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Extracellular adenosine triphosphate and adenosine in cancer.

Oncogene. 2010 Jul 26;

Authors: Stagg J, Smyth MJ

Adenosine triphosphate (ATP) is actively released in the extracellular environment in response to tissue damage and cellular stress. Through the activation of P2X and P2Y receptors, extracellular ATP enhances tissue repair, promotes the recruitment of immune phagocytes and dendritic cells, and acts as a co-activator of NLR family, pyrin domain-containing 3 (NLRP3) inflammasomes. The conversion of extracellular ATP to adenosine, in contrast, essentially through the enzymatic activity of the ecto-nucleotidases CD39 and CD73, acts as a negative-feedback mechanism to prevent excessive immune responses. Here we review the effects of extracellular ATP and adenosine on tumorigenesis. First, we summarize the functions of extracellular ATP and adenosine in the context of tumor immunity. Second, we present an overview of the immunosuppressive and pro-angiogenic effects of extracellular adenosine. Third, we present experimental evidence that extracellular ATP and adenosine receptors are expressed by tumor cells and enhance tumor growth. Finally, we discuss recent studies, including our own work, which suggest that therapeutic approaches that promote ATP-mediated activation of inflammasomes, or inhibit the accumulation of tumor-derived extracellular adenosine, may constitute effective new means to induce anticancer activity.Oncogene advance online publication, 26 July 2010; doi:10.1038/onc.2010.292.

PMID: 20661219 [PubMed - as supplied by publisher]

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Exogenous fms-like tyrosine kinase 3 ligand overrides brain immune privilege and facilitates recognition of a neo-antigen without causing autoimmune neuropathology.

Proc Natl Acad Sci U S A. 2010 Jul 26;

Authors: Larocque D, Sanderson NS, Bergeron J, Curtin JF, Girton J, Wibowo M, Bondale N, Kroeger KM, Yang J, Lacayo LM, Reyes KC, Farrokhi C, Pechnick RN, Castro MG, Lowenstein PR

Soluble antigens diffuse out of the brain and can thus stimulate a systemic immune response, whereas particulate antigens (from infectious agents or tumor cells) remain within brain tissue, thus failing to stimulate a systemic immune response. Immune privilege describes how the immune system responds to particulate antigens localized selectively within the brain parenchyma. We believe this immune privilege is caused by the absence of antigen presenting dendritic cells from the brain. We tested the prediction that expression of fms-like tyrosine kinase ligand 3 (Flt3L) in the brain will recruit dendritic cells and induce a systemic immune response against exogenous influenza hemagglutinin in BALB/c mice. Coexpression of Flt3L with HA in the brain parenchyma induced a robust systemic anti-HA immune response, and a small response against myelin basic protein and proteolipid protein epitopes. Depletion of CD4(+)CD25+ regulatory T cells (Tregs) enhanced both responses. To investigate the autoimmune impact of these immune responses, we characterized the neuropathological and behavioral consequences of intraparenchymal injections of Flt3L and HA in BALB/c and C57BL/6 mice. T cell infiltration in the forebrain was time and strain dependent, and increased in animals treated with Flt3L and depleted of Tregs; however, we failed to detect widespread defects in myelination throughout the forebrain or spinal cord. Results of behavioral tests were all normal. These results demonstrate that Flt3L overcomes the brain's immune privilege, and supports the clinical development of Flt3L as an adjuvant to stimulate clinically effective immune responses against brain neo-antigens, for example, those associated with brain tumors.

PMID: 20660723 [PubMed - as supplied by publisher]

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Retraction: Activation of Discoidin Domain Receptor 1 Facilitates the Maturation of Human Monocyte-Derived Dendritic Cells Through the TNF Receptor Associated Factor 6/TGF-{beta}-Activated Protein Kinase 1 Binding Protein 1{beta}/p38{alpha} Mitogen-Activated Protein Kinase Signaling Cascade.

J Immunol. 2010 Aug 1;185(3):1984

Authors: Yoshimura T

PMID: 20660362 [PubMed - in process]

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The phosphatidylserine receptors, T cell immunoglobulin mucin proteins 3 and 4, are markers of histiocytic sarcoma and other histiocytic and dendritic cell neoplasms.

Hum Pathol. 2010 Jul 23;

Authors: Dorfman DM, Hornick JL, Shahsafaei A, Freeman GJ

The T cell immunoglobulin mucin (TIM) proteins are a family of cell surface phosphatidyserine receptors that are important for the recognition and phagocytosis of apoptotic cells. Because TIM-4 is expressed by macrophages and dendritic cells in human tissue, we examined its expression in a range of histiocytic and dendritic cell neoplasms and found moderate to strong immunohistochemical staining in cases of juvenile xanthogranuloma and histiocytic sarcoma, and lower level staining in interdigitating dendritic cell sarcoma, Langerhans cell histiocytosis, acute monocytic leukemia (leukemia cutis), and blastic plasmacytoid dendritic cell neoplasm (hematodermic tumor). TIM-3 was first described on activated T(H)1 cells but was recently shown to also be a phosphatidylserine receptor and mediate phagocytosis. We found TIM-3 was expressed by peritoneal macrophages, monocytes and splenic dendritic cells. We found that it, like TIM-4, is expressed in a range of histiocytic and dendritic cell neoplasms, typically with strong immunohistochemical staining. Cases of diffuse large B cell lymphoma, anaplastic large cell lymphoma, metastatic malignant melanoma, and metastatic poorly differentiated carcinoma generally exhibited negative to minimal heterogenous staining for TIM-4 and TIM-3. We conclude that histiocytic and dendritic cell neoplasms consistently express TIM-3 and TIM-4 and that these molecules are new markers of neoplasms derived from histiocytic and dendritic cells.

PMID: 20656318 [PubMed - as supplied by publisher]

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CpG-C immunotherapeutic efficacy is jeopardized by ongoing exposure to stress: Potential implications for clinical use.

Brain Behav Immun. 2010 Jul 22;

Authors: Goldfarb Y, Levi B, Sorski L, Frenkel D, Ben-Eliyahu S

Bi-directional influences between stress hormones and immune responses have been repeatedly documented, however, in the clinical setting they are rarely considered when immunotherapeutic approaches are used or studied in patients. As some immunotherapeutic treatments have shown great potential in animal models but have had limited success in patients, we hypothesize that on-going psychological and physiological stress responses in patients, which do not characterize the setting of animal studies, contribute to this discrepancy. In the current study we examined the interaction between on-going water stress and CpG-C immunotherapy to determine whether stress that precedes immunotherapy can modulate the efficacy of CpG-C immunostimulation. C57BL/6 mice were exposed to water stress or served as controls. Two hrs following the commencement of the stress protocol animals were injected with CpG-C, non-CpG, or PBS, and sacrificed 1, 4 or 12hrs thereafter. We found that in CpG-C-treated animals stress eliminated the elevation of plasma IL-12, and synergistically elevated corticosterone levels. Furthermore, stress markedly reduced the total number of myeloid (33D1(+)), plasmacytoid (mPDCA-1(+)) and plasmacytoid-derived (33D1(+)mPDCA-1(+)) dendritic cells in CpG-C-treated animals, as well as the numbers of these cell sub-types expressing CD11b, CD80 and CD69. These changes were more dramatic in the blood than in the spleen. Overall, these findings indicate that under no-stress conditions CpG-C induces a robust immune response, which is significantly diminished when immunostimulation is attempted during on-going stress. If these findings hold in humans, potential prophylactic treatments should be found to limit the deleterious effects of on-going stress on the efficacy of immunotherapy.

PMID: 20656015 [PubMed - as supplied by publisher]

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First-line chemoimmunotherapy in metastatic breast carcinoma: combination of paclitaxel and IMP321 (LAG-3Ig) enhances immune responses and antitumor activity.

J Transl Med. 2010 Jul 23;8(1):71

Authors: Brignone C, Gutierrez M, Mefti F, Brain E, Jarcau R, Cvitkovic F, Bousetta N, Medioni J, Gligorov J, Grygar C, Marcu M, Triebel F

ABSTRACT: BACKGROUND: IMP321 is a recombinant soluble LAG-3Ig fusion protein that binds to MHC class II with high avidity and mediates APC and then antigen-experienced memory CD8+ T cell activation. We report clinical and biological results of a phase I/II in patients with metastatic breast carcinoma (MBC) receiving first-line paclitaxel weekly, 3 weeks out of 4. METHODS: MBC patients were administered one dose of IMP321 s.c. every two weeks for a total of 24 weeks (12 injections). The repeated single doses were administered the day after chemotherapy at D2 and D16 of the 28-day cycles of paclitaxel (80 mg/m2 at D1, D8 and D15, for 6 cycles). Blood samples were taken 13 days after the sixth and the twelfth IMP321 injections to determine sustained APC, NK and memory CD8 T cell responses. RESULTS: Thirty MBC patients received IMP321 in three cohorts (doses: 0.25, 1.25 and 6.25 mg). IMP321 induced both a sustained increase in the number and activation of APC (monocytes and dendritic cells) and an increase in the percentage of NK and long-lived cytotoxic effector-memory CD8 T cells. Clinical benefit was observed for 90 % of patients with only 3 progressors at 6 months. Also, the objective tumor response rate of 50 % compared favorably to the 25 % rate reported in the historical control group. CONCLUSIONS: The absence of toxicity and the demonstration of activity strongly support the future development of this agent for clinical use in combined first-line regimens. Trial registration: ClinicalTrials.gov NCT00349934.

PMID: 20653948 [PubMed - as supplied by publisher]

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Plasticity in programming of effector and memory CD8 T-cell formation.

Immunol Rev. 2010 May;235(1):190-205

Authors: Arens R, Schoenberger SP

CD8(+) T cells (also called cytotoxic T lymphocytes) play a major role in protective immunity against many infectious pathogens and can eradicate malignant cells. The path from naive precursor to effector and memory CD8(+) T-cell development begins with interactions between matured antigen-bearing dendritic cells (DCs) and antigen-specific naive T-cell clonal precursors. By integrating differences in antigenic, costimulatory, and inflammatory signals, a developmental program is established that governs many key parameters associated with the ensuing response, including the extent and magnitude of clonal expansion, the functional capacities of the effector cells, and the size of the memory pool that survives after the contraction phase. In this review, we discuss the multitude of signals that drive effector and memory CD8(+) T-cell differentiation and how the differences in the nature of these signals contribute to the diversity of CD8(+) T-cell responses.

PMID: 20536564 [PubMed - indexed for MEDLINE]

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TIM genes: a family of cell surface phosphatidylserine receptors that regulate innate and adaptive immunity.

Immunol Rev. 2010 May;235(1):172-89

Authors: Freeman GJ, Casasnovas JM, Umetsu DT, DeKruyff RH

The TIM (T cell/transmembrane, immunoglobulin, and mucin) gene family plays a critical role in regulating immune responses, including allergy, asthma, transplant tolerance, autoimmunity, and the response to viral infections. The unique structure of TIM immunoglobulin variable region domains allows highly specific recognition of phosphatidylserine (PtdSer), exposed on the surface of apoptotic cells. TIM-1, TIM-3, and TIM-4 all recognize PtdSer but differ in expression, suggesting that they have distinct functions in regulating immune responses. TIM-1, an important susceptibility gene for asthma and allergy, is preferentially expressed on T-helper 2 (Th2) cells and functions as a potent costimulatory molecule for T-cell activation. TIM-3 is preferentially expressed on Th1 and Tc1 cells, and generates an inhibitory signal resulting in apoptosis of Th1 and Tc1 cells. TIM-3 is also expressed on some dendritic cells and can mediate phagocytosis of apoptotic cells and cross-presentation of antigen. In contrast, TIM-4 is exclusively expressed on antigen-presenting cells, where it mediates phagocytosis of apoptotic cells and plays an important role in maintaining tolerance. TIM molecules thus provide a functional repertoire for recognition of apoptotic cells, which determines whether apoptotic cell recognition leads to immune activation or tolerance, depending on the TIM molecule engaged and the cell type on which it is expressed.

PMID: 20536563 [PubMed - indexed for MEDLINE]

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Langerhans cell histiocytosis of the parietal bone with epidural and extracranial expansion - case report and a review of the literature.

Neurol Neurochir Pol. 2010 Mar-Apr;44(2):196-203

Authors: Mosiewicz A, Rola R, Jarosz B, Trojanowska A, Trojanowski T

Langerhans cell histiocytosis is a rare neoplasm that belongs to the histiocytic and dendritic cell neoplasm group according to the 2008 WHO classification. It has been defined as neoplastic proliferation of Langerhans cells that express CD1a and S-100 proteins and have Birbeck granules on the ultrastructural examination. Clinical presentation and behaviour are heterogeneous and can range from a solitary lytic bone lesion with a favourable course to a fatal disseminated leukaemia-like form, with a wide spectrum of intermediate clinical presentations between these two extremes. Here, we present a case report of a solitary calvarial lesion in an adolescent boy along with a review of the literature. Presenting features, initial diagnostic evaluation and treatment protocol of a unifocal monosystemic calvarial location of LCH are presented.

PMID: 20496290 [PubMed - indexed for MEDLINE]

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Protective immunity against lethal anaphylactic reaction in Toxoplasma gondii-infected mice by DNA vaccination with T. gondii-derived heat shock protein 70 gene.

Parasitol Int. 2010 Jun;59(2):105-11

Authors: Kikumura A, Fang H, Mun HS, Uemura N, Makino M, Sayama Y, Norose K, Aosai F

Toxoplasma gondii-derived heat shock protein 70 (T.g.HSP70) was proven to induce lethal anaphylactic reaction in T. gondii-infected mice through platelet-activating factor (PAF)-mediated, but not classical IgE-dependent, pathway via TLR4/MyD88 signal pathway. The effector cells generating PAF and causing T.g.HSP70-induced anaphylactic reaction were CD11b(+) and CD11c(+) cells, although the reaction was enhanced by marked IFN-gamma production by CD11b(+), CD11c(+), CD4(+) and CD8(+) splenocytes. In the present study, the effects of T.g.HSP70 gene vaccine targeting peripheral dendritic cells were evaluated against T.g.HSP70-induced anaphylactic reaction in T. gondii-infected mice. C57BL/6 mice receiving T.g.HSP70 gene vaccine showed prolonged survival. Platelets of peripheral blood, which completely disappeared during the T.g.HSP70-induced anaphylactic reaction, were partially restored with the T.g.HSP70 gene vaccination. The T.g.HSP70-induced marked production of PAF and IFN-gamma from splenocytes of infected mice during the T.g.HSP70-induced anaphylactic reaction was shown to decrease after the T.g.HSP70 gene vaccination. Thus, T.g.HSP70 gene vaccine induced protective immunity against T.g.HSP70-induced PAF-mediated lethal anaphylactic reaction in T. gondii-infected mice.

PMID: 20346412 [PubMed - indexed for MEDLINE]

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TL1A produced by lamina propria macrophages induces Th1 and Th17 immune responses in cooperation with IL-23 in patients with Crohn's disease.

Inflamm Bowel Dis. 2010 Apr;16(4):568-75

Authors: Kamada N, Hisamatsu T, Honda H, Kobayashi T, Chinen H, Takayama T, Kitazume MT, Okamoto S, Koganei K, Sugita A, Kanai T, Hibi T

BACKGROUND: Tumor necrosis factor (TNF)-like protein 1A (TL1A) is a member of the TNF superfamily and contributes to the pathogenesis of Crohn's disease (CD) by stimulating T-helper (Th) 1 cells. In addition to Th1, recent studies have focused on the role of Th17 cells in the pathogenesis of CD. Here we tried to clarify the role of TL1A in Th1 and Th17 immunity in CD. METHODS: TL1A expression was assessed by quantitative reverse-transcription polymerase chain reaction (RT-PCR) in lamina propria (LP) macrophages (LP-M phi s) from normal controls (NC) and patients with CD or ulcerative colitis (UC). Purified LP CD4(+) T cells were stimulated with TL1A and/or IL-23 and interferon gamma (IFN-gamma) and interleukin (IL)-17 levels were analyzed. We also examined the effect of TL1A on naïve CD4(+) T-cell differentiation. RESULTS: We found that LP-M phi s are a major producer of TL1A. TL1A expression was markedly enhanced in LP-M phi s from CD patients compared with NC or UC patients. IL-23, in addition to TL1A, was induced in LP-M phi s by commensal bacteria stimulation. TL1A and IL-23 synergistically promoted the production of IFN-gamma and IL-17 by LP T cells, while TL1A alone did not induce cytokine production. Furthermore, TL1A promoted Th17 differentiation from naïve T cells by LP-M phi s; however, IL-23 did not show any synergistic effects on Th17 differentiation. CONCLUSIONS: TL1A expressed in LP-M phi s might play an important role in the pathogenesis of CD by inducing Th1 and Th17 immunity. IL-23 differentially regulated these functions of TL1A on memory and naïve T cells.

PMID: 19834969 [PubMed - indexed for MEDLINE]

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[Nodal marginal zone B-cell lymphoma: a clinicopathologic study of 10 cases]

Zhonghua Bing Li Xue Za Zhi. 2007 Aug;36(8):529-33

Authors: Zhang YN, Zhou XG, Zhang SH, Zheng YY, Liu WH

OBJECTIVE: To study the morphologic features, immunophenotype, differential diagnosis and prognosis of nodal marginal zone B-cell lymphoma (NMZL). METHODS: Light microscopic examination and immunohistochemical study were carried out in 10 cases of NMZL. Seven of which had follow-up information available. RESULTS: All cases presented with good performance status at the time of diagnosis. Amongst the 7 cases with follow-up information available, most (6/7) were in advanced clinical stage (stage II to III). The one-year survival rate was 67%. A vaguely nodular growth pattern was observed in most cases of NMZL (5/10). The lymphoma was composed predominantly of atypical lymphoid cells resembling centrocytes (7/10). A predominance of monocytoid B-cell (2/10) or small lymphocytic (1/10) morphology was rare. Instead, the presence of a minor component of monocytoid B cells was not uncommon (5/10). Plasmacytoid or plasmacytic cells were also frequently found (8/10). The proliferation index ranged from 5% to 50%. Follicular dendritic cells appeared atrophic in 7 cases and variably hyperplasic in 3 cases. CONCLUSIONS: Primary NMZL is rare. It has a unique growth pattern and most cases are composed predominantly of cells resembling centrocytes. Differential diagnosis includes lymphoplasmacytic lymphoma, lymph node involvement by extranodal marginal zone B-cell lymphoma and T-zone hyperplasia. The clinical stage is often high at presentation, with systemic dissemination. The prognosis of NMZL is thus relatively poor.

PMID: 17980100 [PubMed - indexed for MEDLINE]