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Nervous system-immune system communication.

This essay is based on the premise that certain individuals may have a biologically determined propensity to respond to infection that is manifested by the development of disease such as chronic fatigue syndrome; the sequence of events that leads to this response involves the immune system. Biochemical pathways between the immune and nervous systems are reviewed, and the role of various products in the systemic circulation, including interleukin-1, pituitary hormone, and catecholamines, is highlighted. This premise could be tested by measuring levels of these substances in carefully selected patients and controls.

Animals

The brain and the immune system: an intact immune system is essential for the manifestation of withdrawal in opiate addicted rats.

Gamma irradiation (500 rad) is often used to suppress the immune system in mice, rats and man. Recently, it was shown that irradiation prior to chronic morphine treatment, dramatically reduces the severity of naloxone-precipitated withdrawal in morphine-dependent animals. In the present study adoptive transfer of 2-6 x 10(8) splenocytes to irradiated rats prior to chronic morphine treatment restored the severity of all withdrawal signs precipitated by naloxone. In contrast, adoptive transfer of fractionated splenocyte subpopulations only partially restored withdrawal severity; and transfer of irradiated splenocytes, red blood cells or diluted numbers of normal splenocytes did not have any observed restorative effect. These findings suggest that specific cellular activities or factors derived from lymphoid cells are required for the expression of opiate withdrawal.

Animals

The immune system and intravenous administration of immune globulin. Part I, The immune system.

Interest in the immune response has greatly increased, mostly because of the discovery of the AIDS virus. An understanding of the basic function of the normal human immune system is vital knowledge for today's nurse. Part 1 of this article describes normal immune response as well as abnormal immune system function, and correlates this information with the clinical picture of the patient.

Antibody Formation

[Recent perceptions on the development, assembly and function of the immune system].

The immune system developed through many stages during evolution. It is fascinating that none of the diverse defense mechanisms vanished in such a long period of nearly 3.5 billion years. They still function in the integrated immune system. The barrier system can be compared to the immune system. The immune system itself is subdivided in antigen-independent, paraspecific (primitive immune system) and antigen specific (specific immune system), restricted immune reactions. The role and use of the phylogenetically older, paraspecific mechanisms, that will react immediately after antigen exposure, are discussed in detail. The immune system is not autonomous. It is closely linked to the hormonal, circulatory, metabolic and nervous systems. Its function is comparable to a sensory organ. Psychoneuroimmunology as a new discipline is mentioned. Immunity and paramunity are not seen as opposing phenomena but are linked in their functions. The terminology of immunology is discussed.

Animals

[Interaction between the central nervous system and the immune system--review].

Results of research within the last years suggest that although the immune system has an autonomous regulation, it is nevertheless subject to control and regulation by the central nervous system. Likewise the central nervous system receives many informations from the immune system. There is a complete regulatory circle between both systems. Disturbances in one system cause changes in the other system. The mechanisms of mutual influences are described and their importance in the pathogenesis of diseases and disturbances of functions are discussed.

Central Nervous System

Origin and evolution of the vertebrate immune system.

The immune system is a complex evolutionary unit and it would be simplistic to conclude that the immune systems of all primitive vertebrates are primitive. Because of the large number of elements involved, many evolutionary events must have taken place, some of them neutral, some of them selected, to constitute the systems that we are looking at towards the end of the 20th century. All these systems have perhaps evolved beyond the apparent evolutionary state of the species in which they are found. They have been modulated by factors linked not only to the internal evolution of their elementary genes, but also by coevolution with factors in the internal environment, such as cellular constraints, metabolism, mode of reproduction and progeny size. It seems that good inventions are long lasting, which is the reason why some elements of the invertebrate immune system can be found with similar functions in vertebrates (defensins). It is also the reason why Ig domains have been exploited in so many ways, whether for the immune system or not. Again, they had an evolution of their own. The comparative study of the immune systems carried out on the occasion of this phylogenetic survey shows a world particularly dynamic and diverse. The comparisons between the solutions chosen by the various phyla of the animal kingdom, or closer to us by the various classes of vertebrates, allow us to distinguish the essential features of the immune system. From this viewpoint, this approach is not only of phylogenetic interest, but also has an applied aspect. Increasing our knowledge in this area could help suggest solutions to clinicians when they are faced with deficiencies and abnormalities in the immune system of man.

Animals

Intra-articular immunization induces strong systemic immune response in humans.

There is no information available about immunological interactions between the synovial tissue compartment and systemic immunity in health and in disease. The aim of the present study was to evaluate effects of intra-articular immunization on the systemic immune responses in humans. Control subjects were immunized with the same dose of immunogen subcutaneously. Peripheral blood lymphocytes were analysed by spot-ELISA with respect to numbers of immunoglobulin-producing cells and antigen-specific antibody-secreting cells before and 1 week after immunization. Serum and salivary antibody levels were measured by an ELISA before and 14 days after the antigenic exposure. In addition, serum levels of interleukin-6 (IL-6) were analysed before and after immunization. The results indicate that the influenza virus antigen deposited in the joint space induces strong systemic antibody response of IgG, IgA and IgM classes. This response is significantly higher (P less than 0.05) than that of control subjects immunized subcutaneously. In contrast, no significant differences were detected between intra-articularly and subcutaneously immunized subjects with respect to mucosal immune responses. Increased serum levels of IL-6 were observed 1-2 weeks after the vaccination in both experimental groups. We conclude that human joints possess very efficient antigen-presenting properties enhancing systemic B cell reactivity.

Adult

Secretory immune system of the female reproductive tract. II. Local immune system in normal and infected fallopian tube.

The existence of a secretory immune system in the female genital tract has been demonstrated by the predominance of immunoglobulin (Ig)A-producing plasma cells in human fallopian tube, uterine cervix, and vagina. Epithelium lining fallopian tubes expresses a receptor for IgA, secretory component (SC), and thus resembles other secretory tissues such as intestine, mammary, lacrimal, and salivary glands. The present study extends the characterization of the local immune system in the fallopian tube and assesses its response to infection. We examined normal and infected fallopian tubes from surgical specimens, obtained at tubal ligation and abdominal hysterectomy, for the presence of Ig-producing cells, T cells, and natural killer cells. All tubular segments contained a predominance of IgA plasma cells in the subepithelial lamina propria. The epithelial cells were strongly positive for SC. Luminal contents stained positively for IgA, SC, and J chain, suggesting that this material contained secretory IgA. Submucosal plasma cells of IgM and IgG classes were less frequent than IgA. T cells were present in numbers approximately twofold greater than plasma cells in normal fallopian tubes. T-suppressor (CD8+) cells, which may function in the induction of immune tolerance, were present in the intraepithelial spaces. Infected segments of fallopian tubes demonstrated six- to tenfold increased numbers of plasma cells of all classes. These data suggest that a local immune system is functioning in the human fallopian tube and may provide a first line of defense against tubal infection and the prevention of tubal factor infertility.

Epithelium

How human immunodeficiency virus ravages the immune system.

The immune system of individuals infected with human immunodeficiency virus is affected in two distinct ways: by loss of CD4+ cells and by loss of T-helper-cell function. Neither of these processes is yet fully understood. Research during 1991 that investigated the interaction between human immunodeficiency virus and the immune system has raised as many questions as it answered. Nevertheless, many of the issues raised are relevant to mechanisms responsible for the ravaging of the immune system by human immunodeficiency virus.

Acquired Immunodeficiency Syndrome

[Psychoimmunology. II. The neuroendocrine system and the immune system in autism and schizophrenia].

In this paper the Authors report on the immunologic alterations in two psychiatric disease: schizophrenia and infantile autism. While a lot of researches have been concluded on the immunologic alterations in schizophrenia, only a few data on infantile autism are available. Based on data from international literature the Authors advance some hypotheses on the role possibly played by the immune system in the pathogenesis of schizophrenia and infantile autism.

Autistic Disorder

[The nervous system and the immune system: the role of morphine and opioid peptides in the function of neutrophilic granulocytes].

Inhibition of human granulocyte chemotaxis towards casein was observed in the presence of mu and k receptor agonist, which per se exhibits chemokinetic activity. Naloxone was found to prevent both the opioid and opioid unrelated increase of granulocyte migration. Although opioid agonists with different receptors specificity were capable of strongly modifying human granulocyte migration, no conclusion can be drawn on the role of opioid receptors in regulating migration activity. The effects of morphine and opioid peptide on neutrophil aggregation and ATOP release were studied. Inhibition of human granulocyte aggregation and ATP release was observed in the presence of morphine in a naloxone stereoselective manner, whereas the opioid peptides were ineffective. The effect of DAGO, DADL and dynorphin 1-9 on granulocyte aggregation and ATP release were also evaluated, but these opioid peptides are unable to modify neutrophil function. Our studies confirm the role of mu receptors on modulation of polymorphonuclear granulocyte function and suggest a key role of opioid peptides in the regulation of some immune system functions. In comparative studies Ca++ (A 23,187) and dynorphin 1-9, per se, induced stimulation of arachidonic acid metabolites from granulocytes. In this regard dynorphin 1-9 may function as a mediator between the central nervous system and immunity.

Adenosine Triphosphate

Intragonadal regulation of immune system functions.

Immune responses within the mammalian gonads, and in particular the testis, are deficient in spite of adequate lymphatic drainage and the presence of lymphocytes and MHC II+ macrophages. There is considerable evidence from in vivo and in vitro studies that this 'suppression' of the immune system may be due, at least in part, to localized inhibition or regulation of normal lymphocyte and/or macrophage functions within the gonads. In the testis, both steroidal and non-steroidal products of the Leydig cells, including androgens, endorphins, and inhibin-related proteins, have been implicated in mediating this activity. In turn, a number of immune cell cytokines affect steroidogenic cell function in vitro. The studies described in this paper indicated that [3H]-thymidine incorporation by adult rat thymocytes in vitro was inhibited by conditioned medium collected from short-term incubations of Percoll-purified adult rat Leydig cells, but stimulated by testicular interstitial fluid and by conditioned medium collected from short-term incubations of adult rat seminiferous tubules. The factors responsible for these effects on thymocyte function appeared to be of large molecular weight, as they were retained by ultrafiltration membranes with exclusion limits of 10,000 or 30,000 daltons. It is hypothesized that an 'immunosuppressive' mechanism, principally mediated by non-steroidal factors secreted by the steroidogenic cells of the gonadal interstitial tissue, exists within the gonads in order to prevent activation of the immune system by germ cell antigens and growth factors associated with germ cell proliferation and differentiation. This mechanism probably acts in parallel with normal antigen-specific tolerance mechanisms operating at the gonadal level. As immune responses to germ cells are believed to be a significant causative factor in infertility, particularly in men, this represents an important area for further study.

Animals