摘要:

AbstractThe potential of synthetic and natural amphetamines to modulate cellular immune effector and regulatory mechanisms was evaluated in an in vitro exposure system. Murine splenic lymphocytes and elicited peritoneal macrophages were cultured with 0.0001-100μM of amphetamine sulfate, methamphetamine hydrochloride, or the (S) or (R) isomers of cathinone hydrochloride. T-lymphocyte regulatory function was assessed by quantitating the production of cytokines, and T-lymphocyte effector function was assessed by the induction of cytotoxic T-lymphocytes (CTL). B-lymphocyte function was measured by proliferation, and natural immunity was assessed by quantitating basal and IL-2 augmented natural killer (NK) cell activity. None of the compounds tested had any direct effect on cellular viability. Exposure to amphetamine resulted in a significant suppression of IL-2, but not IL-4, production by T-lymphocytes, as well as a suppression of B-lymphocyte proliferation only at the highest amphetamine concentration examined. NK cell function was slightly suppressed by amphetamine exposure, but was enhanced by methamphetamine exposure. Conversely, exposure to either (S) or (R) isomers of cathinone resulted in stimulation of IL-2 production, B-lymphocyte proliferation, and CTL induction. No significant effect of cathinone was noted on NK cell function. These data suggest that natural and synthetic amphetamines exhibit differential immunomodulatory activity following in vitro exposure.

ISSN:0892-3973    

DOI:10.3109/08923979409029897

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractThe ability of lysergic acid diethylamide (LSD) to alter immune function after direct in vitro exposure was examined. It was demonstrated that LSD is able to suppress the proliferation of B-lymphocytes; the production of the cytokines IL-2, IL-4, and IL-6; and the induction of cytotoxic T-lymphocytes at a concentration of 100μM. In vitro exposure to LSD had differential effects on natural killer (NK) cell activity, with significant enhancement of both basal and IL-2-augmented NK cell function at concentrations between 0.0001 and 0.1μM, and suppression of NK response at 100μM. These results demonstrate that LSD may have a direct effect on components of the immune system at concentrations that may be reached upon human exposure.

ISSN:0892-3973    

DOI:10.3109/08923979409029898

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractWe have shown that a traditional Chinese medicine, Xiao-chai-hu-tang (Japanese name: Shosaiko-to) augments natural killer (NK)1activity in mice. The maximum augmentation of NK activity in the peripheral blood and liver was observed at 12 hr after administration of Shosaiko-to. NK activity was augmented by Shosaiko-to dose-dependently. The augmentation became significantly positive at a dose of 500 mg/kg, and the maximum effect was observed at a dose of 1000 mg/kg. The augmentation of NK activity appeared at first in the liver from 6 hr after administration of Shosaiko-to and became detectable later in the peripheral blood from 12 hr after the administration. Activation of NK cells by Shosaiko-to may occur in the liver and subsequently the activated NK cells may be supplied to the peripheral blood. Changes in percentages of cell surface markers (asialo GM1, CD3, CD4, CD8) after Shosaiko-to treatment were hardly detected, but augmentation of NK activity induced by Shosaiko-to was abrogated by anti-asialo GM1 antibody treatment before the cytotoxicity assay. In addition, cytotoxic activity to P-815 target cells was not detected in Shosaiko-to treated mice. Augmentation of NK activity by Shosaiko-to is probably mediated by functional activation of classical NK cells of asialo GM1+phenotype.These results suggest that augmentation of NK activity in the liver is one of mechanisms involved in clinical efficacy of Shosaiko-to in patients with virus chronic hepatitis.

ISSN:0892-3973    

DOI:10.3109/08923979409029899

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractPorphyrins are a group of organic compounds involved in a wide spectrum of fundamental biological processes. Non-metallic, naturally occuring and synthetic porphyrin derivatives may produce cytotoxic effects in malignant or normal tissues exposed to visible light. Supra-clinical doses of the photosensitizing porphyrin, Photofrin®are hematostimulatory when administered to normal and immunosuppressed inbred mice. To determine if a non-photosensitizing metalloporphyrin has similar hematostimulatory activity, we have synthesized iron (III) hematoporphyrin chloride (FeHp) and administered it to sub-lethally irradiated mice. FeHp (10 mgAg) given 1 and 4 days or 1,4 and 7 days following sub-lethal (7 Gy) whole body irradiation significantly increased spleen colony forming units of progenitor cells of the granulocyte-macrophage lineage (CFU-GM) 14 days post-irradiation, relative to irradiated controls. In addition, total splenocyte numbers were significantly increased 17 days post-irradiation in mice that had received FeHp 1 and 4 days post-irradiation. When FeHp was given 24 hours prior to irradiation and again 48 hours or 48 and 96 hours post-irradiation, significant increases in splenic CFU-GM and spleen cell numbers, relative to control mice, were observed 15 days post-irradiation. A non-metallic photosensitising monomeric fraction of Photofrin®, deuteroporphyrin IX, 2,4 (4,2) hydroxyethyl vinyl (HVD) was compared to Photofrin®for its ability to influence the hematopoietic recovery of irradiated mice. Only Photofrin®but not HVD given in 3 doses (10 mg/Ag) 1, 4 and 7 days following irradiation (4.8 Gy) significantly enhanced the recovery of spleen cellularity and splenic CFU-GM. In addition, Photofrin®significantly increased bone marrow CFU-GM 7 and 10 days following the sub-lethal dose ofγ-radiation. The mechanism by which certain porphyrins augment hematopoiesis in the mouse is unknown. However, the identification of FeHp as a non-photosensitising monomeric porphyrin with hematostimulatory activityin vivo, indicates that further study of metalloporphyrins is warranted and may reveal their clinical potential within the context of therapeutically-induced immunosuppression.

ISSN:0892-3973    

DOI:10.3109/08923979409029900

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractThe incorporation of tritiated thymidine into the DNA of murine bone marrow cells could be stimulated by fraction PH-I Ba separated from the roots ofPseudostellaria heterophyllain a dose-dependent mannerin vitro. Moreover, PH-I Ba could induce the differentiation of murine bone marrow cells from pluripotent haemopoietic stem cells into macrophages-like cellsin vitro. Autocrine or paracrine stimulation of granulocyte-macrophage colony stimulating factor was likely to underly the induction of differentiation. Therefore, PH-I Ba was proved to be an immunostimulating agent for mouse marrow hematopoiesis and was found to be a polysaccharide. The sugar components were analyzed by Gas Liquid Chromatography of their alditol acetates.

ISSN:0892-3973    

DOI:10.3109/08923979409029901

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractProtein A (PA), a cell wall glycoprotein of Staphylococcus aureus Cowan I, is known to possess immunomodulatory and antitumor activities. In the present study the effect of protein A on the anti-sheep erythrocyte primary antibody response in normal mice has been investigated. Intraperitoneal administration of PA resulted in suppression of primary antibody response in mice immunized with sheep red blood cells (SRBC) as assessed by plaque forming cell (PFC) assay. The suppressive effect was dose dependent. Maximum suppression in PFC response was observed at 12μgPA/animal and could be observed as low as 1μgPA/animal. The suppression at 6 and 12μgPA/animal was significant when compared with control values (p<0.02 and p<0.001, respectively). However, no significant suppression was recorded at 1μgdose. The suppression was proportional to the numbers of administrations of PA to the mice and critically dependent on the timing of inoculation of PA. PA produced pronounced suppression when injected prior to the immunization of animals with SRBC. PA reduced splenic localization of51Cr labelled SRBC to 55%. It is proposed that the altered localization of antigen (SRBC) in spleen may be responsible for reduced plaque forming cells in normal mice.

ISSN:0892-3973    

DOI:10.3109/08923979409029902

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractThe effects of sodium diethyldithiocarbamate (DTC) on humoral response to SRBC and restoration of the response impaired by a single cyclophosphamide dose (200 mg/kg) were tested on mice. Moreover, the effect of DTC (20 mg/kg) on thymocyte subpopulations was tested on non-immunized mice previously treated with cyclophosphamide.It was found that DTC (20 mg/kg) administered to the immunized mice enhanced humoral response to SRBC, which was reflected in the increased number of PFC and (7S) serum hemagglutinin titer. In contrast, partial restoration of the primary humoral response after DTC injection was observed in the mice administered a single cyclophosphamide dose. The effect of DTC was stronger after 6 days following cyclophosphamide injection, i.e. at the time when spontaneous restoration of T lymphocytes begins. In addition, it was found that DTC given to non-immunized mice treated with cyclophosphamide had a modulating effect on thymocyte subpopulations. Depending on the time of exposure to cyclophosphamide, DTC either increased the percentage of CD4 thymocytes or decreased the percentage of CDS, which subsequently led increased CD4/CD8 coefficient. DTC did not change the suppressing action of cyclophosphamide on the percentage of double-positive thymocytes.

ISSN:0892-3973    

DOI:10.3109/08923979409029903

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractThe immunological status of lead acid batters workers with blood lead levels and urinary delta-aminolevulinic acid (ALA-U) concentrations ranging from safe to toxic levels has been examined and compared with those of non-exposed, age and sex matched controls. No differences in the serum concentrations of IgG, IgA and IgM between the populations were observed and there existed no correlation between blood lead level or ALA-U concentrations and serum immunoglobulin levels. In addition assessment was made of the capacity of peripheral blood mononuclear cells to respond to the mitogen phytohaemagglutin in (PHA), a correlate of T cell function. As before, there was no difference between exposed and control populations and no correlation between reactivity and blood lead concentration. Our data suggest that chronic exposure to lead fail to compromise lymphocyte function in man.

ISSN:0892-3973    

DOI:10.3109/08923979409029904

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor