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PubMed1987

Zinc deficiency and immune function.

Deficiency in zinc, an essential trace element, is a frequent human dietary problem in the United States and is also associated with such disease states as alcoholism, renal disease, burns, gastrointestinal tract disorders, and acrodermatitis enteropathica. Skin lesions and poor wound healing are observed in severe forms of the deficiency. However, modest deficits in zinc cause lymphopenia and reduced immune capacity among affected humans. With the mouse used as a model because it has an immune system analogues to that of humans, the effects of zinc deficiency on immune function have been well characterized. A suboptimal intake of zinc causes marked atrophy of the thymus, a 50% reduction in leukocytes, a rise in corticosterone levels, and a 40% to 70% reduction in antibody-mediated, cell-mediated, and delayed-type hypersensitivity responses.

Animals↗
PubMed1997

Effectiveness of a short-term group psychotherapy program on endocrine and immune function in breast cancer patients: an exploratory study.

Cancer patients who had been treated for early stage breast cancer and were diagnosed with either positive axillary lymph nodes or distant metastases were randomly assigned to either a 13-week experiential-existential group psychotherapy (EEGP) program or a waiting list control (WLC) condition. Endocrine and immune measures were obtained before and after the intervention period. The findings of this study are that, after the 13 weeks of the experiment, patients in the EEGP group showed lower levels of plasma cortisol and lower levels of prolactin as well as lower percentages of natural killer cells, CD8 cells, and CD4 cells in addition to a lower proliferative response to pokeweed mitogen than patients in the WLC group. Importantly, this was only found in those breast cancer patients presenting relatively high endocrine and immune baseline levels, suggesting that the patients' profile with regard to endocrine and immune function at the start of a program can have an important effect. If replicated on a larger scale, the current results may be relevant for the treatment of breast cancer.

Adrenocorticotropic Hormone↗
PubMed2005

Alterations in neutrophil (PMN) free intracellular alpha-keto acid profiles and immune functions induced by L-alanyl-L-glutamine, arginine or taurine.

The objective of this study was to determine the dose as well as duration of exposure-dependent effects of L-alanyl-L-glutamine, arginine or taurine on polymorphonuclear neutrophil (PMN) free alpha-keto acid profiles and, in a parallel study, on PMN immune functions. Exogenous L-alanyl-L-glutamine significantly increased PMN alpha-ketoglutarate, pyruvate PMN superoxide anion (O2-) generation, hydrogen peroxide (H2O2) formation and released myeloperoxidase (MPO) activity. Arginine also led to significant increases in alpha-ketoglutarate, pyruvate, MPO release and H2O2 generation. Formation of O2- on the other hand was decreased by arginine. Incubation with taurine resulted in lower intracellular pyruvate and alpha-ketobutyrate levels, decreased O2- and H2O2 formation and a concomitant significantly increased MPO activity. We therefore believe that considerable changes in PMN free-alpha-keto-acid profiles, induced for example by L-alanyl-L-glutamine, arginine or taurine, may be one of the determinants in cell nutrition that considerably modulates the immunological competence of PMN.

Adult↗
PubMed1996

Allogeneic bone marrow transplantation can restore CD4+ T-lymphocyte count and immune function in idiopathic CD4+ T-lymphocytopenia.

CD4+ T-lymphocytopenia in the absence of HIV infection is a heterogeneous disorder of unknown cause. Here we report a patient with idiopathic CD4+ T-lymphocytopenia, presenting with an opportunistic Rhodococcus equi infection. When aplastic anemia developed subsequently, allogeneic bone marrow transplantation was performed. Complete restoration of immune function was observed. We conclude that allogeneic bone marrow transplantation presents a potentially curative therapy for CD4+ T-lymphocytopenia.

Actinomycetales Infections↗
PubMed1985

Effect of social support on stress-related changes in cholesterol level, uric acid level, and immune function in an elderly sample.

Strong social support systems, which in epidemiologic studies are associated with decreased morbidity and mortality, have been hypothesized to mitigate the harmful effects of stressful stimuli on the individual. The authors found that, among 256 healthy elderly adults, individuals with good social support systems tended to have lower serum cholesterol and uric acid levels and higher indices of immune function; these correlations were independent of age, body mass, tobacco use, alcohol intake, and degree of perceived psychological distress. Thus, social support systems may intervene between the stressful stimulus and the physiologic response to that stimulus.

Age Factors↗
PubMed2006

Sustained thymopoiesis and improvement in functional immunity induced by exogenous KGF administration in murine models of aging.

Age-related thymopoietic insufficiency has been proposed to be related to either defects in lymphohematopoietic progenitors or the thymic microenvironment. In this study, we examined whether keratinocyte growth factor (KGF), an epithelial cell-specific growth factor, could increase thymopoietic capacity in aged mice by restoration of the function of thymic epithelial cells (TECs). The thymic cellularity in KGF-treated aged mice increased about 4-fold compared to placebo-treated mice, resulting in an equivalent thymic cellularity to young mice. Enhanced thymopoiesis was maintained for about 2 months after a single course of KGF, and sustained improvement was achieved by administration of monthly courses of KGF. With the enhanced thymopoiesis after KGF treatment, the number of naive CD4 T cells in the periphery and T-cell-dependent antibody production improved in aged mice. KGF induced increased numbers of TECs and intrathymic interleukin-7 (IL-7) production and reorganization of cortical and medullary architecture. Furthermore, KGF enhanced thymopoiesis and normalized TEC organization in klotho (kl/kl) mice, a model of premature degeneration and aging, which displays thymopoietic defects. The result suggests that TEC damage is pathophysiologically important in thymic aging, and KGF therapy may be clinically useful in improving thymopoiesis and immune function in the elderly.

Aging↗
PubMed2001

Nutritional factors and immune functions of gut epithelium.

The intestinal epithelium acts as a barrier to the external environment contained within the lumen of the gut. It also transports solutes for nutrition and for immunological surveillance. The present review develops the hypothesis that changes in diet, through the composition of the lumen environment, alter the expression of genes in the epithelium. These genes include those that encode for proteins that signal to the mucosal immune system. Directly changing the expression of signalling molecules in the intestinal epithelium using transgenic techniques alters immune function. For example, up regulation of the chemokine macrophage inflammatory protein-2 increases neutrophil recruitment. Furthermore, lumen molecules such as short-chain fatty acids regulate chemokine expression by epithelial cells. By this means, the epithelium acts as a transducing monolayer signalling between the contents of the intestine and the mucosal immune system.

Animals↗
PubMed2006

Pineal-dependent and -independent effects of photoperiod on immune function in Siberian hamsters (Phodopus sungorus).

Siberian hamsters (Phodopus sungorus) exhibit reproductive and immunological responses to photoperiod. Short (<10-h light/day) days induce gonadal atrophy, increase leukocyte concentrations, and attenuate thermoregulatory and behavioral responses to infection. Whereas hamster reproductive responses to photoperiod are dependent on pineal melatonin secretion, the role of the pineal in short-day induced changes in immune function is not fully understood. To examine this, adult hamsters were pinealectomized (PINx) or sham-PINx, and transferred to short days (9-h light/day; SD) or kept in their natal long-day (15-h light/day; LD) photoperiod. Intact and PINx hamsters housed in LD maintained large testes over the next 12 weeks; sham-PINx hamsters exhibited gonadal regression in SD, and PINx abolished this effect. Among pineal-intact hamsters, blood samples revealed increases in leukocyte, lymphocyte, CD62L+ lymphocyte, and T cell counts in SD relative to LD; PINx did not affect leukocyte numbers in LD hamsters, but abolished the SD increase in these measures. Hamsters were then treated with bacterial lipopolysaccharide (LPS), which induced thermoregulatory (fever), behavioral (anorexia, reductions in nest building), and somatic (weight loss) sickness responses in all groups. Among pineal-intact hamsters, febrile and behavioral responses to LPS were attenuated in SD relative to LD. PINx did not affect sickness responses to LPS in LD hamsters, but abolished the ameliorating effects of SD on behavioral responses to LPS. Surprisingly, PINx failed to abolish the effect of SD on fever. In common with the reproductive system, PINx induces the LD phenotype in most aspects of the immune system. The pineal gland is required for photoperiodic regulation of circulating leukocytes and neural-immune interactions that mediate select aspects of sickness behaviors.

Animals↗
PubMed1982

Effects of shipping on the immune function in mice.

The effect of shipping stress on immunologic functions was examined in mice. The mice were shipped either by truck or by plane, 2 of the most common modes for transport of animals. While mice were in transit, temperature fluctuations and light intensity were monitored. The foot pad test, hemagglutination assay, and plaque-forming cell assay were used to measure immunologic function. Corticosterone concentrations were quantitated with a competitive protein-binding technique. Regardless of the method of shipment, corticosterone values in the mice were markedly increased at arrival and remained at the high value for a 48-hour period. Immune-function assays were significantly lessened in the mice at arrival, but returned to base line within 48 hours, indicating that a minimum 48-hour stabilization period is required for all new arrivals.

Animal Husbandry↗
PubMed2000

Randomized safety studies of intravenous perflubron emulsion. II. Effects on immune function in healthy volunteers.

Particle size distribution is a major determinant of particle clearance by the mononuclear phagocytic system and the potential for concomitant activation of resident macrophages. To test the safety of a second-generation perflubron-based emulsion (60% perfluorocarbon [PFC] wt/vol; Oxygent [Alliance Pharmaceutical Corp., San Diego, CA]) with a small mean particle size, two parallel, randomized, double-blinded, placebo-controlled studies were conducted in 48 healthy volunteers (n = 24 per study). The study described herein focuses on safety concerning immune function. The primary endpoint was defined prospectively as delayed hypersensitivity skin test responses with lymphocyte proliferative responses to mitogenic stimulation providing a secondary measure for changes in cell-mediated immunity. Subjects received either perflubron emulsion IV (1.2 g PFC/kg or 1.8 g PFC/kg) or saline (3 mL/kg) control. Perflubron emulsion had no effect on delayed hypersensitivity skin reactions, lymphocyte proliferative potential, circulating immunoglobulins, complement activation, or plasma levels of the inflammatory cytokines, tumor necrosis factor-alpha, interleukin-1 alpha, and interleukin-1 beta. Perflubron emulsion was generally well tolerated, although there was a dose-dependent increase in minor flu-like symptoms in the perflubron treatment groups at 24 h after dosing. Increased serum levels of interleukin-6 were observed in those subjects exhibiting febrile responses. The clinical safety profile of perflubron emulsion supports its continued investigation as a temporary oxygen carrier in surgical patients to reduce exposure to allogeneic blood transfusion.

Adolescent↗
PubMed1994

HIV infection, exercise, and immune function.

Decreased physical endurance is viewed by both HIV-infected people and their primary nurses as a major healthcare problem. There is a widespread belief among HIV-infected people that the way to improve their endurance is through exercise. Yet healthcare providers are divided about the role of exercise. This paper presents an overview of decreased endurance as a major problem in this population, with a review of the literature on exercise in healthy and chronically-ill populations, including those with HIV infection, and its effect on immune function.

Adolescent↗
PubMed1991

Immune function and anti-HTLV-I/II status in anti-HIV-1-negative intravenous drug users receiving methadone.

PURPOSE: The study objective was to evaluate the effects of long-term methadone use and human T-cell leukemia virus (HTLV) types I and II seropositivity on the distribution of lymphocyte subsets and on lymphocyte function as measured in vitro in intravenous drug users seronegative for human immunodeficiency virus type 1 (HIV-1). PATIENTS AND METHODS: Anti-HIV-1-negative intravenous drug users receiving methadone maintenance therapy (n = 24) were studied in a Veterans Administration drug abuse treatment center. These subjects were compared to 38 age- and sex-matched control subjects who did not abuse drugs. HIV-1 and HTLV serostatus was determined by repetitive enzyme-linked immunosorbent assay and confirmed by immunoblot. Lymphocyte subsets were determined by two-color flow cytometry. Lymphocyte function was measured by proliferative response to plant mitogens and by natural killer (NK) cell-mediated cytotoxicity to a tumor cell target. RESULTS: Significant differences were seen in lymphocyte phenotype in the methadone-treated group, with elevations in the T-cell helper subset CD4+CD26+; in CD8 and CD8+I2+ cells, suppressor/cytotoxic T lymphocytes, and activated suppressor/cytotoxic T cells; and in CD2+CD26+ cells and activated total T lymphocytes. Lymphocyte function was suppressed in the methadone group, with poor responses to pokeweed mitogen and phytohemagglutinin in culture. Moreover, NK-cell cytotoxicity was significantly reduced in the methadone group. None of these immunologic differences were attributable to HTLV serostatus. CONCLUSION: The immune abnormalities seen suggest that a clinically significant degree of immune impairment exists in methadone-treated intravenous drug users. However, these abnormalities could not be explained by the presence of other retroviruses in this HIV-1-negative study group, as there was no significant difference in immune function when HTLV-seropositive patients were compared to HTLV-seronegative subjects treated with methadone.

Adult↗
PubMed1988

Humoral immune function in pediatric patients treated with autologous bone marrow transplantation for B cell non-Hodgkin's lymphoma. The influence of ex vivo marrow decontamination with anti-Y 29/55 monoclonal antibody and complement.

Elimination of neoplastic B cell populations from autologous bone marrow grafts also removes normal B lymphocytes. This is potentially hazardous for the reconstitution of the immune system in patients undergoing high-dose chemotherapy and total body irradiation followed by autologous marrow rescue. Five pediatric patients with B cell non-Hodgkin's lymphoma in first remission undergoing such a regimen were studied. They received bone marrow pretreated with anti-Y 29/55 monoclonal antibody and complement. B and T lymphocyte subpopulations reached normal levels within 6 months after autologous bone marrow transplantation (ABMT), and serum immunoglobulin levels became normal within 4 to 9 months. Vaccination with diphtheria and tetanus toxoid, trivalent poliomyelitis vaccine of the Salk type, and pneumococcal capsular antigens (38 to 54 months after transplantation) gave rise to specific antibody production. ABO isoagglutinins could be demonstrated in all patients. The response pattern was similar to that of patients who received unmanipulated autologous bone marrow. It is concluded that ex vivo anti-Y 29/55 depletion of the marrow graft does not induce relevant disturbances of humoral immune functions.

Adolescent↗
PubMed2002

Photoperiodic effects on endocrine and immune function in cattle.

Photoperiod is the most common environmental factor monitored by animals to alter long-term physiological processes, particularly reproduction. As cattle are not strict seasonal breeders, the influence of photoperiod on cattle has been studied less extensively than in other large mammals, but the lack of effect of daylength on reproduction enhances the utility of the bovine model in examining the effect of this factor on growth, lactation and immune function. In cattle, as in other species, increasing exposure to light reduces the duration of melatonin secretion. A long day pattern of melatonin secretion increases circulating prolactin and insulin-like growth factor I (IGF-I) concentrations and these endocrine shifts are consistent with observed effects on lactation, and body growth and composition in cattle. In addition, we have observed that long day photoperiod decreases the metabolic perturbations encountered in response to the immune challenge with lipopolysaccharide. Although circulating hormones, such as prolactin and IGF-I, are certainly involved in these responses, receptor-mediated effects of photoperiod are also active. Currently, our focus is on photoperiod-induced shifts in receptor expression in the mammary gland, liver and leucocytes, as target tissues for the photoneuroendocrine response.

Animals↗
PubMed1979

Effects of the obese (ob/ob) genotype on spleen cell immune function.

Spleen cells from mice homozygous for the obese (ob) mutation killed DBA/2 mastocytoma target cells less well than spleen cells from lean littermates or unrelated age-and sex-matched controls of the same strain. Killing was impaired only when the attacker cells were primed in vivo, not following in vitro priming. Hence the effect of the ob/ob genotype is not to produce an irreversible functional change in the lymphocyte, but rather to produce an environment in which lymphocytes are less able to react to priming antigen. Not only were the spleen cells of in vivo primed obese mice less active than those of lean controls, but also their number per spleen was significantly decreased. Such a quantitive difference was no longer found in adrenalectomised animals, but the qualitative difference in spleen cell cytotoxic activity still occurred. This suggests that adrenocortical hyperfunction may affect immune function in obese mice, without necessarily being the only factor in the in vivo environment of obese mouse spleen cells capable of depressing cellular immune reactivity.

Adrenalectomy↗
PubMed1985

Hemopoiesis and immune functions in dogs following fetal liver transplantation.

Ten beagles were exposed to total body X-irradiation (3 X 6 Gy) and rescued with cryopreserved fetal liver cells from DLA-identical siblings obtained around the 52nd day of gestation. Grafts contained 0.2-1.6 X 10(8) mononuclear cells/kg and 0.9-19.8 X 10(4) granulocyte-macrophage progenitor cells/kg. Hemopoiesis and immune functions were followed for up to one year after fetal liver transplantation (FLT). There was a prompt engraftment in all recipients. Bone marrow metaphases were always of donor origin, whereas some host lymphocytes circulated for 2-3 months. Blood granulocytes and monocytes rose to pre-treatment levels within 2-3 weeks of FLT and platelets and erythrocytes were normal within 3-4 and 5-6 weeks, respectively. The relative incidence of bone marrow CFU-GM was normal by day 14 and the absolute numbers of circulating CFU-GM remained elevated for one year after day 14. Blood lymphocytes reached control numbers between days 35 and 101 with a faster B cell than T cell recovery. Their response to mitogen stimulation was normal by day 75, while the mixed lymphocyte reaction tended to be reduced for one year. Serum levels of IgM (day 35) and IgG (day 49) recovered earlier than IgA levels (day 270). Thus, cryopreserved canine fetal liver cells can restore hemopoiesis and immunocompetence with considerable rapidity in histocompatible, adult siblings pre-treated with total body irradiation, and, since they lack mature T cells, may be used to analyze effector mechanisms that mediate rejection of T cell-depleted allografts under less favourable conditions.

Animals↗
PubMed2003

Zinc-altered immune function.

Zinc is known to be essential for all highly proliferating cells in the human body, especially the immune system. A variety of in vivo and in vitro effects of zinc on immune cells mainly depend on the zinc concentration. All kinds of immune cells show decreased function after zinc depletion. In monocytes, all functions are impaired, whereas in natural killer cells, cytotoxicity is decreased, and in neutrophil granulocytes, phagocytosis is reduced. The normal functions of T cells are impaired, but autoreactivity and alloreactivity are increased. B cells undergo apoptosis. Impaired immune functions due to zinc deficiency are shown to be reversed by an adequate zinc supplementation, which must be adapted to the actual requirements of the patient. High dosages of zinc evoke negative effects on immune cells and show alterations that are similar to those observed with zinc deficiency. Furthermore, when peripheral blood mononuclear cells are incubated with zinc in vitro, the release of cytokines such as interleukins (IL)-1 and -6, tumor necrosis factor-alpha, soluble IL-2R and interferon-gamma is induced. In a concentration of 100 micro mol/L, zinc suppresses natural killer cell killing and T-cell functions whereas monocytes are activated directly, and in a concentration of 500 micro mol/L, zinc evokes a direct chemotactic activation of neutrophil granulocytes. All of these effects are discussed in this short overview.

Dietary Supplements↗
PubMed1997

Regulation of immune functions in rat splenocytes after acute and chronic in vivo treatment with CP-55,940, a synthetic cannabinoid compound.

Changes in mitogen-induced splenocyte proliferation and NK activity were evaluated after acute (1 h) and chronic (6 d) in vivo treatment of rats with the synthetic cannabinoid compound CP-55,940. At a dose of 0.4 mg/kg i.p. it significantly inhibited the splenocyte proliferative response to PHA and NK activity but half this dose (0.2 mg/kg) had no effect on immune responses. Pretreatment of rats with the cannabinoid receptor CB1 antagonist SR141716A did not antagonize the CP-55,940-induced immunosuppression, excluding the activation of this receptor subtype in the mediation of this effect. When immune function studies were done on rats tolerant to CP-55,940-induced analgesia, full tolerance also developed for the inhibition of splenocyte proliferation and NK activity. The data provided indicate that CB1 cannabinoid receptors are not involved in mediating the acute and chronic effects of cannabinoids on the immune system and suggest a possible implication of CB2 receptor although other modalities of CP-55,940 action can not be ruled out.

Animals↗