Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036690 (sepsis)
 59,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lipopolysaccharide (LPS) causes apoptotic deletion of CD4(+) CD8(+) thymocytes, a phenomenon that has been linked to immune dysfunction and poor survival during sepsis. Given the abundance of thromboxane-prostanoid (TP) receptors in CD4(+) CD8(+) thymocytes and in vitro evidence that thromboxane A(2) (TXA(2)) causes apoptosis of these cells, we tested whether enhanced generation of TXA(2) plays a role in LPS-induced thymocyte apoptosis. Mice injected with 50 micro LPS intraperitoneally displayed a marked increase in generation of TXA(2) and prostaglandin E(2) in the thymus as well as apoptotic deletion of CD4(+) CD8(+) thymocytes. Administration of indomethacin or rofecoxib inhibited prostanoid synthesis but did not affect thymocyte death. In contrast, thymocyte apoptosis in response to LPS was significantly attenuated in TP-deficient mice. These studies indicate that TXA(2) mediates a portion of apoptotic thymocyte death caused by LPS. The absence of an effect of global inhibition of prostanoid synthesis suggests a complex role for prostanoids in this model.
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PMID:Role of thromboxane A2 in the induction of apoptosis of immature thymocytes by lipopolysaccharide. 1608 5

A viral hemorrhagic septicemia virus (VHSV), recombinant glycoprotein vaccine (VHSVg) and a DNA vaccine (pCMV-VHSg) were injected in Japanese flounder (Paralichthys olivaceus). Each fish was injected with 10 microg vaccine dissolved in 50 microl phosphate buffer saline (PBS). One month after the vaccination, the fish were challenged intraperitoneally with either 1 x 10(2) or 1 x 10(3) TCID(50) of virus. Fish that received the VHSg DNA vaccine were highly protected against virus infection over a 21-day observation period, with cumulative mortalities ranging from 4 to 10%. However, the recombinant protein vaccine group appeared to have low survival rates. Using microarray analysis, humoral defense-related genes such as complement component C3, complement regulatory plasma proteins, IgM, IgD, MHC class II-associated invariant chain and CD20 receptor were observed to be up-regulated by the VHSg recombinant protein vaccine at 1 or 21 days post vaccination. On the other hand, cellular defense-related genes such as CD8 alpha chain, T-cell immune regulator, MIP1-alpha and apoptosis-associated protein were not detected. Specific antibodies against VHSVg protein were detected in both vaccinated groups at a titer of 1:40 at 28 days post vaccination.
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PMID:Comparative immune responses in Japanese flounder, Paralichthys olivaceus after vaccination with viral hemorrhagic septicemia virus (VHSV) recombinant glycoprotein and DNA vaccine using a microarray analysis. 1618 91

Lipopolysaccharide (LPS) has been implicated as one of the major cause of Gram-negative bacteria-induced sepsis that are life-threatening syndromes occurring in intensive care unit patients. Many natural products derived from medicinal plants may contain therapeutic values on protecting endotoxemia-induced sepsis by virtue their ability to modulate multiple pro-inflammatory cytokines. In the present study, we show that Salvia miltiorrhiza (SM) BUNGE or Danshen, used in treatment of various systemic and surgical infections in the hospitals of China, was able to block the lethal toxicity of LPS in mice via suppression of TNF-alpha release and protection on liver injury. The ability of SM to suppress LPS-induced TNF-alpha release is further confirmed by in vitro experiments conducted on human peripheral blood leukocytes (PBL) and the RAW 264.7 macrophage cell line. Immunophenotyping by flow cytometry shows improved T-helper cell (CD4) and T-suppressor cells (CD8) ratio in SM-treated PBL and splenocytes of LPS-challenged mice. The drop in plasma glutamate-pyruvate transaminase (GPT) induced by LPS provides evidence that SM can protect hepatic damage. The present study explains some known biological activities of SM, and supports the clinical application of SM in the prevention of inflammatory diseases induced by Gram-negative bacteria.
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PMID:Protection of lethal toxicity of endotoxin by Salvia miltiorrhiza BUNGE is via reduction in tumor necrosis factor alpha release and liver injury. 1654 5

Intercellular adhesion molecule 1 (ICAM-1) plays an important role in the transmigration of polymorphonuclear neutrophils (PMN) in sepsis. Moreover, the transmigration rate of leukocytes from the blood via endothelial adhesion molecules into tissues correlates with the severity of multi organ failure. We examined the effect of the deletion of the ICAM-1 gene in polymicrobial sepsis using a cecal ligation and puncture (CLP) sepsis model in mice. Twenty male ICAM-1 knockout (KO) mice and 20 wild-type (WT) male C57BL/6 mice were studied. CLP was performed. At several time points during a 96-hour postoperative observation period, we measured mortality, body weight, and temperature. The delayed type of hypersensitivity (DTH) reaction was determined by pinna swelling after sensitization with 50 microL of dinitrofluorobenzene (DNFB) 1%. Lymphocyte subpopulations (CD4, CD8, and CD56) and cytokines [tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), interleukin-6 (IL-6), and interleukin-10 (IL-10)] were measured using flow cytometry and ELISA testing, respectively. Also, a histologic examination of the liver and lung was performed. CLP-induced mortality was lower in the ICAM-1 group compared to normal mice (5% vs 45.0%). So were the ratios of lymphocyte subpopulations in the KO versus the WT group [CD4: 16.4 +/- 1.6% vs 25.7 +/- 4.7%; CD8: 18.3 +/- 1.4% vs 34.9 +/- 2.9%; natural killer (NK) cells: 5.6 +/- 0.3% vs 49.5 +/- 0.7%; P < 0.01]. And also the cytokine blood levels of the KO mice were significantly lower versus the WT mice (TNF-alpha: 67.2 +/- 42.2 vs 823.9 +/- 170.5 pg/mL; IL-1beta: 5.9 +/- 0.9 vs 296.2 +/- 66.2 pg/mL; IL-6: 223.1 +/- 48.8 vs 3062.5 +/- 1222.8 pg/mL; IL-10: 34.6 +/- 5.8 vs 1565.6 +/- 448.8 pg/mL; P < 0.01). With respect to the histology, significantly less leukocyte invasion and organ damage (eg, hydropic degeneration) were present in the ICAM-1-/- group compared to controls in liver and lung tissues. The DTH reaction was significantly decreased in ICAM-1-/- mice versus WT mice (0.34 vs 0.41 mm; P < 0.05). Our results demonstrate a significant reduction of mortality after septic challenge in ICAM-1-/- mice compared to normal mice. This is associated with a decrease in lymphocyte subpopulations, cytokine levels, and DTH type 4 reaction, possibly reflecting an overall attenuation of the immune system.
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PMID:Leukocyte-endothelial interactions via ICAM-1 are detrimental in polymicrobial sepsis. 1655 57

The diverse immunostimulatory effects of CpG oligodeoxynucleotides (CpG ODN) have been demonstrated extensively in mice and human. Although the immunoadjuvant effects of CpG ODN in pigs were also studied in several reports, until now, little work has been carried out with regard to their effects on the adaptive immune system of newly weaned piglets. In this study, swine streptococcic septicemia killed vaccine (SSSK vaccine) was used as antigen, we assessed the in vivo immunostimulatory effects of different CpG motifs in newly weaned piglets. The proportion of CD4(+), CD8(+) T lymphocytes subpopulations and proliferation of peripheral blood mononuclear cells (PBMCs), IFN-gamma and IL-6 in serum, and the titre of IgG and IgG2/IgG1 isotype to SSSK vaccine in serum were tested at different time-points. The results suggested that, the CD4(+)/CD8(+) ratio decreased significantly in weaned piglets inoculated with phosphate buffer saline (PBS) alone, however, it was stable in CpG ODN-coinoculated newly weaned piglets. IFN-gamma and IL-6 levels, the titres of specific antibodies IgG, IgG2 and proliferative responses of CpG ODN-coinjected piglets were all significantly higher than those of SSSK vaccine alone or PBS or GpC ODN-coinjected piglets. The porcine-specific ODN-induced responses were stronger in animals injected with human-specific or mouse-specific CpG ODN. These in vivo data demonstrate for the first time that CpG ODN can stimulate adaptive immune system in weaned piglets.
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PMID:In vivo effects of oligodeoxynucleotides containing synthetic immunostimulatory motifs in the immune response to swine streptococcic septicemia vaccine in weaned piglets. 1691 28

Antibody-based approaches to pneumococcal disease may hold promise for immunocompromised patients in whom vaccines are less immunogenic and/or in the context of antimicrobial resistance. Antibody-mediated protection against experimental pneumococcal pneumonia has been shown to depend on immunoregulation, but the relationship between antibody and protection against pneumococcal sepsis and immunoregulation has not been examined. Similarly, the requirement for B and T cells for antibody efficacy is not known. In this study, we determined the efficacy of the human pneumococcal capsular polysaccharide serotype 3-specific antibody, A7 (immunoglobulin M [IgM]), in secretory IgM (sIgM)(-/-), CD4(-/-), CD8(-/-), muMT(-/-), and SCID mice and investigated its effect on cytokine and chemokine expression in sera and spleens from mice with intact cellular immunity. A7 is known to be protective against systemic infection with serotype 3 and to require complement for efficacy. Compared to that of an isotype control antibody, A7 administration prolonged the survival of mice of each immunodeficient strain and was associated with a significant reduction in CFU in blood, lung, and spleen samples and a significantly reduced level of keratinocyte-derived chemokine (KC), interleukin-6 (IL-6), and macrophage inflammatory protein-2 (MIP-2) expression in normal and sIgM(-/-) mice. Studies with mice treated with penicillin revealed similar reductions in CFU and similar levels of IL-6, KC, or MIP-2 expression in A7- and penicillin-treated mice. These findings demonstrate that natural IgM and B and T cells are dispensable for A7-mediated protection against experimental pneumococcal sepsis and suggest that the efficacy of antibody-mediated protection depends on immunomodulation. Taken together, our data extend the association between antibody-mediated protection and immunomodulation to protection against systemic pneumococcal infection and to a clinically important serotype often responsible for pneumococcal sepsis.
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PMID:A human monoclonal immunoglobulin M reduces bacteremia and inflammation in a mouse model of systemic pneumococcal infection. 1730 Dec 14

Studies have indicated that there is a development of generalized immune dysfunction after septic insult. However, the mechanisms responsible for these changes remain unclear. Recently, accumulating evidence shows that several lymphocyte subpopulations such as NKT-, CD4(+)-Th2-T-, CD8(+)-T-, gammadelta-T-, and CD4+ CD25+ T regulatory cells are capable of actively contributing to the induction of septic immune suppression. Thus, our aim was to investigate the contribution of CD4+ CD25+ cells to the immune dysfunction seen in sepsis. To study this, C57BL/6J, C57BL/6-Il6(tm1Kopf) (interleukin [IL] 6 -/-), and C57BL/6-Il10(tm1Cgn) (IL-10 -/-) mice were subjected to cecal ligation and puncture (CLP) or sham operations. Twenty-four hours later, blood was collected, and splenocytes were isolated. Phenotypic expression of CD4/CD25 (by fluorescence-activated cell sorter), cell proliferation (presented as proliferation index = [with anti-CD3]/[without anti-CD3]), and immune suppressive capacity (by in vitro add-back experiments) were assessed. The results indicate a marked elevation in CD4+ CD25+ cell levels and their proliferation index after sepsis in background mice. CD4+ CD25- cells from sham and CLP mice proliferated equally. However, coculture of CD4+ CD25- with CD4+ CD25+ cells suppressed their proliferation in both sham and CLP mice. Depletion of CD25+ cells in vivo before CLP markedly restored CD4+ CD25- proliferative capacity and Th1 cytokine release while not altering plasma proinflammatory cytokine levels. Subsequently, IL-6 -/- and IL-10 -/- mice were used to elucidate the possible mediator(s) regulating the changes seen after sepsis. Although CD4+ CD25+ cells increased after septic insult in both C57BL/6J and IL-6 -/- mice, this was not observed in IL-10 -/- mice. Similarly, in vitro proliferation studies showed that proliferation index increased in CD4+ CD25+ cells from septic C57BL/6J and IL6 -/- mice, but it remained the same in IL-10 -/- mice. Surprisingly, depletion of CD25+ cells before inducing sepsis did not alter septic mortality. Together, these findings suggest that although CD4+ CD25+ T regulatory cells induced by IL-10 seem to contribute to aspects of sepsis-induced lymphoid immune suppression, the oblation of CD25+ cells does not provide a survival advantage or disadvantage.
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PMID:The contribution of CD4+ CD25+ T-regulatory-cells to immune suppression in sepsis. 1730 5

Polymicrobial sepsis alters the adaptive immune response and induces T cell suppression and Th2 immune polarization. We identify a GR-1(+)CD11b(+) population whose numbers dramatically increase and remain elevated in the spleen, lymph nodes, and bone marrow during polymicrobial sepsis. Phenotypically, these cells are heterogeneous, immature, predominantly myeloid progenitors that express interleukin 10 and several other cytokines and chemokines. Splenic GR-1(+) cells effectively suppress antigen-specific CD8(+) T cell interferon (IFN) gamma production but only modestly suppress antigen-specific and nonspecific CD4(+) T cell proliferation. GR-1(+) cell depletion in vivo prevents both the sepsis-induced augmentation of Th2 cell-dependent and depression of Th1 cell-dependent antibody production. Signaling through MyD88, but not Toll-like receptor 4, TIR domain-containing adaptor-inducing IFN-beta, or the IFN-alpha/beta receptor, is required for complete GR-1(+)CD11b(+) expansion. GR-1(+)CD11b(+) cells contribute to sepsis-induced T cell suppression and preferential Th2 polarization.
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PMID:MyD88-dependent expansion of an immature GR-1(+)CD11b(+) population induces T cell suppression and Th2 polarization in sepsis. 1754 19

Although studies blocking the Fas pathway indicate it can decrease organ damage while improving septic (cecal ligation and puncture, CLP) mouse survival, little is known about how Fas-Fas ligand (FasL) interactions mediate this protection at the tissue level. Here, we report that although Fas expression on splenocytes and hepatocytes is up-regulated by CLP and is inhibited by in vivo short interfering RNA, FasL as well as the frequency of CD8(+) T cells are differentially altered by sepsis in the spleen (no change in FasL, decreased percentage of CD8(+) and CD4(+) T cells) versus the liver (increased FasL expression on CD8(+) T cells and increase in percentage/number). Adoptive transfer of CLP FasL(+/+) versus FasL(-/-) mouse liver CD8(+) T cells to severe combined immunodeficient or RAG1(-/-) recipient mice indicated that these cells could induce inflammation. The FasL-mediated cytotoxic capacity of these septic mouse liver CD8(+) T cells was shown by their ability to damage directly cultured hepatocytes. Finally, although CD8(-/-) mice exhibited a reduction in both CLP-induced liver active caspase-3 staining and blood interleukin-6 levels, only FasL(-/-) (but not CD8(-/-)) protected the septic mouse spleen from increasing apoptosis. Thus, although truncating Fas-FasL signaling ameliorates many untoward effects of sepsis, the pathological mode of action is distinct at the tissue level.
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PMID:CD8+ T cells promote inflammation and apoptosis in the liver after sepsis: role of Fas-FasL. 1759 56

Rebuilding and maintaining immunity are paramount to the success of cancer immunotherapy and hematopoietic stem cell transplantation. If immune surveillance indeed can protect from cancer, the very manifestation of malignancy means that the disease has prevailed over immunity. Yet, often, tumor-specific T cells can be found in cancer patients irrespective of vaccination. Interestingly, patients suffering from malignancy often harbor unexpectedly high levels of immature CD14(+)HLA-DR(-) monocytes, although the abundance of CD4(+) cells, CD8(+) cells and CD4(+)CD25(high) cells may be normal. It is plausible that in cancer such cells suppress T cell function, analogous to CD14(+)HLA-DR(-) cells in sepsis and major trauma, in addition to their likely failure to re-present tumor-associated antigens once dendritic cells have initiated the T cell response. Recent evidence indicates that tumor-borne adenosine, lactate and hypoxia in the tumor environment may modulate tumor-specific immunity to a significant extent, but their effects on myeloid cell function are unclear. Thus, understanding and controlling these factors may appreciably impact the success of rebuilding and maintaining immunity in cancer patients.
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PMID:Rebuilding immunity in cancer patients. 1782 37


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