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1.
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Innate and type 1 cell-mediated cytotoxic immunity function as important extracellular control mechanisms that maintain cellular homeostasis. Interleukin-12 (IL12) is an important cytokine that links innate immunity with type 1 cell-mediated cytotoxic immunity. We recently observed in vitro that tumor-derived Wnt-inducible signaling protein-1 (WISP1) exerts paracrine action to suppress IL12 signaling. The objective of this retrospective study was three fold: 1) to determine whether a gene signature associated with type 1 cell-mediated cytotoxic immunity was correlated with overall survival, 2) to determine whether WISP1 expression is increased in invasive breast cancer, and 3) to determine whether a gene signature consistent with inhibition of IL12 signaling correlates with WISP1 expression. Clinical information and mRNA expression for genes associated with anti-tumor immunity were obtained from the invasive breast cancer arm of the Cancer Genome Atlas study. Patient cohorts were identified using hierarchical clustering. The immune signatures associated with the patient cohorts were interpreted using model-based inference of immune polarization. Reverse phase protein array, tissue microarray, and quantitative flow cytometry in breast cancer cell lines were used to validate observed differences in gene expression. We found that type 1 cell-mediated cytotoxic immunity was correlated with increased survival in patients with invasive breast cancer, especially in patients with invasive triple negative breast cancer. Oncogenic transformation in invasive breast cancer was associated with an increase in WISP1. The gene expression signature in invasive breast cancer was consistent with WISP1 as a paracrine inhibitor of type 1 cell-mediated immunity through inhibiting IL12 signaling and promoting type 2 immunity. Moreover, model-based inference helped identify appropriate immune signatures that can be used as design constraints in genetically engineering better pre-clinical models of breast cancer.  相似文献   

3.
Amphotericin R (AmB) or its methyl ester (AME) are potent stimulants of humoral and cell-mediated immunity in mice. When AME is injected simultaneously with antigen, it augments humoral immunity by expansion of the primary as well as the memory B cell pool. The most consistent and dramatic effect of amphotericin on humoral immunity is the enhancement of secondary IgG responses. This effect on the IgM-IgG switch mechanism depends on T cells and is reduced following thymectomy on adult mice. The route and timing of amphotericin administration also have dramatic quantitative, effects on immunopotentiation. Neither polyclonal B cell activation nor stimulation of antigen uptake in vitro by peritoneal macrophages was observed following intraperitoneal injection of AME. A tentative hypothesis is that antigen-stimulated T cells are important sites of the immunostimulant effects of AME on murine immune responses.  相似文献   

4.
NK cells are a relatively rare cell population in peripheral lymphoid organs but are abundant in the liver, raising questions as to their function in immune responses to infections of this organ. To investigate this, cell-mediated immunity to viral liver infection induced by a type 5, replication-defective, adenovirus was examined. It is shown that NK cells in the absence of T cells cause hepatocyte apoptosis in virus-infected livers associated with an increase in liver enzymes in the serum. Concomitantly, NK cells induce production of IFN-gamma, inhibitable by their elimination before infection. NK cells are shown to be necessary for optimal priming of virus-specific T cells, assessed by delayed-type hypersensitivity response and CTL activity, consistent with their ability to secrete IFN-gamma. The conclusion is drawn that NK cells mediate two important functions in the liver: they induce cell death in the infected organ and concomitantly stimulate the induction of T cell-mediated immunity by release of IFN-gamma.  相似文献   

5.
The increased number of dendritic cells (DCs) inside lymphoid tissue may contribute to the enhanced priming of lymphocytes. The homeostasis of splenic DCs has mostly been attributed to their migration to the spleen via the chemokine microenvironment induced by lymphotoxin beta receptor (LTbetaR) signaling on splenic stromal cells. In this study we show that the lack of direct LTbetaR signaling on DCs is associated with the reduction of the number of DCs in the spleen independently of chemokine gradients. LTbetaR-/- mice have reduced DCs and reduced BrdU incorporation on DCs, and fewer DCs from LTbetaR-/- mice are detected in the spleen. Furthermore, increased expression of LIGHT (homologous to lymphotoxin, exhibits inducible expression, competes with herpesvirus glycoprotein D for herpes virus entry mediator on T cells) on T cells, a member of the TNF family (TNFSF14) and a ligand for LTbetaR, could dramatically increase the number of T cells and DCs, which leads to severe autoimmune diseases in a LTbetaR-dependent fashion. In vitro, LIGHT could directly promote accumulation of bone marrow-derived DCs. Furthermore, intratumor expression of LIGHT can dramatically expand DCs in situ, and inoculation of DCs into tumor tissues enhanced tumor immunity. Therefore, LTbetaR signaling on DCs is required for their homeostasis during physiology and pathological conditions, and increased LIGHT-LTbetaR interaction could stimulate DC expansion for T cell-mediated immunity.  相似文献   

6.
Acquired immunity to murine Chlamydia trachomatis genital tract reinfection has long been assumed to be solely dependent on cell-mediated immunity. However, in this study, we identify a previously unrecognized protective role for Ab. Immunity develops in Ab-deficient mice following the resolution of primary chlamydial genital infection. Subsequent depletion of CD4+ T cells, but not CD8+ T cells, in those immune Ab-deficient mice before secondary infectious challenge, resulted in an infection that did not resolve. Passive immunization with immune (convalescent) serum conferred a marked level of protective immunity to reinfection, which was characterized by a striking decrease in bacterial shedding, from >100,000 inclusion forming units to fewer than 10 inclusion forming units, and a shortened duration of infection. Furthermore, mAbs to the chlamydial major outer membrane protein and LPS conferred significant levels of immunity to reinfection and reduced chlamydial shedding by >100-fold. Anti-heat shock protein 60 mAb had no protective effect. In contrast to the marked protective efficacy of immune serum on reinfection, the course of primary infection was essentially unaltered by the passive transfer of immune serum. Our results convincingly demonstrate that Abs contribute importantly to immunity to chlamydial genital tract reinfection, and that Ab-mediated protection is highly dependent on CD4+ T cell-mediated adaptive changes that occur in the local genital tract tissues during primary infection. These results impact our understanding of immunity to chlamydial genital infection and may provide important insight into vaccine development.  相似文献   

7.
Immunization of DBA/1 mice with type II collagen resulted in typical and progressive arthritis, which is associated with the production of high titer of anti-collagen antibody and the induction of cell-mediated immunity as exemplified by delayed type hypersensitivity response as well as lymphokine production. In contrast, administration of heat-denatured collagen into DBA/1 mice failed to induce the arthritis. These mice produced only marginal antibody, whereas they developed comparable cell-mediated immunity to that induced by immunization with native collagen, and therefore the inoculation of heat-denatured collagen provided the regimen capable of inducing preferentially cell-mediated immunity without the generation of high level of antibody. Inasmuch as administration of antibody induced only marginal and transient joint swelling not associated with typical histologic lesion, the synergistic effect of humoral and cell-mediated immunities was investigated using antibody preparation and the regimen to induce selectively cell-mediated immunity. The results demonstrate that administration of antibody into DBA/1 mice pre-sensitized with heat-denatured collagen resulted in potent and progressive arthritis. Such synergy was further confirmed by the induction of arthritis in T cell-depleted DBA/1 mice that had been adoptively transferred with antibody and lymphoid cells from heat-denatured collagen-sensitized mice. Moreover, it was revealed that the nature of cells capable of transferring cell-mediated immunity was of Thy-1+ and L3T4+ Lyt-2-. These results indicate that anti-collagen antibody and L3T4+ T cell-mediated cellular immunity are crucially required for the perpetuated development of type II collagen-induced arthritis.  相似文献   

8.
The in vivo induction of T cell-mediated immunity was studied by infecting mice with two genetically closely related mutants from Listeria monocytogenes, differing only with respect to the secretion of an active SH-dependent hemolysin. It is shown that even minute doses of hemolytic bacteria capable of growing in host tissues easily induced the expression of T cell-mediated immunity, as estimated by the level of delayed sensitivity, adoptive protection and long-lasting immunological memory. On the contrary, nonhemolytic bacteria unable to multiply in host tissues totally failed to initiate the expression of T cell-mediated immunity in vivo. This failure was even observed when mice were repeatedly infected by high doses of nonhemolytic bacteria, allowing to maintain a significant amount of viable bacteria for several days in host tissues. These results mean that the presence of viable bacteria at a significant level in the host is not sufficient per se to induce detectable T cell clonal expansion in the in vivo setting, implying that the process of bacterial growth inside macrophages is required to initiate in vivo the expression of T cell-mediated immunity.  相似文献   

9.
Thymic expression of self-Ags results in the deletion of high-avidity self-specific T cells, but, at least for certain Ags, a residual population of self-specific T cells with low-affinity TCRs remains after negative selection. Such self-specific T cells are thought to play a role in the induction of T cell-mediated autoimmunity, but may also be used for the induction of antitumor immunity against self-Ags. In this study, we examine the functional competence of a polyclonal population of self-specific CD8+ T cells. We show that low-affinity interactions between TCR and peptide are associated with selective loss of critical T cell functions. Triggering of low levels of IFN-gamma production and cytolytic activity through low-affinity TCRs readily occurs provided high Ag doses are used, but IL-2 production and clonal expansion are severely reduced at all Ag doses. Remarkably, a single peptide variant can form an improved ligand for the highly diverse population of low-avidity self-specific T cells and can improve their proliferative capacity. These data provide insight into the inherent limitations of self-specific T cell responses through low-avidity TCR signals and the effect of modified peptide ligands on self-specific T cell immunity.  相似文献   

10.
Influenza A virus infection of C57BL/6 mice is a well-characterized model for studying CD8+ T cell-mediated immunity. Analysis of primary and secondary responses showed that the liver is highly enriched for CD8+ T cells specific for the immunodominant H2D(b)NP(366-374) (D(b)NP(366)) epitope. Functional analysis established that these liver-derived virus-specific CD8+ T cells are fully competent cytotoxic effectors and IFN-gamma secretors. In addition, flow cytometric analysis of early apoptotic cells showed that these influenza-specific CD8+ T cells from liver are as viable as those in the spleen, bronchoalveolar lavage, mediastinal lymph nodes, or lung. Moreover, cytokine profiles of the influenza-specific CD8+ T cells recovered from different sites were consistent with the bronchoalveolar lavage, rather than liver population, being the most susceptible to activation-induced cell death. Importantly, adoptively transferred influenza virus-specific CD8+ T cells from the liver survived and were readily recalled after virus challenge. Together, these results show clearly that the liver is not a "graveyard" for influenza virus-specific CD8+ T cells.  相似文献   

11.
IFN-gamma-inducible protein 10/CXCL10 is a chemokine associated with type 1 T cell responses, regulating the migration of activated T cells through binding to the CXCR3 receptor. Expression of both CXCL10 and CXCR3 are observed during immunopathological diseases of the CNS, and this receptor/ligand pair is thought to play a central role in regulating T cell-mediated inflammation in this organ site. In this report, we investigated the role of CXCL10 in regulating CD8(+) T cell-mediated inflammation in the virus-infected brain. This was done through analysis of CXCL10-deficient mice infected intracerebrally with lymphocytic choriomeningitis virus, which in normal immunocompetent mice induces a fatal CD8(+) T cell-mediated meningoencephalitis. We found that a normal antiviral CD8(+) T cell response was generated in CXCL10-deficient mice, and that lack of CXCL10 had no influence on the accumulation of mononuclear cells in the cerebrospinal fluid. However, analysis of the susceptibility of CXCL10-deficient mice to lymphocytic choriomeningitis virus-induced meningitis revealed that these mice just like CXCR3-deficient mice were partially resistant to this disease, whereas wild-type mice invariably died. Furthermore, despite marked up-regulation of the two remaining CXCR3 ligands: CXCL9 and 11, we found a reduced accumulation of CD8(+) T cells in the brain parenchyma around the time point when wild-type mice succumb as a result of CD8(+) T cell-mediated inflammation. Thus, taken together these results indicate a central role for CXCL10 in regulating the accumulation of effector T cells at sites of CNS inflammation, with no apparent compensatory effect of other CXCR3 ligands.  相似文献   

12.
We investigated several phenotypic and functional parameters of T cell-mediated immunity in a large series of common variable immunodeficiency (CVID) patients. We demonstrated that the vast majority of CVID patients presented multiple T cell abnormalities intimately related among them, the severity of which was reflected in a parallel loss of CD4+ naive T cells. A strong correlation between the number of CD4+ naive T cells and clinical features was observed, supporting the subgrouping of patients according to their number of naive CD4+ T lymphocytes. A reduced thymic output and disrupted CD4+ and CD8+ TCR repertoires paralleled the contraction of CD4+ naive T cell pools. The evaluation of activation markers and cytokine production indicated a strong T cell activation that was significantly related to the increased levels of T cell turnover and apoptosis. Finally, discrete genetic profiles could be demonstrated in groups of patients showing extremely diverse T cell subset composition and function. Naive CD4+ T cell levels were significantly associated with the switched memory B cell-based classification, although the concordance between the respective subgroups did not exceed 58.8%. In conclusion, our data highlight the key role played by the T cell compartment in the pathogenesis of CVID, pointing to the need to consider this aspect for classification of this disease.  相似文献   

13.
Parasitic infection, nutrition, and immune response   总被引:2,自引:0,他引:2  
Parasites differ enormously in their abilities to evade normal host defenses. Intracellular protozoa are capable of surviving and multiplying within phagocytes and other cells whereas most nematodes do not multiply within the host. Both T lymphocyte-mediated immune responses and antibody production are important in limiting parasite invasion and in eliminating them. Of the nonspecific factors, macrophages, natural killer cells, and nonantibody serum factors can cause damage to parasites. Malnutrition impairs immunity, most notably cell-mediated processes. The number of T lymphocytes is reduced and there are significant alterations in T cell subsets. Mucosal antibody response is blunted, complement activity is decreased, and microbicidal capacity of phagocytes is reduced. Such changes in host resistance are important determinants of the final outcome of host-parasite interactions.  相似文献   

14.
In animals with acute airway inflammation followed by repeated exposure to inhaled Ag, inflammation wanes over time and thus limits the study of chronic airway inflammatory diseases such as asthma. We developed a model of airway inflammation and inhalational exposure to investigate regulatory pathways in the respiratory tract. We show that Th1- and Th2-induced airway inflammation followed by repeated exposure to inhaled Ag leads to a state of immunosuppression. Challenge of these animals with a marked population of TCR transgenic effector Th1 or Th2 cells results in a striking inhibition of inflammation and effector Th cells. In Th2 models, airway hyperresponsiveness, mucus, and eosinophilia are reduced. The inhibitory effects observed are Ag nonspecific, can be induced in lymphocyte-deficient mice, and are associated with a population of TGF-beta1-expressing macrophages. Induction of this pathway may offer potent localized treatment of chronic T cell-mediated respiratory illnesses and provide insights into the development of such diseases.  相似文献   

15.
The pathology of the synovial membrane in rheumatoid arthritis can be characterized by the prominence of two major features which appear to vary independently of one another. These are synovial lining-cell proliferation and infiltration with inflammatory cells, predominantly lymphocytes. In a series of 42 synovectomies from 36 patients it has been shown that extensive joint damage is associated with a synovial picture of marked lining-cell proliferation and a sparsity of lymphocytes. Cases with heavy lymphocyte infiltration tend to show less damage to articular cartilage and bone despite a similar duration of disease. These results have been compared with the picture in leprosy, where a similar pathological spectrum is associated with changes in cell-mediated immunity necessary for the control of infection.  相似文献   

16.
This study employed an experimental mouse model of Mycobacterium tuberculosis infection to investigate the effects of aging on T cell-mediated protective cellular immunity. It was found that although mice of 3 to 18 mo of age were fully resistant to a standard immunizing dose of Mycobacterium tuberculosis, progressive mortality was observed in old (24 to 28 mo) mice. Death of these older animals was associated with an inability to contain or to eliminate the mycobacterial infection in the spleen and liver, and with an inability to prevent the progressive growth of the infection in the lungs. It was then revealed by the use of reciprocal passive cell transfer experiments that the age-related susceptibility of old mice reflected an inability to generate mediator protective T lymphocytes in response to the infection. In contrast, no evidence was obtained to indicate any defect at the effector cell (macrophage) level, as evidenced primarily by the finding that immune T cells from young mice conferred equivalent levels of immunity upon both old and young recipients. The results suggest therefore that T cell-mediated immunity undergoes an age-related decline in terms of its ability to respond to infection with Mycobacterium tuberculosis.  相似文献   

17.
It is unclear whether the presence of interleukin-2 soluble receptor alpha (IL-2 sRalpha) in the serum of colorectal cancer patients is solely due to T cell activation. In this study, we therefore investigated whether T cell activation, indicated by the up-regulation of the CD25 and HLA-DR markers, or cell-mediated immunity (CMI) were associated with increased serum levels of IL-2 sRalpha in patients with advanced colorectal carcinoma. The levels of serum IL-2 sRalpha and the proportion of T cells expressing HLA-DR (DR(+) T cells) were measured as markers for chronic activation. CMI was assessed by delayed-type hypersensitivity reaction (DTH) to intradermal injections of recall antigens. Eighty-seven colorectal liver metastases (CLM) patients and 23 'cancer-free' control subjects were studied. DR(+) T cells were found to be more prevalent ( P<0.0001) in CLM patients (median: 21.1%) than in controls (median: 3.4%), but DR(+) T cell up-regulation was not correlated with serum IL-2 sRalpha levels. CMI positivity was significantly reduced ( P=0.002) in CLM patients compared with controls, and this reduction was significantly associated ( P=0.05) with an increase in the number of DR(+) T cells. Although survival was significantly shorter ( P=0.0003) in patients with increased serum IL-2 sRalpha levels than in subjects with normal levels, no association was found between survival and DR(+) T cell up-regulation. These findings were consistent with the hypothesis of an additional source of serum IL-2 sRalpha other than T cell up-regulation in CLM patients -- either from other immune cells, or from tumour products.  相似文献   

18.
One of the primary assumptions of the immunocompetence handicap hypothesis is that testosterone has an immunosuppressive effect, but conflicting results have been reported in a variety of bird species concerning the effect of testosterone on the humoral and the T cell-mediated components of the immune system. The T cell-mediated component of the immune system is particularly important during the breeding season, because the likelihood of injury during sexual competition is high and T cell-mediated immunity is essential for healing wounds and resisting infection. In this study we examined the effect of experimentally increased levels of testosterone during breeding season on T cell-mediated immunity in male lizards of two Mediterranean lacertid species, Psammodromus algirus and Acanthodactylus erythrurus. The hormonal treatment significantly increased testosterone of the experimental individuals. T cell-mediated responses to phytohemagglutinin stimulation were significantly suppressed in testosterone-treated males of both species. Furthermore, there was a significant negative relationship between individual variability in T cell-mediated responsiveness and plasma testosterone concentration. The present study is the first to demonstrate testosterone-induced suppression of T cell-mediated immunity in lizards.  相似文献   

19.
Immunity induced by Plasmodium vivax infection leads to memory T cell recruitment activated during "relapse" or "re-infection". This study aims to characterise memory T cells in patients with acute or convalescent P. vivax infection. Lymphocytes were collected from patients infected by P. vivax, immune controls and naive controls. The proportion of immature memory T cells, expressing CD45RO(+)CD27(+), and mature cells lacking CD27 was assessed. A statistically significant increase in the median percentage of memory T cell subsets expressing CD4(+) was observed in material from patients with an acute infection compared with that from either naive or immune controls. The high percentage of memory T cells in infected patients was maintained until 60 days post treatment. The immune controls living in a malaria endemic area had a somewhat increased proportion of memory T cell subsets expressing CD8(+). An approximately three-fold increase of these cell types was shown in patients with an acute infection and the level persisted until 60 days post treatment. Phenotypic characterisation of the peripheral lymphocytes during acute infection revealed that a large fraction of the lymphocytes carried the gammadelta phenotypes suggesting a role for these cells in the early response against P. vivax. Very low levels of P. vivax specific antibody were found. This might suggest that cell-mediated immunity may play a greater role in the development of naturally acquired protection against P. vivax infection than humoral immunity. Our results provide further insight into the mechanism of cell-mediated immunity to P. vivax infection that could be important for the future development of a successful vaccine and anti-malarial drug designation.  相似文献   

20.
Neonates are thought to mount less vigorous adaptive immune responses than adults to antigens and infectious agents. This concept has led to a delay in the administration of many currently available vaccines until late infancy or early childhood. It has recently been shown that vaccines composed of plasmid DNA can induce both humoral and cell-mediated antimicrobial immunity when administered within hours of birth. In most of these studies, immune responses were measured weeks or months after the initial vaccination, and it is therefore questionable whether the observed responses were actually the result of priming of splenocytes within the neonatal period. Here we show that DNA vaccination at birth results in the rapid induction of antigen-specific CD8(+) T cells within neonatal life. Analyses of T-cell effector functions critical for the resolution of many viral infections revealed that neonatal and adult CD8(+) T cells produce similar arrays of cytokines. Furthermore, the avidities of neonatal and adult CD8(+) T cells for peptide and the rapidity with which they upregulate cytokine production after recall encounters with antigen are similar. Protective immunity against the arenavirus lymphocytic choriomeningitis virus, which is mediated by CD8(+) cytotoxic T cells, is also rapidly acquired within the neonatal period. Collectively these data imply that, at least in the case of CD8(+) T cells, neonates are not as immunodeficient as previously supposed and that DNA vaccines may be an effective and safe means of providing critical cell-mediated antiviral immunity extremely early in life.  相似文献   

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