|The temporal relationship of psychosocial stress to cellular immunity and herpes labialis recurrences.|| ||Schmidt DD, Schmidt PM, Crabtree BF, Hyun J, Anderson P, Smith C.
| ||"This study used a prospective single-subject study design and time series analysis for repeated measures data to investigate the hypothesis that variations in psychosocial stress are associated with changes in cellular immunity in a study subject with recurrent herpes labialis. A study subject who was antibody positive for HSV-1 but reported no clinical manifestations of disease served as a control. Psychosocial stress, as measured by a questionnaire; cellular immunity, as measured by the monoclonal antibodies CD4 (OKT4), which defines the helper/inducer subset of T lymphocytes; and CD8 (OKT8), which defines the suppressor/cytotoxic subset, were measured weekly over the 32-week study period. Analysis of data using bivariate time series (ARIMA) demonstrated significant inverse correlations between stress level scores and percent CD4 helper/inducer T lymphocytes in both subjects. In the study subject with recurrent herpes simplex labialis, a Mann-Whitney U statistic determined that the percent of CD4 in the early stages of a recurrence were significantly lower than the percent of CD4 at other times when blood samples were drawn."|
| ||Fam Med 1991 Nov-Dec;23(8):594-9||1991|
|Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry.|| ||Segerstrom SC et al.
| ||Long-term stress suppresses the ability of the immune system to fight viral as well as bacterial and parasitic infections, according to a meta-analysis of almost 300 studies published in the July edition of the Pyschological Bulletin. The investigators also found that the immune systems of individuals who are older or already suppressed due to illness are more prone to stress-related change. Investigators analysed data from 296 studies conducted between 1969 and 2001 looking at the effects of stress on the immune system. They identified different categories of stress ranging from short-term acute stress provoking a “fight or flight” reaction to chronic stress without any clear endpoint. Different immune responses were also identified by the investigators. These included natural immunity, producing a fast-acting, all purpose response able to attack a variety of pathogens, and specific immunity. Specific immunity involves both a cellular response to fight viruses and other pathogens which invade the cells of the body, and humoral responses to fight bacteria and parasites. The investigators correlated how natural immunity, and cellular and humoral responses were affected by stress. They established that short-term stress which provoked a fight-or-flight response actually boosted natural immunity as the body primed itself to respond to challenges to the integrity of the skin and blood. However, the body’s short boost in natural immunity is achieved at the expense of specific immunity, which is suppressed. Chronic stress was found by the investigators to be associated with global suppression of the immune system, resulting in a drop in immune function across the board. Duration of stress was also found to be significant with the beneficial effects of short-term stress on natural immunity turning into long-term suppression of both cellular and humoral specific immune functions. Age and disease status were also found to affect an individual’s vulnerability to stress-related decreases in immune function.|
| ||Psychological Bulletin 130: 601-630, 2004.||2004|
|The effects of psychological stress on leukocyte subset distribution in humans: evidence of immune activation.|| ||Maes M, Van Bockstaele DR, Gastel A, Song C, Schotte C, Neels H, DeMeester I, Scharpe S, Janca A.
| ||"The aim of the present study was to examine the effects of academic examination stress on leukocyte subset distribution in university students. Thirty-eight university students had repeated blood collections for white blood cell differentiation and flow cytometric assay of lymphocytic subsets a few weeks before and after (i.e. two baseline conditions) as well as the day before a difficult academic examination (i.e. stress condition). Flow cytometry was used to determine the number of peripheral blood mononuclear cells (PBMC). In students, who were reactors to psychological stress..., but not in stress non-reactors, a significant increase in the number of neutrophils, monocytes, CD8(+), CD2(+)CD26(+), and CD2(+)HLA-DR+ T cells and CD19(+) B cells, and significant reductions in the CD4(+)/CD8(+) T cell ratio were observed in the stress condition...There were significant and negative relationships between the stress-induced changes in the CD4(+)/CD8(+) ratio and the stress-induced changes in the PSS scale... The results suggest that academic examination stress induces changes in the distribution of PBMC, which indicate immune activation and which are probably orchestrated by a stress-induced production of cytokines."|
| ||Neuropsychobiology 1999;39(1):1-9||1999|