Cytokine dysregulation associated with exam stress in healthy medical students

The mechanisms of stress-related immune alterations have not been fully elu cidated. Cell-mediated immune responses as well as antibody and certain cyt okines are reported as being suppressed during times of high stress. Howeve r, the role of suppression vs dysregulation has not been established in hum an stress models. The effect of exam stress on regulatory cytokines in 16 h ealthy medical students was assessed by measuring type-1 (IFN-gamma) and ty pe-2 (IL-10) cytokines from 72-h PHA/PMA-stimulated PBMC 4 weeks before and 48 h after exams. Results demonstrated decreased IFN-gamma accompanied by increased IL-10 during exam stress that resulted in a decreased IFN-gamma:I L-10 ratio. There was a significant correlation between the cytokine respon se to PHA/PMA and number and subjective adjustment to daily hassles. Additi onally, students who reported greater levels of loneliness also reported gr eater numbers of and poorer subjective adjustment to hassles. The differenc es were consistent in both males and females but did not correlate with AM cortisol levels. Additionally, when individuals were grouped into high vs l ow preexam hassle levels, the type-1/type-2 shift in the IFN-gamma:IL-10 ra tio occurred in the low hassles group only. These data suggest that psychol ogically stressful situations shift type-1/type-2 cytokine balance toward t ype-2 and result in an immune dysregulation rather than overall immunosuppr ession. This may partially explain the increased incidence of type-2-mediat ed conditions such as increased viral infections, latent viral expression, allergic/asthmatic reactions, and autoimmunity reported during periods of h igh stress. (C) 1998 Academic Press.