J Counotte1, H A Drexhage2, J M Wijkhuijs3, R Pot-Kolder4, V Bergink5, H W Hoek6, W Veling7. 1. Parnassia Psychiatric Institute, Kiwistraat 43, 2552 DH The Hague, The Netherlands. Electronic address: j.counotte@parnassia.nl. 2. Erasmus Medical Center Rotterdam, Department of Immunology, PO Box 2040, 3000 CA Rotterdam, The Netherlands. 3. Health E-Solutions, Westplein 11, 3016 BM Rotterdam, The Netherlands. 4. Parnassia Psychiatric Institute, Kiwistraat 43, 2552 DH The Hague, The Netherlands; VU University, Department of Clinical Psychology, de Boelelaan 1105, 1081 HV Amsterdam, The Netherlands. 5. Erasmus Medical Center Rotterdam, Department of Psychiatry, PO Box 2040, 3000 CA Rotterdam, The Netherlands. 6. Parnassia Psychiatric Institute, Kiwistraat 43, 2552 DH The Hague, The Netherlands; University of Groningen, University Medical Center Groningen, Department of Psychiatry, PO Box 30.001, 9700 RB Groningen, The Netherlands; Columbia University, Mailman School of Public Health, Department of Epidemiology, 722 West 168th Street, NY 10032, New York, NY, USA. 7. University of Groningen, University Medical Center Groningen, Department of Psychiatry, PO Box 30.001, 9700 RB Groningen, The Netherlands.
Abstract
BACKGROUND: Psychotic disorders are characterized by a deranged immune system, including altered number and function of Natural Killer (NK) and T cells. Psychotic disorders arise from an interaction between genetic vulnerability and exposure to environmental risk factors. Exposure to social adversity during early life is particularly relevant to psychosis risk and is thought to increase reactivity to subsequent minor daily social stressors. Virtual reality allows controlled experimental exposure to virtual social stressors. AIM: To investigate the interplay between social adversity during early life, cell numbers of NK cells and T helper subsets and social stress reactivity in relation to psychosis liability. METHODS: Circulating numbers of Th1, Th2, Th17, T regulator and NK cells were determined using flow cytometry in 80 participants with low psychosis liability (46 healthy controls and 34 siblings) and 53 participants with high psychosis liability (14 ultra-high risk (UHR) patients and 39 recent-onset psychosis patients), with and without the experience of childhood trauma. We examined if cell numbers predicted subjective stress when participants were exposed to social stressors (crowdedness, hostility and being part of an ethnic minority) in a virtual reality environment. RESULTS: There were no significant group differences in Th1, Th2, Th17, T regulator and NK cell numbers between groups with a high or low liability for psychosis. However, in the high psychosis liability group, childhood trauma was associated with increased Th17 cell numbers (p = 0.028). Moreover, in the high psychosis liability group increased T regulator and decreased NK cell numbers predicted stress experience during exposure to virtual social stressors (p = 0.015 and p = 0.009 for T regulator and NK cells, respectively). CONCLUSION: A deranged Th17/T regulator balance and a reduced NK cell number are associated intermediate biological factors in the relation childhood trauma, psychosis liability and social stress reactivity.
BACKGROUND:Psychotic disorders are characterized by a deranged immune system, including altered number and function of Natural Killer (NK) and T cells. Psychotic disorders arise from an interaction between genetic vulnerability and exposure to environmental risk factors. Exposure to social adversity during early life is particularly relevant to psychosis risk and is thought to increase reactivity to subsequent minor daily social stressors. Virtual reality allows controlled experimental exposure to virtual social stressors. AIM: To investigate the interplay between social adversity during early life, cell numbers of NK cells and T helper subsets and social stress reactivity in relation to psychosis liability. METHODS: Circulating numbers of Th1, Th2, Th17, T regulator and NK cells were determined using flow cytometry in 80 participants with low psychosis liability (46 healthy controls and 34 siblings) and 53 participants with high psychosis liability (14 ultra-high risk (UHR) patients and 39 recent-onset psychosispatients), with and without the experience of childhood trauma. We examined if cell numbers predicted subjective stress when participants were exposed to social stressors (crowdedness, hostility and being part of an ethnic minority) in a virtual reality environment. RESULTS: There were no significant group differences in Th1, Th2, Th17, T regulator and NK cell numbers between groups with a high or low liability for psychosis. However, in the high psychosis liability group, childhood trauma was associated with increased Th17 cell numbers (p = 0.028). Moreover, in the high psychosis liability group increased T regulator and decreased NK cell numbers predicted stress experience during exposure to virtual social stressors (p = 0.015 and p = 0.009 for T regulator and NK cells, respectively). CONCLUSION: A deranged Th17/T regulator balance and a reduced NK cell number are associated intermediate biological factors in the relation childhood trauma, psychosis liability and social stress reactivity.