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1.
HLA-B27 transgenic (TG) rats develop spontaneous colitis when colonized with intestinal bacteria, whereas athymic nude (rnu/rnu) HLA-B27 TG rats remain disease free. The present study was designed to determine whether or not HLA-B27 expression on T cells is required for development of colitis after transfer of mesenteric lymph node (MLN) cells into rnu/rnu HLA-B27 recipients. Athymic nontransgenic (non-TG) and HLA-B27 TG recipients received MLN cells from either TG or non-TG rnu/+ heterozygous donor rats that contain T cells. HLA-B27 TG rnu/rnu recipients receiving either non-TG or TG MLN cells developed severe colitis and had higher caecal MPO and IL-1beta levels, and their MLN cells produced more IFN-gamma and less IL-10 after in vitro stimulation with caecal bacterial lysate compared to rnu/rnu non-TG recipients that remained disease free after receiving either TG or non-TG cells. Interestingly, proliferating donor TG T cells were detectable one week after adoptive transfer into rnu/rnu TG recipients but not after transfer into non-TG recipients. T cells from either non-TG or TG donors induce colitis in rnu/rnu TG but not in non-TG rats, suggesting that activation of effector T cells by other cell types that express HLA-B27 is pivotal for the pathogenesis of colitis in this model.  相似文献   

2.
土茯苓对细胞免疫和体液免疫的影响   总被引:34,自引:0,他引:34  
土茯苓水提取物在抗原致敏后及攻击后给药均明显地抑制了picryl chloride(PC)所致的小鼠接触性皮炎(PC-DTH)和绵羊红细胞(SRBC)所致的足蹠反应(SRBC-DTH),其中攻击后给药时作用较强.土茯苓还明显地抑制了二甲苯所致的耳壳及蛋清所致的小鼠足蹠炎症反应。此外,土茯苓对小鼠抗SR-BC 抗体形成的细胞数(IgM-及IgG-PFC 数)无明显影响,但其溶血空斑明显地较对照组为大,同时,血清溶血素水平未见降低,而呈增加趋势。以上结果表明,土茯苓对体液免疫反应无抑制作用,但可选择性地抑制细胞免疫反应,后者主要系影响致敏T 淋巴细胞释放淋巴因子以后的炎症过程。  相似文献   

3.
Approximately 20% of normal blood lymphocytes expressing the T-helper (Leu 3/T 4+) surface phenotype display natural killer (NK)-like features such as cytoplasmic granules and the ability to bind NK-cell targets. In this study, we have assessed the frequency, phenotypic features, and functional capabilities of such cells in a variety of lymphoid malignancies or solid tumors. In each patient group, the percentage of granular lymphocytes within the Leu 3/T 4+ T-helper subset was significantly increased. A large percentage of these cells coexpressed the Leu 7 or Leu 15 marker. When Leu 3+ cells from patients with high proportions of such NK-like cells (or Leu 3+-Leu 15+ cells from selected patients) were isolated with a fluorescence-activated cell sorter, these cells did not proliferate in response to allogeneic cells or T-cell mitogens, nor did they provide help for B-cell differentiation. They also did not suppress T-cell proliferative responses or B-cell differentiation. Freshly prepared Leu 3+ granular lymphocytes did not display NK-cell cytotoxic functions. However, after short-term culture in the presence of phytohemagglutinin (PHA), Leu 3+-Leu 15+ cells expressed T-cell growth factor (TCGF) receptors, had a detectable proliferative response to exogenous TCGF, and acquired the ability to lyse NK-cell targets. These studies demonstrate that, in a variety of malignancies, the lymphocyte subpopulation expressing the T-helper (Leu 3/T 4+) phenotype may be comprised largely of cells with NK-like features and functional capabilities distinct from those of classical helper T cells.  相似文献   

4.
The interaction between receptor activator of nuclear factor-kappaB ligand (RANKL) and RANK has been reported to regulate immunity in addition to bone metabolism. The aim of this study was to determine if osteoprotegerin (OPG), an inhibitor of the RANKL-RANK interaction and possibly a new drug against osteoporosis, would adversely affect immunity. OPG was used to treat mice developing different models of cellular and humoral immune responses and also in vitro in T and B cell assays. In mice, OPG does not affect cell-mediated reactions such as contact hypersensitivity to the hapten oxazolone and liver damage, granuloma formation, and infectious load induced by mycobacterial infection. However, OPG increases humoral reactions such as the production of IgM, IgG, and IgE against the T cell dependent antigen keyhole limpet hemocyanin and the production of IgM against the T cell independent antigen Pneumovax. In vitro, OPG modestly co-stimulates T cells but does not affect the proliferation of B cells. OPG has modest immunoregulatory effects that seem to be confined to the humoral response to specific antigens.  相似文献   

5.
小鼠肥大细胞瘤P815模型的建立与初步应用   总被引:4,自引:2,他引:2  
目的 建立小鼠肥大细胞瘤P815种植瘤模型,并对其体内诱发特异性CTL应答机理进行初步的研究。方法 经有限稀释法筛选P815单克隆瘤系,用RT-PCR及产物DNA测序鉴定肿瘤抗原P1A基因的表达;在此基础上,用活瘤苗免疫同系小鼠,经标准^51Cr释放试验检测在体特异性CTL的活性。结果 筛选出了一个P815单克隆成瘤系P81-F3,并鉴定该瘤存在P1A基因的表达,用活瘤疫苗免疫6只步鼠,在3只体内  相似文献   

6.
《Immunity》2023,56(8):1910-1926.e7
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7.
Distributed throughout the body, lymph nodes (LNs) constitute an important crossroad where resident and migratory immune cells interact to initiate antigen-specific immune responses supported by a dynamic 3-dimensional network of stromal cells, that is, endothelial cells and fibroblastic reticular cells (FRCs). LNs are organized into four major subanatomically separated compartments: the subcapsular sinus (SSC), the paracortex, the cortex, and the medulla. Each compartment is underpinned by particular FRC subsets that physically support LN architecture and delineate functional immune niches by appropriately providing environmental cues, nutrients, and survival factors to the immune cell subsets they interact with. In this review, we discuss how FRCs drive the structural and functional organization of each compartment to give rise to prosperous interactions and coordinate immune cell activities. We also discuss how reciprocal communication makes FRCs and immune cells perfect compatible partners for the generation of potent cellular and humoral immune responses.  相似文献   

8.
Cryopreserved human peripheral blood mononuclear cells (PBMC) were tested for natural killer (NK) and antibody-dependent cellular cytotoxicity (ADCC) and for high-affinity (29°C) and total (4°C) rosette formation with sheep erythrocytes. PBMC produced variable NK activity following freezing and thawing, but consistently reacted well in ADCC. A significant correlation was found between low NK activity and a decreased percentage of low-affinity rosette-forming cells. On the contrary, the number of large granular lymphocytes (LGL), among which NK cells are restricted, and the reactivity with the monoclonal antibody OKT10, which recognizes the majority of LGL in the peripheral blood, were not significantly altered by cryopreservation. Cryopreserved cells proved to be excellent controls for determining the day-to-day variability of the NK assay and for selecting optimum conditions for this test in the clinical immunology laboratory.  相似文献   

9.
Studies of the immune response of patients following major injury have identified significant abnormalities, some of which may be due to the effects of endotoxin. To evaluate the effect of endotoxin on the immune system without conflicting variables, we studied 18 normal, healthy male volunteers each on two occasions. In one study,Escherichia coli endotoxin was administered intravenously at a dose of 4 ng/kg. In the other, saline was given. Blood for immune function studies was obtained at either 0, 4, or 24 hr (seven volunteers), 0, 1, and 4 hr (five volunteers), or 0, 4, and 6 hr (six volunteers) postinfusion. Peripheral blood mononuclear cells (PBMC) were isolated and adjusted to the same concentration. Measurements following endotoxin infusion were compared with those of the same volunteers following saline infusion and with those from normal ambulatory laboratory volunteers. Interleukin 1 (IL-1) production by adherent cells was significantly reduced at 1 hr post endotoxin infusion. Significant decreases in number of mononuclear cells, response to phytohemagglutinin (PHA), and production of IL-2 and IL-1 were observed by 4 hr after endotoxin infusion. No significant changes in percentages of monocytes, lymphocytes, or CD3, CD4, or CD8 lymphocytes were observed at any time. By 24 hr postinfusion all values had returned to normal or, in some cases, supranormal levels. Response to PHA by PBMC from volunteers 4 hr following endotoxin was completely restored byin vitro addition of recombinant human IL-2 but was only marginally improved by IL-1.In vitro addition of indomethacin to PBMC cultures responding to PHA reduced the suppression observed afterin vivo endotoxin but also was not as effective as IL-2. In a fourth study, seven volunteers were treated as above either with two doses (800 mg each) of the cyclooxygenase inhibitor ibuprofen before endotoxin infusion or with ibuprofen alone. Ibuprofen pretreatment completely restored the PBMC response to PHA to normal and caused a significant decrease in the endotoxin-induced suppression of IL-2 production. However, the decrease in circulating PBMC number and adherent cell secretion of IL-1 was not affected by inhibition of the cyclooxygenase pathway. These results suggest that endotoxin has immunomodulatory effects on both adherent mononuclear-cell and T-lymphocyte function and that more than one mechanism is involved.Abbreviations used IL interleukin - PBMC peripheral blood mononuclear cells - PMN polymorphonuclear neutrophils - PGE prostaglandin E2 - CD cluster designation - TNF tumor necrosis factor - PHA phytohemagglutinin - Con A concanavalin A - LPS lipopolysaccharide - MEM minimal essential medium - FCS fetal calf serum - CRC Clinical Research Center - 3H-Tdr tritiated thymidine - rHU recombinant human - TCGF T-cell growth factor - ELISA enzyme-linked immunosorbent assay - PBS phosphate-buffered saline - Ig immunoglobulin - TGF transforming growth factor Partial publication of these data has been made as follows: Lymphokine research 6:A1518, 1987; Surgical Forum 38:98, 1987; and inImmune Consequences of Trauma, Shock and Sepsis, E Faist, J Ninnemann, D Green (eds). Berlin, Springer-Verlag, 1989  相似文献   

10.
The influence of the early social rearing environment on blood cellular immunity was investigated in the male offspring of Long-Evans rats. Sons of females housed in pair groups (P-males) and sons of females living in a mixed sex colony (C-males) were studied. After weaning at the age of 21 days, offspring were housed individually to ensure identical experiences until the age of 100 days when immunological assessments were conducted. C-males had significantly higher numbers of blood CD4 and CD8 T cells as well as higher numbers of granulocytes and monocytes than P-males. In contrast, the number of B cells and NK cells was similar in P- and C-males. T-cell responsiveness to ConA, determined in the peripheral blood mononuclear cells and whole blood assays, did not differ significantly between the two groups. The study indicates that the early social environment affects numbers and proportions of many blood immune cell subsets in later life.  相似文献   

11.
NK cells play an important role in tumor immunosurveillance and largely contribute to the therapeutic success of anti-tumor antibodies like Rituximab. Here, we studied the role of the TNF family member 4-1BB ligand (4-1BBL) during the interaction of NK cells with chronic lymphocytic leukemia (CLL) cells. 4-1BBL was highly expressed on patient B-CLL cells in all 56 investigated cases. Signaling via 4-1BBL following interaction with 4-1BB, which was detected on NK cells of CLL patients but not healthy individuals, led to the release of immunoregulatory cytokines including TNF by CLL cells. CLL patient sera contained elevated levels of TNF and induced 4-1BB upregulation on NK cells, which in turn impaired direct and Rituximab-induced NK-cell reactivity against 4-1BBL-expressing targets. NK-cell reactivity was not only enhanced by blocking the interaction of NK cell-expressed 4-1BB with 4-1BBL expressed by CLL cells, but also by preventing 4-1BB upregulation on NK cells via neutralization of TNF in patient serum with Infliximab. Our data indicate that 4-1BBL mediates NK-cell immunosubversion in CLL, and thus might contribute to the reportedly compromised efficacy of Rituximab to induce NK-cell reactivity in the disease, and that TNF neutralization may serve to enhance the efficacy of Rituximab treatment in CLL.  相似文献   

12.
Studies of tuberculosis have suggested a shift in dominance from a T helper type 1 (Th1) towards a Th2 immune response that is associated with suppressed cell-mediated immune (CMI) responses and increased humoral responses as the disease progresses. In this study a natural host disease model was used to investigate the balance of the evolving immune response towards Mycobacterium bovis infection in cattle with respect to pathogenesis. Cytokine analysis of CD4 T-cell clones derived from M. bovis-infected animals gave some indication that there was a possible relationship between enhanced pathogenesis and an increased ratio of Th0 [interleukin-4-positive/interferon-gamma-positive (IL-4(+)/IFN-gamma(+))] clones to Th1 (IFN-gamma(+)) clones. All animals developed strong antimycobacterial CMI responses, but depressed cellular responses were evident as the disease progressed, with the IFN-gamma test failing to give consistently positive results in the latter stages. Furthermore, a stronger Th0 immune bias, depressed in vitro CMI responses, elevated levels of IL-10 expression and enhanced humoral responses were also associated with increased pathology. In minimal disease, however, a strong Th1 immune bias was maintained and an anti-M. bovis humoral response failed to develop. It was also seen that the level of the anti-M. bovis immunoglobulin G1 (IgG1) isotype antibody responses correlated with the pathology scores, whereas CMI responses did not have as strong a relationship with the development of pathology. Therefore, the development and maintenance of a Th1 IFN-gamma response is associated with a greater control of M. bovis infection. Animals progressing from a Th1-biased to a Th0-biased immune response developed more extensive pathology and performed less well in CMI-based diagnostic tests but developed strong IgG1 humoral responses.  相似文献   

13.
Peripheral blood lymphocytes (PBL) were obtained from five patients with the acquired immune deficiency syndrome (AIDS), six homosexual males with lymphadenopathy, and five normal heterosexual controls. Modulation of virus-specific immunity was assayedin vitro by measuring the lymphocyte blastogenic response and the production of lymphokine (leukocyte inhibition factor; LIF) by PBL stimulated with herpes simplex virus (HSV) or cytomegalovirus (CMV) antigens in the presence or absence of interleukin-1 (IL-1) and interleukin-2 (IL-2). PBL from the control and lymphadenopathy subjects responded to both antigens in the lymphocyte transformation assay (LT) measured on day 7, and the responses were significantly enhanced in cultures grown in the presence of antigen and IL-2 (1 U/ml). PBL from the AIDS patients were unresponsive, but responsiveness was restored by the addition of IL-2. The addition of IL-1 (0.02 µg/ml) to antigen-stimulated PBL cultures failed to enhance the proliferative responses in all three study groups. LIF production was assayed in the supernatants from day 1 PBL cultures. LIF was not produced by PBL from AIDS patients grown in the presence of viral antigens, whereas three of five patients from the lymphadenopathy group, and three of five control subjects gave rise to positive responses. The addition of IL-1 to the antigenstimulated cultures enhanced LIF production in the control and lymphadenopathy groups but not in the AIDS patients. The addition of IL-2 did not modulate LIF production by antigen-stimulated PBL from the control oR AIDS patients while suppressing the LIF response of the similarly stimulated PBL from the lymphadenopathy patients.  相似文献   

14.
An intravenous administration of a high‐dose antigen (Ag) can induce immune tolerance and suppress the immune response, but the mechanism remains unclear. We recently proved that a combined i.v. administration of OVA and IL‐2‐anti‐IL‐2 Ab immune complexes (IL‐2 ICs) efficiently expands OVA‐specific Treg cells in the thymus and induces their migration into peripheral blood, by using OVA‐specific TCR Tg‐expressing DO11.10 mice. Here, we demonstrate that the expanded OVA‐specific Treg cells rapidly move into the air pouch after OVA injection in DO11.10 mice. The migration was inhibited by blocking the axis of a chemokine receptor, CCR2. Moreover, prior treatment with OVA and IL‐2 ICs enhanced OVA‐specific Treg‐cell migration and inhibited OVA‐induced delayed‐type hypersensitivity (DTH) reactions in the skin of BM chimeric mice with 15% of T cells expressing OVA‐specific TCR. Blocking the CCR2 axis reversed this suppression of DTH in these mice. Furthermore, prior treatment with OVA and IL‐2 ICs effectively reduced DTH reactions even in WT mice possessing only a very small population of OVA‐specific T cells. Thus, the treatment with Ag and IL‐2 ICs can efficiently expand Ag‐specific Treg cells with the capacity to migrate and reduce localized immune responses.  相似文献   

15.
目的:观察不同氧浓度环境下不同时间处理对大脑皮层细胞分泌脑源性神经生长因子(BDNF)及表达BDNF mRNA的影响。方法:原代培养SD大鼠大脑皮层细胞,5 d后将低氧组细胞转移至低氧工作站,在1%和4%氧浓度环境下分别处理3 h和6 h,其相应的常氧对照组细胞则继续放置于CO2孵箱中。ELISA法检测细胞培养液中BDNF蛋白含量;qPCR法检测细胞内BDNF mRNA表达水平。结果:与对照组相比,4%和1%氧浓度环境3 h组细胞BDNF mRNA及蛋白表达无明显变化(P>0.05),但均有增加趋势;而6 h组均引起BDNF mR-NA及蛋白表达明显增高(P<0.05)。结论:低氧可诱导大鼠大脑皮层细胞的BDNF分泌和BDNF mRNA表达增加,且皮层细胞的反应性与低氧浓度和低氧刺激时间有关。  相似文献   

16.
17.
Human lymphocyte subpopulations (B cells, B1, B2, T1, T2, T3, and T4 cells; our denomination) have been previously identified and isolated by bacterial adherence and functional differences between them have been demonstrated. Here we examined the binding properties of Salmonella schottmulleri to human lymphocytes in peripheral blood smears and found that it binds to more lymphocyte subpopulations, namely B, T1, T2 and T3 cells, than any bacteria previously tested. Thus, using only four bacteria: Salmonella schottmulleri, Brucella melitensis, Arizona hinshawii and Bacillus globigii we identified in blood smears B cells, two B and four T cell subpopulations. When we used gelatin-coupled monolayers of Sal. schottmulleri to isolate lymphocyte subpopulations, we showed that the nonadherent (T4) cells could be efficiently separated from the adherent cells. Furthermore, we tested the isolated subpopulations for natural killing (NK) activity and for antibody-dependent cell-mediated cytotoxicity (ADCC). Using both NK and ADCC assays, we observed a significantly higher cytotoxic activity in the nonadherent cell population than in the unseparated or adherent cell populations. Also the nonadherent cells contained most of the lymphocytes that have receptors for the Fc portion of IgG and those cells described as large granular lymphocytes. We concluded that Sal. schottmulleri is a valuable new reagent for the identification and separation of human lymphocyte subpopulations.  相似文献   

18.
Nano- and microparticles are promising carrier systems for oral delivery of drugs or vaccines, particularly in fish aquaculture. However, the mechanisms of uptake, trans-epithelial transport and immune response to nano/micrometer sized particles, or microorganisms such as bacteria are poorly understood in fish. Here, adult zebrafish were used to study the uptake of different nano- and microparticles and the pathogenic bacteria Mycobacterium marinum in the intestine, and their interactions with epithelial cells and the mucosal immune system. Fluorescent particles or bacteria were delivered directly into the adult zebrafish intestine by oral intubation and their localization was imaged in intestine, liver and spleen sections. Zebrafish do not appear to have M-cells, but both nanoparticles and bacteria were rapidly taken up in the intestine and transported to the liver and spleen. In each tissue, both bacteria and particles largely localized to leukocytes, presumably macrophages.  相似文献   

19.
It has recently been reported that liposomes containing membrane components from cytolytic T-cell (TC) clones could transfer lytic activity to noncytolytic T- and B-cell lines, strongly suggesting that TC possess membrane-associated molecules which noncytolytic lymphocytes lack and which play a critical role in the lytic mechanism. It was thus of interest to compare the membrane-associated proteins from TC-lines to those of noncytolytic helper T-cell (TH) lines to determine whether any membrane-associated proteins unique to TC could be identified. Cells from three TC-lines and four TH-lines were internally labelled with [35S]methionine and then disrupted by hypotonic lysis. Low-density (plasma membrane enriched) and high-density (endoplasmic reticulum enriched) membrane fractions were isolated from each cloned cell line and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. Two proteins were identified which were prominent in the membrane fractions from each of the three TC-lines but not in the membrane fractions from any of the four TH-lines. One of these, p215, migrated as a broad band with an apparent mol. wt of 215,000. The other, p24, migrated as a sharp band, or tightly spaced doublet, with an apparent mol. wt of 24,000. Immunoprecipitation studies using monoclonal antibodies to T200, LFA-1, Thy 1 and Lyt 2 suggested that p215 was a variant of T200 found on TC-lines but not on TH-lines. Treatment of solubilized membrane proteins from TH-lines with anti-T200 precipitated a 185-kD protein seen on each of the TH-lines but on none of the TC-lines. In contrast, p24 was not precipitated by any of these monoclonal antibodies. It therefore appears that p24 represents a previously unidentified protein which is strongly expressed by TC but not by TH and is thus deserving of further study as to its functional significance.  相似文献   

20.
《Human immunology》2022,83(1):86-98
The global outbreak of coronavirus-2019 (COVID-19) still claims more lives daily around the world due to the lack of a definitive treatment and the rapid tendency of virus to mutate, which even jeopardizes vaccination efficacy. At the forefront battle against SARS-CoV-2, an effective innate response to the infection has a pivotal role in the initial control and treatment of disease. However, SARS-CoV-2 subtly interrupts the equations of immune responses, disrupting the cytolytic antiviral effects of NK cells, while seriously activating infected macrophages and other immune cells to induce an unleashed “cytokine storm”, a dangerous and uncontrollable inflammatory response causing life-threatening symptoms in patients. Notably, the NK cell exhaustion with ineffective cytolytic function against the sources of exaggerated cytokine release, acts as an Achilles’ heel which exacerbates the severity of COVID-19. Given this, approaches that improve NK cell cytotoxicity may benefit treatment protocols. As a suggestion, adoptive transfer of NK or CAR-NK cells with proper cytotolytic potentials and the lowest capacity of cytokine-release (for example CD56dim NK cells brightly express activating receptors), to severe COVID-19 patients may provide an effective cure especially in cases suffering from cytokine storms. More intriguingly, the ongoing evidence for persistent clonal expansion of NK memory cells characterized by an activating phenotype in response to viral infections, can benefit the future studies on vaccine development and adoptive NK cell therapy in COVID-19. Whether vaccinated volunteers or recovered patients can also be considered as suitable candidates for cell donation could be the subject of future research.  相似文献   

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