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Anne H van der Spek, Eric Fliers, and Anita Boelen

the immune response ( Boutzios & Kaltsas 2000 , Klein 2006 , De Vito et al . 2011 ), and there is an extensive body of literature available on the effects of TH on various types of innate immune cells ( De Vito et al . 2011 ). However, very few of

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Milos Mraz and Martin Haluzik

-grade inflammation characterized by increased infiltration of immune cells into AT and increased production and subsequent secretion of proinflammatory factors into circulation ( Neels & Olefsky 2006 ). This review has focused on the various subsets of immune cells

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Siobhan M Donnelly, Bao Tran Nguyen, Scott Rhyne, Jordan Estes, Subrina Jesmin, and Chishimba Nathan Mowa

epithelial cells and the whole uterine cervical tissue in general, notably the effect of VEGF on the recruitment of immune cells to the uterine cervical epithelia and lumen. Materials and methods Animals Pregnant and nonpregnant (ovariectomized) C57BL6

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S Yellayi, MA Zakroczymski, V Selvaraj, VE Valli, Ghanta V, WG Helferich, and PS Cooke

The soy phytoestrogen, genistein, induces thymic atrophy when administered to ovariectomized mice by injection or in the diet. Injected genistein also causes decreased humoral immunity, but the effects of genistein on cell-mediated immunity have not been addressed. Here we examined effects of injected and dietary genistein on cell-mediated immune responses. Female C57BL/6 mice (25- to 27-days-old) were ovariectomized, then placed on phytoestrogen-free feed 5 days later. Seven days after ovariectomy, they were given daily subcutaneous injections of either dimethylsulfoxide (DMSO) or genistein (8, 20, 80 mg/kg) for 28 days; some mice were given 80 mg/kg genistein plus the anti-estrogen ICI 182,780 (5 mg/kg/week). Cell-mediated immune response was tested by analyzing the delayed-type hypersensitivity (DTH) response to a hapten, 4-hydroxy-3-nitrophenyl acetyl succinimide (NP-O-SU), at the end of treatment. Reversibility of the effects of genistein was tested by measuring the DTH response in mice that were given genistein (20 or 80 mg/kg) for 28 days, then allowed to recover for 28 days. To determine if dietary genistein could affect cell-mediated immunity, mice ovariectomized as above were fed genistein at 0, 1000 or 1500 parts per million (ppm) for 28 days. There was a 46-67% decrease in the DTH response in the footpads of mice injected with 8-80 mg/kg genistein compared with controls (P<0.05 vs control for all treatment groups); these effects were reversible. On histopathological examination of the feet, there was decreased cell infiltration in genistein-treated animals compared with controls, and the numbers of CD4(+) and CD8(+) T cells in popliteal lymph nodes were reduced. The effects of genistein are mediated through both estrogen receptor (ER) and non-ER pathways, as the anti-estrogen ICI 182,780 only partially blocked the effects of genistein on the DTH response. Dietary genistein (1000 or 1500 ppm) decreased cell-mediated immunity while producing serum genistein concentrations in the physiological range for humans under certain nutritional conditions. Further work is needed to determine if dietary genistein and phytoestrogen exposure can produce effects on cell-mediated immunity in humans or other animals under various nutritional conditions.

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AM ten Bokum, EG Lichtenauer-Kaligis, MJ Melief, PM van Koetsveld, C Bruns, PM van Hagen, LJ Hofland, SW Lamberts, and MP Hazenberg

Somatostatin is a neuropeptide that is widely distributed throughout the body. It acts as a neurohormone and a neurotransmitter and may also have an immunomodulatory role. The genes for five subtypes of somatostatin receptors (sst) have been cloned, suggesting that the diverse effects of the peptide might be mediated by different receptors. We are interested in studying the role of sst ininflammation, using an animal model. Because of the up-regulation of sst expression in inflamed joints in human rheumatoid arthritis, we chose rat adjuvant arthritis as an experimental model. In order to determine which of the sst subtypes might be important in immune modulation, subtype expression in leukocytes isolated from different lymphoid tissues of the rat was studied. Also, the expression levels of the most abundantly expressed sst mRNAs in leukocytes from spleen and blood were compared in rats with adjuvantarthritis and controls, using a semi-quantitative approach. Furthermore, the effect of systemic administration of a long-acting somatostatin analogue, octreotide, which binds selectively to sst subtypes 2 and 5 (sst2 and sst5), on the incidence and the severity of rat adjuvant arthritis, was studied. The main sst expressed in cells of the rat immune system, both resting and activated, were found to be sst3 and sst4. This contrasts with the human and murine situations, in which sst2 appears to be the main subtype expressed in the immune system. No quantitative differences in sst subtype mRNA levels in leukocytes from spleen and blood were found between rats with adjuvant arthritis and controls. Finally, no effect of systemic administration of octreotide on either the incidence or severity of adjuvant arthritis in Lewis rats was found. As octreotide binds selectively to sst2 and sst5, the absence of an immunomodulatory effect of this analogue in rat adjuvant arthritis corroborates our finding that these sst subtypes are not expressed in cells of the rat immune system. In conclusion, cells of the rat immune system appear to express a spectrum of sst (sst3 and sst4) different from that found in human granulomatous and autoimmune disease (mainly sst2). Therefore, the rat adjuvant arthritis model appears to be suitable only for studying the immunomodulatory effects of somatostatin analogues which have a high affinity for sst3 and sst4, but not for studying the immunomodulatory effects of octreotide, which has a high affinity only for sst2 and sst5.

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D. J. J. Carr, B. R. DeCosta, C.-H. Kim, A. E. Jacobson, V. Guarcello, K. C. Rice, and J. E. Blalock

ABSTRACT

Opioid peptides have been shown to modulate various parameters of both the humoral and cellular arms of the immune system. The modulatory capacity of the peptides can often be substantially reduced in the presence of naloxone, an opioid receptor antagonist, indicating a classical ligand-receptor interaction. In order to characterize these interactions further, we investigated the characteristics of opioid receptors on a macrophage cell line, P388d1. A δ-class opioid receptor was found with an M r of 58 000. We also identified opioid receptors on MOLT-4 (T-cell) and IM-9 (B cell) cell lines as well as thymocytes and T celland B cell-enriched populations. Using the central (brain) κ-selective agonist, U-69,593, it was also determined that P388d1 cells possess κ-like opioid receptors. Scatchard analysis of the binding of [3H]U-69,593 revealed a single population of sites with a dissociation constant of 17 ± 3 (s.e.m.) nmol/l and a total number of binding sites of 53·8 ± 1·0 (s.e.m.) fmol/106 cells. Moreover, the racemic κ-selective agonist U-50,488H was able to displace 50% of [3H]U-69,593 binding at 8·0 nmol/l, whereas other opioid ligands such as [Met]-enkephalinamide (δ-selective) and [d-Ala2,N - Me - Phe4,Gly5 - ol] - enkephalin (μ - selective) were ineffective displacers of [3H]U-69,593 except at high concentrations.

Journal of Endocrinology (1989) 122, 161–168

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J. R. WALL, P. TWOHIG, and B. CHARTIER

A possible effect of thyroid hormones on numbers of mononuclear cells and immune reactivity has been studied in hyperthyroid and hypothyroid guinea-pigs and rats. There were no major changes in populations of blood mononuclear cells in hyperthyroid or hypothyroid animals compared with populations in euthyroid animals. Although there was some evidence for depressed cell-mediated responses to an extract of Candida (monilia) albicans in hyperthyroid rats as assessed by skin tests, this was minor, and responses in tuberculin purified protein derivative (PPD) were normal in all groups, whilst production of macrophage migration inhibition factor in response to PPD and Candida was similar in the three groups of animals. Antibody responses to sheep red blood cells, a thymic-dependent antigen, tended to be depressed in hyperthyroid and hypothyroid rats and increased in hyperthyroid and hypothyroid guinea-pigs, although this was significant only for hyperthyroid guinea-pigs 16 days after immunization. Responses to trinitrophenol-Ficoll, a thymic-independent antigen, were similar to the three groups of guinea-pigs. Thus, a major effect of excess or deficiency of thyroid hormone on immune responses to foreign antigens has not been demonstrated, although it is possible that immune reactions against thyroid antigens may be more sensitive to the effect of thyroid hormones than responses to foreign antigens.

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CV Clevenger, DO Freier, and JB Kline

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A. D. Perris, D. J. Edwards, and M. J. Atkinson

ABSTRACT

Xenografts of mouse tail skin to the rib cages of normal and sham-parathyroidectomized rats caused an increase in plasma calcium concentration and concomitant increase in bone marrow mitosis. Neither was elicited in aparathyroid rats and graft survival was prolonged in these animals.

No hypercalcaemic episode was associated with the delayed hypersensitivity response induced by painting rat ears with oxazolone. Compared with the response in sham-parathyroidectomized rats, that in parathyroidectomized rats was enhanced although both responses were less than that in normal rats.

Parathyroidectomy of parental donors did not affect the ability of their splenic lymphocytes to mount a graft-versus-host response in F1 hybrid recipients. When sham-operated and aparathyroid parents were sensitized with F1 hybrid lymphocytes no differences were observed in a subsequent graft-versus-host response in F1 recipients. However, when aparathyroid F1 recipients were employed a marked reduction in the graft-versus-host reaction was observed.

Thus the clonal expansion of cells with specific reactivity to certain antigens in secondary lymphoid tissue, which is driven by those same specific antigens, is not affected or only moderately affected by the parathyroid status of the animal. However, the more general increase in lymphocyte numbers promoted by non-specific mitogenic lymphokines is markedly impaired in the hypocalcaemic parathyroidectomized rat. Furthermore, the parathyroid gland is essential for the development of a hypercalcaemic episode which follows antigenic challenge and causes cell proliferation in primary lymphoid tissues. This surge of mitosis could serve to replenish the depleted pools of virgin T and B lymphocytes in the secondary lymphoid tissue which occur as a result of their response to antigens.

J. Endocr. (1984) 102, 257–263

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V Geenen, JF Poulin, ML Dion, H Martens, E Castermans, Hansenne I, M Moutschen, RP Sekaly, and R Cheynier

Although the thymus constitutes a target organ for most protein and steroid hormones, it has been quite difficult to determine the precise control exerted in vivo by the endocrine system upon thymic function. The biological role of the thymus is to ensure the generation of a diversified population of peripheral T cells able to respond to non-self-antigens but nevertheless tolerant to self-antigens. For a long time, thymic function could not be monitored, as a consequence of the absence of adequate technology to differentiate recent thymic emigrants from naive T cells. The generation of T cell receptor (TCR) diversity occurs in the thymus through recombination of gene segments encoding the variable parts of the TCR alpha and beta chains. During these processes, by-products of the rearrangements are generated in the form of TCR excision circles (TRECs). As these molecules are lost upon further cell division, their quantification is actually considered as a very valuable tool to estimate thymic function. The most appropriate TREC is deltaRec-Psi(J)alpha TREC or signal joint TREC resulting from deltaRec-Psi(J)alpha rearrangement (TCRD deletion) that occurs late during thymopoiesis, before V(alpha)-J(alpha) rearrangement. Here we describe how TREC quantification is a powerful and reliable method to evaluate the impact of hormones and endocrine disorders upon thymic function.