Modulation of the immune response by emotional stress

The influence of mild, emotional stress was investigated for its effect on the immune system by subjecting rats to the one-trial-learning passive avoidance test. The reactivity of the immune system was tested by determining the proliferative response after mitogenic stimulation in vitro as well as the capacity to generate a primary antibody response in vivo after immunization with sheep red blood cells. Our results demonstrate that exposure of rats to a single electric footshock (learning trial) or habituation to the passive avoidance apparatus, induces an increase of the immune response in vitro and in vivo. Thus, emotional stimuli seem to facilitate immunological responsiveness. However, when the animal is confronted with a conflict situation, as tested by the retention of the avoidance response after a single learning trial, the initially enhanced reactivity of the immune system decreases. It is concluded that the immune system is capable of reacting specifically and immediately to distinct psychological stimuli.     

Effect of the spleen extracts on primary immune response in mice]

Experiments were conducted on mice. Direct Jerne's test demonstrated a possibility of intensification of the primary immune response in the sexually mature mice under the effect of the splenic extracts. The significance of the extract dose and of the time of administration for the manifestation of the stimulating action was studied.     

Effect on the immobilization-induced stress on the immune response in mice with various behavioral stereotypes

CBA and C57BL/6J mice with aggressive and submissive types of zoo-social behavior fixed during 10-day confrontation testing demonstrated different immune response to immobilization stress. In aggressive mice with confrontation experience stress resulted in a decrease in the immune response in comparison with aggressive inexperienced mice. Therewith, the immune response of CBA mice did not differ from the control level (the immunized mice without experience of victories and defeats), and in C57BL/6 mice the immune response was two times lower than in the control. In contrast to the control and aggressive mice, stress did not suppress the immune response in submissive animals. It is suggested that stress-induced changes in the immune response depend on zoo-social rank of an individual underlain by a particular neurochemical pattern of the brain.     

Restraint stress and anti-tumor immune response in mice

Psychological stress modulates the immune system through the hypothalamic-pituitary-adrenal axis, the sympatho-adrenomedullary axis and the opioid system. According to literature data, restraint stress increases the immune cell apoptosis, decreases the spleen and thymus cell content, the natural killer (NK) activity in the spleen, and it compromises the anti-tumor immune response in mice. We immobilized mice in two consecutive nights, and then determined the cell number, apoptosis, NK cell content, NK activity and the level of cytokine mRNAs (TNF-beta, TNF-alpha, IL-4, IL-5, IL-1alpha, IFN-gamma, IL-2, IL-6, IL-1beta and IL-3) in the thymus and spleen. No consistent changes were detected in any of the immune parameters either in C57Bl/6 or in DBA/2 mice. Stressed or control B6 mice were injected with B16 melanoma cells immediately after the immobilization or one week later. No significant differences were found in the growth of primary tumors and lung metastases in stressed and control animals. Taken together, our mice, kept in a general-purpose non-SPF animal house, seemed to be refractory to the stress-induced immunomodulation. Our interpretation is that stress-induced immunomodulation can occur only in mice isolated from any background stressors, or rather natural stimuli, throughout their life.     

Effect of neutrophilokines on the immune response in mice

The influence of different peptide fractions obtained from the intact and latex-stimulated neutrophils on the immune response was studied. It was demonstrated that neutrophils after stimulation synthesize the factors activating immune response, the intact neutrophils synthesize the suppressor factors of peptide nature.     

Rosette formation and humoral immune response to 2,4-dinitrophenol in mice of different inbred strains]

A study was made of the content of rosette-forming cells to DNP-ovalbumin in the spleen of mice of different inbred strains. The values of the rosette-forming cells and of the titre of serum agglutinins to the DNP-group in DNP--bovine gamma-globulin immunization of mice of these strains were determined. It was shown that there were interstrain differences in respect to the normal and immune rosette-forming cells and also humoral antibodies. There was noted a direct correlation between the number of the immune rosette-forming cells and the antibody titre in the serum of mice of the same inbred strain. Immune response (both by the content of rosettes in the spleen and by the antibody level) proved to be the minimal in mice with the highest level of rosette-forming cells. There proved to be no inverse relationship.     

Effect of anthelminthic treatment on the immune response of mice

Immunologic function was tested both in vivo and in vitro in mice undergoing prophylactic anthelminthic therapy with three agents to assess whether these drugs affected immune responses. This study was performed because investigators often are concerned about the effect of drug treatment on the induction of specific immune responses. While helminthic infestation is recognized as deleterious to the host, it is unclear whether anthelminthic treatment might be immunosuppressive. The effects of piperazine or trichlorphon administered to drinking water or fenbendazole administered in feed were insignificant in BALB/c mice. The induction of allospecific cytolytic T lymphocytes (CTLs) in vitro, influenza specific memory T cells in vivo, influenza specific antibody secretion in vivo, or influenza-specific helper T cells and CTLs in vitro were examined. Results of this study indicate that anthelminthic treatments did not interfere with immune responses.     

以人精子抗原消化道免疫后的体液免疫反应

The inbred Balb/c and C57 mice, and the outbred Swiss Webster mice were intragastrointestinally immunized with human sperm antigens. The lymphocytes from the spleen, mesenteric lymph node (MLN), Peyer's patch (PP) and uterus or epididymis were isolated and cultured. The lymphocyte-secreting antisperm IgG and IgA and the antisperm antibodies in the gut wash and serum were determined with enzyme-linked immunosorbent assay (ELISA). In the Balb/c and Swiss Webster mice, the immune responses to sperm have shown to be stronger than that in C57, stronger in female than in male. The antigenicity of sperm membrane extracts seems to be higher than that of whole sperm. Antisperm antibodies secreted by lymphocytes from the epididymis and uterus have demonstrated to be detectable. For stimulation of the local immune response, the intra-PP and intralumina immunizations are more effective than others.     

Effect of genotype and emotional stress on hygienic grooming in inbred mice

Body care behavior (grooming) is an adaptation aimed at removing litter particles, pathogenic microbes and parasites from animal fur and skin. Moreover, it serves as an indicator of animal health. It was observed that chronic stress suppressed fur cleaning. In this article, a technique of direct measurement of fur cleaning using the cleaning dynamics of a fluorescent spot applied on animal's back is described. Significant effects of genotype and emotional stress on the dynamics of fur cleaning are shown. Mice of C57BL/6, CBA and CC57BR strains clean green fluorescent spot rapidly (1-2 h) whereas animals of AKR strain clean it slowly (up to 24 h). Behavioral restriction for 30 min substantially reduced fur cleaning in AKR, CBA and CC57BR, but not in C57BL/6. The stress-induced attenuation of Hygienic grooming is a new index of sensitivity (resistance) to stress.     

Delayed effects of cold stress on immune response in laboratory mice

This study was undertaken to examine the trade-off between the cost of thermoregulation and immune function in laboratory mice. Mice were maintained either at 23 degrees C or cold exposed at 5 degrees C for 10 days. Then, they were immunized with sheep red blood cells. Thus, the cold-exposed mice had either experienced or not experienced cold stress prior to immunization. Cold stress elicited a substantial increase in food intake, accompanied by a significant reduction in food digestibility. An increase in mass of metabolically active internal organs (small intestines, heart and kidney) was observed in cold-exposed mice. These findings reassured us that costs of increased thermoregulation caused by cold stress were substantial. The immune response of mice exposed to long-lasting cold stress was significantly lower, but immune response was not affected in short-exposed mice. Differences in immune response between experimental groups accompanied changes in mass of immunocompetent organs (thymus and spleen). Our findings indicate that studies of trade-offs should account for the fact that resource reallocation in response to an environmental challenge may not be immediate. In fact, resource reallocation may be postponed until the new environmental state becomes permanent or until an organism attains physiological adaptation to the current conditions.     

Effect of emotional stress on the frequency of meiotic abnormalities in male mice

The effect of stress on the recombination frequencies at the 1st and 2nd chromosomes of male mice was shown earlier. The purpose of this work is the study of the stress effects on the behaviour of meiotic chromosomes. Male mice (A/He and DD/J inbred strains) were treated with acute immobilizing stress at different periods, prior to killing. It was shown that the stress significantly increases the frequency of X-Y and autosomal univalents in metaphase 1 and aneuploidy in metaphase 2. The most sensitive to the stress are the late interphase - early leptotene cells.     

Multigenic regulation of the primary immune response to ovalbumin in mice

At least four genes regulate the primary immune response to ovalbumin in mice. The ability to be sensitized to transfer delayed type hypersensitivity to ovalbumin is controlled by two genes. One gene,OVA-, is linked to theH-2 complex and maps to the left ofI-E. The linkage of the other gene,OVA-Bg1, has not been determined, but it segregates independently of theLy M locus, of the heavy chain allotype genes and of certain genes controlling coat color. At least two genes regulate the ability to respond with a primary antiovalbumin antibody response. One gene,OVA-, is linked to theH-2 complex and maps to the right ofI-E. Discordance of the minimum dose of antigen needed to elicit delayed type hypersensitivity response and antibody suggests that non-H-2 gene(s) regulating the primary antibody response are different fromOVA-Bg1.Abbreviations used in this paper BSA bovine serum albumin - DTH delayed type hypersensitivity - H-2 major histocompatibility complex of mouse - Ir gene — immune response gene - OVA ovalbumin - SRBC sheep red blood cells     

Stability of the cardiovascular functions of different genetic strains of rats subjected to emotional stress

The level of catecholamines was measured in various brain parts in rats of August and Wistar lines, characterized by different stability of cardio-vascular functions in emotional stress. In norm, the August line has a higher content of dopamine (DA), in the mid-brain in particular; the Wistar line has a higher content of noradrenaline (NA) in the hypothalamus. In susceptible animals, which showed different cardio-vascular disorders during 30 hours of immobilization (48% of the Wistar line and 90% of the August), and in animals resistent against emotional stress, the changes in the initial level of catecholamines were observed, both common and specific for two lines. An assumption is made that the stability of cardio-vascular functions in the emotional stress is provided for by an intensive metabolism of the NA-synthesizing neurones in the brain isthmus, and by a moderate activity of the DA-synthesizing neurones of the mid-brain; the susceptibility to cardio-vascular disorders in the emotional stress is due to increase in the activity of the DA-synthesizing mid-brain neurones, the decrease in the activity of the DA-hydroxilase and the exhaustion of NA in the hypothalamus.