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At least 1,117 records · Page 62Linked to original sources
PubMed2003

[Effect of astragalus injection on immune function in patients with congestive heart failure].

OBJECTIVE: To study the effect of Astragalus Injection (AI) on the humoral immunity (IgG, IgA and IgM), cellular immunity (T-lymphocyte subsets) and soluble interleukin-2 receptor (sIL-2R) in patients with congestive heart failure (CHF). METHODS: Sixty-two in-patients with CHF, whose heart function belonged to NYHA grade II-IV, were randomly divided into two groups. The treated group was treated with AI 30 ml (equivalent to 60 g crude drug), and the control group was treated by nitroglycerine injection 10 mg, the drugs were administered respectively by adding in 5% glucose solution 500 ml for intravenous dripping, once a day, 20 days as one therapeutic course. Venous blood from cubital vein was collected before and after treatment to detect the IgG, IgA, IgM, T-lymphocyte subsets and sIL-2R, and the clinical effect of treatment was evaluated. RESULTS: The clinical heart function markedly improved rate and total effective rate in the treated group was 25.8% and 74.2% respectively, significantly better than those in the control group respectively (P < 0.05 or P < 0.01), the left ventricular ejecting fraction (LVEF) and end syctolic volume (ESV) were improved in both groups (P < 0.05, P < 0.01), and the improvement in the treated group was superior to that in the control group (P < 0.05). In the treated group after treatment, the CD4 level and CD4/CD8 ratio increased (P < 0.05), levels of sIL-2R, IgG and IgA lowered (P < 0.05) significantly, while those in the control group were not changed significantly (P > 0.05). CONCLUSION: AI could improve the immune function of CHF patients, and can be taken as an important auxiliary treatment for CHF.

Adjuvants, Immunologic↗
PubMed1997

Effects of growth hormone and insulin-like growth factor I on T- and B-lymphocytes and immune function.

The concept of a neuro-endocrine-immune axis was proposed more than 50 years ago. Growth hormone (GH), a central component of this axis has many functions at both a molecular and cellular level, including thymocyte proliferation, stimulation of the cytotoxic activity of natural killer cells and induction of lymphocyte proliferation. Binding of GH to its receptors on lymphocytes stimulates the production of insulin-like growth factor I (IGF-I), which mediates the effects of GH on cell proliferation. Other effects of GH on the immune system appear to be direct, such as priming monocytes for enhanced production of hydrogen peroxide in response to phorbol esters, and stimulating neutrophils to secrete superoxide anions associated with enhanced phagocytic activity. Many of the effects of GH are shared by IGF-I. Despite these observations, and the fact that GH is produced and secreted in immunological tissues such as the thymus and spleen, immune deficiency is not characteristic of GH deficiency in humans. The question remains as to whether GH and IGF-I could be used as immunotherapy. Currently, both agents have been used in adults to diminish wasting due to acquired immunodeficiency syndrome, and GH has been shown to stimulate CD8+ cell counts. However, they had little impact on CD4+ cell counts, which may be due to IGF-I and GH resistance in these individuals. The use of GH and IGF-I as immunotherapies merits further study.

Adult↗
PubMed2003

Lack of effect of foods enriched with plant- or marine-derived n-3 fatty acids on human immune function.

BACKGROUND: Greatly increasing dietary flaxseed oil [rich in the n-3 polyunsaturated fatty acid (PUFA) alpha-linolenic acid (ALA)] or fish oil [rich in the long-chain n-3 PUFAs eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids] can reduce markers of immune cell function. The effects of more modest doses are unclear, and it is not known whether ALA has the same effects as its long-chain derivatives. OBJECTIVE: The objective was to determine the effects of enriching the diet with ALA or EPA+DHA on immune outcomes representing key functions of human neutrophils, monocytes, and lymphocytes. DESIGN: In a placebo-controlled, double-blind, parallel study, 150 healthy men and women aged 25-72 y were randomly assigned to 1 of 5 interventions: placebo (no additional n-3 PUFAs), 4.5 or 9.5 g ALA/d, and 0.77 or 1.7 g EPA+DHA/d for 6 mo. The n-3 PUFAs were provided in 25 g fat spread plus 3 oil capsules. Blood samples were taken at 0, 3, and 6 mo. RESULTS: The fatty acid composition of peripheral blood mononuclear cell phospholipids was significantly different in the groups with higher intakes of ALA or EPA+DHA. The interventions did not alter the percentages of neutrophils or monocytes engaged in phagocytosis of Escherichia coli or in phagocytic activity, the percentages of neutrophils or monocytes undergoing oxidative burst in response to E. coli or phorbol ester, the proliferation of lymphocytes in response to a T cell mitogen, the production of numerous cytokines by monocytes and lymphocytes, or the in vivo delayed-type hypersensitivity response. CONCLUSION: An intake of <or= 9.5 g ALA/d or <or= 1.7 g EPA+DHA/d does not alter the functional activity of neutrophils, monocytes, or lymphocytes, but it changes the fatty acid composition of mononuclear cells.

Adult↗
PubMed2000

Asthma severity, psychophysiological indicators of arousal, and immune function in asthma patients undergoing biofeedback-assisted relaxation.

Asthma is characterized by airway hyper-responsiveness, inflammation, and reversible obstruction. Respiratory tract infection, allergies, air pollution, and psychosocial factors impact the severity and frequency of asthma symptoms. Pharmacotherapy and self-care are the major components in the management of asthma, but behavioral interventions also have the potential to affect asthma morbidity. We conducted a small, randomized controlled study, examining the effects of biofeedback-assisted relaxation in 16 nonsmokers with nonsteroid-dependent mild asthma. Data were collected on asthma symptoms, pulmonary function, indicators of arousal, and cellular immune factors. The trained group evidenced a decrease in forehead muscle tension in comparison to the controls, but no changes in peripheral skin temperature. Decreases in asthma severity and bronchodilator medication usage for the experimental group were observed. Pulmonary function testing revealed a significant difference between groups in FEV1/FVC at posttest, with the E group having a higher ratio than the controls. The cellular immune data showed no significant group differences in total white blood cell or lymphocyte counts, but decreases over time were observed. Significant differences were observed in the numbers of neutrophils and basophils in the trained group compared to controls, which supports the concept of decreased inflammation. Results of delayed-type hypersensitivity skin testing suggested enhanced function, but they were not conclusive. These findings, though limited by size of population, suggest a positive effect of biofeedback-assisted relaxation in young, nonsteroid-dependent asthmatics. The mechanisms underlying linkages between psychological, behavioral, and immune responses in asthma require further study.

Adolescent↗
PubMed2004

The influence of different combinations of gamma-linolenic acid, stearidonic acid and EPA on immune function in healthy young male subjects.

To determine the effects of EPA, stearidonic acid (STA) or gamma-linolenic acid (GLA) on immune outcomes, healthy male subjects consumed one of seven oil blends for 12 weeks. EPA consumption increased the EPA content of peripheral blood mononuclear cells (PBMC). Consumption of GLA (2.0 g/d) in the absence of STA or EPA increased di-homo-GLA content in PBMC. Neither STA nor its derivative 20 : 4n-3 appeared in PBMC when STA (<1.0 g/d) was consumed. However, STA (1.0 g/d), in combination with GLA (0.9 g/d), increased the proportion of EPA in PBMC. None of the treatments altered neutrophil or monocyte phagocytosis or respiratory burst, production of inflammatory cytokines by monocytes, T lymphocyte proliferation or the delayed-type hypersensitivity response. Production of cytokines by T lymphocytes increased in all groups, with no differences among them. The proportion of lymphocytes that were natural killer cells decreased significantly in subjects receiving 2.0 g EPA or GLA/d. There were no other effects on lymphocyte sub-populations. Plasma IgE concentration decreased in most groups, but not in the control group. Plasma IgG2 concentration increased in the EPA group. Thus, EPA or GLA at a dose of 2.0 g/d have little effect on key functions of neutrophils, monocytes and T lymphocytes, although at this dose these fatty acids decrease the number of natural killer cells. At this dose EPA increases IgG2 concentrations. STA can increase immune cell EPA status, but at 1.0 g/d does not affect human immune function.

Adult↗
PubMed1998

Relation between exploratory activity and immune function in aged mice: a preliminary study.

Previous studies show that fast exploration of a T-shaped maze by mature mice may predict an above average longevity. Since the nervous and the immune systems work in a coordinated fashion, and it seems that these two homeostatic systems both influence organismic aging and suffer a senescent decline, we have performed a comparative study of the above behavioral parameter and different functions of three representative immune cells: lymphocytes, macrophages and natural killer (NK) cells obtained from old (76 +/- 1 weeks of age) female OF1-Swiss mice. At 70 weeks of age the mice were divided into a 'fast' and a 'slow' group, containing 100 and 0%, respectively, of animals able to explore the 50 cm-long first arm of the maze in 20 s or less. At 76 +/- 1 weeks of age the animals were sacrificed, the peritoneal cell suspensions were obtained and the immune organs (axillary nodes, spleen and thymus) were isolated. The following leukocyte functions were studied in peritoneal macrophages: adherence to substrate, mobility (spontaneous and chemotaxis), ingestion of particles and superoxide anion production whereas mobility, lymphoproliferative response to the mitogen Con A and NK activity were studied in the immune-organ leukocyte suspensions. The results show that the aged fast mice have better immune functions than the aged slow mice.

Aging↗
PubMed1993

Abnormal immune function in malignant hypertension.

OBJECTIVE: To investigate the extent to which the immune system is influenced in patients with previous malignant hypertension. DESIGN: Twenty-three patients with malignant hypertension (fundus hypertonicus grades III or IV) in the Gothenburg area were studied over a 3-year period. After treatment had been instituted they were investigated to establish the function of the cellular immune system (number of T lymphocytes and the proliferative response to T-cell mitogens), human leucocyte antigens A, B and C and frequency of autoantibodies. METHODS: The numbers of T lymphocytes were quantified as erythrocyte rosettes. Lymphocyte-stimulation tests were carried out using the T-cell mitogens phytohaemagglutinin and concanavalin-A. Autoantibodies were determined with immunoassay techniques and leucocyte A, B and C antigens with a lymphocytotoxicity test. RESULTS: The frequency of T lymphocytes and their baseline thymidine incorporation were significantly depressed in patients with previously malignant hypertension compared with control subjects. The group with malignant hypertension also had a decreased proliferative response to concanavalin-A but not to phytohaemagglutinin, and they had an increased frequency of antinuclear antibodies. Human leucocyte antigen B15 tended to occur more frequently in patients with malignant and non-malignant hypertension than in control subjects, especially if a family history of hypertension was taken into consideration. CONCLUSION: The results from the present study indicate that immune mechanisms are involved in malignant hypertension, either secondary to the vascular damage or as a primary abnormality.

Antibody Formation↗
PubMed2004

Non-immune functions of MHC class I glycoproteins in normal and malignant cells.

MHC class I glycoproteins play a pivotal role in the regulation of immune responses by presenting antigenic peptides to cytotoxic T lymphocytes and by regulating cytolytic activities of natural killer cells. Cells originating in malignant tumours are often characterized by a profound immune escape phenotype. This phenotype is frequently associated with alterations in MHC class I-related antigen processing and presentation that enable tumours to escape immune surveillance. However, it now becomes clear that MHC class I molecules do not only provide a mechanistic framework for the presentation of antigenic peptides but, rather, possess broader biological functions due to their ability to regulate cell-to-cell communication and receptor-mediated trans-membrane signal transduction. In the present review we made an attempt to reevaluate the significance of an altered MHC class I phenotype for tumour progression in view of the current state of knowledge concerning the aforementioned non-immune functions performed by these membrane glycoproteins.

Animals↗
PubMed1997

Effect of antioxidative vitamins on immune function with clinical applications.

Infection and trauma cause inflammatory stress in patients. Tissue damage, enhanced inflammatory mediator production and suppressed lymphocyte function may occur as a consequence. The antioxidative vitamins, ascorbic acid and the tocopherols, are important not only for limiting tissue damage but also in preventing increased cytokine production which is a consequence of excessive activation of NF kappa B. Glutathione is a major endogenous antioxidant and is important for lymphocyte replication. Two vitamins, vitamin B6 and riboflavin participate in the maintainance of glutathione status. The former vitamin acts as a cofactor in the synthesis of cysteine (the rate limiting precursor for glutathione biosynthesis) and the latter vitamin is a cofactor for glutathione reductase. Deficiencies in tocopherol, vitamin B6 and riboflavin reduce cell numbers in lymphoid tissues of experimental animals and produce functional abnormalities in the cell mediated immune response. Ascorbic acid and tocopherols exert anti-inflammatory effects in studies in man and animals. In humans, dietary supplementation with ascorbic acid, tocopherols and vitamin B6 enhances a number of aspects of lymphocyte function. The effect is most apparent in the elderly.

Animals↗
PubMed2004

Elevation of immune activation in kenyan women is associated with alterations in immune function: implications for vaccine development.

The infectious burden leading to immune activation can vary between different populations and lead to various immune dysfunctions. We compared the effect of immune activation on apoptosis and T cell function in HIV uninfected individuals from Nairobi, Kenya (n=34), and Winnipeg, Canada (n=10). Women from Nairobi had a significantly greater number of CD8+ T cells expressing the activation markers CD38 and HLA DR. Kenyan women also had significantly higher levels of CTLA-4+ CD4 and CD8+ T cells, and reduced levels of CD28+ CD8+ cells. Levels of CD95+ CD4+ T cells were higher in Kenyan women and, correspondingly, showed higher levels of spontaneous apoptosis. Kenyan women also demonstrated hyper-responsiveness to T cell activation as assessed by interferon gamma production. This study demonstrates that in a population of Kenyan women with high levels of T cell activation, there were also elevated levels of T cell apoptotic death and hyper-responsiveness. These differences may influence the efficacy of immune responses to pathogens and must be considered when testing candidate vaccines.

Apoptosis↗
PubMed1980

Restoration of impaired immune functions in aging animals. IV. Action of 2-mercaptoethanol in enhancing age-reduced immune responsiveness.

The enhancing effect of 2-mercaptoethanol (2-ME) on the immune responses of young and old unseparated spleen cells and purified populations of T-cells, B-cells and macrophages was studied. While 2-ME enhances both the normal responses of young cells and the age-reduced responses of old cells, the sulfhydryl compound has a relatively greater enhancing effect on old spleen cells in the humoral response to sheep red blood cells and the blastogenic response to concanavalin A (Con A). The greater enhancing effect in the humoral response appears to be due to 2-ME overcoming a suppressive effect of old T-cells which develops with increasing age. The greater enhancing effect in Con A stimulation appears to be an effect on the Con A responsive sub-population of T-cells and not on the synergistic effect of the presence of B-cells.

Aging↗
PubMed2000

Cellular and molecular aspects of iron and immune function.

Fe plays a critical role in the immune system and defence against infection. However, many aspects of the way in which Fe influences these processes at the molecular and cellular level are unclear. The present review summarizes the role of Fe in lymphocyte activation and proliferation, and discusses how Fe is handled by macrophages.

Humans↗
PubMed1991

Frontal brain asymmetry and immune function.

The relation between brain activity and the immune system was evaluated by assessing immune responses in 20 healthy women who manifested extreme differences in the asymmetry of frontal cortex activation. One group showed extreme and stable left frontal activation; the other group showed extreme and stable right frontal activation. As predicted, women with extreme right frontal activation had significantly lower levels of natural killer cell activity (at effector:target cell ratios of 33:1 and 11:1) than did left frontally activated individuals. This difference did not extend to two other immune measures, lymphocyte proliferation and T-cell subsets. However, higher immunoglobulin levels of the M class were observed in the right frontal group. In this study, the immune patterns could not be accounted for by plasma cortisol levels, anxiety- and depression-related symptomatology, or recent health histories. These findings support the hypothesis that there is a specific association between frontal brain asymmetry and certain immune responses.

Adolescent↗
PubMed2005

Heterologous expression of the filarial nematode alt gene products reveals their potential to inhibit immune function.

BACKGROUND: Parasites exploit sophisticated strategies to evade host immunity that require both adaptation of existing genes and evolution of new gene families. We have addressed this question by testing the immunological function of novel genes from helminth parasites, in which conventional transgenesis is not yet possible. We investigated two such novel genes from Brugia malayi termed abundant larval transcript (alt), expression of which reaches ~5% of total transcript at the time parasites enter the human host. RESULTS: To test the hypothesis that ALT proteins modulate host immunity, we adopted an alternative transfection strategy to express these products in the protozoan parasite Leishmania mexicana. We then followed the course of infection in vitro in macrophages and in vivo in mice. Expression of ALT proteins, but not a truncated mutant, conferred greater infectivity of macrophages in vitro, reaching 3-fold higher parasite densities. alt-transfected parasites also caused accelerated disease in vivo, and fewer mice were able to clear infection of organisms expressing ALT. alt-transfected parasites were more resistant to IFN-gamma-induced killing by macrophages. Expression profiling of macrophages infected with transgenic L. mexicana revealed consistently higher levels of GATA-3 and SOCS-1 transcripts, both associated with the Th2-type response observed in in vivo filarial infection. CONCLUSION: Leishmania transfection is a tractable and informative approach to determining immunological functions of single genes from heterologous organisms. In the case of the filarial ALT proteins, our data suggest that they may participate in the Th2 bias observed in the response to parasite infection by modulating cytokine-induced signalling within immune system cells.

Animals↗
PubMed2001

Vitamin A, infection, and immune function.

In populations where vitamin A availability from food is low, infectious diseases can precipitate vitamin A deficiency by decreasing intake, decreasing absorption, and increasing excretion. Infectious diseases that induce the acute-phase response also impair the assessment of vitamin A status by transiently depressing serum retinol concentrations. Vitamin A deficiency impairs innate immunity by impeding normal regeneration of mucosal barriers damaged by infection, and by diminishing the function of neutrophils, macrophages, and natural killer cells. Vitamin A is also required for adaptive immunity and plays a role in the development of T both-helper (Th) cells and B-cells. In particular, vitamin A deficiency diminishes antibody-mediated responses directed by Th2 cells, although some aspects of Th1-mediated immunity are also diminished. These changes in mucosal epithelial regeneration and immune function presumably account for the increased mortality seen in vitamin A-deficient infants, young children, and pregnant women in many areas of the world today.

Acute-Phase Reaction↗
PubMed1998

Immune function alterations in mice tolerant to delta9-tetrahydrocannabinol: functional and biochemical parameters.

We studied the effect of acute (1 h) or chronic exposure (7 and 14 days) to delta9-tetrahydrocannabinol (delta9-THC) on immune parameters in male Swiss mice. One hour after a dose of 10 mg/kg s.c., the splenocyte proliferative response to ConA and NK activity were not inhibited, but there was a significant decrease in the production of IL-2. After 7 days of treatment, when mice were tolerant to delta9-THC-induced analgesia, these functional parameters were strongly inhibited and there was a persistent reduction in IL-2 and IFNgamma. With 14 days exposure to the drug, splenocyte proliferation was significantly reduced only with 5 microg/ml ConA, and NK activity was still significantly depressed (about 37%). IL-2 had returned to the control value, whereas IFNgamma was still 40% down. Flow cytometry analysis of spleen cell composition indicated no changes after the acute and 7 day treatments, but at 14 days there was a 20% decrease in the number of T lymphocytes, mirrored by a 26% increase of B lymphocytes. In conclusion, in vivo exposure to psychoactive doses of delta9-THC has profound effects on immune function. This implies some important questions in relation to the liberalization of marijuana and its therapeutic uses.

Animals↗
PubMed1994

Dextran 70 administration after trauma-hemorrhagic shock does not impair cellular immune functions.

PURPOSE: Although the effects of the colloid dextran 70 on induction of anaphylactoid reactions or reticuloendothelial phagocytosis have been examined previously, its effects on specific cell-mediated immunity after trauma-hemorrhage shock remain unknown. METHODS: Nonheparinized C3H/HeN mice underwent a laparotomy, were bled, and then maintained at a blood pressure of 35 mm Hg for 60 minutes. Then they were resuscitated with either 4 x the shed blood volume as lactated Ringer's solution (LRS) or 2 x LRS + 1 x dextran 70. Control mice underwent all operative protocols but were neither hemorrhaged, nor resuscitated. At 2 or 24 hours posthemorrhage, serum, splenocytes (SPL), and peritoneal macrophages (pM phi, splenic Mo (sM phi) were obtained. Bioassays were used to determine interleukin-2 (IL-2), IL-3, IL-6, and SPL proliferation. RESULTS: Trauma-hemorrhage markedly depressed lymphokine release, splenocyte proliferation, and IL-6 release at 2 hours after the insult. The combination of LRS + dextran did not restore lymphocyte functions, but also did not further suppress them. The release of IL-6 by pM phi and sM phi at 2 and 24 hours after dextran infusion and serum IL-6 remained at the same level as in LRS-treated animals. CONCLUSIONS: The combination of LRS and colloid dextran 70 does not adversely affect ex vivo cell-mediated immune functions during the first 24 hours after its administration after trauma-hemorrhage. Thus, from the immunological standpoint, dextran is a safe resuscitation adjunct.

Analysis of Variance↗
PubMed1998

Influence of a psychogenic and a neurogenic stressor on several indices of immune functioning in different strains of mice.

It is demonstrated that cell proliferation in response to mitogens, natural killer cell (NK) activity, and macrophage functioning of mice may be influenced by either a neurogenic stressor (footshock) or a psychogenic stressor (exposing the mouse to a predator, namely a rat). The nature and magnitude of the immune changes, however, varied across three strains of mice (BALB/cByJ, C57BL/6ByJ, and CD-1), differing in reactivity to stressors and also as a function of the type of stressor employed. While footshock reduced mitogen-stimulated B-cell proliferation in BALB/cByJ mice, it had the opposite effect in the CD-1 strain. Exposure to the predator, however, had little effect in any of the strains. Macrophage activity and NK cytotoxicity were reduced in response to both stressors in a strain-dependent fashion. Plasma corticosterone in response to footshock was greater in BALB/cByJ than in C57BL/6ByJ mice; however, the strain difference was not evident in response to the psychogenic stressor. It is suggested that analyses of stressor effects on immune functioning need to consider the specific strain/species employed, the particular immune parameters being examined, and the nature of the stressor employed.

Adrenocorticotropic Hormone↗