title: Urinary neopterin quantification indicates altered cell-mediated immunity in healthy subjects under psychological stress.
abstract: In an effort to quantify changes in cell-mediated immunity (CMI) in healthy subjects under stress, we measured levels of neopterin, a well-validated marker of CMI activation, in the urine of medical students undergoing academic examinations. Neopterin/creatinine ratios measured on the first day of examinations (mean 46 mumol/mol) were significantly lower than those measured two weeks before (mean 78 mumol/mol, p = .004). Minimum neopterin production coincided with maximum subjective stress, as measured by a visual analogue scale. After examinations, neopterin/creatinine ratios rose (means 62 mumol/mol immediately after, and 65 mumol/mol two weeks after examinations), and these levels were not statistically different from those two weeks before examinations. Over this post-examination period, subjective distress was significantly lower than at either time point before examinations. We conclude that urinary neopterin/creatinine ratios may change significantly during periods of psychological stress, indicating concomitant alterations in CMI activation.
authors.affiliation: Department of Medicine, Wellington School of Medicine, New Zealand.
authors.forename: P R
authors.initials: PR
authors.lastname: Dunbar
authors.forename: J
authors.initials: J
authors.lastname: Hill
authors.forename: T J
authors.initials: TJ
authors.lastname: Neale
mesh_terms: D000328:Adult; D000368:Aged; D001708:Biopterins / Q000031:analogs & derivatives* / Q000652:urine; D004521:Educational Measurement; D005260:Female; D006801:Humans; D007108:Immune Tolerance / Q000276:immunology; D007111:Immunity, Cellular / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D019798:Neopterin; D011598:Psychoneuroimmunology; D012016:Reference Values; D013315:Stress, Psychological / Q000276:immunology*; D013337:Students, Medical / Q000523:psychology; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D001708:Biopterins; D019798:Neopterin