裂褶菌孢内多糖和孢外多糖对小鼠免疫功能的影响

裂褶菌孢内多糖(SPG₁)和孢外多糖(SPG₂)是分别从发酵培养的裂褶菌菌丝体和发酵液中提取的多糖。SPG₁和SPG₂均能显著促进Con A诱导的小鼠脾淋巴细胞增殖反应,SPG₁还显著地对抗氢可的松对淋巴细胞增殖反应的抑制作用。SPG₁和SPG₂均可恢复14月龄老年小鼠低下的脾淋巴细胞增殖反应。给小鼠ip SPG₁和SPG₂均能显著增强二硝基氯苯(DNCB)所致小鼠迟发型皮肤过敏反应(DCH)。小鼠ip SPG₁可显著增强羊红细胞(SRBC)诱导的小鼠脾脏空斑形成细胞(PFC)反应。SPG₁和SPG₂还可使老年小鼠的PFC反应恢复至成年小鼠水平。     

Enhancement of T lymphocyte proliferation and suppression of antibody producing cell formation by methionine-enkephalin

Methionine-enkephalin (met-enk) 0.1-100 nmol/L significantly enhanced lymphocyte proliferation induced by T cell mitogens. On the other hand, the peptide markedly inhibited splenocyte blastogenesis induced by B cell mitogen lipopolysaccharides (LPS) and sheep red blood cell (SRBC)-driven plaque-forming cell (PFC) formation in vitro. Met-enk alone had no effect on immune responses. However, naloxone 50 nmol/L had also a stimulating effect on Con A-induced splenocyte proliferation. The similar results were also observed in vivo. The results also indicated that the enhancement of T cell function by met-enk was stronger in immunosuppressed mice than in the normal mice.     

Assessment of the immunotoxic potential of the fungicide dinocap in mice.

The immunotoxic potential of dinocap was evaluated in female C57BL/6J mice following in vivo and in vitro exposure to this fungicide. In in vivo studies, groups of mice were dosed by gavage with technical grade dinocap at dosages ranging from 12.5 to 50 mg/kg per day for 7 or 12 days and selected immune functions examined. Mice dosed at 50 mg/kg per day dinocap died after 4 days of dosing. Twelve days of dosing with dinocap at 25 mg/kg per day resulted in decreased thymus weights and cellularity, and increased spleen weights. No changes were observed in body weight, absolute differential peripheral leukocyte counts, the lymphoproliferative responses to B- or T-cell mitogens, the mixed lymphocyte reaction, or natural killer (NK) cell activity of spleen cells from mice exposed to dinocap. Lymphoproliferative responses to concanavalin A (Con A) and phytohemagglutinin (PHA), however, were reduced in thymocytes from mice dosed at 25 mg/kg per day dinocap. The cytotoxic T lymphocyte (CTL) response to P815 mastocytoma cells was enhanced in mice exposed for 7 days to 25 mg/kg per day dinocap. Exposure of mice for 7 days to 25 mg/kg per day dinocap also caused a significant reduction in the IgM and IgG plaque-forming cell (PFC) response to sheep red blood cells (SRBC). A time-course study indicated that dinocap-induced suppression of the IgM PFC response was due to a delay in the peak PFC response to SRBC. In vitro studies using murine thymocytes cultured with dinocap (10 micrograms/ml for 72 h) resulted in suppression of the proliferative response to Con A and PHA. Exposure of thymocytes to dinocap in vitro for as little as 30 min resulted in suppression of the mitogen-stimulated response in the absence of any apparent direct cytotoxic effect. These results suggest that dinocap alters the immune system of the mouse, however, these effects are relatively modest in terms of adverse immune function and are only seen at relatively high exposure levels.     

Cytochrome P450 1B1 is required for 7,12-dimethylbenz(a)-anthracene (DMBA) induced spleen cell immunotoxicity.

7,12-Dimethylbenz(a)anthracene (DMBA) is a potent carcinogen that induces immunosuppression of both humoral and cell-mediated immunity in mice and other species. Previous studies have shown that CYP1B1 is required for bone marrow toxicity produced by DMBA in mice. Therefore, the purpose of these studies was to determine whether CYP1B1 was required for spleen cell immunotoxicity. Female C57BL/6N wild-type (WT) and CYP1B1 knockout (-/-) mice were treated with 0, 17, 50, or 150 mg/kg (cumulative dose) DMBA in corn oil by oral gavage once a day for five days. Several immunotoxicological assays were used to assess the effects of DMBA on systemic immunity. These included the in vitro T-dependent antibody response to sheep red blood cells (SRBC) measured using a direct plaque forming cell (PFC) assay, T- and B-cell mitogenesis induced by Con A and LPS, and nonspecific cell-mediated immunity was evaluated using an NK cytotoxicity assay. In addition, lymphocyte subpopulations were measured by flow cytometry using specific cell surface markers. Following five days of DMBA treatment, the body weights and spleen cell surface markers of the WT and CYP1B1 (-/-) mice showed no significant changes. A decrease in NK activity was found at the 50 mg/kg DMBA dose in WT mice, but not in the CYP1B1 (-/-) mice. Interestingly, at the 150 mg/kg dose of DMBA, CYP1B1 null mice had decreased NK activity, whereas WT mice did not. The SRBC PFC response demonstrated that the IgM antibody response was suppressed by DMBA in WT mice in a dose-dependent manner (significant at 50 and 150 mg/kg). However, there were no changes in the SRBC PFC responses in any DMBA test group in the CYP1B1 (-/-) mice. Similarly, while DMBA suppressed B- and T-cell mitogenesis at the 50 and 150 mg/kg dose levels in C57BL/6N WT mice, no effect was seen in CYP1B1 (-/-) mice. Thus, CYP1B1 appears to be critical for the immunosuppression of DMBA in mice, suggesting a role for bioreactive metabolites in the spleen cell immunotoxicity produced by DMBA.     

异丙肌苷对小鼠免疫功能的增强作用

在正常小鼠和注射环磷酰胺所致的免疫功能抑制的小鼠,异丙肌苷)25,50,100mg/kg,ip)能显著促进溶血素生成;增加空斑形成细胞数;增强二硝基氯苯所致迟发型皮肤超敏反应。在16月龄老年小鼠,异丙肌苷(2.5mg/kg,ip)可使减少的空斑形成细胞数增加至接近3月龄小鼠的水平,加大剂量作用反减弱或使空斑形成细胞数显著减少。体外试验,异丙肌苷(5,10,20mg/L)可显著增强刀豆素A诱导的C57 BL/6J小鼠的淋巴细胞增殖反应,并使16月龄老年小鼠低下的刀豆素A诱导的淋巴细胞增殖反应明显恢复。     

Modification of immune response by cinnarizine

Effects of cinnarizine on immune response in mice were investigated. Mice were orally administered with cinnarizine and were immunized with sheep red blood cells (SRBC) intravenously. Numbers of plaque forming cells (PFC) to SRBC in spleen of these mice were assayed and delayed-type hypersensitivity (DTH) response to SRBC was measured. 1) PFC response in immunization with 5 X 10(6) cells/mouse of SRBC was enhanced by administration of 25 mg/kg of cinnarizine, while the response in immunization with 5 X 10(8) cells/mouse was suppressed by 25 to 200 mg/kg of cinnarizine. 2) From study on timing of administration, suppression of PFC response by 6.25 to 200 mg/kg of cinnarizine was observed at 24 hr. after the immunization. 3) 12.5 to 200 mg/kg of cinnarizine suppressed polyclonal B cell activation induced by lipopolysaccharide (LPS). 4) Colchicine induced suppressor T cell inactivation was prevented by administration of 50 mg/kg of cinnarizine and it was suggested that cinnarizine may induce suppressor T cells from the study of adoptive cell transfer system. 5) 50 mg/kg of cinnarizine showed the suppression of DTH response in expression phase, but not in induction phase. It was concluded that immune responses in mice were modified by cinnarizine.     

蜜环菌多糖对小鼠免疫功能的影响

蜜环菌多糖(100mg/kg·d×5d,ig)能显著增加正常小鼠和注射环磷酰胺所致免疫功能抑制小鼠的溶血素生成。当剂量为50mg/kg·d×5d,ig时,它还能显著增加正常小鼠的空斑形成细胞数。体外试验,蜜环菌多糖(10、50μg/ml)显著增强刀豆素A诱导的小鼠淋巴细胞增殖反应,但对二硝基氯苯所致小鼠迟发型过敏反应无显著增强作用。此外,蜜环菌多糖还能增加小鼠静注碳粒廓清速率及腹腔巨噬细胞的吞噬百分数和吞噬指数。     

雷公藤甲素对炎症及免疫功能的影响

雷公藤甲素能减轻巴豆油合剂诱发的小鼠耳部水肿;对醋酸所致小鼠扭体反应有明显的抑制作用;对细胞膜有稳定作用。甲素可明显提高大鼠血清总补体含量;抑制初次免疫反应的溶血素的形成;对腹腔巨噬细胞的吞噬活性似有一定程度的抑制。甲素对再次免疫反应的抗SRBC的抗体形成无明显抑制,大剂量甲素可使大鼠睾丸精子形成受到抑制,心、肝、肾组织出现变性,脾小体变小,淋巴细胞减少,口服及皮下注射的LD50分别为1195μg/kg及1136μg/kg。     

Evaluation of the Immunotoxicity of Orally Administered 2-Methoxyacetic Acid in Fischer 344 Rats

Evaluation of the Immunotoxicity of Orally Administered 2-MethoxyaceticAcid in Fischer 344 Rats. SMIALOWICZ, R. J., RIDDLE, M. M.,ROGERS, R. R., COPELAND, C. B., LUEBKE, R. W., AND ANDREWS,D. L. (1991). Fundam. Appl. Toxicol. 17, 771–781. We previouslydemonstrated that the glycol ether 2-methoxyethanol (ME) isimmunotoxic in the rat. In this study, the immunotoxicity of2-methoxyacetic acid (MAA), the principal metabolite of ME,was evaluated in adult male Fischer 344 rats. Rats were dosedby gavage with MAA on 10 consecutive days at dosages rangingfrom 50 to 200 mg/kg/day. Thymic involution, in the absenceof body weight loss, was observed at 100 and 200 mg/kg/day MAA.Lymphoproliferative responses to the mitogens concanavalin A,phytohemagglutinin, and pokeweed mitogen were also reduced atthese dosages. The in vitro generated cytotoxic T lymphocyteresponse was reduced at 200 mg/kg/day MAA. The mixed lymphocytereaction and natural killer cell activity were unaffected byexposure to MAA. Enumeration of splenic lymphocyte populationsrevealed a reduction in the percentage of W3/25-positive cellsat 100 and 150 mg/kg/day and an increase in the percentage of0X39-positive cells at 200 mg/kg/day; however, no changes inthe absolute number of either of these subsets were observed.The plaque forming cell (PFC) response to trinitropheny-lipopolysaccharide(TNP-LPS) was suppressed at 50-200 mg/kg/day MAA, while thePFC response to sheep red blood cells (SRBQ was elevated at50 mg/kg/day. Immunization of rats with TNP-LPS or SRBC followedby oral exposure to MAA at 4 and 28 hr postimmunization resultedin the suppression of the PFC response to TNP-LPS and SRBC atdosages of 100 and 200 mg/kg and 200 and 400 mg/kg, respectively.Equal suppression of the PFC response to TNP-LPS was achievedat equimolar concentrations of ME and MAA. The effects of MAAon the immune system of the rat presented here are very similarto results reported from this lab for ME-induced immune alterations.These results, along with results of experiments in which ME-inducedsuppression of the PFC response to TNP-LPS was reversed by 4-methylpyrazole,an inhibitor of the oxidation of ME to MAA by alcohol dehydrogenase,indicate that MAA is the proximate immunotoxicant followingexposure to the glycol ether 2-methoxyethanol.     

消旋β-苯基乳酸钠对小鼠免疫功能的影响

消旋β-苯基乳酸钠(PLA-Na)是丹参素(DSS)的衍生物之一。本文报道PLA-Na及DSS在试管内显著抑制小鼠脾细胞增殖,抑制溶血空斑形成。整体给药能明显抑制初次与再次致敏的脾细胞中溶血空斑细胞的形成;对二硝基氯苯所致小鼠皮肤迟发性超敏反应有一定抑制作用。     

In vivo and in vitro effects of 1,1-dimethylhydrazine on selected immune functions

The in vivo phase of the experiments reported here include the evaluation of immune function after short-or long-term treatment of mice with 1,1-dimethylhydrazine (UDMH). Long-term exposure (3 injections/week for 14 weeks) resulted in increased numbers of Jerne plaque-forming cells, a trend toward decreased induction of suppressor cell activity by concanavalin A (Con A), and no effects on mitogen-induced lymphocyte blast transformation (LBT), compared to saline-treated control mice. These effects were greatest at doses of 10 or 50 mg/kg, while higher doses had less of an effect. In vitro experiments were performed by adding UDMH to normal murine splenocytes in the LBT assay and con A-induced suppressor cell assay. The UDMH induced a significant enhanced response to lipopolysaccharide (LPS) at 10 and 50 micrograms/ml, and a suppressed response to both Con A and LPS at higher concentrations. The UDMH also caused a decrease in suppressor cell activity at 25 micrograms/ml. Selective abrogation of suppressor activity or alteration of the suppressor cell-helper ratio were suggested as possible mechanisms for the enhancement effect associated with UDMH.     

北沙参多糖的免疫抑制活性

北沙参为伞形科珊瑚属植物珊瑚菜(Glehnia littoralis F.Schmidt ex Mig.)的根,是一种常用中药,具有养阴清肺功能。据报道北沙参可延长家兔抗甲胎球蛋白抗体的存在时间。不少植物多糖,如人参、黄芪、刺五加和当归等的多糖成分,对机体的免疫功能有促进作用。为此我们观察了北沙参的多糖成分对机体免疫功能的影响。     

Immunosuppression following exposure to 7,12-dimethylbenz[a]anthracene (DMBA) in Ah-responsive and Ah-nonresponsive mice

Recent reports suggest that the immunotoxicity of certain polycyclic aromatic hydrocarbons is associated with the Ah locus in mice. To test whether immunosuppression mediated by 7,12-dimethylbenz[a]anthracene (DMBA) is regulated by the Ah locus, several endpoints of immune function were measured in Ah-responsive B6C3F1 and Ah-nonresponsive DBA/2N and in Ah-congenic C57BL/6J (responsive B6-AhbAhd and nonresponsive B6-AhdAhd) mice dosed sc with up to 100 micrograms/g DMBA in corn oil. Some groups of B6C3F1 and DBA/2N mice were exposed to 100 micrograms/g benzo[a]pyrene (B(a)P) or 1 nmol 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) for determination of hepatic microsomal monooxygenase activity. The body weights of all mice were unaffected by DMBA exposure, but thymus weights and spleen cellularity were decreased. Antibody plaque-forming cells (PFC) measured 4 days after iv sheep erythrocyte (SRBC) immunization were suppressed 99% in B6C3F1 and 96% in DBA/2 mice. Antibody PFC after in vitro immunization to SRBC were similarly suppressed 98% in both B6-AhbAhd and B6-AhdAhd Ah-congenic mice exposed to 100 micrograms/g DMBA. Responses to the T-cell mitogens concanavalin A and phytohemagglutinin were significantly suppressed in both B6C3F1 and DBA/2N strains, as was mitogenesis to bacterial lipopolysaccharide. The unidirectional mixed lymphocyte responses of the congenic strains were suppressed 76% in B6-AhbAhd and 85% in B6-AhdAhd, cytotoxic lymphocyte generation was suppressed 68% in B6-AhbAhd and 78% in B6-AhdAhd. The overall differences between immunosuppressive responses in splenocytes from B6-AhbAhd and B6-AhdAhd congenics were not significant. Induction of cytochrome P1-450, a marker of Ah responsiveness, was determined by 7-ethoxycoumarin O-deethylase monooxygenase activity in hepatic microsomes or splenocytes. This monooxygenase activity was not significantly increased in either B6C3F1 or DBA/2 mice exposed to DMBA, whereas B(a)P and TCDD exposure significantly induced enzyme activity in B6C3F1 hepatocytes. These data suggest that DMBA has an immunosuppressive action on murine splenocytes which is independent of the Ah locus and associated induction of cytochrome P1-450 xenobiotic-metabolizing enzymes.     

Appropriate conditions for the plaque forming cell (PFC) assay in rats and effects of cyclophosphamide on PFC response.

The appropriate conditions for the plaque forming cell (PFC) assay using rat splenocytes were determined and effects of cyclophosphamide on PFC response were investigated using these conditions. The number of PFCs produced by immunization with a suspension of sheep red blood cells (SRBCs) was higher with i.v. injection than with i.p. injection. Subcutaneous injection of the suspension did not produce PFCs. The highest PFC response was observed when the number of PFCs was determined 4 days after i.v. immunization with 0.5 ml of a 1% SRBC suspension. Cyclophosphamide (3, 10, 30, 100 and 300 mg/kg, p.o.) dose-dependently decreased PFC response under the above-mentioned optimal conditions, and decreased PFC responses were noted even at the very low dose of 3 mg/kg: a dose at which a decrease in the number of PFCs has not been reported in studies using mice. From these results, the appropriate conditions for the PFC assay in rats are considered to be i.v. immunization with 0.5 ml of a 1% SRBC suspension and determination of the number of PFCs 4 days after immunization. Furthermore, it is considered that the PFC assay using rats might be more sensitive to immunosuppressive agents than that using mice.     

Altered immune response during cadmium administration in mice

C57BL/6 mice were administered 50 or 200 ppm of Cd as CdCl2 in the drinking water for either 3 to 4 (short term) or 9 to 11 (long term) weeks. In other experimental designs, mice were exposed orally to 300 ppm of Cd or injected with 2.5 mg/kg of Cd ip. The proliferative response to the T cell mitogens Con A and PHA was increased in cultures of spleen cells from orally treated mice in most of the experiments performed. After primary immunization with sheep red blood cells, the number of IgM antibody forming cells per 10(7) spleen cells was also moderately higher in mice exposed to 50 or 200 ppm of Cd for short or long term. In contrast, long-term exposure to 300 ppm of Cd depressed the antibody response to SRBC. Administration of ZnCl2 prevented the enhancement of the PFC response in mice orally administered 50 ppm of Cd. The capacity to suppress the antibody response of spleen cells preincubated with sodium periodate was decreased after short-term oral or ip. Cd administration but was completely or partially recovered after long-term exposure to either 50 or 200 ppm of Cd.     

国产环孢素A对小鼠免疫功能的抑制作用

当剂量为25～100mg/kg·d~(-1),ig×4d时,国产环孢素A(CsA)显著抑制小鼠脾脏空斑形成细胞数和溶血素生成,并呈剂量依赖方式。该剂量给药10d,可显著抑制2,4—二硝基氯苯所致小鼠迟发型皮肤超敏反应。CsA(50 mg/kg·d~(-1),ig×14d)能明显延长小鼠移植心脏的存活时间。CsA(50,100mg/kg·d~(-1),ig×4d)对小鼠iv碳粒廓清速率和骨髓细胞数均无明显影响。国产CsA和进口CsA对小鼠脾脏空斑形成细胞反应的抑制作用无显著差异。     

Chemical Dissection of the Primary and Secondary in Vitro Antibody Responses with Butylated Hydroxyanisole and Gallic Acid

ABSTRACT

The effects of butylated hydroxyanisole (BHA), an antioxidant food additive and gallic acid (GA), a food additive metabolite, were further studied in the Mishell-Dutton in vitro system. BHA added to cultures at 50-75 ug/ml suppressed the primary IgM plaque-forming cell (PFC) response to the thymus-dependent antigen sheep erythrocytes (SRBC). The suppression was not due to overt cytotoxicity and could not be reversed by adding 2-mercaptoethanol (2ME), a macrophage (MØ) substitute, to the system. Spleen cell cultures from mice primed in vivo with SRBC (secondary IgM response) were also suppressed by 50-75 ug/ml BHA; however, the PFC response was in part restored by adding 2ME to cultures at the start of the culture period. The data suggest that BHA, at certain critical doses, is preferentially suppres-sive to non-primed (virgin) B- and T-lymphocytes and Mø. Substituting 2ME for adversely affected Mø can restore the response of the more BHA-resistant antigen-primed B- and T-lymphocytes. GA suppressed both the primary and secondary PFC responses, but in contrast to BHA, 2ME fully restored the response in both instances; this suggests that GA has no effect on primed and non-primed B- or T-lymphocytes, but is suppressive because of its specific effects on Mø-dependent lymphocyte functions.     

The Broiler Chicken as a Model for Immunotoxicity Assessment: 1. Standardization of in Vitro Immunological Assays

The Broiler Chicken as a Model for Immunotoxicity Assessment.1. Standardization of in Vitro Immunological Assays. BAECHER-STEPPAN,L., NAKAUE, H. S., MATSUMOTO, M., GAINER, J. H., AND KERKVLIET,N. I. (1989). Fundam. Appl. Toxicol. 12, 773–786. Thebroiler chicken was developed as an alternative animal modelto laboratory rodents for immunotoxico-logic assessment. Invivo treatment with 100–200 mg/kg cyclophosphamide (CY)was used as a known immunosuppressive treatment to standardizethe assay systems. Protocols for assessing specific immunologicalfunctions were developed in specific pathogen-free (SPF) broilersto measure lymphocyte blastogenesis to T-cell (concanavalinA and phytohemagglutinin) and B cell (Staphylococcus aureuscells) mitogens, delayed-type hypersensitivity (Dm) to tuberculin,natural killer (NK) cell cytotoxicity, plaque-forming cell (PFC)response to sheep red blood cells (SRBC), and serum antibodytiters to SRBC. CY was an effective immunosuppressant in thebroiler system for assessment of lymphocyte responsiveness tomitogenic stimulation, DTH reactivity, and the antibody responceto SRBC as assessed by PFC and serum antibody titers. NK cytotoxicitywas not altered on a cellular level following treatment withCY at a dose that preduced greater than 75% depletion of spleencellularity. However, under these conditions, it must bc assumedthat the capacity of CY-treated birds to mediate NK effectorfunctions would be reduced. These results demonstrate the applicabilityof the broiler chicken as an animal model for immunotoxicitytesting.     

灵芝多糖对混合淋巴细胞培养反应中白细胞介素2生成和T细胞亚类的影响(英文)

利用混合淋巴细胞培养反应研究了灵芝多糖的免疫作用机理。结果表明培养12h,灵芝多糖(25,50,100,200μg/ml)可促进白细胞介素2的分泌,且具有剂量依赖关系。培养4d后,可增加总的细胞回收量以及Lyt 2⁺和L3T4⁺细胞的回收量。灵芝多糖还明显增强细胞毒T细胞的功能,在浓度为200μg/ml时,其杀伤活性增加100%。