Yu. I. Shilov

Protective effects of plant polyphenols on the immune system in acute stress.

Stress-induced immunosuppression is one of the key factors in pathogeneses of many diseases [1–3]. As reported in [4, 5], plant-derived substances (e.g., polyphenols) with an adaptation-promoting effect (adaptogens) can prevent stress-induced immunosuppression. Therefore, plant polyphenols seem to be promising for routine use in combined treatment and prevention of this condition [4, 5]. In turn, the development of prophylactic methods for protecting the immune system against stress is of paramount importance in many fields of medicine and biology. The purpose of this study was to evaluate the effects of plant polyphenols on stress-induced changes in the cellularity of organs of the lymphomyeloid complex (spleen, lymph nodes, bone marrow, and peripheral blood) and in their phagocytic activities in mice.

Alterations in the proliferative response of peripheral lymphocytes in tick-borne encephalitis.

It has been shown that the mechanisms of immunity play an important role in the pathogenesis of tick-borne encephalitis and stipulate the clinical polymorphism of this disease, the degree of lesions in nervous system, and the outcome of the pathological process [1–3]. Reports about the possible damaging of immune cells by the tick-borne encephalitis virus appeared recently [4, 5]. In particular, primary viremia is always accompanied by the replication of the virus in regional lymphatic nodes and in the mononuclear phagocyte system [5]. As the infection progresses, secondary viremia develops, when the virus penetrates in the central nervous system. With adequate immune response, secondary viremia and the damage of central nervous system may not occur [5]. In grave cases, necrotic changes in the thymus and the T-dependent zones of the lymphatic nodes and spleen were observed [4]. Changes in the amount of T-lymphocytes in peripheral blood were reported in several works [1, 2]; however, there was no assessment of their functional activity, including their response to T-cell mitogenes. The purpose of this work was to study the changes in the proliferative response of lymphocytes from patients with different forms of tickborne encephalitis to phytogemagglutinine.

Adrenergic regulation of phagocytic activity of peripheral blood neutrophils, monocytes, and eosinophils in stressed rats.

Time course of phagocytic activity of peripheral blood neutrophils, monocytes, and eosinophils was studied in rats exposed to acute stress under conditions of propranolol blockade of β-adrenoceptors. The important role of β-adrenergic mechanisms in the regulation of phagocytic functions in stress was demonstrated.

Adrenergic regulation of lymphocyte proliferative response in cultures with T-cell mitogens

The effects of epinephrine, β-adrenergic agonist terbutaline sulfate, and cAMP phosphodiesterase inhibitor theophylline on proliferative response of peripheral blood lymphocytes from healthy subjects were studied in cultures with phytohemagglutinin and concanavalin A. Both adrenergic agonists inhibited lymphocyte blastogenesis, but the effect of epinephrine was more pronounced.

Myelopeptides in treatment for stress- and injury-induced changes in the immune response to a heterologous thymus-dependent antigen in rats with penetrating eye wounds

3. Throughout the text of the article LOR should read DTH. Erratum: “Myelopeptides in Treatment for Stressand InjuryInduced Changes in the Immune Response to a Heterologous Thymus-Dependent Antigen in Rats with Penetrating Eye Wounds” [Doklady Biological Sciences, 2007, vol. 412, pp. 8–10] T. V. Gavrilova, N. L. Berkasova, Yu. I. Shilov, M. V. Chereshneva, and Academician V. A. Chereshnev Submitted April 5, 2007; accepted for publication April 15, 2007

The effect of polyoxidonium on immune response and morphological parameters of inflammation after experimental penetrating eye injury

75 Unique physiological features of the organ of vision and its immune status make penetrating eye injury (PEI) and its therapy a multidisciplinary problem [1–3]. PEI is an example of local injury inducing both loñal responses with the disruption of immunosuppression in the organ and general changes in the immune syss tem [1, 4]. The Russian immunostimulant Polyoxidoo nium is a promising drug for enhancing healing proo cesses in the injured eye tissues, formation of more mature and structured scar tissue [5, 6]. This study has provided evidence for the antiiinflammatory effect of Polioxidonium and its ability to attenuate inflammaa tory cell infiltration in the injured area. We have demm onstrated that, despite stimulation of secretion of antii bodies, the traumatic immunosuppression of the delayeddtype hypersensitivity response (DHR) to thyy mussdependent xenoantigen occurs shortly after the injury. This offers new prospects in discovering the mechh anism of the immunomodulation effect of this drug. The study was performed on 119 white male rats weighing 213 ± 4 g. Penetrating injury of the right eye was inflicted under 2% procaine anesthesia [6]. On the first stage of the study, the immunomodulation effect of polyoxidonium alone or together with standard therapeutic protocol for PEI during immune response to sheep erythrocytes was evaluated. The injured anii mals were divided into four groups (Table 1). The fifth group included control animals (the PEI was not inflicted, while the right eye was sham anesthetized with 0.9% NaCl). All drugs were administered 6 h after the injury. Standard therapeutic drugs were adminiss tered subcutaneously (0.1 mg/kg dexamethasone phosphate once a day; 0.5 mg/kg sodium diclofenac, 12.5 mg/kg sodium ampicillin, and 1.5 mg/kg gentamii cin sulfate twice a day). Polyoxidonium (0.1 mg/kg) was administered 6 h, two days, and four days after the injury. To induce the immune response, all rats were sensitized with sheep erythrocytes (10 8 cells subcutaa neously in the right foot sole) 7 h after the beginning of the experiment. On day 4, the antigen was adminiss tered subcutaneously (10 9 sheep erythrocytes in the right sole, and 0.1 mL of 0.9% NaCl in the left sole). On day 5, all animals were anesthetized with ether and decapitated. The endocrine response was evaluated by the number of antibodyyforming cells in the regional (popliteal) lymph node, which was evaluated by local hemolysis in agarose gel [7]; the DHR was evaluated by the response index [8]. …

Effect of Female Sex Steroid Hormones on the Functions of the Peripheral Blood Phagocytizing Cells

Estrogens and gestagens exhibit a strong immunomodulating activity and determine the reproductionrelated immune changes at the local and systemic levels, which are characteristic of female organisms [1, 2]. Earlier, we showed that estradiol decreases the amount of bone marrow stem cells and depresses the reduction of the amount of T lymphocytes after irradiation of mice with shielded bone marrow without affecting the functional activity of B lymphocytes in the same system [1]. In the model with syngeneic transfer of immunocompetent cells to the mice that were exposed to lethal radiation doses, this hormone stimulates humoral immune response predominantly at the stage of antigen-dependent interaction of immunocompetent cells [3]. Progesterone and other gestagens suppress cellular immune response without affecting antibody formation [1, 3]. During pregnancy and the lutein phase of the menstrual period, progesterone and estradiol are involved in switching the cytokine profile to the Th2 type during the immune response [2, 4–6]. It was clearly demonstrated that estrogens and, to a lesser extent, gestagens stimulate different functions of the mononuclear phagocyte system cells [1, 7, 8]. However, the involvement of the female sex steroid hormones in the regulation of functions of other phagocytizing and nonspecific effector cells (neutrophils and eosinophils, in particular) has been studied much poorer. For example, different studies on the effect of estradiol on the reactive oxygen species production by neutrophils in vitro showed activation [1], suppression [9], and an absence of any effect [10]. Because the effects of hormones at the organismal level are determined not only by their direct effect on the target cells, but also by the changes caused by cell release from the bone marrow and their migration to tissues, in vivo studies are more preferable for an integral estimation of the changes occurring in the functions of the circulating pool of phagocytizing cells. The purpose of this study was to analyze the effect of estradiol and progesterone on the quantitative and functional parameters of the circulating pool of phagocytizing cells. The study was performed on ovariectomized female Wistar rats weighing 214.5 ± 7.6 g. The rats were given subcutaneous injections of estradiol (0.025 mg per animal singly) or progesterone (2 mg a day per animal for seven days). The doses and schemes of injections were selected based on the study of production of these hormones under various physiological conditions. The leukocyte phagocytic activity was assessed by the method described in [11] with some modifications. Briefly, heparin-treated blood (25 μ l) was mixed in antiadhesive tubes with formalin-treated sheep erythrocyte suspension (25 μ l, 100 × 10 6 cells per ml) prepared in medium 199 supplemented with 2 mM L-glutamine and 10 mM HEPES. The specimens were incubated at 37 ° C for 20 min. The results were estimated microscopically with respect to the complex of parameters that was described earlier [12]. Oxygen-dependent mechanisms of bactericidal activity were analyzed spectrophotometrically in a modified test using nitro blue tetrazolium (NBT) [13]. In the stimulation experiment, 25 μ l of blood were mixed with 12.5 μ l of opsonized zymosan (3.0 mg/ml; Sigma, United States), 12.5 μ l of nutrition medium (medium 199 supplemented with 2 mM L-glutamine and 10 mM HEPES), and 25 μ l of 0.15% NBT. The next steps of determination did not differ from those described in [13], except that the volumes of all reagents were increased by a factor of 1.5. The statistical significance of the differences was evaluated using paired Student’s t test, paired Wilcoxon’s sign í test, and Wilcoxon’s sum-of-ranks W test. We found that the estradiol injections to ovariectomized rats had differential, oppositely directed effects on the phagocytic activity of neutrophils, monocytes, and eosinophils. Six hours after the estradiol injection, the amount of neutrophils in the peripheral blood increased (Table 1). This was apparently related to their release from the bone marrow, because the amount of young neutrophil forms simultaneously increased (the overall number of stab and young neutrophils in 1 μ l of PHYSIOLOGY

Effect of hydrocortisone on the functions of the circulating pool of phagocytizing cells under the conditions of beta-adrenergic blockade.

It is generally believed that the functions of phagocytizing cells are suppressed by glucocorticoids. It has been shown that glucocorticoids suppress the clearance function of the cells of the mononuclear phagocyte system [1] and inflammatory leukocyte migration [2, 3], reduce expression of the receptors for the Fc immunoglobulin fragment [2] and cell adhesion molecules [3], and inhibit secretion of anti-inflammatory cytokines and other inflammation mediators [2, 3]. It is known that glucocorticoids also stimulate the expression of β 2 -adrenergic receptors [4]. However, the contribution of this effect to the alteration of phagocytizing cell functions is not understood completely. It is not established yet which effects of glucocorticoids are direct and which occur via changes in β -adrenergic receptor expression.

Effects of Hydrocortisone on Peritoneal Phagocytizing Cells in Rats under Conditions of β-Adrenoceptors Blockade

Hydrocortisone decreased the count of peritoneal mononuclear phagocytes and mast cells and total phagocytic activity of peritoneal phagocytes in rats, but had no effect on the nitroblue tetrazolium test. β-Adrenoceptor blockade abolished the suppressive effect of hydrocortisone on phagocytosis and prevented the decrease in the count of mast cells, but markedly reduced the number of neutrophils and parameters of stimulated nitroblue tetrazolium test.

Contribution of the reproductive hormones to the regulation of prostaglandin F2α production by immunocompetent cells

The ability of estradiol, progesterone, and chorionic gonadotropin to influence prostaglandin F2α production by intact splenocytes of CBA mice was studied. Estradiol and progesterone similarly activated the processes of prostaglandin F2α production. No relationship was revealed between the effect and the concentration of the hormones. Chorionic gonadotropin activated prostaglandin production by immunocompetent cells but only when used in a concentration reflecting the peak of its physiological secretion. Combining gonadotropin with estradiol or progesterone did not lead to any appreciable differences in the prostaglandin-stimulating action of each hormone alone.