stools collection
Hôpital SAMUKER, Port-aux-français/ Archipel KERGUELEN /Terres Australes et Antarctiques Françaises
Port-aux-Français, Terres Australes Et Antarctiques Françaises, French Southern and Antarctic Lands
RECRUITINGlymphocytes subsets during overwintering on the Kerguelen Islands
lymphocytes subsets by flow cytometry
Time frame: At inclusion (3 months after the beginning of overwintering)
lymphocytes subsets during overwintering on the Kerguelen Islands
lymphocytes subsets by flow cytometry
Time frame: At 3 months (6 months after the beginning of overwintering )
lymphocytes subsets during overwintering on the Kerguelen Islands
lymphocytes subsets by flow cytometry
Time frame: At 6 months (9 months after the beginning of overwintering )
lymphocytes subsets during overwintering on the Kerguelen Islands
lymphocytes subsets by flow cytometry
Time frame: At 9 months (12 months after the beginning of overwintering )
RNAsep during overwintering on the Kerguelen Islands
RNAseq
Time frame: At inclusion (3 months after the beginning of overwintering )
RNAsep during overwintering on the Kerguelen Islands
RNAseq
Time frame: At 3 months (6 months after the beginning of overwintering )
RNAsep during overwintering on the Kerguelen Islands
RNAseq
Time frame: At 6 months (9 months after the beginning of overwintering )
RNAsep during overwintering on the Kerguelen Islands
RNAseq
Time frame: At 9 months (12 months after the beginning of overwintering )
plasmatic cytokines during overwintering on the Kerguelen Islands
plasmatic cytokines by Bioplex
Time frame: At inclusion (3 months after the beginning of overwintering )
plasmatic cytokines during overwintering on the Kerguelen Islands
plasmatic cytokines by Bioplex
Time frame: At 3 months (6 months after the beginning of overwintering )
plasmatic cytokines during overwintering on the Kerguelen Islands
plasmatic cytokines by Bioplex
Time frame: At 6 months (9 months after the beginning of overwintering )
plasmatic cytokines during overwintering on the Kerguelen Islands
plasmatic cytokines by Bioplex
Time frame: At 9 months (12 months after the beginning of overwintering )
fecal microbiota
fecal microbiota by bacterial sequencing
Time frame: At inclusion (3 months after the beginning of overwintering )
fecal microbiota
fecal microbiota by bacterial sequencing
Time frame: At 3 months (6 months after the beginning of overwintering )
fecal microbiota
fecal microbiota by bacterial sequencing
Time frame: At 6 months (9 months after the beginning of overwintering )
fecal microbiota
fecal microbiota by bacterial sequencing
Time frame: At 9 months (12 months after the beginning of overwintering )
hormonal stress markers during overwintering on the Kerguelen Islands
hormonal stress markers assessment in blood/urinary/hair by Elisa and nephelemetry
Time frame: At inclusion (3 months after the beginning of overwintering )
hormonal stress markers during overwintering on the Kerguelen Islands
hormonal stress markers assessment in blood/urinary/hair by Elisa and nephelemetry
Time frame: At 3 months (6 months after the beginning of overwintering )
hormonal stress markers during overwintering on the Kerguelen Islands
hormonal stress markers assessment in blood/urinary/hair by Elisa and nephelemetry
Time frame: At 6 months (9 months after the beginning of overwintering )
hormonal stress markers during overwintering on the Kerguelen Islands
hormonal stress markers assessment in blood/urinary/hair by Elisa and nephelemetry
Time frame: At 9 months (12 months after the beginning of overwintering )
stress profile during overwintering on the Kerguelen Islands
psychological stress by CST test form
Time frame: At inclusion (3 months after the beginning of overwintering )
stress profile during overwintering on the Kerguelen Islands
psychological stress by CST test form
Time frame: At 3 months (6 months after the beginning of overwintering )
stress profile during overwintering on the Kerguelen Islands
psychological stress by CST test form
Time frame: At 6 months (9 months after the beginning of overwintering )
stress profile during overwintering on the Kerguelen Islands
psychological stress by CST test form
Time frame: At 9 months (12 months after the beginning of overwintering )
EBV viral reactivations during overwintering on the Kerguelen Islands
EBV in blood and saliva by quantitative PCR
Time frame: At inclusion (3 months after the beginning of overwintering )
EBV viral reactivations during overwintering on the Kerguelen Islands
EBV in blood and saliva by quantitative PCR
Time frame: At 3 months (6 months after the beginning of overwintering )
EBV viral reactivations during overwintering on the Kerguelen Islands
EBV in blood and saliva by quantitative PCR
Time frame: At 6 months (9 months after the beginning of overwintering )
EBV viral reactivations during overwintering on the Kerguelen Islands
EBV in blood and saliva by quantitative PCR
Time frame: At 9 months (12 months after the beginning of overwintering )
CMV viral reactivations during overwintering on the Kerguelen Islands
CMV in blood and saliva by quantitative PCR
Time frame: At inclusion (3 months after the beginning of overwintering )
CMV viral reactivations during overwintering on the Kerguelen Islands
CMV in blood and saliva by quantitative PCR
Time frame: At 3 months (6 months after the beginning of overwintering )
CMV viral reactivations during overwintering on the Kerguelen Islands
CMV in blood and saliva by quantitative PCR
Time frame: At 6 months (9 months after the beginning of overwintering )
CMV viral reactivations during overwintering on the Kerguelen Islands
CMV in blood and saliva by quantitative PCR
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Time frame: At 9 months (12 months after the beginning of overwintering )
HSV viral reactivations during overwintering on the Kerguelen Islands
HSV in blood and saliva by quantitative PCR
Time frame: At inclusion (3 months after the beginning of overwintering )
HSV viral reactivations during overwintering on the Kerguelen Islands
HSV in blood and saliva by quantitative PCR
Time frame: At 3 months (6 months after the beginning of overwintering )
HSV viral reactivations during overwintering on the Kerguelen Islands
HSV in blood and saliva by quantitative PCR
Time frame: At 6 months (9 months after the beginning of overwintering )
HSV viral reactivations during overwintering on the Kerguelen Islands
HSV in blood and saliva by quantitative PCR
Time frame: At 9 months (12 months after the beginning of overwintering )
TTV viral reactivations during overwintering on the Kerguelen Islands
TTV viral loads in blood and saliva by quantitative PCR
Time frame: At inclusion (3 months after the beginning of overwintering )
TTV viral reactivations during overwintering on the Kerguelen Islands
TTV viral loads in blood and saliva by quantitative PCR
Time frame: At 3 months (6 months after the beginning of overwintering )
TTV viral reactivations during overwintering on the Kerguelen Islands
TTV viral loads in blood and saliva by quantitative PCR
Time frame: At 6 months (9 months after the beginning of overwintering )
TTV viral reactivations during overwintering on the Kerguelen Islands
TTV viral loads in blood and saliva by quantitative PCR
Time frame: At 9 months (12 months after the beginning of overwintering )