Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Neuroimmunomodulation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 361 records · Page 20Linked to original sources

Topography of the enteric nervous system in Peyer's patches of the porcine small intestine.

The mechanisms of intercommunication between the immune and nervous systems are not fully understood. In the case of the intestine, the enteric nervous system is involved in the regulation of immune responses. It was therefore decided to employ immuno-histochemical techniques to investigate the structural organization of the enteric nervous system in Peyer's patches of the porcine small intestine. Using antibodies against various nervous system-specific markers (protein gene product 9.5, neuron-specific enolase, neurofilament 200, S-100 protein and the glial fibrillary acidic protein), an intimate and specific structural association could be demonstrated between enteric nerves and the compartments of Peyer's patches: follicles, interfollicular regions and domes. Peyer's patches have a close topographical relationship to the two submucosal plexuses. Enteric nerves are located around the follicle in the interfollicular area--the so-called "traffic area"--and in the dome area, which plays an important role in the uptake and presentation of antigens.

Animals↗

Pituitary adenylate cyclase-activating peptide (PACAP) immunolocalization in lymphoid tissues of the rat.

Pituitary adenylate cyclase activating peptide (PACAP) is a novel peptide isolated from the ovine hypothalamus. PACAP exists in 2 molecular forms with 27 (PACAP27) or 38 (PACAP38) amino acid residues. PACAP localization was studied by immunohistochemical methods in central (bone marrow and thymus) and peripheral (spleen, lymph nodes and duodenal mucosa) lymphoid tissues with antisera raised against PACAP27 or PACAP38. PACAP-positive cells were found in all lymphoid tissues examined. These cells were highly positive for PACAP38 but were negative for PACAP27. Morphologically, they were small mononuclear cells with relatively scarce cytoplasm and lymphocyte-like features. PACAP38-positive cells were abundant in peripheral lymphoid tissues (i.e., mesenteric lymph nodes). In the duodenal mucosa, PACAP38-positive cells were located either in the lamina propria or epithelium. These results suggest that PACAP38-positive cells are present within lymphoid tissues and may represent a lymphocyte-like cell subpopulation that has a potential role in cell-to-cell interactions in the immune system and in the integrated communication between neuroendocrine and immune systems.

Animals↗

Degranulation of eosinophilic granule cells induced by capsaicin and substance P in the intestine of the rainbow trout (Oncorhynchus mykiss Walbaum).

Adult rainbow trout (Oncorhynchus mykiss) were injected intraperitoneally with capsaicin, substance P, serotonin, or a control of saline vehicle or bovine serum albumin (0.5 microgram/g body weight). Fish were sacrificed 30 min and 1, 2, and 4 h post-injection, the gut was dissected out, and a small section of the upper intestine was processed for electron microscopy. A significant proportion of eosinophilic granule cells (EGCs) of the intestine were in close association with non-myelinated neuronal bundles in all fish (4 fish per treatment and time period), but there was no significant difference between treatment or time, suggesting that the association was unaffected by these factors. Close examination of EGC ultrastructure showed that fish treated with capsaicin and substance P exhibited limited degranulation of the EGCs in the stratum compactum and extensive crinophagic-like degranulation in the lamina propria. Cells of the lamina propria contained characteristic multivesicular-like bodies. The degranulation was reminiscent of both mast cell degranulation and endocrine cell crinophagy. EGCs of fish treated with serotonin or a control were unaffected, suggesting that the serotoninergic neurons, believed to be involved in gut motility, were not responsible for degranulation. It is apparent that EGCs of the trout intestine may be under nervous control, as has been demonstrated previously for mammalian mast cells.

Animals↗

A randomized study of neuroimmunotherapy with low-dose subcutaneous interleukin-2 plus melatonin compared to supportive care alone in patients with untreatable metastatic solid tumour.

Recent advances in our knowledge of psychoneuroimmune interactions involved in the control of tumour growth have shown the possibility of manipulating host anticancer defenses through a neuroimmunotherapeutic strategy. In particular, our previous studies have demonstrated that the concomitant administration of the pineal neurohormone melatonin may amplify the antitumour efficacy of interleukin-2 (IL-2) in humans. On this basis, a study was planned to investigate the influence of neuroimmunotherapy with low-dose IL-2 plus melatonin on survival time and on performance status in untreatable metastatic cancer patients. The study included 100 patients with metastatic solid tumours, for whom no standard therapy was available. They were randomized to receive IL-2 (3 x 10(6) IU/day subcutaneously for 4 weeks) plus melatonin (40 mg/day orally) or supportive care alone. Partial tumour regressions were seen in 9/52 (17%) patients treated with the immunotherapy, and in none of the patients treated with supportive care alone. The percentage of survival at 1 year was significantly higher in patients treated with IL-2 and melatonin than in those receiving the supportive care alone (21/52 versus 5/48, P < 0.005). Moreover, the performance status improved in 22/52 patients of the immunotherapy group and in only 8/48 patients treated with supportive care (P < 0.01). This study shows that cancer neuroimmunotherapy with low-dose IL-2 and the pineal hormone melatonin may prolong survival time and improve the quality of life of patients with metastatic solid tumours who do not respond to conventional therapies.

Administration, Oral↗

Invertebrate and vertebrate neuroimmune and autoimmunoregulatory commonalties involving opioid peptides.

1. Evidence for bidirectional interrelationships between the nervous system and immune systems of vertebrates and invertebrates involving opioid peptides is briefly discussed. 2. The involvement of opioid peptides in autoimmunoregulatory communication also is discussed. 3. The presence of mammalian interleukin-like (1 & 6) and tumor necrosis factor-like molecules in invertebrates is reviewed as well as an apparent cascading system for these signal molecules. 4. The significance of ACTH and MSH in cellular immunosuppression and autoimmunoregulation is discussed in the context of a potential role in schistosomiasis and human immunodeficiency virus actions. 5. The review concludes with the hypothesis that the mammalian immune system has its origin in the invertebrate immune/defense system given the many similarities noted in the review based on new knowledge about the more "primitive" system.

Animals↗

Inhibition of anti-CD3 monoclonal antibody-induced T-cell proliferation by dexamethasone, isoproterenol, or prostaglandin E2 either alone or in combination.

1. The purpose of these studies was to investigate the modulation of the proliferation of human T cells obtained from peripheral blood by dexamethasone (DEX), isoproterenol (ISO), and prostaglandin E2 (PGE2). The former two substances interact with T cells via the glucocorticoid and beta-adrenergic receptors respectively. When occupied by their natural ligands, glucocorticosteroids and catecholamines, these receptors have a role in modulating T-cell function during stress. During the inflammatory response increased levels of PGE2 bind to their receptors on T cells and thus alter responsiveness. Proliferation of T cells was induced by immobilized anti-CD3 monoclonal antibody (mAb) in the presence or absence of an additional costimulatory signal delivered by anti-CD28 mAb. 2. Various physiologic concentrations of DEX, ISO, or PGE2 were added at the time of initiation of the cultures and subsequent proliferation of the unstimulated T cells was determined. The results demonstrate that physiologic concentrations of all three of these agents inhibit the anti-CD3 mAb-induced proliferation of T cells. 3. Although DEX and PGE2 were equipotent in suppressing T-cell proliferation, ISO was much less effective. 4. Because concomitant elevations in the peripheral levels of these substances may occur, experiments were performed to determine the T-cell inhibitory effects of DEX together with either PGE2 or ISO. Synergistic suppression of T-cell proliferation was observed when various concentrations of DEX and PGE2, but not DEX and ISO, were added to cultures. This synergistic suppression could not be explained by an increase in cAMP accumulation in T cells stimulated with DEX and PGE2. 5. Finally, the addition of anti-CD28 mAb to anti-CD3 mAb-stimulated T cells overcame much of the suppression of proliferation induced by PGE2 or ISO but less so than that induced by DEX.

Antibodies, Monoclonal↗

The presence of immunoreactive vertebrate bioactive peptide substances in hemocytes of the freshwater snail Viviparus ater (Gastropoda, Prosobranchia).

1. Using an immunocytochemical procedure a wide range of immunoreactive vertebrate bioactive peptides (BAPs) has been found in hemocytes of Viviparus ater: bombesin, calcitonin, CCK-8, CCK-39, GH, glucagon, insulin, oxytocin, neurotensin, secretin, serotonin, somatostatin, substance P, vasopressin, and VIP. 2. No immunostaining was observed for antigastrin and antithyroglobulin antibodies. 3. The presence of BAP-like molecules in hemocytes suggests a correlation between hemocyte and APUD cells and is evidence of a relationship between the neuroendocrine and the immune systems.

APUD Cells↗

Corticotropin-releasing factor-induced immunosuppression in human and invertebrate immunocytes.

1. Corticotropin-releasing factor (CRF) appears to be a potentially important signal molecule in both vertebrate and invertebrate neuroimmune and autoimmunoregulatory processes. It appears to mimic the effects of alpha-melanocyte stimulating hormone (MSH) but has a longer duration of action. 2. alpha-Helical CRF, a specific inhibitor of CRF, antagonizes CRF-induced cellular immunosuppression but is ineffective in altering MSH-induced immunosuppression. 3. Both human and Mytilus immunocytes appear to have specific CRF receptors. 4. In another experiment, both CRF and MSH antagonize tumor necrosis factor stimulation of immunocytes. Again, alpha-helical CRF antagonizes only CRF activity, further suggesting the presence of a separate CRF receptor on these cells.

Animals↗

Immunoreactive growth hormone production by human lymphocyte cell lines.

1. Two human lymphocyte cell lines, a T-cell line and a B-cell line, were shown to produce and secrete immunoreactive growth hormone (irGH). The irGH molecules secreted by the two cell lines appeared to be de novo synthesized and their molecular size was similar to that of pituitary GH as well as irGH secreted by peripheral blood lymphocytes. 2. Affinity-purified irGH molecules had human growth hormone (hGH)-like mitogenic activity on Nb2 cells. These findings indicate that the irGH molecules produced by H9 and IM9 were similar to hGH in structure. 3. However, the irGH messages could not be amplified by polymerase chain reaction (PCR) primers which had been demonstrated to be able to amplify reverse-transcribed hGH messenger RNA successfully, suggesting that the lymphocyte-derived irGH and pituitary hGH are not exactly identical molecules. 4. We conclude that the H9 and IM9 cells produce a growth hormone-related molecule whose structure is different from that in the anterior pituitary.

Animals↗

The macrophage-activating properties of growth hormone.

1. We compared the ability of growth hormone (GH) and a well-characterized macrophage-activating factor, interferon-gamma (IFN-gamma) to activate highly purified populations of alveolar macrophages. Both GH and IFN-gamma primed macrophages triggered with opsonized zymosan to secrete superoxide anion (O2-) in vitro, but IFN-gamma was effective at a 40-fold lower concentration. Antibody blocking studies demonstrated that the priming activity of GH was independent of IFN-gamma, and the activity of IFN-gamma was distinct from that of GH. 2. Both IFN-gamma and GH increased the capability of macrophages to kill Pasteurella multocida in vitro. 3. Hypophysectomized rats challenged with Salmonella typhimurium were significantly protected by injections of either GH or recombinant rat IFN-gamma in vivo compared to vehicle-treated controls, and the protective effect of GH was increased by incorporation into liposomes. 4. Insulin-like growth factor-I (IGF-I) also primed alveolar macrophages in vitro, which is consistent with the idea that the protective effects of GH in vivo might be mediated by augmenting the synthesis of IGF-I. These data support the concept of reciprocal systems of communication between the neuroendocrine and immune systems.

Animals↗

Catecholamines induce alterations of distribution and activity of human natural killer (NK) cells.

Catecholamines have been suggested to be responsible for altered cellular immunity after stress. This study was performed to determine the effects of adrenaline and noradrenaline on lymphocyte subpopulations and NK cell functions. Subjects were given a subcutaneous injection of either NaCl, adrenaline (5 micrograms/kg), or noradrenaline (10 micrograms/kg). Catecholamine concentrations, subsets of peripheral blood lymphocytes, NK activity, and antibody-dependent cellular cytotoxicity (ADCC) were analyzed before (baseline) and 5, 15, 30, 60, and 120 min after injection. There were no differences between groups in the distribution of CD2+ and CD8+ lymphocytes over time. However, CD3+ and CD4+ T cells decreased significantly 5 to 60 min after injection of adrenaline. In contrast, NK cell numbers (CD16+, CD56+) increased significantly 5 min after injection of adrenaline and noradrenaline, reached the highest values 15 to 30 min postinjection, and subsequently declined to baseline values 60 (noradrenaline) and 120 (adrenaline) min, respectively, after injection. Similar alterations for NK activity and ADCC were observed after administration of both catecholamines. These data suggest that both sympathetic-adrenal hormones are similarly potent modulators of natural immunity and provide further evidence that catecholamines might be responsible for the observed alterations in immune functions after phases of acute stress.

Adult↗

Functional characteristics of the mature and developing brain following neuroimmunization: analysis of short-term plasticity in the rat hippocampus.

The influence of neuroimmunization by the total antigens of the cytosol fraction of hippocampal tissue or neocortical tissue on the indices of short-term plasticity in adult and developing (3 to 4 week old) Wistar rats has been investigated. Short-term plasticity was evaluated on the basis of changes in the slow-wave component of the focal potentials (FP) of the CA3 field of the hippocampus upon stimulation of the region of the dentate gyrus. The FP were recorded under nembutal anesthesia. In the groups of the hippocampus of adult and developing immunized rats, the greatest changes in short-term plasticity in the form of extreme intensification of the expressivity of the properties of paired facilitation and frequency potentiation were confined to the pyramidal layer. In the neocortex groups, the changes, as a rule, were less marked, and had the opposite sign; the main differences were found in the recording of the FP in the zone of the apical dendrites of the pyramidal neurons. It was noted that the focal activity of the young immunized animals is characterized by greater maturity as compared with the age norm. A conclusion is drawn regarding the different primary localization of the targets of the neuroimmune effect when antigens of different brain structures are used, namely hippocampus versus neocortex, and regarding the dependence of the physiological effect of neuroimmunization on the degree of maturity of the target structure.

Aging↗

Mast cells in neuroimmune function: neurotoxicological and neuropharmacological perspectives.

Mast cells are located in close proximity to neurons in the peripheral and central nervous systems, suggesting a functional role in normal and aberrant neurodegenerative states. They also possess many of the features of neurons, in terms of monoaminergic systems, responsiveness to neurotrophins and neuropeptides and the ability to synthesise and release bioactive neurotrophic factors. Mast cells are able to secrete an array of potent mediators which may orchestrate neuroinflammation and affect the integrity of the blood-brain barrier. The 'cross-talk' between mast cells, lymphocytes, neurons and glia constitutes a neuroimmune axis which is implicated in a range of neurodegenerative diseases with an inflammatory and/or autoimmune component, such as multiple sclerosis and Alzheimer's disease. Mast cells appear to make an important contribution to developing, mature and degenerating nervous systems and this should now be recognised when assessing the neurotoxic potential of xenobiotics.

Animals↗

Spontaneous regression of cancer: new insights.

Suppression of oncogene expression and of host- or tumour-expressed growth factors and receptors may precipitate spontaneous regression or dormancy in human cancer. Loss of oncogenes necessary for progressive proliferation can lead to differentiation changes. Both natural factors and chemical agents can trigger such a change, and of the naturally occurring agents, growth factors and immunological factors have been most studied. We may find new clues to biological methods of prolonging arrest of cancer, by looking for cytogenetic abnormalities, alterations in oncogene expression and immunocytological composition, in patients showing prolonged dormancy of cancer.

Cell Differentiation↗

Participation of opiate delta-receptors in immunomodulation.

The activation of the opiate delta-receptors by the highly specific agonist DSLET evokes an immunoinhibitory effect in CBA mice which disappears with preliminary blockade of S2 serotonin receptors by cyproheptadine. The blockade of delta-receptors by the antagonist ICI 174,864 leads to stimulation of the immune response, which is tested on the basis of the number of rosette-forming cells. Neither stimulation nor suppression of immunogenesis are manifested in animals with a transsected hypophyseal stalk; this suggests the central action of the opioids. The increase in the immune response obtained with the administration of ICI 174,864 is associated with the dopaminergic system, since it is prevented by haloperidol. It was demonstrated that the thymus participates in the immune-stimulating influence of ICI 174,864.

Analgesics↗