Effect of Stress on the Production of Antibodies and IL-2, IL-4, and IFNγ Depending on the Time of Antigen Administration and Evaluation of the Role of Opioid Receptors.

The time of stress exposure relative to the moment of immunization affects the direction of the immunoregulatory effect of stress. In case of stress exposure preceding immunization, rotation stress stimulated the production of antibodies, while immobilization depressed it. After antigen injection, these types of stress had no significant effect on the formation of antibody-producing cells. Acute cold stress did not affect the number of antibody-forming cells before immunization, but stimulated the humoral response after it. At the same time, the effect of stress on the production of antibodies was leveled by blockade of opioid receptors with naloxone for rotation and immobilization, but was not canceled for acute cold stress. A similar pattern was revealed when analyzing the effect of stress exposure on cytokine production. Cold stress before antigen administration to mice had almost no effect on the production of IL-2, IL-4, IFNγ, while rotational and immobilization stress naloxone-dependently modulated the synthesis of IL-2 and IL-4. On the contrary, in animals subjected to stress after antigen administration, only cold stress significantly modulated the production of IL-2 and IL-4.

The Role of ß-Adrenergic Receptors in the Regulation of the Functions of Innate Immune Cells during Cold Stress In Vivo.

It was found that 10-min cold stress enhanced stimulated production of ROS, while 60-min cold stress increased both spontaneous and stimulated ROS production by peritoneal macrophages. ß-Adrenergic receptor blockade leveled the effect of 10-min stress in stimulated cultures and the effect of 60-min stress in spontaneous cultures. None variants of cold stress affected spontaneous and stimulated production of IL-1ß. We observed an increase in the production of IL-1ß in stimulated cultures from animals subjected to 10- and 60-min stress against the background of propranolol. At the same time, both variants of cold exposure, irrespective of ß-adrenergic receptor blockade, stimulated IL-10 synthesis in spontaneous and activated samples. None of the used models of cold exposure affected the phagocytic activity of peritoneal macrophages. Thus, ß-adrenergic receptors are directly involved in the regulation of cytokine production and microbicidal potential of macrophages in acute cold stress.

Effects of Monoacyltrehalose Fraction of Rhodococcus Biosurfactant on the Innate and Adaptive Immunity Parameters In Vivo.

The biosurfactant monoacyltrehalose fraction isolated from Rhodococcus ruber IEGM 231 actinobacterium suppresses antibody production, bactericidal potential, and production of IL-1ß by mouse peritoneal cells after intraperitoneal and intramuscular injection and stimulates the production of IL-10 after intraperitoneal injection. The data of in vitro experiments attest to an important role of bacterial glycolipids in the regulation of the functions of splenocytes and peritoneal macrophages.

Effects of Glycolipid Rhodococcus Biosurfactant on Innate and Adaptive Immunity Parameters In Vivo.

The glycolipid biosurfactant complex from actinobacterium Rhodococcus ruber IEGM 231 inhibits the innate and adaptive immunity parameters after intraperitoneal and intramuscular injection. Marked suppression of antibody production, bactericidal potential, and production of proinflammatory cytokines by peritoneal macrophages, detected in vivo, do not agree with the previously detected immunostimulatory activity of biosurfactants towards the immunocompetent cell cultures; this fact indicates an important role of the cell environment in the formation of immune response under the effect of bacterial glycolipids.

Regulation of the peritoneal macrophage functional activity by the MP-5 and MP-6 myelopeptides under stress.

In mice, two-hour immobilization stress inhibited zymosan-induced production by macrophages of the oxygen radicals and cytokine IL-1ß. After myelopeptides MP-5 and MP-6 were administered into mice, the stress-induced inhibition of the reactive oxygen species (ROS) and IL-1ß was abrogated. MP-5 peptide stimulated spontaneous ROS production by macrophages and reduced IL-10 production under stress. Thus, under in vivo conditions and under stress, the effect of MP-5 and MP-6 myelopeptides modulates the peritoneal macrophage activity.

Chronic cold stress modulates the function of peritoneal macrophages in vivo.

On day 7 of chronic cold stress, concentration of corticosterone in plasma was established to increase, zymosan-induced production of reactive oxygen species was activated, and IL-10 synthesis by macrophages was enhanced regardless of the opiate receptor blockade. Increase in the concentration of corticosterone was independent of the blockade of opioid receptors, whereas the zymosan-induced increase in the production of oxygen radicals and activation of the spontaneous production of IL-10 was blocked in mice by naloxone. Chronic cold stress had no effect on the production of IL-1ß and TNF-α.

Effects of ß-endorphin on the production of reactive oxygen species, IL-1ß, Tnf-Α, and IL-10 by murine peritoneal macrophages in vivo.

It has been demonstrated that ß-endorphin stimulates the zymosan-induced secretion of reactive oxygen species and suppresses the spontaneous production of IL-1ß and IL-10 by murine peritoneal macrophages in vivo.

Effect of Opiate Receptors Blockade on Microbicidal Potential and Production of IL-1ß, TNFα, and IL-10 by Peritoneal Macrophages under Stress Conditions.

Rotation stress activated spontaneous and zymosan-induced ROS production. In animals receiving naloxone against the background of rotation stress, ROS production did not increase. Immobilization stress did not change the intensity of spontaneous and zymosan-induced ROS production, but inhibited stimulated ROS production against the background of naloxone treatment. Rotation produced a naloxone-independent inhibitory effect on spontaneous and stimulated IL-1ß and TNFα production by macrophages and naloxone-dependent stimulating effect on spontaneous IL-10 production. Rotation stress did not modulate stimulated IL-10 production. In case of immobilization stress, decreased IL-1ß and TNFα production was observed in mice exposed to stress under conditions of opiate receptors blockade; IL-10 production was not affected by immobilization stress. Both types of stress significantly increased plasma corticosterone levels, while naloxone had no effect on corticosterone production.

[INFLUENCE OF COLD STRESS ON FUNCTIONAL ACTIVITY OF MOUSE PERITONEAL MACROPHAGES UNDER OPIATE RECEPTORS BLOCKADE].

The effect of 10- and 60-min cold stress was analyzed on reactive oxygen species (ROS) formation, peritoneal macrophage production of cytokines and corticosterone level under the opiate receptor blockade. It was observed that mice exposed to -20 °C for 10 min demonstrated the ROS inhibition, the effect was leveled against the background of naloxone introduction. The animal group subjected to 60-min stress on the contrary, showed the naloxone-dependent promotion of ROS product. Both variants of cold stress did not render significant effect on IL-1ß production. Against 60-min cold stress the TNF-α production was naloxone-dependently stimulated both in spontaneous and zymosan-induced cultures. IL-10 production by macrophages was improved irrespective of the cold stress duration, as well as stimulation presence or absence; and was abolished against a background of opiate receptor blockade. Therefore, the directionality of acute cold stress on the macrophage functions was dependent both on the parameters'' analyzed and on the duration of the exposure while the opiate receptor blockade significantly modified the immunoregulatory effects of hypothermia.

[Agonists of µ- and δ-Opioid Receptors in the Regulation of IL-2, IL-4 and IFN-γ Production by Peripheral Blood Cells in vitro].

It was found that ß-endorphin stimulates the PHA (phytohemagglutinin)-induced production of interleukin-4 and has no affect on the production of interferon-gamma in unfractionated leukocytic suspension. In the culture of purified CD4+ T cells, ß-endorphin does not affect the concentration of IL-2, IL-4, and IFN-γ, but stimulates the production of IL-4 and inhibits the production of IFN-γ when adding monocytes to the culture. Selective δ-agonist DADLE enhances the PHA-induced production of IL-4 in unfractionated leukocytic suspension and in CD4+ lymphocytes+monocytes system. The synthesis of IFN-γ by purified CD4+ lymphocytes is not afected by the presence of DADLE, DAGO ad Deltorphin II; but when adding monocytes to the culture, the synthesis rate decreases. ß-endorphin and selective µ-agonist DAGO enhance the production of IFN-γ by stimulated neutrophils. The production of IFN-γ in CD8+ lymphocytes is not affected by ß-endorphin. Thus, opioid peptides have a predominantly Th2 polarizing effect, which is monocyte-mediated, hindering the development of cell response by inhibiting IFN-γ, and stimulating the production of I L-4 by activating δ-receptor. On the other hand, neutrophils can enhance the production of IFN-γ by stimulating µ-receptor.

Effects of ß-endorphin on functional activity of mouse splenocytes under conditions of in vivo blockade of µ,δ-opioid receptors.

Blockade of δ-receptors with naltrindole under conditions of systemic immunization abolished the stimulatory effect of ß-endorphin (0.0005 µg/kg) on the counts of antibody-producing cells and the titer of antierythrocyte antibodies. Injection of ß-endorphin to mice led to stimulation of concanavalin A-induced proliferative activity of splenocytes and IL-4 secretion by the naloxone-dependent mechanism. The peptide did not modify the production of IL-2 and IFN-γ.

Dynorphins in regulation of immune system functions.

Dynorphins constitute a family of opioid peptides manifesting the highest affinity for κ-opiate receptors. Immune system cells are known to express a κ-receptor similar to that in the central nervous system, and as a consequence dynorphins are involved in the interaction between cells of the nervous and immune systems. In this review, data on dynorphin structure are analyzed and generalized, the κ-opiate receptor is characterized, and data on the regulation by dynorphins of functioning of the innate and adaptive immunity cells are summarized.

Effect of glycolipid Rhodococcus biosurfactant on secretory activity of neutrophils in vitro.

Glycolipid biosurfactant synthesized by nonpathogenic strain Rhodococcus ruber IEGM231 modulated the production of ROS and IL-8 by peripheral blood neutrophils in spontaneous and stimulated cultures. Secretion of IL-1ß Ð¸ TNF-α by neutrophils in the presence of biosurfactant changed insignificantly.

[Influence of beta-endorphin on the proliferative and phagocytic activity of peripheral blood cells from males and females in different age groups].

It was revealed that beta-endorphin modulation of lymphocyte proliferative activity in male donors was predominantly observed under younger age groups of 20-29 and 30-39 years, while with age it gradually decreased and disappeared as such in group of donors under 50-60 years. Meanwhile, females demonstrated prolonged modulating effect of peptide on the proliferation. In female group under 50-59 years the peptide was found to render marked promoting effect on the spontaneous proliferation in concentrations of 10(-7), 10(-8), and 10(-10) M that was induced by suboptimal PHA concentration of 10(-10) M, whereas women in the range of 30-39 years showed that beta-endorphin suppressed the PHA-induced proliferative response. Male donors in age group of 20-29 years demonstrated beta-endorphin-stimulated and in age group of 50-59 years beta-endorphin-suppressed uptake capacity of neutrophils. In female donors from all age groups the effect of beta-endorphin on neutrophil phagocyte activity was not observed.

[Effect of opioid receptor blockade on antibody response and proliferative response under stress conditions].

It is established that rotation and immobilization stress produces bidirectional effect on AFC number in spleen and on proliferative response of splenocytes. The rotation stress results in augmentation of AFC formation and promotion of spontaneous proliferative activity of splenocytes. The micro-opioid receptor blockade with naloxone, but not delta-receptor blockade with naltrindole, abolished the effects of rotation. In contrast, the immobilization stress caused the suppression of the parameters of humoral immune response and lowered spontaneous and induced proliferative activity of splenocytes. The opioid receptor blockade with naloxone was found to level the suppressive effects of immobilization, while naltrindole exhibited a less pronounced effect. Both variants of stress demonstrated the involvement of opioid system in regulation of AFC number during induction of the immune response.

ß-Endorphin effects on antibody production, proliferation, and secretion of Th1/Th2 cytokines in vivo.

Intraperitoneal injection of ß-endorphin in doses of 1, 0.01, and 0.0005 µg/kg under conditions of systemic immunization increased the count of antibody-producing cells in the spleen and the titer of anti-erythrocyte antibodies in the plasma of experimental animals. Intraperitoneal ß-endorphin stimulated proliferative activity of splenocytes in mice in the presence of both B- and T-cell mitogen, did not change the production of IFN-γ, reduced the level of IL-2, and stimulated the secretion of IL-4, the main Th2-polarizing factor.