Age and sex modulate effects of stress on the immune system: a multivariate analysis

Deciphering sex differences in the immune system and depression

Certain mood disorders and autoimmune diseases are predominately female diseases but we do not know why. Here, we explore the relationship between depression and the immune system from a sex-based perspective. This review characterizes sex differences in the immune system in health and disease. We explore the contribution of gonadal and stress hormones to immune function at the cellular and molecular level in the brain and body. We propose hormonal and genetic sex specific immune mechanisms that may contribute to the etiology of mood disorders.

Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry

The present report meta-analyzes more than 300 empirical articles describing a relationship between psychological stress and parameters of the immune system in human participants. Acute stressors (lasting minutes) were associated with potentially adaptive upregulation of some parameters of natural immunity and downregulation of some functions of specific immunity. Brief naturalistic stressors (such as exams) tended to suppress cellular immunity while preserving humoral immunity. Chronic stressors were associated with suppression of both cellular and humoral measures. Effects of event sequences varied according to the kind of event (trauma vs. loss). Subjective reports of stress generally did not associate with immune change. In some cases, physical vulnerability as a function of age or disease also increased vulnerability to immune change during stressors.

Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry

The present report meta-analyzes more than 300 empirical articles describing a relationship between psychological stress and parameters of the immune system in human participants. Acute stressors (lasting minutes) were associated with potentially adaptive upregulation of some parameters of natural immunity and downregulation of some functions of specific immunity. Brief naturalistic stressors (such as exams) tended to suppress cellular immunity while preserving humoral immunity. Chronic stressors were associated with suppression of both cellular and humoral measures. Effects of event sequences varied according to the kind of event (trauma vs. loss). Subjective reports of stress generally did not associate with immune change. In some cases, physical vulnerability as a function of age or disease also increased vulnerability to immune change during stressors.

Modulation of the immune response by changing neuromediator systems activity under stress

The possible correction of the immune response affecting the mechanisms of neuroimmunomodulation in the animal model of immobilization stress is considered. Immobilization (3 h on the back) of CBA mice caused a suppression of the immune response. The number of plaque-forming cell (PFC) on the 4th day as well as rosette-forming cell (RFC) number on the 5th day of the immune reaction to sheep red blood cells (SRBC) were found to be reduced as compared to the control. Immunoinhibition in the stressed mice was reversed by the depletion of the cerebral serotonin (5-HT) with p-chlorophenylalanine (PCPA) 2 days before immobilization at a dose of 500 mg/kg. Activation of postsynaptic D-1 and D-2 dopamine (DA) receptors with apomorphine administered 30 min before stress attenuated stress-induced immunosuppression as well. Thus, the immunosuppression elicited by a stressor can be modified by drugs influencing the 5-HT and DAergic systems. It is suggested that the stress-provoked alterations of the immune response can be a consequence of changing neurochemical pattern of the brain and the disturbances of the mechanisms of psychoneuroimunomodulation.

Lymphocyte protein synthesis: evidence that murine T cells are more affected by stress than B cells

B and T cells present in the spleen and other sites of the immune system play a crucial role in the protection of individuals by mounting a specific primary and secondary immune response. Disturbances in their signaling and functioning could lead to a deterioration of the defense mechanisms and thereby lead to infections, pathologies or diseases. In this work, we studied the effects of stress on the protein synthesis and metabolism of mouse splenocytes. The study was done by radiolabeling the entire mouse with 35S-methionine (in vivo procedure) or by culturing spleen cells under various conditions of stimulation in the presence of 35S-methionine (in vitro labeling). The stimulus was lipopolysaccharide (LPS), LPS + interleukin-4 (IL-4) and concanavalin A (on A). Samples from immobilization stressed and control animals were studied in parallel. The results showed minimum alterations due to stress on B cells, though a small decrease in proliferative capacity was observed. In contrast, T cells are profoundly affected by stress. More than 100 new proteins are expressed on 2D-gel patterns of T cells from stressed animals as compared with controls, some of which could be implicated in different signaling, or could have appeared because of an alteration in a pathway of synthesis, or even as a consequence of a change in the composition of T cell populations induced by stress.