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Sample records for cell mediated hypersensitivity

  1. HLA Associations and Clinical Implications in T-Cell Mediated Drug Hypersensitivity Reactions: An Updated Review

    PubMed Central

    Cheng, Chi-Yuan; Chen, Chi-Hua; Chen, Wei-Li; Deng, Shin-Tarng; Chung, Wen-Hung

    2014-01-01

    T-cell mediated drug hypersensitivity reactions may range from mild rash to severe fatal reactions. Among them, drug reaction with eosinophilia and systemic symptoms (DRESS) or drug-induced hypersensitivity syndrome (DIHS), Stevens-Johnson syndrome/ toxic epidermal necrolysis (SJS/TEN), are some of the most life-threatening severe cutaneous adverse reactions (SCARs). Recent advances in pharmacogenetic studies show strong genetic associations between human leukocyte antigen (HLA) alleles and susceptibility to drug hypersensitivity. This review summarizes the literature on recent progresses in pharmacogenetic studies and clinical application of pharmacogenetic screening based on associations between SCARs and specific HLA alleles to avoid serious conditions associated with drug hypersensitivity. PMID:24901010

  2. T-cell-mediated drug hypersensitivity: immune mechanisms and their clinical relevance.

    PubMed

    Yun, James; Cai, Fenfen; Lee, Frederick J; Pichler, Werner J

    2016-04-01

    T-cell-mediated drug hypersensitivity represents a significant proportion of immune mediated drug hypersensitivity reactions. In the recent years, there has been an increase in understanding the immune mechanisms behind T-cell-mediated drug hypersensitivity. According to hapten mechanism, drug specific T-cell response is stimulated by drug-protein conjugate presented on major histocompatibility complex (MHC) as it is presented as a new antigenic determinant. On the other hand, p-i concept suggests that a drug can stimulate T cells via noncovalent direct interaction with T-cell receptor and/or peptide-MHC. The drug binding site is quite variable and this leads to several different mechanisms within p-i concept. Altered peptide repertoire can be regarded as an 'atypical' subset of p-i concept since the mode of the drug binding and the binding site are essentially identical to p-i concept. However, the intracellular binding of abacavir to HLA-B(*)57:01 additionally results in alteration in peptide repertoire. Furthermore the T-cell response to altered peptide repertoire model is only shown for abacavir and HLA-B(*)57:01 and therefore it may not be generalised to other drug hypersensitivity. Danger hypothesis has been postulated to play an important role in drug hypersensitivity by providing signal 2 but its experimental data is lacking at this point in time. Furthermore, the recently described allo-immune response suggests that danger signal may be unnecessary. Finally, in view of these new understanding, the classification and the definition of type B adverse drug reaction should be revised. PMID:27141480

  3. T-cell-mediated drug hypersensitivity: immune mechanisms and their clinical relevance

    PubMed Central

    Cai, Fenfen; Lee, Frederick J; Pichler, Werner J

    2016-01-01

    T-cell-mediated drug hypersensitivity represents a significant proportion of immune mediated drug hypersensitivity reactions. In the recent years, there has been an increase in understanding the immune mechanisms behind T-cell-mediated drug hypersensitivity. According to hapten mechanism, drug specific T-cell response is stimulated by drug-protein conjugate presented on major histocompatibility complex (MHC) as it is presented as a new antigenic determinant. On the other hand, p-i concept suggests that a drug can stimulate T cells via noncovalent direct interaction with T-cell receptor and/or peptide-MHC. The drug binding site is quite variable and this leads to several different mechanisms within p-i concept. Altered peptide repertoire can be regarded as an 'atypical' subset of p-i concept since the mode of the drug binding and the binding site are essentially identical to p-i concept. However, the intracellular binding of abacavir to HLA-B*57:01 additionally results in alteration in peptide repertoire. Furthermore the T-cell response to altered peptide repertoire model is only shown for abacavir and HLA-B*57:01 and therefore it may not be generalised to other drug hypersensitivity. Danger hypothesis has been postulated to play an important role in drug hypersensitivity by providing signal 2 but its experimental data is lacking at this point in time. Furthermore, the recently described allo-immune response suggests that danger signal may be unnecessary. Finally, in view of these new understanding, the classification and the definition of type B adverse drug reaction should be revised. PMID:27141480

  4. Phospholipase C/diacylglycerol kinase-mediated signalling is required for benzothiadiazole-induced oxidative burst and hypersensitive cell death in rice suspension-cultured cells.

    PubMed

    Chen, Jie; Zhang, Weidong; Song, Fengming; Zheng, Zhong

    2007-01-01

    The involvement of phospholipase C/diacylglycerol kinase (PLC/DGK)-mediated signalling in oxidative burst and hypersensitive cell death was studied in rice suspension-cultured cells treated with benzothiadiazole (BTH) and infected by Xanthomonas oryza pv. oryza (Xoo), the causal agent of rice leaf blight disease. Treatment of rice suspension cells with BTH resulted in a significant oxidative burst, as indicated by accumulation of superoxide anion and H(2)O(2), and hypersensitive cell death, as determined by Evans blue staining. A peak in oxidative burst was detected 3-4 h after BTH treatment and hypersensitive cell death was observed 8 h after treatment. In addition, significant oxidative burst and hypersensitive cell death were detected in BTH-treated suspension cells, but not in untreated control cells, after Xoo infection. Scavengers and antioxidants of active oxygen species, e.g., superoxide dismutase, catalase, N-acetylcysteine, and flavone, reduced significantly the BTH-induced oxidative burst and hypersensitive cell death, indicating that oxidative burst is required for BTH-induced hypersensitive cell death. Expression of the PLC/DGK pathway genes, a diacylglycerol kinase gene, OsDAGK1, and a phosphoinositide-specific phospholipase C gene, OsPI-PLC1, and a defence-related EREBP transcriptional factor gene, OsBIERF3, was activated in rice cells after BTH treatment and in the BTH-treated cells after Xoo infection. Treatment of rice cells with phosphatidic acid, a phospholipid signalling molecule, resulted in the production of oxidative burst and hypersensitive cell death. However, neomycin, a PLC inhibitor, inhibited partially but not completely the production of oxidative burst, hypersensitive cell death, and expression of OsBIERF3 and OsDAGK1 induced by BTH in rice cells. These results suggest that PLC/DGK-mediated signalling plays an important role in BTH-induced oxidative burst, hypersensitive response, and activation of defence response in rice.

  5. Rds and Rih mediate hypersensitive cell death independent of gene-for-gene resistance to the oat crown rust pathogen Puccinia coronata f. sp. avenae.

    PubMed

    Yu, G X; Braun, E; Wise, R P

    2001-12-01

    The Pca crown rust resistance cluster in the diploid Avena genus confers gene-for-gene specificity to numerous isolates of Puccinia coronata f. sp. avenae. Recombination breakpoint analysis indicates that specificities conferred by the Pca cluster are controlled by at least five distinct genes, designated Pc81, Pc82, Pc83, Pc84, and Pc85. Avena plants with the appropriate genotype frequently respond to P. coronata by undergoing hypersensitive cell death at the sites of fungal infection. Autofluorescence of host cells in response to P. coronata occurs in plants that develop visible necrotic lesions but not in plants that lack this phenotype. Two newly described, non-Pc loci were shown to control hypersensitive cell death. Rds (resistance-dependent suppressor of cell death) suppresses the hypersensitive response (HR), but not the resistance, mediated by the Pc82 resistance gene. In contrast, Rih (resistance-independent hypersensitive cell death) confers HR in both resistant and susceptible plants. Linkage analysis indicates that Rds is unlinked to the Pca cluster, whereas Rih is tightly linked to it. These results indicate that multiple synchronous pathways affect the development of hypersensitive cell death and that HR is not essential for resistance to crown rust. Further characterization of these genes will clarify the relationship between plant disease resistance and localized hypersensitive cell death.

  6. IgE-mediated food hypersensitivity disorders.

    PubMed

    Gotua, M; Lomidze, N; Dolidze, N; Gotua, T

    2008-04-01

    Food allergy has become a serious health concern especially in developed countries in the past two decades. In general population approximately 4-6% of children and 1-3% of adults experience food allergy. The article reviews IgE-mediated food hypersensitivity disorders. Epidemiology, Mechanism, Clinical manifestations, Genetically modified crops (GMOs), Diagnosis, Prevention and Treatment of IgE-mediated food allergies are discussed. The investigations show that over 90% of IgE-mediated food allergies in childhood are caused by: cow's milk, hen's egg, soy, peanuts, tree nuts, wheat, fish and shellfish. Also the causes of food allergy are food additives, genetically modified crops. Risk factors for food-dependent exercise-induced anaphylaxis include asthma and previous allergic reactions to the causative food. Food allergy is one of the most common causes of systematic anaphylaxis and anaphylactoid reactions, with an annual incidence of four cases per million populations and estimated 500 deaths annually. In addition to gastrointestinal symptoms, individuals may experience urticaria, angioedema, atopic dermatitis, oral syndrome, asthma, rhinitis, conjunctivitis, hypotension, shock and cardiac arrhythmias, caused by the massive release of mediators from mast cells and basophiles. Diagnosis of food allergy is based on history, detailed dietary analysis, skin testing, measuring specific IgE in blood serum and challenge tests. Treatment and prevention includes: avoidance diet, application of auto-injectable epinephrine, H1 and H2 antihistamines, corticosteroids, antileukotrienes, prostaglandin synthetase inhibitors, cromolyn sodium, etc.

  7. Hemolysate-mediated renal vasoconstriction and hypersensitization.

    PubMed

    Burke, T J; Falk, S; Conger, J D; Voelkel, N F

    1999-01-01

    The present studies measured vessel diameter, before and after addition of hemolysate, in isolated afferent arterioles (AA) and efferent arterioles (EA) obtained from the rat kidney. Human red blood cells (RBC) were hemolyzed in distilled water and membranes were discarded after centrifugation. Hemolysate added to the bath solution caused vigorous AA and EA contraction and, after washout, hypersensitized the AA and EA to doses of angiotensin II (AII) which would normally only elicit 50% contraction (EC50). Neither the contraction nor the hypersensitization were mimicked by pure human hemoglobin. The vasoconstrictive responses in the AA and EA were accompanied by increased cytosolic-free calcium concentration. Further purification (desalting) of the hemolysate to remove substance of < or = 1000 Da (which include ATP) did not eliminate the vasoconstrictive component from the hemolysate. Finally, cultured rat aortic vascular smooth muscle cells also demonstrated a rapid increase in (Ca2+i) when exposed to hemolysate. This increase in (Ca2+i) was, in part, dependent on Ca2+ influx since it could be attenuated with diltiazem (10(-5) M). In conclusion, hemolysate contains a factor which induces contractions of the isolated rat kidney AA and EA and rapid elevations in (Ca2+i). This factor, from hemolyzed RBC, is not hemoglobin itself. PMID:10048115

  8. Anandamide Attenuates Th-17 Cell-Mediated Delayed-Type Hypersensitivity Response by Triggering IL-10 Production and Consequent microRNA Induction

    PubMed Central

    Jackson, Austin R.; Nagarkatti, Prakash; Nagarkatti, Mitzi

    2014-01-01

    Endogenous cannabinoids [endocannabinoids] are lipid signaling molecules that have been shown to modulate immune functions. However, their role in the regulation of Th17 cells has not been studied previously. In the current study, we used methylated Bovine Serum Albumin [mBSA]-induced delayed type hypersensitivity [DTH] response in C57BL/6 mice, mediated by Th17 cells, as a model to test the anti-inflammatory effects of endocannabinoids. Administration of anandamide [AEA], a member of the endocannabinoid family, into mice resulted in significant mitigation of mBSA-induced inflammation, including foot pad swelling, cell infiltration, and cell proliferation in the draining lymph nodes [LN]. AEA treatment significantly reduced IL-17 and IFN-γ production, as well as decreased RORγt expression while causing significant induction of IL-10 in the draining LNs. IL-10 was critical for the AEA-induced mitigation of DTH response inasmuch as neutralization of IL-10 reversed the effects of AEA. We next analyzed miRNA from the LN cells and found that 100 out of 609 miRNA species were differentially regulated in AEA-treated mice when compared to controls. Several of these miRNAs targeted proinflammatory mediators. Interestingly, many of these miRNA were also upregulated upon in vitro treatment of LN cells with IL-10. Together, the current study demonstrates that AEA may suppress Th-17 cell–mediated DTH response by inducing IL-10 which in turn triggers miRNA that target proinflammatory pathways. PMID:24699635

  9. The antinociception of oxytocin on colonic hypersensitivity in rats was mediated by inhibition of mast cell degranulation via Ca(2+)-NOS pathway.

    PubMed

    Gong, Liping; Li, Jing; Tang, Yan; Han, Ting; Wei, Chuanfei; Yu, Xiao; Li, Jingxin; Wang, Rong; Ma, Xuelian; Liu, Kejing; Geng, Lingyun; Liu, Shaozhuang; Yan, Bing; Liu, Chuanyong

    2016-01-01

    This study was conducted to investigate the effects of oxytocin (OT) on visceral hypersensitivity/pain and mast cell degranulation and the underlying mechanisms. We found that oxytocin receptor (OTR) was expressed in colonic mast cells in humans and rats, as well as in human mast cell line-1 (HMC-1), rat basophilic leukemia cell line (RBL-2H3) and mouse mastocytoma cell line (P815). OT decreased 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced visceral hypersensitivity, colonic mast cell degranulation and histamine release after mast cell degranulation in rats. Also, OT attenuated the compound 48/80 (C48/80)-evoked histamine release in P815 cells and inward currents, responsible for the mast cell degranulation, in HMC-1, RBL-2H3 and P815 cells. Moreover, these protective effects of OT against visceral hypersensitivity and mast cell degranulation were eliminated by coadministration of OTR antagonist atosiban or a nonselective inhibitor of nitric oxide synthase (NOS), NG-Methyl-L-arginine acetate salt (L-NMMA). Notably, OT evoked a concentration-dependent increase of intracellular Ca(2+) in HMC-1, RBL-2H3 and P815 cells, which was responsible for the activation of neuronal NOS (NOS1) and endothelial NOS (NOS3). Our findings strongly suggest that OT might exert the antinociception on colonic hypersensitivity through inhibition of mast cell degranulation via Ca(2+)-NOS pathway. PMID:27538454

  10. The antinociception of oxytocin on colonic hypersensitivity in rats was mediated by inhibition of mast cell degranulation via Ca2+-NOS pathway

    PubMed Central

    Gong, Liping; Li, Jing; Tang, Yan; Han, Ting; Wei, Chuanfei; Yu, Xiao; Li, Jingxin; Wang, Rong; Ma, Xuelian; Liu, Kejing; Geng, Lingyun; Liu, Shaozhuang; Yan, Bing; Liu, Chuanyong

    2016-01-01

    This study was conducted to investigate the effects of oxytocin (OT) on visceral hypersensitivity/pain and mast cell degranulation and the underlying mechanisms. We found that oxytocin receptor (OTR) was expressed in colonic mast cells in humans and rats, as well as in human mast cell line-1 (HMC-1), rat basophilic leukemia cell line (RBL-2H3) and mouse mastocytoma cell line (P815). OT decreased 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced visceral hypersensitivity, colonic mast cell degranulation and histamine release after mast cell degranulation in rats. Also, OT attenuated the compound 48/80 (C48/80)-evoked histamine release in P815 cells and inward currents, responsible for the mast cell degranulation, in HMC-1, RBL-2H3 and P815 cells. Moreover, these protective effects of OT against visceral hypersensitivity and mast cell degranulation were eliminated by coadministration of OTR antagonist atosiban or a nonselective inhibitor of nitric oxide synthase (NOS), NG-Methyl-L-arginine acetate salt (L-NMMA). Notably, OT evoked a concentration-dependent increase of intracellular Ca2+ in HMC-1, RBL-2H3 and P815 cells, which was responsible for the activation of neuronal NOS (NOS1) and endothelial NOS (NOS3). Our findings strongly suggest that OT might exert the antinociception on colonic hypersensitivity through inhibition of mast cell degranulation via Ca2+-NOS pathway. PMID:27538454

  11. Rpi-blb2-Mediated Hypersensitive Cell Death Caused by Phytophthora infestans AVRblb2 Requires SGT1, but not EDS1, NDR1, Salicylic Acid-, Jasmonic Acid-, or Ethylene-Mediated Signaling.

    PubMed

    Oh, Sang-Keun; Kwon, Suk-Yoon; Choi, Doil

    2014-09-01

    Potato Rpi-blb2 encodes a protein with a coiled-coil-nucleotide binding site and leucine-rich repeat (CC-NBS-LRR) motif that recognizes the Phytophthora infestans AVRblb2 effector and triggers hypersensitive cell death (HCD). To better understand the components required for Rpi-blb2-mediated HCD in plants, we used virus-induced gene silencing to repress candidate genes in Rpi-blb2-transgenic Nicotiana benthamiana plants and assayed the plants for AVRblb2 effector. Rpi-blb2 triggers HCD through NbSGT1-mediated pathways, but not NbEDS1- or NbNDR1-mediated pathways. In addition, the role of salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) in Rpi-blb2-mediated HCD were analyzed by monitoring of the responses of NbICS1-, NbCOI1-, or NbEIN2-silenced or Rpi-blb2::NahG-transgenic plants. Rpi-blb2-mediated HCD in response to AVRblb2 was not associated with SA accumulation. Thus, SA affects Rpi-blb2-mediated resistance against P. infestans, but not Rpi-blb2-mediated HCD in response to AVRblb2. Additionally, JA and ET signaling were not required for Rpi-blb2-mediated HCD in N. benthamiana. Taken together, these findings suggest that NbSGT1 is a unique positive regulator of Rpi-blb2-mediated HCD in response to AVRblb2, but EDS1, NDR1, SA, JA, and ET are not required.

  12. CD8+ T cell migration to the skin requires CD4+ help in a murine model of contact hypersensitivity.

    PubMed

    Fyhrquist, Nanna; Wolff, Henrik; Lauerma, Antti; Alenius, Harri

    2012-01-01

    The relative roles of CD4+ and CD8+ T cells in contact hypersensitivity responses have not been fully solved, and remain an important question. Using an adoptive transfer model, we investigated the role of the respective T cell subset. Magnetic bead separated CD4+ and CD8+ T cells from oxazolone sensitized C57BL/6 mice were transferred into RAG-/- mice, followed by hapten challenge and analysis of inflammatory parameters at 24 hours post exposure. The CD4+ T cell recipient mice developed partial contact hypersensitivity responses to oxazolone. CD8+ T cells caused significant amplification of the response in recipients of both CD4+ and CD8+ T cells including ear swelling, type 1 inflammatory mediators, and cell killing. Unexpectedly, CD8+ T cells were not sufficient to mediate contact hypersensitivity, although abundantly present in the lymph nodes in the CD8+ T cell reconstituted mice. There were no signs of inflammation at the site of hapten exposure, indicating impaired recruitment of CD8+ T cells in the absence of CD4+ T cells. These data show that CD4+ T cells mediate contact hypersensitivity to oxazolone, but CD8+ T cells contribute with the most potent effector mechanisms. Moreover, our results suggest that CD4+ T cell function is required for the mobilization of CD8+ effector T cells to the site of hapten exposure. The results shed new light on the relative importance of CD4+ and CD8+ T cells during the effector phase of contact hypersensitivity. PMID:22916101

  13. [Cell-mediated immunity and delayed hypersensitivity study in splenectomy patients: a comparative evaluation between IFN-gamma and skin tests].

    PubMed

    Miniello, S; Jirillo, E; Urgesi, G; D'Abbicco, D; Tomasicchio, N; Bonomo, G M

    1999-01-01

    The authors of this paper attempt to indicate a feasible, easy-to-use and inexpensive instrument for daily assessing and monitoring of splenectomized subjects to see if they are immunocompromised. Skin tests which are considered easy and inexpensive, may be useful for immunological investigation if their effectiveness is considered equal to that of more difficult and expensive methods. They have also assessed the effectiveness of ST in the study of specific cell-mediated immunity in general and also in cases of delayed hypersensibility, comparatively to serum IFN gamma dosage. The latter is produced by Th1 lymphocytes and Natural Killer cells and is considered a reasonable indicator of cell-mediated immunity and Th1-related delayed hypersensibility. The results of this study confirm that ST is effective in 100% of all splenectomized patients compared to positivity of 60% for the compromise of the immunocompetent system revealed by serum IFN gamma dosage in the same sample of patients. In addition, the fundamental role of other cytokines was confirmed. These include IL-2 which is produced by Th1 lymphocytes and whose lack of results in splenectomized patients are immunocompromised. This is revealed not only by IFN gamma dosage but also by ST. PMID:10633837

  14. PERSISTENT SUPPRESSION OF CONTACT HYPERSENSITIVITY, AND ALTERED T-CELL PARAMETERS IN F344 RATS EXPOSED PERINATALLY TO 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD)

    EPA Science Inventory

    Abstract
    The outcome of perinatal low-level TCDD exposure on the T cell-mediated contact hypersensitivity response (CHS) in adult F344 rats was investigated. Suppression of the 2,4- dinitrofluorobenzene (DNFB)-specific contact hypersensitivity reponse occurred in mature off...

  15. Transcription factor NFAT1 controls allergic contact hypersensitivity through regulation of activation induced cell death program

    PubMed Central

    Kwon, Ho-Keun; Kim, Gi-Cheon; Hwang, Ji Sun; Kim, Young; Chae, Chang-Suk; Nam, Jong Hee; Jun, Chang-Duk; Rudra, Dipayan; Surh, Charles D.; Im, Sin-Hyeog

    2016-01-01

    Allergic contact hypersensitivity (CHS) is an inflammatory skin disease mediated by allergen specific T cells. In this study, we investigated the role of transcription factor NFAT1 in the pathogenesis of contact hypersensitivity. NFAT1 knock out (KO) mice spontaneously developed CHS-like skin inflammation in old age. Healthy young NFAT1 KO mice displayed enhanced susceptibility to hapten-induced CHS. Both CD4+ and CD8+ T cells from NFAT1 KO mice displayed hyper-activated properties and produced significantly enhanced levels of inflammatory T helper 1(Th1)/Th17 type cytokines. NFAT1 KO T cells were more resistant to activation induced cell death (AICD), and regulatory T cells derived from these mice showed a partial defect in their suppressor activity. NFAT1 KO T cells displayed a reduced expression of apoptosis associated BCL-2/BH3 family members. Ectopic expression of NFAT1 restored the AICD defect in NFAT1 KO T cells and increased AICD in normal T cells. Recipient Rag2−/− mice transferred with NFAT1 KO T cells showed more severe CHS sensitivity due to a defect in activation induced hapten-reactive T cell apoptosis. Collectively, our results suggest the NFAT1 plays a pivotal role as a genetic switch in CD4+/CD8+ T cell tolerance by regulating AICD process in the T cell mediated skin inflammation. PMID:26777750

  16. Immune cell populations in cutaneous delayed-type hypersensitivity

    PubMed Central

    1983-01-01

    Delayed-type hypersensitivity (DTH) is a prototypic T lymphocyte- mediated response to antigenic challenge. In this study, mononuclear cells infiltrating the skin during cutaneous response to tuberculin in presensitized human subjects (responders) and nonimmune controls were identified using monoclonal antibodies by indirect immunofluorescence. In both responders and controls the infiltrate consisted mainly of T lymphocytes (T11+ and OKT3+) and monocytes (OKM1+, 63D3+, Mo2+) which initially accumulated in proximity to small blood vessels and later infiltrated the interstitial dermis and epidermis. More T lymphocytes reacted with OKT4 than with OKT8. 6 h after tuberculin the ratio of OKT4/OKT8 in tissue from responders exceeded that in blood, whereas in tissues studied at 15-48 h and in all control tissues those ratios in blood and tissue were similar. Evidence of T lymphocyte activation was sought using monoclonal antibodies anti-Tac, OKT9, and OKT10. In responders but not in controls the proportion of infiltrating cells reactive with these antibodies increased during the course of DTH. The presence of activated T lymphocytes in tissue was not associated with a comparable increase in peripheral blood cell populations identified by anti-Tac and OKT10. Studies using anti-B1, Leu-7, and anti-IgD/IgM revealed comparatively few reactive cells. Dual-labeling studies demonstrated that most Leu-7--reactive cells also bound T11 while fewer bound OKM1 or OKT8 and that cells reactive with OKIa1 and T11 constituted largely nonoverlapping populations. Specific patterns of reactivity were not observed when tissues were stained with anti-human C3, or poly C9-MA, a monoclonal antibody reactive with a neoantigen on polymerized C9 of the membrane attack complex of complement. The number of epidermal Langerhans cells identified by OKT6 was similar in responders and controls. Thus, the cutaneous response to tuberculin in sensitized individuals is characterized by early enrichment of

  17. In vitro Models to Evaluate Drug-Induced Hypersensitivity: Potential Test Based on Activation of Dendritic Cells

    PubMed Central

    Galbiati, Valentina; Papale, Angela; Kummer, Elena; Corsini, Emanuela

    2016-01-01

    Hypersensitivity drug reactions (HDRs) are the adverse effect of pharmaceuticals that clinically resemble allergy. HDRs account for approximately 1/6 of drug-induced adverse effects, and include immune-mediated (“allergic”) and non-immune-mediated (“pseudo allergic”) reactions. In recent years, the severe and unpredicted drug adverse events clearly indicate that the immune system can be a critical target of drugs. Enhanced prediction in preclinical safety evaluation is, therefore, crucial. Nowadays, there are no validated in vitro or in vivo methods to screen the sensitizing potential of drugs in the pre-clinical phase. The problem of non-predictability of immunologically-based hypersensitivity reactions is related to the lack of appropriate experimental models rather than to the lack of -understanding of the adverse phenomenon. We recently established experimental conditions and markers to correctly identify drug associated with in vivo hypersensitivity reactions using THP-1 cells and IL-8 production, CD86 and CD54 expression. The proposed in vitro method benefits from a rationalistic approach with the idea that allergenic drugs share with chemical allergens common mechanisms of cell activation. This assay can be easily incorporated into drug development for hazard identification of drugs, which may have the potential to cause in vivo hypersensitivity reactions. The purpose of this review is to assess the state of the art of in vitro models to assess the allergenic potential of drugs based on the activation of dendritic cells. PMID:27462271

  18. In vitro Models to Evaluate Drug-Induced Hypersensitivity: Potential Test Based on Activation of Dendritic Cells.

    PubMed

    Galbiati, Valentina; Papale, Angela; Kummer, Elena; Corsini, Emanuela

    2016-01-01

    Hypersensitivity drug reactions (HDRs) are the adverse effect of pharmaceuticals that clinically resemble allergy. HDRs account for approximately 1/6 of drug-induced adverse effects, and include immune-mediated ("allergic") and non-immune-mediated ("pseudo allergic") reactions. In recent years, the severe and unpredicted drug adverse events clearly indicate that the immune system can be a critical target of drugs. Enhanced prediction in preclinical safety evaluation is, therefore, crucial. Nowadays, there are no validated in vitro or in vivo methods to screen the sensitizing potential of drugs in the pre-clinical phase. The problem of non-predictability of immunologically-based hypersensitivity reactions is related to the lack of appropriate experimental models rather than to the lack of -understanding of the adverse phenomenon. We recently established experimental conditions and markers to correctly identify drug associated with in vivo hypersensitivity reactions using THP-1 cells and IL-8 production, CD86 and CD54 expression. The proposed in vitro method benefits from a rationalistic approach with the idea that allergenic drugs share with chemical allergens common mechanisms of cell activation. This assay can be easily incorporated into drug development for hazard identification of drugs, which may have the potential to cause in vivo hypersensitivity reactions. The purpose of this review is to assess the state of the art of in vitro models to assess the allergenic potential of drugs based on the activation of dendritic cells. PMID:27462271

  19. Langerhans cell function dictates induction of contact hypersensitivity or unresponsiveness to DNFB in Syrian hamsters

    SciTech Connect

    Streilein, J.W.; Bergstresser, P.R.

    1981-09-01

    The relationship between distribution and function of Langerhans cells within the epidermis and the capacity of cutaneous surfaces to promote the induction of contact hypersensitivity to DNFB have been examined in inbred Syrian hamsters. In a manner very similar to previous findings in mice, the results indicate that hamster cutaneous surfaces deficient in normally functioning Langerhans cells, naturally (cheek pouch epithelium) or artificially (after perturbation with ultraviolet light), are inefficient at promoting DNFB sensitization. Instead, DNFB applied to these regions of skin results in the induction of a state of specific unresponsiveness. Viable lymphoid cells from unresponsive hamsters can transfer the unresponsiveness to naive hamsters suggesting that active suppression is at least partly responsible, probably mediated by T lymphocytes.

  20. Blast cells transfer experimental hypersensitivity pneumonitis in guinea pigs

    SciTech Connect

    Schuyler, M.; Cook, C.; Listrom, M.; Fengolio-Preiser, C.

    1988-06-01

    We previously demonstrated that experimental hypersensitivity pneumonitis (HP) can be transferred by lymph node cells (LNC) cultured in vitro with antigen. The purpose of this study was to identify the cells responsible for transfer and to determine if pulmonary cells can transfer HP. We cultured LNC from sensitized Strain 2 guinea pigs with a soluble extract of Micropolyspora faeni for 72 h, separated lymphoblasts from small lymphocytes, and transferred both subpopulations intravenously to syngeneic recipients. We also transferred irradiated lymphoblasts (1,500 rads), macrophage-depleted, lymphoblast-enriched populations, and pulmonary cells either without culture or after culture with M. faeni. Control animals received an equal volume of medium. All recipient animals were challenged intratracheally (i.t.) with M. faeni 48 h after the cell transfer, and they were killed 4 days after i.t. challenge. Randomly selected microscopic fields of the lung (250/animal) were judged to be normal or abnormal without knowledge of treatment. This measurement was reproducible (r = 0.95 for duplicate measurements, n = 55). All guinea pigs were maintained in HEPA-filtered air. There was a low level of pulmonary response to an i.t. challenge of M. faeni in animals that received medium. Animals that received pulmonary cells, either cultured or noncultured, did not differ from those in the control group. There was a substantial increase (p less than 0.01) in the extent of pulmonary abnormalities in the recipients of the lymphoblast population, with significant correlation (r = 0.87, p less than 0.01) between the number of lymphoblasts transferred and the extent of pulmonary abnormalities.

  1. Hapten-Induced Contact Hypersensitivity, Autoimmune Reactions, and Tumor Regression: Plausibility of Mediating Antitumor Immunity

    PubMed Central

    Erkes, Dan A.; Selvan, Senthamil R.

    2014-01-01

    Haptens are small molecule irritants that bind to proteins and elicit an immune response. Haptens have been commonly used to study allergic contact dermatitis (ACD) using animal contact hypersensitivity (CHS) models. However, extensive research into contact hypersensitivity has offered a confusing and intriguing mechanism of allergic reactions occurring in the skin. The abilities of haptens to induce such reactions have been frequently utilized to study the mechanisms of inflammatory bowel disease (IBD) to induce autoimmune-like responses such as autoimmune hemolytic anemia and to elicit viral wart and tumor regression. Hapten-induced tumor regression has been studied since the mid-1900s and relies on four major concepts: (1) ex vivo haptenation, (2) in situ haptenation, (3) epifocal hapten application, and (4) antigen-hapten conjugate injection. Each of these approaches elicits unique responses in mice and humans. The present review attempts to provide a critical appraisal of the hapten-mediated tumor treatments and offers insights for future development of the field. PMID:24949488

  2. Ten weeks of infection with a tissue-invasive helminth protects against local immune complex-mediated inflammation, but not cutaneous type I hypersensitivity, in previously sensitized mice

    PubMed Central

    Evans, Holly; Killoran, Kristin E.; Mitre, Blima K.; Morris, C. Paul; Kim, So-Young; Mitre, Edward

    2015-01-01

    In this study we evaluated the effect chronic helminth infection has on allergic disease in mice previously sensitized to ovalbumin (OVA). 10 weeks of infection with Litomosoides sigmodontis reduced immunological markers of type I hypersensitivity, including OVA-specific IgE, basophil activation, and mast cell degranulation. Despite these reductions, there was no protection against immediate clinical hypersensitivity following intradermal OVA challenge. However, late phase ear swelling, due to type III hypersensitivity, was significantly reduced in chronically infected animals. Levels of total IgG2a, OVA-specific IgG2a, and OVA-specific IgG1 were reduced in the setting of infection. These reductions were likely due to increased antibody catabolism as ELISPOT assays demonstrated that infected animals do not have suppressed antibody production. Ear histology 24 hours after challenge showed infected animals have reduced cellular infiltration in the ear, with significant decreases in numbers of neutrophils and macrophages. Consistent with this, infected animals had less neutrophil-specific chemokines CXCL-1 and CXCL-2 in the ear following challenge. Additionally, in vitro stimulation with immune-complexes resulted in significantly less CXCL-1 and CXCL-2 production by eosinophils from chronically infected mice. Expression of FcγRI was also significantly reduced on eosinophils from infected animals. These data indicate that chronic filarial infection suppresses eosinophilic responses to antibody-mediated activation and has the potential to be used as a therapeutic for pre-existing hypersensitivity diseases. PMID:26324775

  3. Characterization of Candida albicans mannan-induced, mannan-specific delayed hypersensitivity suppressor cells.

    PubMed

    Garner, R E; Childress, A M; Human, L G; Domer, J E

    1990-08-01

    We have shown previously that CBA/J mice immunized with Candida albicans developed delayed hypersensitivity (DH) demonstrable with mannan (MAN) extracted from the same organism and that the intravenous (i.v.) injection of MAN prior to or during the immunization phase resulted in the suppression of the MAN-specific DH response. In this study, we demonstrate that MAN-induced suppression of DH is a T-lymphocyte-mediated phenomenon. Suppressor cells induced in vivo by the i.v. injection of MAN into naive mice 1 to 7 days prior to harvest were passaged through nylon wool, treated with various surface-specific antibodies and complement, and then injected i.v. into immunized syngeneic recipients. Enrichment of splenic T cells by passage over nylon wool and transfer of the nylon-wool-nonadherent populations to immunized recipient mice suppressed DH in a dose-dependent manner. Depletion of Thy+ or Lyt-2+ cells from nylon-wool-nonadherent populations regularly ablated the ability of such suspensions to transfer suppression. Treatment of the same transfer suspensions with anti-Lyt-1 had variable effects, suggesting that the surface density of the Lyt-1 antigen was not as constant from population to population as was the Lyt-2 antigen. In addition, C. albicans MAN-induced suppressor cells were able to suppress DH demonstrable with Candida tropicalis MAN in animals immunized with C. tropicalis. Suppression of DH by MAN in this model, therefore, is mediated by Thy+ Lyt-2+ lymphocytes.

  4. IgE-Mediated Hypersensitivity and Desensitisation with Recombinant Enzymes in Pompe Disease and Type I and Type VI Mucopolysaccharidosis.

    PubMed

    Capanoglu, Murat; Dibek Misirlioglu, Emine; Azkur, Dilek; Vezir, Emine; Guvenir, Hakan; Gunduz, Mehmet; Toyran, Muge; Civelek, Ersoy; Kocabas, Can Naci

    2016-01-01

    Enzyme replacement therapy (ERT) is important for the treatment of lysosomal storage disorders. Hypersensitivity reactions with ERT have been reported, and in these cases, desensitisation with the enzyme is necessary. Here we report the cases of 3 patients with lysosomal storage disorders, including Pompe disease and mucopolysaccharidosis type I and VI, who had IgE-mediated hypersensitivity reactions and positive skin tests. Successful desensitisation protocols with the culprit enzyme solution were used for these patients. All 3 patients were able to safely receive ERT with the desensitisation protocol. PMID:27144408

  5. DNase I hypersensitive sites flank the mouse class II major histocompatibility complex during B cell development.

    PubMed Central

    Carson, S

    1991-01-01

    The mouse class II major histocompatibility complex (MHC) encodes a polymorphic, multigene family important in the immune response, and is expressed mainly on mature B cells, on certain types of dendritic cells and is also inducible by gamma-interferon on antigen presenting cells. To study the regulatory elements which control this expression pattern, we have examined the chromatin structure flanking the class II MHC region, in particular during B cell differentiation. Using a panel of well-characterised mouse cell lines specific for different stages of B cell development (pre-B, B, plasma cell) as well as non-B cell lines, we have mapped the DNase I hypersensitive (DHS) sites adjacent to the mouse MHC class II region. The results presented show, for the first time that there are specific hypersensitive sites flanking the class II MHC locus during pre B cell, B cell and plasma cell stages of B cell differentiation, irrespective of the status of class II MHC expression. These hypersensitive sites are not found in T cell, fibroblast or uninduced myelomonocytic cell lines. This suggests that these DHS sites define a developmentally stable, chromatin structure, which can be used as a marker of B cell lineage commitment and may indicate that a combination of these hypersensitive sites reflect regulatory proteins involved in the immediate expression of a particular class II MHC gene or possibly control of the entire locus. Images PMID:1923768

  6. Delayed-type hypersensitivity response in experimental autoimmune neuritis treated with peptide-coupled spleen cells.

    PubMed

    Gregorian, S K; Rostami, A

    1994-04-01

    Experimental autoimmune neuritis (EAN) is a T cell-mediated autoimmune inflammatory disease of the peripheral nervous system that is characterized by demyelination and mononuclear cell infiltration. It is induced in Lewis rats by administration of myelin P2 protein or a synthetic peptide (SP-26) corresponding to amino acid residues 53-78 of bovine P2 protein. Recently, we showed that SP-26, when coupled to syngeneic spleen cells and administered intravenously, provided an effective means of inducing tolerance by inhibiting the clinical signs, decreased proliferative response of lymphoid cells to SP-26 and histological changes of EAN. However, our current data indicate that, despite tolerance induction in these Lewis rats, the antigen-specific delayed-type hypersensitivity (DTH) response to SP-26 remained intact. Furthermore, interferon (IFN)-gamma production by spleen cells of tolerized rats were unchanged as compared to EAN rats. The in vitro proliferation of T lymphocytes from tolerized rats stimulated by SP-26 was reduced as compared to EAN controls but was enhanced upon addition of exogenous interleukin-2. Thus, reduction in EAN clinical signs does not necessarily indicate a decrease in DTH response and IFN-gamma production in EAN Lewis rats. The implication of this finding in regard to immunoregulatory mechanism of DTH response is discussed. PMID:7512578

  7. Delayed-type hypersensitivity response in experimental autoimmune neuritis treated with peptide-coupled spleen cells.

    PubMed

    Gregorian, S K; Rostami, A

    1994-04-01

    Experimental autoimmune neuritis (EAN) is a T cell-mediated autoimmune inflammatory disease of the peripheral nervous system that is characterized by demyelination and mononuclear cell infiltration. It is induced in Lewis rats by administration of myelin P2 protein or a synthetic peptide (SP-26) corresponding to amino acid residues 53-78 of bovine P2 protein. Recently, we showed that SP-26, when coupled to syngeneic spleen cells and administered intravenously, provided an effective means of inducing tolerance by inhibiting the clinical signs, decreased proliferative response of lymphoid cells to SP-26 and histological changes of EAN. However, our current data indicate that, despite tolerance induction in these Lewis rats, the antigen-specific delayed-type hypersensitivity (DTH) response to SP-26 remained intact. Furthermore, interferon (IFN)-gamma production by spleen cells of tolerized rats were unchanged as compared to EAN rats. The in vitro proliferation of T lymphocytes from tolerized rats stimulated by SP-26 was reduced as compared to EAN controls but was enhanced upon addition of exogenous interleukin-2. Thus, reduction in EAN clinical signs does not necessarily indicate a decrease in DTH response and IFN-gamma production in EAN Lewis rats. The implication of this finding in regard to immunoregulatory mechanism of DTH response is discussed.

  8. Trans-Epithelial Immune Cell Transfer during Suckling Modulates Delayed-Type Hypersensitivity in Recipients as a Function of Gender

    PubMed Central

    Ma, Lisa J.; Walter, Barbara; DeGuzman, Ariel; Muller, H. Konrad; Walker, Ameae M.

    2008-01-01

    Introduction Breast feeding has long term effects on the developing immune system which outlive passive immunization of the neonate. We have investigated the transfer of milk immune cells and examined the result of transfer once the recipients were adult. Methods Non-transgenic mouse pups were foster-nursed by green fluorescent protein (GFP) transgenic dams for 3 weeks and the fate of GFP+ cells was followed by FACS analysis, immunohistochemistry and RT-PCR for GFP and appropriate immune cell markers. Pups suckled by non-transgenic dams served as controls. Results Despite a preponderance of B cells and macrophages in the stomach contents of the pups, most cells undergoing trans-epithelial migration derived from the 3–4% of milk cells positive for T lymphocyte markers. These cells homed to the spleen and thymus, with maximal accumulation at 3–4 weeks. By sensitizing dams with an antigen which elicits a T cell-mediated delayed-type-hypersensitivity (DTH) response, we determined that nursing by a sensitized dam (compared to a non-sensitized dam) amplified a subsequent DTH response in females and yet suppressed one in males. Discussion These results suggest that clinical evaluation weighing the pros and cons of nursing male versus female children by mothers with genetically-linked hypersensitivity diseases, such as celiac disease and eczema, or those in regions of the world with endemic DTH-eliciting diseases, such as tuberculosis, may be warranted. PMID:18958163

  9. Role of mast cell in the late phase of contact hypersensitivity induced by trimellitic anhydride

    PubMed Central

    Chai, Ok Hee

    2015-01-01

    Mast cells are known as effector cells of IgE-mediated allergic responses, but role of mast cells in contact hypersensitivity (CHS) has been considered controversial. In this study, we investigated role of mast cell in trimellitic anhydride (TMA)-induced CHS. The mice were sensitized to TMA on the back and repeatedly challenged with TMA on the left ear at 1-week intervals. The ear after challenge showed biphasic responses. The repetition of TMA challenge shifted in time course of ear response and enlarged the extent of early and late phase reactions in proportion to the frequency of TMA challenges in C57BL/6 mice. In late phase reaction, peak of ear response by single challenge showed at 24 hours after challenge, but the peak by repeat challenges at 8 hours after the last challenge. Number of mast cells and eosinophils per unit area increased in proportion to frequency of TMA challenges. However, mast cell-deficient WBB6F1/J-KitW/KitW-v mice developed the late phase reaction without the early phase reaction. The repetition of TMA challenge shifted in time course of ear response and enlarged the extent of ear response and the infiltration of eosinophils. The magnitude of these responses observed according to the frequency of the TMA challenge in mast cell-deficient WBB6F1/J-KitW/KitW-v mice was significantly lower than that in C57BL/6 mice. Also TMA elicited mast cell degranulation and histamine release from rat peritoneal mast cells in a concentration-dependent manner. Conclusively, TMA induces the early and late phase reactions in CHS, and mast cells may be required for TMA-induced CHS. PMID:26770872

  10. Virus-induced gene silencing reveals signal transduction components required for the Pvr9-mediated hypersensitive response in Nicotiana benthamiana.

    PubMed

    Tran, Phu-Tri; Choi, Hoseong; Choi, Doil; Kim, Kook-Hyung

    2016-08-01

    Resistance to pathogens mediated by plant resistance (R) proteins requires different signaling transduction components and pathways. Our previous studies revealed that a potyvirus resistance gene in pepper, Pvr9, confers a hypersensitive response (HR) to pepper mottle virus in Nicotiana benthamiana. Our results show that the Pvr9-mediated HR against pepper mottle virus infection requires HSP90, SGT1, NDR1, but not EDS1. These results suggest that the Pvr9-mediated HR is possibly related to the SA pathway but not the ET, JA, ROS or NO pathways.

  11. Drug hypersensitivity reactions involving skin.

    PubMed

    Hausmann, Oliver; Schnyder, Benno; Pichler, Werner J

    2010-01-01

    Immune reactions to drugs can cause a variety of diseases involving the skin, liver, kidney, lungs, and other organs. Beside immediate, IgE-mediated reactions of varying degrees (urticaria to anaphylactic shock), many drug hypersensitivity reactions appear delayed, namely hours to days after starting drug treatment, showing a variety of clinical manifestations from solely skin involvement to fulminant systemic diseases which may be fatal. Immunohistochemical and functional studies of drug-specific T cells in patients with delayed reactions confirmed a predominant role for T cells in the onset and maintenance of immune-mediated delayed drug hypersensitivity reactions (type IV reactions). In these reactions, drug-specific CD4+ and CD8+ T cells are stimulated by drugs through their T cell receptors (TCR). Drugs can stimulate T cells in two ways: they can act as haptens and bind covalently to larger protein structures (hapten-carrier model), inducing a specific immune response. In addition, they may accidentally bind in a labile, noncovalent way to a particular TCR of the whole TCR repertoire and possibly also major histocompatibility complex (MHC)-molecules - similar to their pharmacologic action. This seems to be sufficient to reactivate certain, probably in vivo preactivated T cells, if an additional interaction of the drug-stimulated TCR with MHC molecules occurs. The mechanism was named pharmacological interaction of a drug with (immune) receptor and thus termed the p-i concept. This new concept may explain the frequent skin symptoms in drug hypersensitivity to oral or parenteral drugs. Furthermore, the various clinical manifestations of T cell-mediated drug hypersensitivity may be explained by distinct T cell functions leading to different clinical phenotypes. These data allowed a subclassification of the delayed hypersensitivity reactions (type IV) into T cell reactions which, by releasing certain cytokines and chemokines, preferentially activate and recruit

  12. In vitro evidence of delayed-type hypersensitivity to hydrocortisone.

    PubMed

    Wilkinson, S M; English, J S; Mattey, D L

    1993-11-01

    Hypersensitivity to topical hydrocortisone is becoming increasingly recognized. We present further evidence that this is mediated via a delayed-type hypersensitivity reaction. A hydrocortisone: albumin complex was able to induce a proliferative response in the peripheral blood mononuclear cells of patients allergic to hydrocortisone. Protein binding of hydrocortisone or a degradation product may be important in the development of corticosteroid allergy.

  13. Clinical food hypersensitivity: the relevance of duodenal immunoglobulin E-positive cells.

    PubMed

    Caffarelli, C; Romanini, E; Caruana, P; Street, M E; de' Angelis, G

    1998-10-01

    Owing to poor reliability of laboratory tests, diagnosis of food allergy is based on clinical response to double-blind placebo-controlled food challenge. The aim of the present study was to assess the value of duodenal IgE-positive cells in the diagnosis of food allergy. Thirty-one children with a history of possible food allergy underwent duodenal biopsies, skin prick tests, and measurement of serum IgE antibodies, and were put on an elimination diet followed by food challenge. Open food challenges were performed in patients under 12 mo of age, and double-blind placebo-controlled challenges were for suspected foods. On the basis of clinical food hypersensitivity, patients were divided into two groups. Group 1 consisted of 13 children with food allergy. Thirteen of 20 positive provocations elicited reactions within 12 h from the end of the challenge, seven later. Group 2 was the control group and included 18 patients with negative food challenges. The number of IgE-positive cells in biopsy specimens was significantly more elevated in group 1 with respect to group 2 (153.24 +/- 83.13 versus 18.4 +/- 18.9; p < 0.01). Total serum IgE levels were elevated compared with that of the control group (p < 0.01) and correlated with the number of IgE-positive cells (p < 0.001, r = 0.62). Enhanced IgE-containing cells were found in all delayed reactors, but about one-third had negative skin prick tests or specific serum IgE antibodies to the offending foods. Our results showed that systemic reactions to foods are associated with an IgE-mediated response in the duodenal mucosa. Larger studies would be required to assess the predictive value of an increased number of IgE-positive cells in the diagnosis of allergy to food, especially in children with delayed reactions.

  14. Role of the potassium chloride cotransporter isoform 2-mediated spinal chloride homeostasis in a rat model of visceral hypersensitivity.

    PubMed

    Tang, Dong; Qian, Ai-Hua; Song, Dan-Dan; Ben, Qi-Wen; Yao, Wei-Yan; Sun, Jing; Li, Wei-Guang; Xu, Tian-Le; Yuan, Yao-Zong

    2015-05-01

    Visceral hypersensitivity represents an important hallmark in the pathophysiology of irritable bowel syndrome (IBS), of which the mechanisms remain elusive. The present study was designed to examine whether cation-chloride cotransporter (CCC)-mediated chloride (Cl(-)) homeostasis of the spinal cord is involved in chronic stress-induced visceral hypersensitivity. Chronic visceral hypersensitivity was induced by exposing male Wistar rats to water avoidance stress (WAS). RT-PCR, Western blotting, and immunohistochemistry were used to assess the expression of CCCs in the spinal cord. Patch-clamp recordings were performed on adult spinal cord slices to evaluate Cl(-) homeostasis and Cl(-) extrusion capacity of lamina I neurons. Visceral sensitivity was estimated by measuring the abdominal withdrawal reflex in response to colorectal distension (CRD). After 10 days of WAS exposure, levels of both total protein and the oligomeric form of the K(+)-Cl(-) cotransporter isoform 2 (KCC2), but not Na(+)-K(+)-2Cl(-) transporter isoform 1 (NKCC1), were significantly decreased in the dorsal horn of the lumbosacral spinal cord. The downregulation of KCC2 resulted in a depolarizing shifted equilibrium potential of GABAergic inhibitory postsynaptic current and impaired Cl(-) extrusion capacity in lamina I neurons of the lumbosacral spinal cord from WAS rats. Acute noxious CRD disrupted spinal KCC2 expression and function 2 h after the final distention in sham rats, but not in WAS rats. Pharmacological blockade of KCC2 activity by intrathecal injection of a KCC2 inhibitor [(dihydroindenyl)oxy] alkanoic acid enhanced visceral nociceptive sensitivity in sham rats, but not in WAS rats. These results suggest that KCC2 downregulation-mediated impairment of spinal cord Cl(-) homeostasis may play an important role in chronic stress-induced visceral hypersensitivity. PMID:25792562

  15. Lymphoid tissue phospholipase A2 group IID resolves contact hypersensitivity by driving antiinflammatory lipid mediators

    PubMed Central

    Miki, Yoshimi; Yamamoto, Kei; Taketomi, Yoshitaka; Sato, Hiroyasu; Shimo, Kanako; Kobayashi, Tetsuyuki; Ishikawa, Yukio; Ishii, Toshiharu; Nakanishi, Hiroki; Ikeda, Kazutaka; Taguchi, Ryo; Kabashima, Kenji; Arita, Makoto; Arai, Hiroyuki; Lambeau, Gérard; Bollinger, James M.; Hara, Shuntaro; Gelb, Michael H.

    2013-01-01

    Resolution of inflammation is an active process that is mediated in part by antiinflammatory lipid mediators. Although phospholipase A2 (PLA2) enzymes have been implicated in the promotion of inflammation through mobilizing lipid mediators, the molecular entity of PLA2 subtypes acting upstream of antiinflammatory lipid mediators remains unknown. Herein, we show that secreted PLA2 group IID (PLA2G2D) is preferentially expressed in CD11c+ dendritic cells (DCs) and macrophages and displays a pro-resolving function. In hapten-induced contact dermatitis, resolution, not propagation, of inflammation was compromised in skin and LNs of PLA2G2D-deficient mice (Pla2g2d−/−), in which the immune balance was shifted toward a proinflammatory state over an antiinflammatory state. Bone marrow-derived DCs from Pla2g2d−/− mice were hyperactivated and elicited skin inflammation after intravenous transfer into mice. Lipidomics analysis revealed that PLA2G2D in the LNs contributed to mobilization of a pool of polyunsaturated fatty acids that could serve as precursors for antiinflammatory/pro-resolving lipid mediators such as resolvin D1 and 15-deoxy-Δ12,14-prostaglandin J2, which reduced Th1 cytokine production and surface MHC class II expression in LN cells or DCs. Altogether, our results highlight PLA2G2D as a “resolving sPLA2” that ameliorates inflammation through mobilizing pro-resolving lipid mediators and points to a potential use of this enzyme for treatment of inflammatory disorders. PMID:23690440

  16. Hypersensitivities for acetaldehyde and other agents among cancer cells null for clinically relevant Fanconi anemia genes.

    PubMed

    Ghosh, Soma; Sur, Surojit; Yerram, Sashidhar R; Rago, Carlo; Bhunia, Anil K; Hossain, M Zulfiquer; Paun, Bogdan C; Ren, Yunzhao R; Iacobuzio-Donahue, Christine A; Azad, Nilofer A; Kern, Scott E

    2014-01-01

    Large-magnitude numerical distinctions (>10-fold) among drug responses of genetically contrasting cancers were crucial for guiding the development of some targeted therapies. Similar strategies brought epidemiological clues and prevention goals for genetic diseases. Such numerical guides, however, were incomplete or low magnitude for Fanconi anemia pathway (FANC) gene mutations relevant to cancer in FANC-mutation carriers (heterozygotes). We generated a four-gene FANC-null cancer panel, including the engineering of new PALB2/FANCN-null cancer cells by homologous recombination. A characteristic matching of FANCC-null, FANCG-null, BRCA2/FANCD1-null, and PALB2/FANCN-null phenotypes was confirmed by uniform tumor regression on single-dose cross-linker therapy in mice and by shared chemical hypersensitivities to various inter-strand cross-linking agents and γ-radiation in vitro. Some compounds, however, had contrasting magnitudes of sensitivity; a strikingly high (19- to 22-fold) hypersensitivity was seen among PALB2-null and BRCA2-null cells for the ethanol metabolite, acetaldehyde, associated with widespread chromosomal breakage at a concentration not producing breaks in parental cells. Because FANC-defective cancer cells can share or differ in their chemical sensitivities, patterns of selective hypersensitivity hold implications for the evolutionary understanding of this pathway. Clinical decisions for cancer-relevant prevention and management of FANC-mutation carriers could be modified by expanded studies of high-magnitude sensitivities.

  17. Estrogen deprivation causes estradiol hypersensitivity in human breast cancer cells.

    PubMed

    Masamura, S; Santner, S J; Heitjan, D F; Santen, R J

    1995-10-01

    Genetic and environmental factors can modulate the level of sensitivity to various hormones, including estrogens. Enhanced sensitivity to estradiol (E2) has been demonstrated in several biological conditions, such as in sheep during the nonbreeding season, in untreated patients with Turner's syndrome, and in the prepubertal state in normal girls. We postulated that secondary responses to hormonal therapy in patients with breast cancer could also result from enhanced E2 sensitivity, developing as an adaptive mechanism to E2 deprivation. The present study used the MCF-7 human breast cancer cell line as a model system to test the concept that enhanced sensitivity to E2 may occur as a result of adaptation to low E2 levels. After depriving MCF-7 cells of estrogens in tissue culture medium for periods of 1-6 months, we established conditions under which replication could be stimulated maximally by 10(-14)-10(-15) mol/L E2. In contrast, wild-type cells not exposed to estrogen deprivation required 10(-10) mol/L E2 to grow at the same rate. Further, the concentration of the antiestrogen, ICI 164384, needed to inhibit growth by 50% in estrogen-deprived cells was much lower than that required in wild-type cells (i.e. 10(-15) vs. 10(-9) mol/L). Nude mice implanted with these estrogen-deprived cells demonstrated an earlier appearance of palpable tumors in response to E2 than animals bearing wild-type cells. Reexposure to 10(-10)-10(-9) mol/L E2, either in vivo or in vitro, returned these cells to the level of estrogen sensitivity observed in wild-type cells. Taken together, these observations suggest that breast cancer cells can adapt to low levels of estrogens by enhancing their sensitivity to E2.

  18. Azuki bean cells are hypersensitive to cadmium and do not synthesize phytochelatins.

    PubMed

    Inouhe, M; Ito, R; Ito, S; Sasada, N; Tohoyama, H; Joho, M

    2000-07-01

    Suspension-cultured cells of azuki bean (Vigna angularis) as well as the original root tissues were hypersensitive to Cd (<10 microM). Repeated subculturings with a sublethal level of Cd (1-10 microM) did not affect the subsequent response of cells to inhibitory levels of Cd (10-100 microM). The azuki bean cells challenged to Cd did not contain phytochelatin (PC) peptides, unlike tomato (Lycopersicon esculentum) cells that have a substantial tolerance to Cd (>100 microM). Both of the cell suspensions contained a similar level of reduced glutathione (GSH) when grown in the absence of Cd. Externally applied GSH to azuki bean cells recovered neither Cd tolerance nor PC synthesis of the cells. Furthermore, enzyme assays in vitro revealed that the protein extracts of azuki bean cells had no activity converting GSH to PCs, unlike tomato. These results suggest that azuki bean cells are lacking in the PC synthase activity per se, hence being Cd hypersensitive. We concluded that the PC synthase has an important role in Cd tolerance of suspension-cultured cells. PMID:10889252

  19. The Phytoalexin Resveratrol Regulates the Initiation of Hypersensitive Cell Death in Vitis Cell

    PubMed Central

    Chang, Xiaoli; Heene, Ernst; Qiao, Fei; Nick, Peter

    2011-01-01

    Resveratrol is a major phytoalexin produced by plants in response to various stresses and promotes disease resistance. The resistance of North American grapevine Vitis rupestris is correlated with a hypersensitive reaction (HR), while susceptible European Vitis vinifera cv. ‘Pinot Noir’ does not exhibit HR, but expresses basal defence. We have shown previously that in cell lines derived from the two Vitis species, the bacterial effector Harpin induced a rapid and sensitive accumulation of stilbene synthase (StSy) transcripts, followed by massive cell death in V. rupestris. In the present work, we analysed the function of the phytoalexin resveratrol, the product of StSy. We found that cv. ‘Pinot Noir’ accumulated low resveratrol and its glycoside trans-piceid, whereas V. rupestris produced massive trans-resveratrol and the toxic oxidative δ-viniferin, indicating that the preferred metabolitism of resveratrol plays role in Vitis resistance. Cellular responses to resveratrol included rapid alkalinisation, accumulation of pathogenesis-related protein 5 (PR5) transcripts, oxidative burst, actin bundling, and cell death. Microtubule disruption and induction of StSy were triggered by Harpin, but not by resveratrol. Whereas most responses proceeded with different amplitude for the two cell lines, the accumulation of resveratrol, and the competence for resveratrol-induced oxidative burst differed in quality. The data lead to a model, where resveratrol, in addition to its classical role as antimicrobial phytoalexin, represents an important regulator for initiation of HR-related cell death. PMID:22053190

  20. Cutting Edge: Redox Signaling Hypersensitivity Distinguishes Human Germinal Center B Cells.

    PubMed

    Polikowsky, Hannah G; Wogsland, Cara E; Diggins, Kirsten E; Huse, Kanutte; Irish, Jonathan M

    2015-08-15

    Differences in the quality of BCR signaling control key steps of B cell maturation and differentiation. Endogenously produced H2O2 is thought to fine tune the level of BCR signaling by reversibly inhibiting phosphatases. However, relatively little is known about how B cells at different stages sense and respond to such redox cues. In this study, we used phospho-specific flow cytometry and high-dimensional mass cytometry (CyTOF) to compare BCR signaling responses in mature human tonsillar B cells undergoing germinal center (GC) reactions. GC B cells, in contrast to mature naive B cells, memory B cells, and plasmablasts, were hypersensitive to a range of H2O2 concentrations and responded by phosphorylating SYK and other membrane-proximal BCR effectors in the absence of BCR engagement. These findings reveal that stage-specific redox responses distinguish human GC B cells.

  1. Cell-mediated immunity in anorexia nervosa.

    PubMed Central

    Cason, J; Ainley, C C; Wolstencroft, R A; Norton, K R; Thompson, R P

    1986-01-01

    Twelve patients with anorexia nervosa were studied for cell-mediated immunity in terms of delayed hypersensitivity reactions to recall antigens, lymphocyte transformation responses to T-cell mitogens, and numbers of circulating leucocytes and T-cell subpopulations. Compared to controls, all patients had reduced cutaneous reactions and four were anergic. There was a mild leucopenia in patients and both T4+ and T3+ numbers were slightly reduced. Mean peak transformation responses for patients were slightly lower than controls for phytohaemagglutinin, but not for concanavalin A; however, patients required greater doses of mitogens to elicit peak transformation responses. Plasmas from patients did not contain inhibitors of transformation responses. We conclude that there are functional cellular abnormalities associated with the under-nutrition of anorexia nervosa. PMID:3742879

  2. Transplant-mediated enhancement of spinal cord GABAergic inhibition reverses paclitaxel-induced mechanical and heat hypersensitivity.

    PubMed

    Bráz, João M; Wang, Xidao; Guan, Zhonghui; Rubenstein, John L; Basbaum, Allan I

    2015-06-01

    Decreased spinal cord GABAergic inhibition is a major contributor to the persistent neuropathic pain that can follow peripheral nerve injury. Recently, we reported that restoring spinal cord GABAergic signaling by intraspinal transplantation of cortical precursors of GABAergic interneurons from the embryonic medial ganglionic eminence (MGE) can reverse the mechanical hypersensitivity (allodynia) that characterizes a neuropathic pain model in the mouse. We show that MGE cell transplants are also effective against both the mechanical allodynia and the heat hyperalgesia produced in a paclitaxel-induced chemotherapy model of neuropathic pain. To test the necessity of GABA release by the transplants, we also studied the utility of transplanting MGE cells from mice with a deletion of VGAT, the vesicular GABA transporter. Transplants from these mice, in which GABA is synthesized but cannot be stored or released, had no effect on mechanical hypersensitivity or heat hyperalgesia in the paclitaxel model. Taken together, these results demonstrate the therapeutic potential of GABAergic precursor cell transplantation in diverse neuropathic pain models and support our contention that restoration of inhibitory controls through release of GABA from the transplants is their mode of action. PMID:25760475

  3. The role of cell-mediated immunity in typhoid.

    PubMed

    Mabel, T J; Paniker, C K

    1979-06-01

    The cell-mediated immunity in typhoid was assessed by the leukocyte migration inhibition test and delayed hypersensitivity skin test in 60 clinical typhoid patients. The property of leukocyte migration inhibition appeared first and was positive in 28 of 60 (46.7%) patients on admission and 45 of 60 (75%) at the time of discharge. This difference was definitely more in blood culture positive patients. The delayed hypersensitivity appeared later and was positive in 18 of 60 (30%) on admission and 31 of 60 (51.7%) at the time of discharge. Patients with positive cellular-immune response against typhoid antigen did not develop relapse. On the whole cell-mediated immunity seems to play an important role in typoid. The control groups--the medical and surgical patients, doctors, clinical students and preclinical students--showed positive cellular immune response of 43.3 81.3, 40.7 and 25% respectively. The significance of these results is discussed.

  4. The immune response to infection with vaccinia virus in mice. II. Appearance of hypersensitivity, production of macrophage migration inhibitory factor and transformation of spleen cells in response to virus antigens.

    PubMed Central

    Hutt, L. M.

    1975-01-01

    The appearance of specific hypersensitivity to virus antigens was examined in mice infected intravenously with vaccinia virus. Both immediate hypersensitivity, transferable by serum, and delayed-type hypersensitivity, transferable only by cells, were apparent 8 days after infection and demonstrable for at least a further 130 days. Production of macrophage migration inhibitory factor by lymphocytes from infected mice was measured directly in terms of inhibition of migration by antigen or indirectly by determining the effect of soluble factors elaborated by the stimulated lymphocytes. The irregular results may have been the resultants of antigen-mediated macrophage stimulation, toxicity and induction of migration inhibitory factor. Transformation of spleen cells - presumably lymphocytes - from infected mice could be induced in vitro by virus antigens for at least 139 days after infection. Virus/lymphocyte interaction appears to be a particularly fruitful area for further study. PMID:1056960

  5. Genotyping for Severe Drug Hypersensitivity

    PubMed Central

    Karlin, Eric; Phillips, Elizabeth

    2014-01-01

    Over the past decade, there have been significant advances in our understanding of the immunopathogenesis and pharmacogenomics of severe immunologically-mediated adverse drug reactions. Such T-cell-mediated adverse drug reactions such as Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN), drug-induced liver disease (DILI) and other drug hypersensitivity syndromes have more recently been shown to be mediated through interactions with various class I and II HLA alleles. Key examples have included the associations of HLA-B*15:02 and carbamazepine induced SJS/TEN in Southeast Asian populations and HLA-B*57:01 and abacavir hypersensitivity. HLA-B*57:01 screening to prevent abacavir hypersensitivity exemplifies a successful translational roadmap from pharmacogenomic discovery through to widespread clinical implementation. Ultimately, our increased understanding of the interaction between drugs and the MHC could be used to inform drug design and drive pre-clinical toxicity programs to improve drug safety. PMID:24429903

  6. Chapter 28: Classification of hypersensitivity reactions.

    PubMed

    Uzzaman, Ashraf; Cho, Seong H

    2012-01-01

    The original Gell and Coomb's classification categorizes hypersensitivity reactions into four subtypes according to the type of immune response and the effector mechanism responsible for cell and tissue injury: type I, immediate or IgE mediated; type II, cytotoxic or IgG/IgM mediated; type III, IgG/IgM immune complex mediated; and type IV, delayed-type hypersensitivity or T-cell mediated. The classification has been improved so that type IIa is the former type II and type IIb is antibody-mediated cell stimulating (Graves Disease and the "autoimmune" type of chronic idiopathic urticaria). Type IV has four major categories: type IVa is CD4(+)Th1 lymphocyte mediated with activation of macrophages (granuloma formation and type I diabetes mellitus); type IVb is CD4(+)Th2 lymphocyte mediated with eosinophilic involvement (persistent asthma and allergic rhinitis); type IVc is cytotoxic CD8(+) T lymphocyte with involvement of perforin-granzme B in apoptosis (Stevens-Johnson syndrome and toxic epidermal necrolysis); type IVd is T-lymphocyte-driven neutrophilic inflammation (pustular psoriasis and acute generalized exanthematous pustulosis). Some diseases have multiple types of immunologic hypersensitivity.

  7. Use of lymphoblastoid cell lines to evaluate the hypersensitivity to ultraviolet radiation in Cockayne syndrome

    SciTech Connect

    Otsuka, F.; Tarone, R.E.; Cayeux, S.; Robbins, J.H.

    1984-05-01

    Cockayne syndrome (CS) is a rare autosomal recessive disease characterized by acute sun sensitivity, cachectic dwarfism, and neurologic and skeletal abnormalities. Cultured skin fibroblasts from patients with this disease are known to be hypersensitive to the lethal effects of 254-nm UV radiation. The authors have studied the sensitivity of 254-nm UV radiation of lymphoblastoid lines derived from 3 typical CS patients, 1 atypical CS patient who had a very late age of onset of clinical manifestations, 2 patients who had both xeroderma pigmentosum (XP) and typical CS, and 3 heterozygous parents of these patients. Post-UV survival was determined by the trypan-blue dye-exclusion method. The lymphoblastoid lines from the 3 typical CS patients, the atypical CS patient, and the 2 patients with both CS and XP had decreased post-UV viability in comparison with lines from normal donors. Lines from the heterozygous parents had normal post-UV viability. The post-UV viability of the typical CS lines was similar to that of a XP complementation group C line. The relative post-UV viability of lymphoblastoid lines from the typical CS patients was similar to the relative post-UV survival of their fibroblast lines. The lymphoblastoid line from the atypical CS patient had a post-UV viability similar to that of the typical CS patients. Thus, the relative hypersensitivity of CS patients cells in vitro does not reflect the severity or age of onset of the patients clinical manifestations. The lymphoblastoid lines from the 2 patients who had both CS and XP were significantly more sensitive to the UV radiation than those from patients with only CS. Our studies demonstrate that lymphoblastoid lines from patients with CS are appropriate and useful cell lines for the study of the inherited hypersensitivity to UV radiation.

  8. In Vivo Expansion of Endogenous Regulatory T Cell Populations Induces Long-Term Suppression of Contact Hypersensitivity.

    PubMed

    El Beidaq, Asmaa; Link, Christopher W M; Hofmann, Katharina; Frehse, Britta; Hartmann, Karin; Bieber, Katja; Martin, Stefan F; Ludwig, Ralf J; Manz, Rudolf A

    2016-09-01

    Contact hypersensitivity (CHS) of murine skin serves as a model of allergic contact dermatitis. Hapten-specific CD8 T cells and neutrophils represent the major effector cells driving this inflammatory reaction whereas Foxp3(+) regulatory T cells (Tregs) control the severity of inflammation. However, whether in vivo expansion of endogenous Tregs can downregulate CHS-mediated inflammation remains to be elucidated. In this study, we addressed this issue by using injection of an IL-2/anti-IL-2 mAb JES6-1 complex (IL-2/JES6-1) as a means of Treg induction in 2,4,6-trinitrochlorobenzene-induced CHS. IL-2/JES6-1 injection before or after hapten sensitization led to a considerable reduction of skin inflammation, even when rechallenged up to 3 wk after the last treatment. Conversely, Treg depletion re-established the CHS response in IL-2/JES6-1-treated mice. IL-2/JES6-1 injection resulted in increased frequencies of natural and peripheral Tregs in spleen and draining lymph nodes (LNs), elevated IL-10 and TGF-β production by CD4 T cells, reduced CD86 expression by dendritic cells, and led to lower numbers of hapten-specific IFN-γ-producing CD8 T effector cells in LNs. Neutrophil and CD8 T cell infiltration was reduced in inflamed ear tissue, whereas CTLA-4(+)Foxp3(+) Treg frequencies were augmented. Adoptive transfer of LN cells of sensitized mice into recipients treated with IL-2/JES6-1 showed impaired CHS. Our results show that in vivo Treg expansion results in a prolonged CHS suppression, a sustained reduction of hapten-specific CD8 T cells, and a decrease in effector cell influx in inflamed tissue. PMID:27439515

  9. NADPH Oxidase-Derived ROS Induced by Chronic Intermittent Hypoxia Mediates Hypersensitivity of Lung Vagal C Fibers in Rats.

    PubMed

    Yang, Chang-Huan; Zhuang, Wei-Ling; Shen, Yan-Jhih; Lai, Ching Jung; Kou, Yu Ru

    2016-01-01

    Obstructive sleep apnea (OSA), manifested by exposure to chronic intermittent hypoxia (CIH) and excess production of reactive oxygen species (ROS) in the airways, is associated with hyperreactive airway diseases. ROS, particularly when created by NADPH oxidase, are known to sensitize lung vagal C fibers (LVCFs), which may contribute to airway hypersensitivity pathogenesis. We investigated whether CIH augments the reflex and afferent responses of LVCFs to chemical stimulants and the roles of ROS and NADPH oxidase in such airway hypersensitivity. Rats were exposed to room air (RA) or CIH with/without daily treatment with MnTMPyP (a superoxide anion scavenger), apocynin (an NADPH oxidase inhibitor), or vehicle. At 16 h after their last exposure, intravenous capsaicin, adenosine, or α,β-methylene-ATP evoked an augmented apneic response in anesthetized rats with 14-days CIH exposure, compared to anesthetized rats with 14-days RA exposure. The augmented apneic responses to these LVCF stimulants were abolished by bilateral vagotomy or perivagal capsaicin treatment, which block LVCFs neural conduction and were significantly suppressed by treatment with MnTMPyP or apocynin, but not vehicle. Electrophysiological studies revealed that 14-days CIH exposure potentiated the responses of LVCFs to these stimulants. This effect was inhibited by treatment with MnTMPyP or apocynin treatment and was not seen in rats who received 7-days of CIH exposure. Biochemical analysis indicated that 14-days CIH exposure increased both lung lipid peroxidation, which is indicative of oxidative stress, and expression of the p47(phox) subunit in the membrane fraction of lung tissue, which is an index of NADPH oxidase activation. The former was prevented by treatment with either MnTMPyP or apocynin, while the later was prevented by treatment with apocynin only. These results suggest that 14-days CIH exposure sensitizes LVCFs in rats, leading to an exaggerated reflex and afferent responses to

  10. NADPH Oxidase-Derived ROS Induced by Chronic Intermittent Hypoxia Mediates Hypersensitivity of Lung Vagal C Fibers in Rats

    PubMed Central

    Yang, Chang-Huan; Zhuang, Wei-Ling; Shen, Yan-Jhih; Lai, Ching Jung; Kou, Yu Ru

    2016-01-01

    Obstructive sleep apnea (OSA), manifested by exposure to chronic intermittent hypoxia (CIH) and excess production of reactive oxygen species (ROS) in the airways, is associated with hyperreactive airway diseases. ROS, particularly when created by NADPH oxidase, are known to sensitize lung vagal C fibers (LVCFs), which may contribute to airway hypersensitivity pathogenesis. We investigated whether CIH augments the reflex and afferent responses of LVCFs to chemical stimulants and the roles of ROS and NADPH oxidase in such airway hypersensitivity. Rats were exposed to room air (RA) or CIH with/without daily treatment with MnTMPyP (a superoxide anion scavenger), apocynin (an NADPH oxidase inhibitor), or vehicle. At 16 h after their last exposure, intravenous capsaicin, adenosine, or α,β-methylene-ATP evoked an augmented apneic response in anesthetized rats with 14-days CIH exposure, compared to anesthetized rats with 14-days RA exposure. The augmented apneic responses to these LVCF stimulants were abolished by bilateral vagotomy or perivagal capsaicin treatment, which block LVCFs neural conduction and were significantly suppressed by treatment with MnTMPyP or apocynin, but not vehicle. Electrophysiological studies revealed that 14-days CIH exposure potentiated the responses of LVCFs to these stimulants. This effect was inhibited by treatment with MnTMPyP or apocynin treatment and was not seen in rats who received 7-days of CIH exposure. Biochemical analysis indicated that 14-days CIH exposure increased both lung lipid peroxidation, which is indicative of oxidative stress, and expression of the p47phox subunit in the membrane fraction of lung tissue, which is an index of NADPH oxidase activation. The former was prevented by treatment with either MnTMPyP or apocynin, while the later was prevented by treatment with apocynin only. These results suggest that 14-days CIH exposure sensitizes LVCFs in rats, leading to an exaggerated reflex and afferent responses to

  11. Involvement of the outer wall layer of Cladosporium cladosporioides in an IgG-mediated hypersensitivity.

    PubMed

    Bergen, M S; Yang, T J; Collins, R P

    1988-01-01

    The serum of an individual hypersensitive to the fungus Cladosporium cladosporioides reacted with the outer wall layer of germinating spores, immature hyphae, and, to a lesser extent, mature mycelium, as detected by the indirect immunofluorescence assay when goat anti-human IgG, but not goat anti-human IgE, was employed. The outer wall layer of ungerminated spores, however, did not react with the patient's serum and the anti-human IgG probe. When ungerminated spores were vortexed in physiological saline for 1 min, approximately 8 pg of protein/spore was released; this rapid release of protein may have been the cause of the loss of antigenic activity from the outer wall layer of ungerminated spores during the immunoassay process. Immunoblotting revealed the presence of a high molecular weight antigen in all the extracts of the fungus at various stages of the life cycle, including ungerminated and germinating spores, hyphae in the logarithmic phase, mature mycelium, and a culture filtrate of C. cladosporioides.

  12. Inflammatory pain hypersensitivity mediated by phenotypic switch in myelinated primary sensory neurons

    NASA Astrophysics Data System (ADS)

    Neumann, Simona; Doubell, Tim P.; Leslie, Tabi; Woolf, Clifford J.

    1996-11-01

    PAIN is normally evoked only by stimuli that are sufficiently intense to activate high-threshold Aδ and C sensory fibres, which relay the signal to the spinal cord. Peripheral inflammation leads to profoundly increased pain sensitivity: noxious stimuli generate a greater response and stimuli that are normally innocuous elicit pain. Inflammation increases the sensitivity of the peripheral terminals of Aδ and C fibres at the site of inflammation1. It also increases the excitability of spinal cord neurons2,3, which now amplify all sensory inputs including the normally innocuous tactile stimuli that are conveyed by low-threshold Aβ fibres. This central sensitization has been attributed to the enhanced activity of C fibres4, which increase the excitability of their postsynaptic targets by releasing glutamate and the neuropeptide substance P5-7. Here we show that inflammation results in Aβ fibres also acquiring the capacity to increase the excitability of spinal cord neurons. This is due to a phenotypic switch in a subpopulation of these fibres so that they, like C-fibres, now express substance P. Aβ fibres thus appear to contribute to inflammatory hypersensitivity by switching their phenotype to one resembling pain fibres, thereby enhancing synaptic transmission in the spinal cord and exaggerating the central response to innocuous stimuli.

  13. Regulation of delayed-type hypersensitivity. III. Effect of cyclophosphamide on the suppressor cells for delayed-type hypersensitivity to sheep erythrocytes in mice.

    PubMed

    Gill, H K; Liew, F Y

    1978-03-01

    A previous study (Eur. J. Immunol. 1977. 7: 714) has shown that mice injected intravenously (i.v.) with 4 x10(9) sheep red blood cells (SRBC) produce cells which suppress delayed-type hypersensitivity (DTH). These suppressor cells are theta-positive, antigen-specific and act via a soluble factor which does not bear immunoglobulin determinants (Eur. J. Immunol. 1978. 8: 168). The present paper demonstrates that these suppressor cells are inhibitable by cyclophosphamide (CY). Mice injected with graded amounts of CY two days prior to SRBC injection, showed maximum augmentation of DTH at 200 mg/kg body weight, a dose which completely suppressed the appearance of splenic plaque-forming cells (PFC) to SRBC. In contrast, lower doses of CY enhanced both DTH and PFC responses. Time course studies showed that CY inhibited the precursors of suppressor cells and had little or no effect on suppressor cells which have already encountered antigens. This was further confirmed by passive transfer studies which showed tha- suppressor cells were inhibited if CY was administered at the same time or 2 days before SRBC injection, but were not affected if CY was given after antigen stimulation. Direct evidence for the effect of CY on suppressor cells was obtained by cell fractination with a Ficoll density gradient. The denser suppressor cell population was absent from the spleens of mice treated with 200 mg/kg of CY 2 days before i.v. injection with 1 x 10(9) SRBC.

  14. A novel IL-10-producing innate lymphoid cells (ILC10) in a contact hypersensitivity mouse model

    PubMed Central

    Kim, Hyuk Soon; Jang, Jong-Hwa; Lee, Min Bum; Jung, In Duk; Park, Yeong-Min; Kim, Young Mi; Choi, Wahn Soo

    2016-01-01

    The immunoregulatory cytokine Interleukin 10 (IL-10) protein is produced by various cells during the course of inflammatory disorders. Mainly, it downregulates pro-inflammatory cytokines, antigen presentation, and helper T cell activation. In this study, we show that the ratio of IL-10-producing cells was significantly increased in lineage negative (i.e., not T, B, or leukocyte cell lineages) cells than in lineage positive cells in lymphoid and peripheral tissues. We further observed that IL-10-producing innate lymphoid cells (ILCs), here called firstly ILC10, were increased in number in oxazolone-induced contact hypersensitivity (CHS) mice. In detail, IL-10-producing lineage negative cells were elevated in the axillary, inguinal lymph node, and ear tissues of CHS mice. Notably, the cells expressed classical ILC marker proteins such as CD45, CD127, and Sca-1. Altogether, our findings suggest for the first time that ILC10s are present in various physiological settings and could be involved in numerous immune responses as regulatory cells. [BMB Reports 2016; 49(5): 293-296] PMID:26949018

  15. Early transplantation of mesenchymal stem cells after spinal cord injury relieves pain hypersensitivity through suppression of pain-related signaling cascades and reduced inflammatory cell recruitment.

    PubMed

    Watanabe, Shuji; Uchida, Kenzo; Nakajima, Hideaki; Matsuo, Hideaki; Sugita, Daisuke; Yoshida, Ai; Honjoh, Kazuya; Johnson, William E B; Baba, Hisatoshi

    2015-06-01

    Bone marrow-derived mesenchymal stem cells (BMSC) modulate inflammatory/immune responses and promote motor functional recovery after spinal cord injury (SCI). However, the effects of BMSC transplantation on central neuropathic pain and neuronal hyperexcitability after SCI remain elusive. This is of importance because BMSC-based therapies have been proposed for clinical treatment. We investigated the effects of BMSC transplantation on pain hypersensitivity in green fluorescent protein (GFP)-positive bone marrow-chimeric mice subjected to a contusion SCI, and the mechanisms of such effects. BMSC transplantation at day 3 post-SCI improved motor function and relieved SCI-induced hypersensitivities to mechanical and thermal stimulation. The pain improvements were mediated by suppression of protein kinase C-γ and phosphocyclic AMP response element binding protein expression in dorsal horn neurons. BMSC transplants significantly reduced levels of p-p38 mitogen-activated protein kinase and extracellular signal-regulated kinase (p-ERK1/2) in both hematogenous macrophages and resident microglia and significantly reduced the infiltration of CD11b and GFP double-positive hematogenous macrophages without decreasing the CD11b-positive and GFP-negative activated spinal-microglia population. BMSC transplants prevented hematogenous macrophages recruitment by restoration of the blood-spinal cord barrier (BSCB), which was associated with decreased levels of (a) inflammatory cytokines (tumor necrosis factor-α, interleukin-6); (b) mediators of early secondary vascular pathogenesis (matrix metallopeptidase 9); (c) macrophage recruiting factors (CCL2, CCL5, and CXCL10), but increased levels of a microglial stimulating factor (granulocyte-macrophage colony-stimulating factor). These findings support the use of BMSC transplants for SCI treatment. Furthermore, they suggest that BMSC reduce neuropathic pain through a variety of related mechanisms that include neuronal sparing and

  16. Cancer Cells with Alternative Lengthening of Telomeres Do Not Display a General Hypersensitivity to ATR Inhibition

    PubMed Central

    Deeg, Katharina I.; Chung, Inn; Bauer, Caroline; Rippe, Karsten

    2016-01-01

    Telomere maintenance is a hallmark of cancer as it provides cancer cells with cellular immortality. A significant fraction of tumors uses the alternative lengthening of telomeres (ALT) pathway to elongate their telomeres and to gain an unlimited proliferation potential. Since the ALT pathway is unique to cancer cells, it represents a potentially valuable, currently unexploited target for anti-cancer therapies. Recently, it was proposed that ALT renders cells hypersensitive to ataxia telangiectasia- and RAD3-related (ATR) protein inhibitors (Flynn et al., Science 347, 273). Here, we measured the response of various ALT- or telomerase-positive cell lines to the ATR inhibitor VE-821. In addition, we compared the effect of the inhibitor on cell viability in isogenic cell lines, in which ALT was active or suppressed. In these experiments, a general ATR inhibitor sensitivity of cells with ALT could not be confirmed. We rather propose that the observed variations in sensitivity reflect differences between cell lines that are unrelated to ALT.

  17. Cancer Cells with Alternative Lengthening of Telomeres Do Not Display a General Hypersensitivity to ATR Inhibition.

    PubMed

    Deeg, Katharina I; Chung, Inn; Bauer, Caroline; Rippe, Karsten

    2016-01-01

    Telomere maintenance is a hallmark of cancer as it provides cancer cells with cellular immortality. A significant fraction of tumors uses the alternative lengthening of telomeres (ALT) pathway to elongate their telomeres and to gain an unlimited proliferation potential. Since the ALT pathway is unique to cancer cells, it represents a potentially valuable, currently unexploited target for anti-cancer therapies. Recently, it was proposed that ALT renders cells hypersensitive to ataxia telangiectasia- and RAD3-related (ATR) protein inhibitors (Flynn et al., Science 347, 273). Here, we measured the response of various ALT- or telomerase-positive cell lines to the ATR inhibitor VE-821. In addition, we compared the effect of the inhibitor on cell viability in isogenic cell lines, in which ALT was active or suppressed. In these experiments, a general ATR inhibitor sensitivity of cells with ALT could not be confirmed. We rather propose that the observed variations in sensitivity reflect differences between cell lines that are unrelated to ALT. PMID:27602331

  18. BHK cell lines with increased rates of gene amplification are hypersensitive to ultraviolet light

    SciTech Connect

    Giulotto, E.; Bertoni, L.; Attolini, C.; Rainaldi, G.; Anglana, M. )

    1991-04-15

    Four cell lines (MP1, -4, -5, -7), isolated from baby hamster kidney cells after simultaneous selection with N-(phosphonacetyl)-L-aspartate and methotrexate, have previously been shown to amplify their DNA at an increased rate. We now show that all four lines are hypersensitive to killing by UV light and mitomycin C. At high doses of UV light or mitomycin C, the MP lines survived less than 10% or less than 5% as well as parental cells, respectively. After UV irradiation, inhibition of DNA and RNA synthesis was greater in MP than in parental cells, and recovery was slower or absent. A 2- to 3.5-fold increase in the frequency of UV-induced sister chromatid exchange was also seen in the four cell lines. In MP5, unscheduled DNA replication after treatment with UV light was only approximately 70% as great as in parental cells and the other MP lines. In MP4 and MP7 cells S phase was elongated. Although their individual properties confirm that the four cell lines are independent, their common properties suggest a relationship between tolerance of DNA damage and gene amplification.

  19. Cancer Cells with Alternative Lengthening of Telomeres Do Not Display a General Hypersensitivity to ATR Inhibition

    PubMed Central

    Deeg, Katharina I.; Chung, Inn; Bauer, Caroline; Rippe, Karsten

    2016-01-01

    Telomere maintenance is a hallmark of cancer as it provides cancer cells with cellular immortality. A significant fraction of tumors uses the alternative lengthening of telomeres (ALT) pathway to elongate their telomeres and to gain an unlimited proliferation potential. Since the ALT pathway is unique to cancer cells, it represents a potentially valuable, currently unexploited target for anti-cancer therapies. Recently, it was proposed that ALT renders cells hypersensitive to ataxia telangiectasia- and RAD3-related (ATR) protein inhibitors (Flynn et al., Science 347, 273). Here, we measured the response of various ALT- or telomerase-positive cell lines to the ATR inhibitor VE-821. In addition, we compared the effect of the inhibitor on cell viability in isogenic cell lines, in which ALT was active or suppressed. In these experiments, a general ATR inhibitor sensitivity of cells with ALT could not be confirmed. We rather propose that the observed variations in sensitivity reflect differences between cell lines that are unrelated to ALT. PMID:27602331

  20. Modulation of visceral hypersensitivity by glial cell line-derived neurotrophic factor family receptor α-3 in colorectal afferents

    PubMed Central

    Shinoda, M.; Feng, B.; Albers, K. M.; Gebhart, G. F.

    2011-01-01

    Irritable bowel syndrome is characterized by colorectal hypersensitivity and contributed to by sensitized mechanosensitive primary afferents and recruitment of mechanoinsensitive (silent) afferents. Neurotrophic factors are well known to orchestrate dynamic changes in the properties of sensory neurons. Although pain modulation by proteins in the glial cell line-derived neurotrophic factor (GDNF) family has been documented in various pathophysiological states, their role in colorectal hypersensitivity remains unexplored. Therefore, we investigated the involvement of the GDNF family receptor α-3 (GFRα3) signaling in visceral hypersensitivity by quantifying visceromotor responses (VMR) to colorectal distension before and after intracolonic treatment with 2,4,6-trinitrobenzene sulfonic acid (TNBS). Baseline responses to colorectal distension did not differ between C57BL/6 and GFRα3 knockout (KO) mice. Relative to intracolonic saline treatment, TNBS significantly enhanced the VMR to colorectal distension in C57BL/6 mice 2, 7, 10, and 14 days posttreatment, whereas TNBS-induced visceral hypersensitivity was significantly suppressed in GFRα3 KO mice. The proportion of GFRα3 immunopositive thoracolumbar and lumbosacral colorectal dorsal root ganglion neurons was significantly elevated 2 days after TNBS treatment. In single fiber recordings, responses to circumferential stretch of colorectal afferent endings in C57BL/6 mice were significantly increased (sensitized) after exposure to an inflammatory soup, whereas responses to stretch did not sensitize in GFRα3 KO mice. These findings suggest that enhanced GFRα3 signaling in visceral afferents may contribute to development of colorectal hypersensitivity. PMID:21193524

  1. Genome-wide detection of DNase I hypersensitive sites in single cells and FFPE tissue samples.

    PubMed

    Jin, Wenfei; Tang, Qingsong; Wan, Mimi; Cui, Kairong; Zhang, Yi; Ren, Gang; Ni, Bing; Sklar, Jeffrey; Przytycka, Teresa M; Childs, Richard; Levens, David; Zhao, Keji

    2015-12-01

    DNase I hypersensitive sites (DHSs) provide important information on the presence of transcriptional regulatory elements and the state of chromatin in mammalian cells. Conventional DNase sequencing (DNase-seq) for genome-wide DHSs profiling is limited by the requirement of millions of cells. Here we report an ultrasensitive strategy, called single-cell DNase sequencing (scDNase-seq) for detection of genome-wide DHSs in single cells. We show that DHS patterns at the single-cell level are highly reproducible among individual cells. Among different single cells, highly expressed gene promoters and enhancers associated with multiple active histone modifications display constitutive DHS whereas chromatin regions with fewer histone modifications exhibit high variation of DHS. Furthermore, the single-cell DHSs predict enhancers that regulate cell-specific gene expression programs and the cell-to-cell variations of DHS are predictive of gene expression. Finally, we apply scDNase-seq to pools of tumour cells and pools of normal cells, dissected from formalin-fixed paraffin-embedded tissue slides from patients with thyroid cancer, and detect thousands of tumour-specific DHSs. Many of these DHSs are associated with promoters and enhancers critically involved in cancer development. Analysis of the DHS sequences uncovers one mutation (chr18: 52417839G>C) in the tumour cells of a patient with follicular thyroid carcinoma, which affects the binding of the tumour suppressor protein p53 and correlates with decreased expression of its target gene TXNL1. In conclusion, scDNase-seq can reliably detect DHSs in single cells, greatly extending the range of applications of DHS analysis both for basic and for translational research, and may provide critical information for personalized medicine. PMID:26605532

  2. IREN, a novel EF-hand motif-containing nuclease, functions in the degradation of nuclear DNA during the hypersensitive response cell death in rice.

    PubMed

    Ootsubo, Yuka; Hibino, Takanori; Wakazono, Takahito; Mukai, Yukio; Che, Fang-Sik

    2016-01-01

    The hypersensitive response (HR), a type of programmed cell death that is accompanied by DNA degradation and loss of plasma membrane integrity, is a common feature of plant immune responses. We previously reported that transcription of IREN which encodes a novel EF-hand containing plant nuclease is controlled by OsNAC4, a key positive regulator of HR cell death. Transient overexpression of IREN in rice protoplasts also led to rapid DNA fragmentation, while suppression of IREN using RNA interference showed remarkable decrease of DNA fragmentation during HR cell death. Maximum DNA degradation associated with the recombinant IREN was observed in the presence of Ca(2+) and Mg(2+) or Ca(2+) and Mn(2+). Interestingly, DNA degradation mediated by the recombinant IREN was completely abolished by Zn(2+), even when Ca(2+), Mg(2+), or Mn(2+) were present in the reaction buffer. These data indicate that IREN functions in the degradation of nuclear DNA during HR cell death.

  3. Genome-wide Detection of DNase I Hypersensitive Sites in Single Cells and FFPE Samples

    PubMed Central

    Jin, Wenfei; Tang, Qingsong; Wan, Mimi; Cui, Kairong; Zhang, Yi; Ren, Gang; Ni, Bing; Sklar, Jeffrey; Przytycka, Teresa M.; Childs, Richard; Levens, David; Zhao, Keji

    2015-01-01

    DNase I hypersensitive sites (DHSs) provide important information on the presence of transcriptional regulatory elements and the state of chromatin in mammalian cells1–3. Conventional DNase-Seq for genome-wide DHSs profiling is limited by the requirement of millions of cells4,5. Here we report an ultrasensitive strategy, called Pico-Seq, for detection of genome-wide DHSs in single cells. We show that DHS patterns at the single cell level are highly reproducible among individual cells. Among different single cells, highly expressed gene promoters and the enhancers associated with multiple active histone modifications display constitutive DHS while chromatin regions with fewer histone modifications exhibit high variation of DHS. Furthermore, the single-cell DHSs predict enhancers that regulate cell-specific gene expression programs and the cell-to-cell variations of DHS are predictive of gene expression. Finally, we apply Pico-Seq to pools of tumor cells and pools of normal cells, dissected from formalin-fixed paraffin-embedded (FFPE) tissue slides from thyroid cancer patients, and detect thousands of tumor-specific DHSs. Many of these DHSs are associated with promoters and enhancers critically involved in cancer development. Analysis of the DHS sequences uncovers one single-nucleotide variant (chr18:52417839 G>C) in the tumor cells of a follicular thyroid carcinoma patient, which affects the binding of the tumor suppressor protein p53 and correlates with decreased expression of its target gene TXNL1. In conclusion, Pico-Seq can reliably detect DHSs in single cells, greatly extending the range of applications of DHS analysis for both basic and translational research and may provide critical information for personalized medicine. PMID:26605532

  4. Spinal transient receptor potential ankyrin 1 channel induces mechanical hypersensitivity, increases cutaneous blood flow, and mediates the pronociceptive action of dynorphin A.

    PubMed

    Wei, H; Saarnilehto, M; Falck, L; Viisanen, H; Lasierra, M; Koivisto, A; Pertovaara, A

    2013-06-01

    We characterized pain behavior and cutaneous blood flow response induced by activation of the spinal transient receptor potential ankyrin 1 (TRPA1) channel using intrathecal drug administrations in the rat. Additionally, we assessed whether the pronociceptive actions induced by intrathecally administered dynorphin A, cholecystokinin or prostaglandin F(2α) are mediated by the spinal TRPA1 channel. Cinnamaldehyde, a TRPA1 agonist, produced a dose-related (3-10 μg) cutaneous blood flow increase and mechanical hypersensitivity effect. These effects at the currently used doses were of short duration and attenuated, although not completely, by pretreatment with A-967079, a TRPA1 antagonist. The cinnamaldehyde-induced hypersensitivity was also reduced by pretreatment with minocycline (an inhibitor of microglial activation), but not by carbenoxolone (a gap junction decoupler). In vitro study, however, indicated that minocycline only poorly blocks the TRPA1 channel. The mechanical hypersensitivity effect induced by dynorphin A, but not that by cholecystokinin or prostaglandin F(2α), was attenuated by a TRPA1 antagonist Chembridge-5861528 as well as A-967079. The cinnamaldehyde-induced cutaneous blood flow increase was not suppressed by MK-801, an NMDA receptor antagonist, or bicuculline, a GABA(A) receptor antagonist. The results indicate that spinal TRPA1 channels promote mechanical pain hypersensitivity and due to antidromic activation of nociceptive nerve fibers increase cutaneous blood flow. The attenuation of the cinnamaldehyde-induced hypersensitivity effect by minocycline may be explained by action other than block of the TRPA1 channel. Moreover, the spinal TRPA1 channel is involved in mediating the pronociceptive action of dynorphin A, but not that of the spinal cholecystokinin or prostaglandin F(2α).

  5. Diacylglycerol kinase zeta deficiency in a non-CD4+T cell compartment leads to increased peanut hypersensitivity

    PubMed Central

    Kulis, Mike; Wan, Chi-Keung; Gorentla, Balachandra K.; Burks, A. Wesley; Zhong, Xiao-Ping

    2011-01-01

    Summary Peanut sensitization in diacylglycerol kinase zeta (DGKζ) deficient mice led to elevated peanut-IgE levels and severe anaphylaxis. DGKζ deficient CD4+T cells did not account for the phenotype. Future studies will determine which immune lineage caused increased food hypersensitivity. PMID:21439625

  6. Mast Cell-Derived Tumor Necrosis Factor Can Promote Nerve Fiber Elongation in the Skin during Contact Hypersensitivity in Mice

    PubMed Central

    Kakurai, Maki; Monteforte, Rossella; Suto, Hajime; Tsai, Mindy; Nakae, Susumu; Galli, Stephen J.

    2006-01-01

    In humans, lesions of contact eczema or atopic dermatitis can exhibit increases in epidermal nerves, but the mechanism resulting in such nerve elongation are not fully understood. We found that contact hypersensitivity reactions to oxazolone in mice were associated with significant increases in the length of nerves in the epidermis and dermis. Using genetically mast cell-deficient c-kit mutant mice selectively repaired of their dermal mast cell deficiency with either wild-type or tumor necrosis factor (TNF)-deficient mast cells, we found that mast cells, and mast cell-derived TNF, significantly contributed to the elongation of epidermal and dermal PGP 9.5+ nerves and dermal CGRP+ nerves, as well as to the inflammation observed at sites of contact hypersensitivity in response to oxazolone. Moreover, the percentage of mast cells in close proximity to dermal PGP 9.5+ nerve fibers was significantly higher in wild-type mice and in c-kit mutant mice repaired of their dermal mast cell deficiency by the adoptive transfer of wild-type mast cells than in TNF-deficient mice or in TNF−/− mast cell-engrafted c-kit mutant mice. These observations show that mast cells, and mast cell-derived TNF, can promote the elongation of cutaneous nerve fibers during contact hypersensitivity in the mouse. PMID:17071594

  7. Involvement of calcitonin gene-related peptide and CCL2 production in CD40-mediated behavioral hypersensitivity in a model of neuropathic pain

    PubMed Central

    MALON, JENNIFER T.; MADDULA, SWATHI; BELL, HARMONY; CAO, LING

    2014-01-01

    The neuropeptide calcitonin gene-related peptide (CGRP) is known to play a pro-nociceptive role after peripheral nerve injury upon its release from primary afferent neurons in preclinical models of neuropathic pain. We previously demonstrated a critical role for spinal cord microglial CD40 in the development of spinal nerve L5 transection (L5Tx)-induced mechanical hypersensitivity. Herein, we investigated whether CGRP is involved in the CD40-mediated behavioral hypersensitivity. First, L5Tx was found to significantly induce CGRP expression in wild-type (WT) mice up to 14 days post-L5Tx. This increase in CGRP expression was reduced in CD40 knockout (KO) mice at day 14 post-L5Tx. Intrathecal injection of the CGRP antagonist CGRP8–37 significantly blocked L5Tx-induced mechanical hypersensitivity. In vitro, CGRP induced glial IL-6 and CCL2 production, and CD40 stimulation added to the effects of CGRP in neonatal glia. Further, there was decreased CCL2 production in CD40 KO mice compared to WT mice 21 days post-L5Tx. However, CGRP8–37 did not significantly affect spinal cord CCL2 production following L5Tx in WT mice. Altogether, these data suggest that CD40 contributes to the maintenance of behavioral hypersensitivity following peripheral nerve injury in part through two distinct pathways, the enhancement of CGRP expression and spinal cord CCL2 production. PMID:22377050

  8. Oral allergy syndrome (OAS): symptoms of IgE-mediated hypersensitivity to foods.

    PubMed

    Amlot, P L; Kemeny, D M; Zachary, C; Parkes, P; Lessof, M H

    1987-01-01

    Eighty highly atopic patients were selected for study because they had either atopic eczema (fifty cases) or atopic reactivity to foods, as judged by a positive skin-prick test (thirty cases). In all, sixty-five out of eighty subjects (81%) described symptoms of some kind provoked by foods, but correspondingly positive skin tests were found in only half of these, thirty-three out of eighty (41%). The symptoms experienced by thirty-one of the thirty-three patients with positive skin tests were immediate in onset (within 1 hr) and were at first confined to the upper gastrointestinal tract, the most frequent symptoms being oral irritation and throat tightness. In a proportion of these patients, further symptoms such as urticaria, asthma or anaphylaxis developed following the initial oral symptoms, which suggested the term 'oral allergy syndrome'. In the absence of the oral allergy, symptoms such as asthma, urticaria, migraine or eczema starting later than 1 hr after food were seldom associated with positive skin tests. In the oral allergy syndrome, the characteristic symptoms (strong association with positive skin tests and RAST, time of onset and sites at which symptoms are expressed) suggest a causative relationship between exposure to food antigens and specific IgE-induced release of mediators. In cases of food intolerance that lack a characteristic symptom pattern and a positive skin test or radio-allergo-sorbent test, it seems appropriate to consider non-IgE-mediated causes. PMID:3829369

  9. Cyclooxygenases 1 and 2 contribute to peroxynitrite-mediated inflammatory pain hypersensitivity.

    PubMed

    Ndengele, Michael M; Cuzzocrea, Salvatore; Esposito, Emanuela; Mazzon, Emanuela; Di Paola, Rosanna; Matuschak, George M; Salvemini, Daniela

    2008-09-01

    Peroxynitrite (ONOO(-)), the reaction product of the interaction between superoxide (O(2)(*-)) and nitric oxide (*NO), is a potent proinflammatory and cytotoxic nitrooxidative species. Its role as a mediator of hyperalgesia (clinically defined as an augmented sensitivity to painful stimuli) is not known. In light of the known proinflammatory properties of ONOO(-), our study addressed its potential involvement in the development of hyperalgesia associated with tissue damage and inflammation. Intraplantar injection in rats of the ONOO(-) precursor O(2)(*-) (1 microM) led to the development of thermal hyperalgesia associated with a profound localized inflammatory response. Both events were blocked by L-NAME (N(G)-nitro-L-arginine methyl ester, 3-30 mg/kg), a nitric oxide synthase inhibitor, or by FeTM-4-PyP(5+) [Fe(III)5,10,15,20-tetrakis(N-methylpyridinium-4-yl)porphyrin, 3-30 mg/kg], an ONOO(-) decomposition catalyst. These results suggested that locally synthesized ONOO(-) produced in situ by O(2)(*-) and *NO is key in the development of inflammatory hyperalgesia. The direct link between ONOO(-) and hyperalgesia was further supported by demonstrating that intraplantar injection of soluble ONOO(-) itself (1 microM) similarly led to inflammatory hyperalgesia. ONOO(-) generated by the interaction between exogenous administration of O(2)(*-) and endogenous *NO, or provided by direct injection of ONOO(-), activated the transcription factor NF-kappaB in paw tissues, enhancing expression of the inducible but not the constitutive cyclooxygenase enzyme (COX-2 and COX-1, respectively). ONOO(-)-mediated hyperalgesia was blocked in a dose-dependent manner by intraperitoneal injections of indomethacin (10 mg/kg), a nonselective COX-1/COX-2 inhibitor, or NS398 [N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide; 10 mg/kg] a selective COX-2 inhibitor, as well as by an anti-prostaglandin (PG) E(2) antibody (200 microg). In another established model of inflammation

  10. Cell-mediated immunity in nutritional deficiency.

    PubMed

    McMurray, D N

    1984-01-01

    Dietary deficiencies of specific nutrients profoundly alter cell-mediated immune responses in man and experimental animals. Both moderate and severe deficiencies are associated with significant changes in immunocompetence. Diets with inadequate levels of protein, calories, vitamin A, pyridoxine, biotin and zinc result in loss of thymic cellularity. Secondary to thymic atrophy, the production of thymic hormones critical for the differentiation of T lymphocytes is reduced, especially in protein-calorie malnutrition and zinc deficiency. Confirmation of a T cell maturational defect in nutritional deprivation comes from the observations of decreased total (T3 and rosette-forming) T cells in the peripheral blood of children with kwashiorkor and marasmus, with preferential loss of helper/inducer (T4) T cell subsets. Reduced number and in vitro function of T cells have also been reported in experimental deficiencies of iron, zinc, copper, and vitamins A and E. Loss of cutaneous hypersensitivity to mitogens and antigens is a consistent sequela of dietary deficiencies of protein, vitamins A and C, pyridoxine, iron and zinc. Cell-mediated immunity directed against allogeneic histocompatibility antigens (e.g. mixed leukocyte cultures, graft versus host, skin graft rejection) may actually be enhanced by experimental protein and polyunsaturated fat deficiencies. Alternatively, pyridoxine, ascorbate and biotin deficiencies resulted in delayed rejection of skin allografts. Cytotoxic T lymphocyte (CTL) activity is impaired in zinc-, iron- and copper-deficient mice, as well as in scorbutic guinea pigs. Natural killer (NK) cell function may be either enhanced or depressed, depending upon the nutrient and its effects on interferon production. Several authors have demonstrated normal or enhanced macrophage activity in a variety of experimental deficiencies. The extrapolation of these observations to infectious disease resistance is not straightforward, and depends upon the nature of

  11. Pb exposure attenuates hypersensitivity in vivo by increasing regulatory T cells

    SciTech Connect

    Fang, Liang; Zhao, Fang; Shen, Xuefeng; Ouyang, Weiming; Liu, Xinqin; Xu, Yan; Yu, Tao; Jin, Boquan; Chen, Jingyuan; Luo, Wenjing

    2012-12-01

    Pb is a common environmental pollutant affecting various organs. Exposure of the immune system to Pb leads to immunosuppression or immunodysregulation. Although previous studies showed that Pb exposure can modulate the function of helper T cells, Pb immunotoxicity remains incompletely understood. In this study, we investigated the effect of Pb exposure on T cell development, and the underlying mechanism of Pb-induced suppression of the delayed-type hypersensitivity (DTH) response in vivo. Sprague–Dawley rats were exposed to 300 ppm Pb-acetate solution via the drinking water for six weeks, and we found that Pb exposure significantly increased Pb concentrations in the blood by 4.2-fold (p < 0.05) as compared to those in the control rats. In Pb-exposed rats, the amount of thymic CD4{sup +}CD8{sup −} and peripheral CD4{sup +} T cells was significantly reduced, whereas, CD8{sup +} population was not affected. In contrast to conventional CD4{sup +} T cells, Foxp3{sup +} regulatory T cells (Tregs) were increased in both the thymus and peripheral lymphoid organs of Pb-exposed rats. In line with the increase of Tregs, the DTH response of Pb-exposed rats was markedly suppressed. Depletion of Tregs reversed the suppression of DTH response by Pb-exposed CD4{sup +} T cells in an adoptive transfer model, suggesting a critical role of the increased Tregs in suppressing the DTH response. Collectively, this study revealed that Pb-exposure may upregulate Tregs, thereby leading to immunosuppression. -- Highlights: ► Pb exposure impaired CD4{sup +} thymic T cell development. ► Peripheral T lymphocytes were reduced following Pb exposure. ► Pb exposure increases thymic and peripheral Treg cells in rats. ► Tregs played a critical role in Pb-exposure-induced immune suppression.

  12. Hypersensitivity pneumonitis

    MedlinePlus

    Hypersensitivity pneumonitis usually occurs in people who work in places where there are high levels of organic dusts, fungus, or molds. Long-term exposure can lead to lung inflammation and acute lung disease . ...

  13. Hypersensitivity Pneumonitis

    MedlinePlus

    ... Hypersensitivity Pneumonitis Also known as extrinsic allergic alveolitis, bird fancier’s lung, farmer’s lung, hot tub lung, and ... May 27, 2016 Twitter Facebook YouTube Google+ SITE INDEX ACCESSIBILITY PRIVACY STATEMENT FOIA OIG CONTACT US National ...

  14. Immunosuppressive Effect of Litsea cubeba L. Essential Oil on Dendritic Cell and Contact Hypersensitivity Responses

    PubMed Central

    Chen, Hsin-Chun; Chang, Wen-Te; Hseu, You-Cheng; Chen, Hsing-Yu; Chuang, Cheng Hsuan; Lin, Chi-Chen; Lee, Meng-Shiou; Lin, Ming-Kuem

    2016-01-01

    Litsea cubeba L., also named as Makauy, is a traditional herb and has been used as cooking condiment or tea brewing to treat diseases for aborigines. The present study was undertaken to explore the chemical compositions of the fruit essential oil of L. cubeba (LCEO) and the immunomodulatory effect of LCEO on dendritic cells and mice. The LCEO was analyzed using gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) with direct injection (DI/GC) or headspace-solid phase microextraction (HS-SPME/GC). In total, 56 components were identified, of which 48 were detected by DI/GC and 49 were detected by HS-SPME/GC. The principal compounds were citral (neral and geranial). An immunosuppressive activity of LCEO was investigated with bone marrow-derived dendritic cells (DCs) which have a critical role to trigger the adaptive immunity. Additionally, the inhibitory effect of LCEO on immune response was elucidated by performing the contact hypersensitivity (CHS) responses in mice. Our results clearly showed that LCEO decreases the production of TNF-α and cytokine IL-12 in a dose-dependent manner in lipopolysaccharide (LPS)-stimulated DCs. CHS response and the infiltrative T cells were inhibited in the tested ears of the mice co-treated with LCEO. We demonstrate, for the first time, that the LCEO mainly containing citral exhibits an immunosuppressive effect on DCs and mice, indicating that LCEO can potentially be applied in the treatment of CHS, inflammatory diseases, and autoimmune diseases. PMID:27529236

  15. Immunosuppressive Effect of Litsea cubeba L. Essential Oil on Dendritic Cell and Contact Hypersensitivity Responses.

    PubMed

    Chen, Hsin-Chun; Chang, Wen-Te; Hseu, You-Cheng; Chen, Hsing-Yu; Chuang, Cheng Hsuan; Lin, Chi-Chen; Lee, Meng-Shiou; Lin, Ming-Kuem

    2016-01-01

    Litsea cubeba L., also named as Makauy, is a traditional herb and has been used as cooking condiment or tea brewing to treat diseases for aborigines. The present study was undertaken to explore the chemical compositions of the fruit essential oil of L. cubeba (LCEO) and the immunomodulatory effect of LCEO on dendritic cells and mice. The LCEO was analyzed using gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) with direct injection (DI/GC) or headspace-solid phase microextraction (HS-SPME/GC). In total, 56 components were identified, of which 48 were detected by DI/GC and 49 were detected by HS-SPME/GC. The principal compounds were citral (neral and geranial). An immunosuppressive activity of LCEO was investigated with bone marrow-derived dendritic cells (DCs) which have a critical role to trigger the adaptive immunity. Additionally, the inhibitory effect of LCEO on immune response was elucidated by performing the contact hypersensitivity (CHS) responses in mice. Our results clearly showed that LCEO decreases the production of TNF-α and cytokine IL-12 in a dose-dependent manner in lipopolysaccharide (LPS)-stimulated DCs. CHS response and the infiltrative T cells were inhibited in the tested ears of the mice co-treated with LCEO. We demonstrate, for the first time, that the LCEO mainly containing citral exhibits an immunosuppressive effect on DCs and mice, indicating that LCEO can potentially be applied in the treatment of CHS, inflammatory diseases, and autoimmune diseases. PMID:27529236

  16. Expression of BRC repeats in breast cancer cells disrupts the BRCA2-Rad51 complex and leads to radiation hypersensitivity and loss of G(2)/M checkpoint control.

    PubMed

    Chen, C F; Chen, P L; Zhong, Q; Sharp, Z D; Lee, W H

    1999-11-12

    BRCA2 is a breast tumor suppressor with a potential function in the cellular response to DNA damage. BRCA2 binds to Rad51 through its BRC repeats. In support of the biological significance of this interaction, we found that the complex of BRCA2 and Rad51 in breast cancer MCF-7 cells was diminished upon conditional expression of a wild-type, but not a mutated, BRC4 repeat using the tetracycline-inducible system. Cells expressing a wild-type BRC4 repeat showed hypersensitivity to gamma-irradiation, an inability to form Rad51 radiation-induced foci, and a failure of radiation-induced G(2)/M, but not G(1)/S, checkpoint control. These results strongly suggest that the interaction between BRCA2 and Rad51 mediated by BRC repeats is critical for the cellular response to DNA damage.

  17. The hypersensitive induced reaction and leucine-rich repeat proteins regulate plant cell death associated with disease and plant immunity.

    PubMed

    Choi, Hyong Woo; Kim, Young Jin; Hwang, Byung Kook

    2011-01-01

    Pathogen-induced programmed cell death (PCD) is intimately linked with disease resistance and susceptibility. However, the molecular components regulating PCD, including hypersensitive and susceptible cell death, are largely unknown in plants. In this study, we show that pathogen-induced Capsicum annuum hypersensitive induced reaction 1 (CaHIR1) and leucine-rich repeat 1 (CaLRR1) function as distinct plant PCD regulators in pepper plants during Xanthomonas campestris pv. vesicatoria infection. Confocal microscopy and protein gel blot analyses revealed that CaLRR1 and CaHIR1 localize to the extracellular matrix and plasma membrane (PM), respectively. Bimolecular fluorescent complementation and coimmunoprecipitation assays showed that the extracellular CaLRR1 specifically binds to the PM-located CaHIR1 in pepper leaves. Overexpression of CaHIR1 triggered pathogen-independent cell death in pepper and Nicotiana benthamiana plants but not in yeast cells. Virus-induced gene silencing (VIGS) of CaLRR1 and CaHIR1 distinctly strengthened and compromised hypersensitive and susceptible cell death in pepper plants, respectively. Endogenous salicylic acid levels and pathogenesis-related gene transcripts were elevated in CaHIR1-silenced plants. VIGS of NbLRR1 and NbHIR1, the N. benthamiana orthologs of CaLRR1 and CaHIR1, regulated Bax- and avrPto-/Pto-induced PCD. Taken together, these results suggest that leucine-rich repeat and hypersensitive induced reaction proteins may act as cell-death regulators associated with plant immunity and disease.

  18. Transcription of the hypersensitive site HS2 enhancer in erythroid cells.

    PubMed Central

    Tuan, D; Kong, S; Hu, K

    1992-01-01

    In the human genome, the erythroid-specific hypersensitive site HS2 enhancer regulates the transcription of the downstream beta-like globin genes 10-50 kilobases away. The mechanism of HS2 enhancer function is not known. The present study employs RNA protection assays to analyze the transcriptional status of the HS2 enhancer in transfected recombinant chloramphenicol acetyltransferase (CAT) plasmids. In erythroid K562 cells in which the HS2 enhancer is active, the HS2 sequence directs the synthesis of long enhancer transcripts that are initiated apparently from within the enhancer and elongated through the intervening DNA into the cis-linked CAT gene. In nonerythroid HL-60 cells in which the HS2 enhancer is inactive, long enhancer transcripts are not detectable. Splitting the HS2 enhancer between two tandem Ap1 sites abolishes the synthesis of a group of long enhancer transcripts and results in loss of enhancer function and transcriptional silencing of the cis-linked CAT gene. In directing the synthesis of RNA through the intervening DNA and the gene by a tracking and transcription mechanism, the HS2 enhancer may (i) open up the chromatin structure of a gene domain and (ii) deliver enhancer binding proteins to the promoter sequence where they may stimulate the transcription of the gene at the cap site. Images PMID:1454801

  19. Transcription of the hypersensitive site HS2 enhancer in erythroid cells

    SciTech Connect

    Tuan, D.; Suming Kong; Hu, K. )

    1992-12-01

    In the human genome, the erythroid-specific hypersensitive site HS2 enhancer regulates the transcription of the downstream [beta]-like globin genes 10-50 kilobases away. The mechanism of HS2 enhancer function is not known. The present study employs RNA protection assays to analyze the transcriptional status of the HS2 enhancer in transfected recombinant chloramphenicol acetyltransferase (CAT) plasmids. In erythroid K562 cells in which the HS2 enhancer is active, the HS2 sequence directs the synthesis of long enhancer transcripts that are initiated apparently from within the enhancer and elongated through the intervening DNA into the cis-linked CAT gene. In nonerythroid HL-60 cells in which the HS2 enhancer is inactive, long enhancer transcripts are not detectable. Splitting the HS2 enhancer between two tandem Ap1 sites abolishes the synthesis of a group of long enhancer transcripts and results in loss of enhancer function and transcriptional silencing of the cis-linked CAT gene. In directing the synthesis of RNA through the intervening DNA and the gene by a tracking and transcription mechanism, the HS2 enhancer may (i) open up the chromatin structure of a gene domain and (ii) deliver enhancer binding proteins to the promoter sequence where they may stimulate the transcription of the gene at the cap site. 42 refs., 4 figs., 1 tab.

  20. Anaplastic lymphoma kinase-positive anaplastic large cell lymphoma arising in a patient with hypersensitivity to mosquito bites.

    PubMed

    Kang, Jin Hee; Lee, Ji Hae; Kim, Miri; Cho, Baik Kee; Song, Chan Hee; Ock, Sun Myeong; Park, Hyun Jeong

    2015-01-01

    Hypersensitivity to mosquito bites is defined as the appearance of intense skin reactive lesions and systemic symptoms subsequent to mosquito bites. Most cases of hypersensitivity to mosquito bites reported thus far have been associated with chronic Epstein-Barr virus infection or natural killer cell leukemia/lymphoma. In this study, we describe the case of an 18-year-old Korean boy who had hypersensitivity to mosquito bites associated with primary systemic anaplastic lymphoma kinase-positive anaplastic large cell lymphoma. After a mosquito bite, the patient developed a progressive cutaneous nodule on his left lower leg and regional lymphadenopathy in the left inguinal area. The histopathological and immunohistochemical findings suggested anaplastic lymphoma kinase-positive anaplastic large cell lymphoma. Positron emission tomography-computed tomography revealed increased fluorodeoxyglucose uptake in the left T4 vertebrae, left external iliac lymph nodes, left inguinal lymph nodes, and lateral subcutaneous region of the left lower leg. According to the clinical, histopathological, and immunohistochemical findings, as well as the imaging data, the patient was diagnosed with primary systemic anaplastic lymphoma kinase-positive anaplastic large cell lymphoma. Consequently, the patient received a total of 6 cycles of cyclophosphamide + doxorubicin + vincristine + prednisolone chemotherapy at 3-week intervals, after which the lesions regressed.

  1. Testing for Drug Hypersensitivity Syndromes

    PubMed Central

    Rive, Craig M; Bourke, Jack; Phillips, Elizabeth J

    2013-01-01

    Adverse drug reactions are a common cause of patient morbidity and mortality. Type B drug reactions comprise only 20% of all drug reactions but they tend to be primarily immunologically mediated and less dependent on the drug’s pharmacological action and dose. Common Type B reactions seen in clinical practice are those of the immediate, IgE, Gell-Coombs Type I reactions, and the delayed, T-cell mediated, Type IV reactions. Management of these types of reactions, once they have occurred, requires careful consideration and recognition of the utility of routine diagnostic tests followed by ancillary specialised diagnostic testing. For Type I, IgE mediated reactions this includes prick/intradermal skin testing and oral provocation. For Type IV, T-cell mediated reactions this includes a variety of in vivo (patch testing) and ex vivo tests, many of which are currently mainly used in highly specialised research laboratories. The recent association of many serious delayed (Type IV) hypersensitivity reactions to specific drugs with HLA class I and II alleles has created the opportunity for HLA screening to exclude high risk populations from exposure to the implicated drug and hence prevent clinical reactions. For example, the 100% negative predictive value of HLA-B*5701 for true immunologically mediated abacavir hypersensitivity and the development of feasible, inexpensive DNA-based molecular tests has led to incorporation of HLA-B*5701 screening in routine HIV clinical practice. The mechanism by which drugs specifically interact with HLA has been recently characterised and promises to lead to strategies for pre-clinical screening to inform drug development and design. PMID:23592889

  2. Formulated extract from multiple citrus peels impairs dendritic cell functions and attenuates allergic contact hypersensitivity.

    PubMed

    Li, Shiming; Lin, Yi-Chin; Ho, Chi-Tang; Lin, Ping-Yi; Suzawa, Michiko; Wang, Hsin-Chieh; Chu, Ching-Liang; Chen, Der-Yuan; Lin, Chi-Chen

    2014-05-01

    It has been reported that gold lotion (GL), a formulated product made from the peels of six citrus fruits, has many pharmacological properties, such as anti-tumor, antioxidant, and anti-inflammatory activities. In this study, we investigated the immunomodulatory effect of GL on lipopolysaccharide (LPS) stimulated mouse bone marrow-derived DC maturation and function. Our experimental results have shown that GL significantly impaired the pro-inflammatory cytokine and chemokine secretion, suppressed the expression of major histocompatibility complex class I/II and costimulatory molecules (CD40, CD80 and CD86), increased phagocytic capacity, and reduced propensity to stimulate the autologous CD4(+) and CD8(+) T cell proliferation of LPS-induced DCs. Furthermore, we found that oral administration of GL attenuated the 2,4-Dinitro-1-fluorobenzene induced contact hypersensitivity (CHS) in animal models. Subsequently, our molecular mechanism studies showed that GL interfered with LPS-induced MAPK-JNK, p38 phosphorylation and nuclear translocation of NF-κB p65. In an essence, these findings are the first report to provide new insight in the immunopharmacological role of GL in terms of its effects on DC.

  3. Formulated extract from multiple citrus peels impairs dendritic cell functions and attenuates allergic contact hypersensitivity.

    PubMed

    Li, Shiming; Lin, Yi-Chin; Ho, Chi-Tang; Lin, Ping-Yi; Suzawa, Michiko; Wang, Hsin-Chieh; Chu, Ching-Liang; Chen, Der-Yuan; Lin, Chi-Chen

    2014-05-01

    It has been reported that gold lotion (GL), a formulated product made from the peels of six citrus fruits, has many pharmacological properties, such as anti-tumor, antioxidant, and anti-inflammatory activities. In this study, we investigated the immunomodulatory effect of GL on lipopolysaccharide (LPS) stimulated mouse bone marrow-derived DC maturation and function. Our experimental results have shown that GL significantly impaired the pro-inflammatory cytokine and chemokine secretion, suppressed the expression of major histocompatibility complex class I/II and costimulatory molecules (CD40, CD80 and CD86), increased phagocytic capacity, and reduced propensity to stimulate the autologous CD4(+) and CD8(+) T cell proliferation of LPS-induced DCs. Furthermore, we found that oral administration of GL attenuated the 2,4-Dinitro-1-fluorobenzene induced contact hypersensitivity (CHS) in animal models. Subsequently, our molecular mechanism studies showed that GL interfered with LPS-induced MAPK-JNK, p38 phosphorylation and nuclear translocation of NF-κB p65. In an essence, these findings are the first report to provide new insight in the immunopharmacological role of GL in terms of its effects on DC. PMID:24566093

  4. Identification of genes required for Cf-dependent hypersensitive cell death by combined proteomic and RNA interfering analyses

    PubMed Central

    Xu, Qiu-Fang; Cheng, Wei-Shun; Zhang, Zhi-Xin; Xu, You-Ping; Zhou, Xue-Ping; Cai, Xin-Zhong

    2012-01-01

    Identification of hypersensitive cell death (HCD) regulators is essential to dissect the molecular mechanisms underlying plant disease resistance. In this study, combined proteomic and RNA interfering (RNAi) analyses were employed to identify genes required for the HCD conferred by the tomato resistance gene Cf-4 and the Cladosporium fulvum avirulence gene Avr4. Forty-nine proteins differentially expressed in the tomato seedlings mounting and those not mounting Cf-4/Avr4-dependent HCD were identified through proteomic analysis. Among them were a variety of defence-related proteins including a cysteine protease, Pip1, an operative target of another C. fulvum effector, Avr2. Additionally, glutathione-mediated antioxidation is a major response to Cf-4/Avr4-dependent HCD. Functional analysis through tobacco rattle virus-induced gene silencing and transient RNAi assays of the chosen 16 differentially expressed proteins revealed that seven genes, which encode Pip1 homologue NbPip1, a SIPK type MAP kinase Nbf4, an asparagine synthetase NbAsn, a trypsin inhibitor LeMir-like protein NbMir, a small GTP-binding protein, a late embryogenesis-like protein, and an ASR4-like protein, were required for Cf-4/Avr4-dependent HCD. Furthermore, the former four genes were essential for Cf-9/Avr9-dependent HCD; NbPip1, NbAsn, and NbMir, but not Nbf4, affected a nonadaptive bacterial pathogen Xanthomonas oryzae pv. oryzae-induced HCD in Nicotiana benthamiana. These data demonstrate that Pip1 and LeMir may play a general role in HCD and plant immunity and that the application of combined proteomic and RNA interfering analyses is an efficient strategy to identify genes required for HCD, disease resistance, and probably other biological processes in plants. PMID:22275387

  5. Separation by column chromatography of cells active in delayed-onset hypersensitivities.

    PubMed Central

    Godfrey, H P; Gell, P G

    1976-01-01

    Lymph node cells from guinea-pigs contact sensitive to 1-thiocyamo-2,4-dinitrobenzene have been fractionated by affinity chromatography over modified polyacrylamide beads. Cells mediating lymphokine release in response to active sensitizer were depleted only by chromatography over dinitrophyenyl (DNP) containing substrates and could be specifically eluted with DNP-glycine. DNP rosette-forming cells (RFC) were equally well depleted by chromatography using either DNP or trinitrophenyl containing materials but could not be eluted from the columns by DNP-glycine. While the antigen receptors of cells mediating the release of macrophage agglutination factor in response to DNP-containing antigens and of DNP-RFC were found to be hapten-specific, their specificity was shown to differ using chromatography over trinitrophenyl containing polyacrylamide. PMID:776818

  6. TRPV1-mediated presynaptic transmission in basolateral amygdala contributes to visceral hypersensitivity in adult rats with neonatal maternal deprivation

    PubMed Central

    Xiao, Ying; Chen, Xiaoqi; Zhang, Ping-An; Xu, Qiya; Zheng, Hang; Xu, Guang-Yin

    2016-01-01

    The central mechanisms of visceral hypersensitivity remain largely unknown. It’s reported that there are highest densities of TRPV1 labeled neurons within basolateral amygdala (BLA). The aim of this study was to explore the role and mechanisms of TRPV1 in BLA in development of visceral hypersensitivity. Visceral hypersensitivity was induced by neonatal maternal deprivation (NMD) and was quantified by abdominal withdrawal reflex. Expression of TRPV1 was determined by Western blot. The synaptic transmission of neurons in BLA was recorded by patch clamping. It was found that the expression of TRPV1 in BLA was significantly upregulated in NMD rats; glutamatergic synaptic activities in BLA were increased in NMD rats; application of capsazepine (TRPV1 antagonist) decreased glutamatergic synaptic activities of BLA neurons in NMD slices through a presynaptic mechanism; application of capsaicin (TRPV1 agonist) increased glutamatergic synaptic activities of BLA neurons in control slices through presynaptic mechanism without affecting GABAergic synaptic activities; microinjecting capsazepine into BLA significantly increased colonic distension threshold both in control and NMD rats. Our data suggested that upregulation of TRPV1 in BLA contributes to visceral hypersensitivity of NMD rats through enhancing excitation of BLA, thus identifying a potential target for treatment of chronic visceral pain. PMID:27364923

  7. Hypersensitivity reactions to iodinated contrast media.

    PubMed

    Guéant-Rodriguez, Rosa-Maria; Romano, Antonino; Barbaud, Annick; Brockow, Knut; Guéant, Jean-Louis

    2006-01-01

    Adverse reactions after iodinate contrast media (ICM) administration have been observed, which can be classified as immediate (i.e., occurring within one hour after administration) and delayed or non-immediate (i.e., occurring more than one hour after administration). Even though the incidence of ICM adverse reactions has been significantly reduced by the introduction of non-ionic compounds, immediate reactions still occur in about 3% of administrations. Different pathogenic mechanisms have been suggested for ICM reactions, including immunologic ones. Basophils and mast cells participate in immediate reactions through the release of mediators like histamine and tryptase, whereas a T-cell-mediated pathogenic mechanism is involved in most non-immediate reactions, particularly maculopapular rashes. Skin tests and specific IgE assays are carried out to diagnose immediate hypersensitivity reactions, while both delayed-reading intradermal tests and patch tests are usually performed to evaluate non-immediate reactions. However, in vitro specific IgE assays are not commercially available. As far as in vitro tests are concerned, a response involving ICM-related T-cell activity may be assessed by the lymphocyte transformation test. Allergologic evaluation appears to be indicated in hypersensitivity reactions to ICM, although the sensitivity, specificity, and predictive values of allergologic tests have not yet been established. This paper summarizes the current state of the art and addresses the research that is still needed on the pathogenic mechanisms, diagnosis, and prevention of ICM-induced hypersensitivity reactions.

  8. Hypersensitivity Pneumonitis.

    PubMed

    Wysong, Kristi; Phillips, Jennan A; Hammond, Stephanie

    2016-06-01

    Chronic exposure to a broad array of antigens after workers inhale aerosolized organic dust particles from mold, animal dander, bird droppings, and chemicals, especially pesticides or herbicides, increases risk for hypersensitivity pneumonitis. Several demographic characteristics of immigrant workers in farming, poultry processing, construction, and landscaping increase this worker population's risk. PMID:27067273

  9. Hypersensitivity Pneumonitis.

    PubMed

    Wysong, Kristi; Phillips, Jennan A; Hammond, Stephanie

    2016-06-01

    Chronic exposure to a broad array of antigens after workers inhale aerosolized organic dust particles from mold, animal dander, bird droppings, and chemicals, especially pesticides or herbicides, increases risk for hypersensitivity pneumonitis. Several demographic characteristics of immigrant workers in farming, poultry processing, construction, and landscaping increase this worker population's risk.

  10. Cell-mediated immune responses to COPV early proteins.

    PubMed

    Jain, Suchitra; Moore, Richard A; Anderson, Davina M; Gough, Gerald W; Stanley, Margaret A

    Cell-mediated immunity plays a key role in the regression of papillomavirus-induced warts and intra-epithelial lesions but the target antigens that induce this response are not clear. Canine oral papillomavirus (COPV) infection of the oral cavity in dogs is a well-characterized model of mucosal papillomavirus infection that permits analysis of the immune events during the infectious cycle. In this study we show that during the COPV infectious cycle, systemic T cell responses to peptides of several early proteins particularly the E2 protein, as assayed by delayed type hypersensitivity, lymphoproliferation and IFN-gamma ELISPOT, can be detected. The maximal response occurs in a narrow time window that coincides with maximal viral DNA replication and wart regression: thereafter, systemic T cell responses to early proteins decline quite rapidly. Vaccination using particle-mediated immunotherapeutic delivery (PMID) of codon-modified COPV E2 and E1 genes induces strong antigen-specific cell-mediated immune responses in the vaccinated animals. These data show that therapeutic immunization by PMID with codon-modified E2 is completely effective, that to E1 is partially protective, that this correlates with the intensity of antigen-specific cell-mediated immune responses and, further, they emphasize the importance of these responses and the route of immunization in the generation of protective immunity. PMID:16949120

  11. Dentine hypersensitivity.

    PubMed

    West, Nicola; Seong, Joon; Davies, Maria

    2014-01-01

    Dentine hypersensitivity is a common oral pain condition affecting many individuals. The aetiology is multifactorial; however, over recent years the importance of erosion has become more evident. For dentine hypersensitivity to occur, the lesion must first be localised on the tooth surface and then initiated to exposed dentine tubules which are patent to the pulp. The short, sharp pain symptom is thought to be derived from the hydrodynamic pain theory and, although transient, is arresting, affecting quality of life. This episodic pain condition is likely to become a more frequent dental complaint in the future due to the increase in longevity of the dentition and the rise in tooth wear, particularly amongst young adults. Many efficacious treatment regimens are now available, in particular a number of over-the-counter home use products. The basic principles of treatment are altering fluid flow in the dentinal tubules with tubule occlusion or modifying or chemically blocking the pulpal nerve. PMID:24993261

  12. Transient receptor potential vanilloid 1 mediates pain in mice with severe sickle cell disease

    PubMed Central

    Kerstein, Patrick C.; Vilceanu, Daniel; Barabas, Marie E.; Retherford, Dawn; Brandow, Amanda M.; Wandersee, Nancy J.

    2011-01-01

    Pain is the leading cause of emergency department visits, hospitalizations, and daily suffering in individuals with sickle cell disease (SCD). The pathologic mechanisms leading to the perception of pain during acute RBC sickling episodes and development of chronic pain remain poorly understood and ineffectively treated. We provide the first study that explores nociceptor sensitization mechanisms that contribute to pain behavior in mice with severe SCD. Sickle mice exhibit robust behavioral hypersensitivity to mechanical, cold, and heat stimuli. Mechanical hypersensitivity is further exacerbated when hypoxia is used to induce acute sickling. Behavioral mechanical hypersensitivity is mediated in part by enhanced excitability to mechanical stimuli at both primary afferent peripheral terminal and sensory membrane levels. In the present study, inhibition of the capsaicin receptor transient receptor potential vanilloid 1 (TRPV1) with the selective antagonist A-425619 reversed the mechanical sensitization at both primary afferent terminals and isolated somata, and markedly attenuated mechanical behavioral hypersensitivity. In contrast, inhibition of TRPA1 with HC-030031 had no effect on mechanical sensitivity. These results suggest that the TRPV1 receptor contributes to primary afferent mechanical sensitization and a substantial portion of behavioral mechanical hypersensitivity in SCD mice. Therefore, TRPV1-targeted compounds that lack thermoregulatory side effects may provide relief from pain in patients with SCD. PMID:21708890

  13. [Dentinal hypersensitivity].

    PubMed

    Steinkeller-Dekel, M; Smidt, A; Pilo, R

    2010-01-01

    Dentinal hypersensitivity is defined as short and transient painful response of exposed dentin, usually cervical, to different stimuli, such as thermal, mechanical osmotic or chemical. The etiology of dentinal hypersensitivity is open tubules (because of enamel loss or gingival recession), allowing painful stimulus to reach the pulp. The hydrodynamic theory explains the mechanism through which pain is aroused. When treating dentinal hypersensitivity, dentists always have to rule out other pathologies, such as carries, leakage, postoperative sensitivity, cracked tooth etc., and only then assess pain intensity and treat the tooth. Treatment always starts with prevention of both stimulus and exposure of dentin, and reducing predisposing factors. The treatment options include OTC products, such as fluoride and/or potassium enriched mouth washes and dentifrices, or in-office treatments, such as high content fluoride varnishes and gels, potassium oxalate chelating agents, Glutaraldehyde containing tissue fixating agents, bonding materials, low viscosity glass ionomers and even non-conservative treatments such as root canal therapy or mucogingival surgical interventions.

  14. [Dentinal hypersensitivity].

    PubMed

    Steinkeller-Dekel, M; Smidt, A; Pilo, R

    2010-01-01

    Dentinal hypersensitivity is defined as short and transient painful response of exposed dentin, usually cervical, to different stimuli, such as thermal, mechanical osmotic or chemical. The etiology of dentinal hypersensitivity is open tubules (because of enamel loss or gingival recession), allowing painful stimulus to reach the pulp. The hydrodynamic theory explains the mechanism through which pain is aroused. When treating dentinal hypersensitivity, dentists always have to rule out other pathologies, such as carries, leakage, postoperative sensitivity, cracked tooth etc., and only then assess pain intensity and treat the tooth. Treatment always starts with prevention of both stimulus and exposure of dentin, and reducing predisposing factors. The treatment options include OTC products, such as fluoride and/or potassium enriched mouth washes and dentifrices, or in-office treatments, such as high content fluoride varnishes and gels, potassium oxalate chelating agents, Glutaraldehyde containing tissue fixating agents, bonding materials, low viscosity glass ionomers and even non-conservative treatments such as root canal therapy or mucogingival surgical interventions. PMID:20597258

  15. Notch-Mediated Cell Adhesion

    PubMed Central

    Murata, Akihiko; Hayashi, Shin-Ichi

    2016-01-01

    Notch family members are generally recognized as signaling molecules that control various cellular responses in metazoan organisms. Early fly studies and our mammalian studies demonstrated that Notch family members are also cell adhesion molecules; however, information on the physiological roles of this function and its origin is limited. In this review, we discuss the potential present and ancestral roles of Notch-mediated cell adhesion in order to explore its origin and the initial roles of Notch family members dating back to metazoan evolution. We hypothesize that Notch family members may have initially emerged as cell adhesion molecules in order to mediate multicellularity in the last common ancestor of metazoan organisms. PMID:26784245

  16. Sensitization of P2X3 receptors by cystathionine β-synthetase mediates persistent pain hypersensitivity in a rat model of lumbar disc herniation.

    PubMed

    Wang, Qianliang; Zhu, Hongyan; Zou, Kang; Yuan, Bo; Zhou, You-Lang; Jiang, Xinghong; Yan, Jun; Xu, Guang-Yin

    2015-03-20

    Lumbar disc herniation (LDH) is a major cause of discogenic low back pain and sciatica, but the underlying mechanisms remain largely unknown. Hydrogen sulfide (H2S) is becoming recognized for its involvement in a wide variety of processes including inflammation and nociception. The present study was designed to investigate the roles of the H2S signaling pathway in the regulation of expression and function of purinergic receptors (P2XRs) in dorsal root ganglion (DRG) neurons from rats with LDH. LDH was induced by implantation of autologous nucleus pulposus (NP), harvested from rat tail, in lumbar 5 and 6 spinal nerve roots. Implantation of autologous NP induced persistent pain hypersensitivity, which was partially reversed by an intrathecal injection of A317491, a potent inhibitor of P2X3Rs and P2X2/3Rs. The NP induced persistent pain hypersensitivity was associated with the increased expression of P2X3Rs, but not P2X1Rs and P2X2Rs, receptors in L5-6 DRGs. NP implantation also produced a 2-fold increase in ATP-induced intracellular calcium signals in DRG neurons when compared to those of controls (P < 0.05). Interestingly, NP implantation significantly enhanced expression of the endogenous hydrogen sulfide producing enzyme, cystathionine-β-synthetase (CBS). Systematic administration of O-(Carboxymethyl) hydroxylamine hemihydrochloride (AOAA), an inhibitor of CBS, suppressed the upregulation of P2X3R expression and the potentiation of ATP-induced intracellular calcium signals in DRG neurons (P < 0.05). Intrathecal injection of AOAA markedly attenuated NP induced- persistent pain hypersensitivity. Our results suggest that sensitization of P2X3Rs, which is likely mediated by CBS-H2S signaling in primary sensory neurons, contributes to discogenic pain. Targeting CBS/H2S-P2X3R signaling may represent a potential treatment for neuropathic pain caused by LDH.

  17. Cell-mediated immune reactions to clinical neuroblastoma.

    PubMed

    Okabe, I; Kurosu, Y; Morita, K

    1985-09-01

    Immunotherapy may be an effective treatment for neuroblastoma. It is of importance to delineate changes in various parameters of tumor immunity over an extended period, before and during the course of treatment, in any given case. In our patients with neuroblastoma, tumor-associated cell-mediated immune-reaction showed a good responsiveness before treatment. However, delayed cutaneous hypersensitivity reactions were shown to be negative in many cases, particularly in those with advanced tumor, and T gamma cells were enormously increased in some cases. During the course of therapy, the tumor-associated cellular immune responsiveness showed a tendency to become negative when the patient was tumor free or was in remission, but showed a tendency to become positive on regrowth, recurrence or metastasis of tumor. The T gamma cells showed much the same fluctuations as did the tumor-associated cellular immune responsiveness.

  18. Loss of ubiquitin E2 Ube2w rescues hypersensitivity of Rnf4 mutant cells to DNA damage

    PubMed Central

    Maure, Jean-François; Moser, Sandra C.; Jaffray, Ellis G.; F. Alpi, Arno; Hay, Ronald T.

    2016-01-01

    SUMO and ubiquitin play important roles in the response of cells to DNA damage. These pathways are linked by the SUMO Targeted ubiquitin Ligase Rnf4 that catalyses transfer of ubiquitin from a ubiquitin loaded E2 conjugating enzyme to a polySUMO modified substrate. Rnf4 can functionally interact with multiple E2s, including Ube2w, in vitro. Chicken cells lacking Rnf4 are hypersensitive to hyroxyurea, DNA alkylating drugs and DNA crosslinking agents, but this sensitivity is suppressed by simultaneous depletion of Ube2w. Cells depleted of Ube2w alone are not hypersensitive to the same DNA damaging agents. Similar results were also obtained in human cells. These data indicate that Ube2w does not have an essential role in the DNA damage response, but is deleterious in the absence of Rnf4. Thus, although Rnf4 and Ube2w functionally interact in vitro, our genetic experiments indicate that in response to DNA damage Ube2w and Rnf4 function in distinct pathways. PMID:27185577

  19. Intact subepidermal nerve fibers mediate mechanical hypersensitivity via the activation of protein kinase C gamma in spared nerve injury

    PubMed Central

    Ko, Miau-Hwa; Yang, Ming-Ling; Youn, Su-Chung; Tseng, To-Jung

    2016-01-01

    Background Spared nerve injury is an important neuropathic pain model for investigating the role of intact primary afferents in the skin on pain hypersensitivity. However, potential cellular mechanisms remain poorly understood. In phosphoinositide-3 kinase pathway, pyruvate dehydrogenase kinase 1 (PDK1) participates in the regulation of neuronal plasticity for central sensitization. The downstream cascades of PDK1 include: (1) protein kinase C gamma (PKCγ) controls the trafficking and phosphorylation of ionotropic glutamate receptor; (2) protein kinase B (Akt)/the mammalian target of rapamycin (mTOR) signaling is responsible for local protein synthesis. Under these statements, we therefore hypothesized that an increase of PKCγ activation and mTOR-dependent PKCγ synthesis in intact primary afferents after SNI might contribute to pain hypersensitivity. Results The variants of spared nerve injury were performed in Sprague-Dawley rats by transecting any two of the three branches of the sciatic nerve, leaving only one branch intact. Following SNIt (spared tibial branch), mechanical hyperalgesia and mechanical allodynia, but not thermal hyperalgesia, were significantly induced. In the first footpad, normal epidermal innervations were verified by the protein gene product 9.5 (PGP9.5)- and growth-associated protein 43 (GAP43)-immunoreactive (IR) intraepidermal nerve fibers (IENFs) densities. Furthermore, the rapid increases of phospho-PKCγ- and phospho-mTOR-IR subepidermal nerve fibers (SENFs) areas were distinct gathered from the results of PGP9.5-, GAP43-, and neurofilament 200 (NF200)-IR SENFs areas. The efficacy of PKC inhibitor (GF 109203X) or mTOR complex 1 inhibitor (rapamycin) for attenuating mechanical hyperalgesia and mechanical allodynia by intraplantar injection was dose-dependent. Conclusions From results obtained in this study, we strongly recommend that the intact SENFs persistently increase PKCγ activation and mTOR-dependent PKCγ synthesis participate

  20. Pharmacogenetics of drug hypersensitivity

    PubMed Central

    Phillips, Elizabeth J; Mallal, Simon A

    2010-01-01

    Drug hypersensitivity reactions and severe cutaneous adverse drug reactions, such as Stevens–Johnson syndrome and toxic epidermal necrolysis, are examples of serious adverse drug reactions mediated through a combination of metabolic and immunological mechanisms that could traditionally not have been predicted based on the pharmacological characteristics of the drug alone. The discovery of new associations between these syndromes and specific HLA has created the promise that risk for these reactions could be predicted through pharmacogenetic screening, thereby avoiding serious morbidity and mortality associated with these types of drug reactions. Despite this, several hurdles exist in the translation of these associations into pharmacogenetic tests that could be routinely used in the clinical setting. HLA-B*5701 screening to prevent abacavir hypersensitivity syndrome is an example of a test now in widespread routine clinical use in the developed world. PMID:20602616

  1. Pharmacogenetic determinants of immediate and delayed reactions of drug hypersensitivity.

    PubMed

    Guéant, J L; Guéant-Rodriguez, R M; Gastin, I Aimone; Cornejo-García, J A; Viola, M; Barbaud, A; Mertes, P M; Blanca, M; Romano, A

    2008-01-01

    Drug allergy refers to a hypersensitivity reaction for which either an IgE or T-cell-mediated mechanism is demonstrated. The recognition of the drug by B and T cells is influenced by variants of HLA genes. The genetic factors involved in IgE-mediated mechanisms have been studied mainly in beta-lactam reactions, and they appear to be related to human leukocyte antigen presentation (HLA A2 and DRw52), TNFA -308G>A, class switching to IgE by B cells (variants of IL-13 and of IL-4RA), and expression of IgE receptors on target cells (variant of the FcepsilonRIbeta gene). Delayed T-cell-mediated reactions are also associated with HLA alleles. Studies have reported an association of HLA-B*1502 and HLA-B*5801 in patients with the Stevens-Johnson syndrome or toxic epidermal necrolysis provoked by carbamazepine, as well as of HLA-B*5701 with abacavir hypersensitivity. HLA-B*5701 seems to be a strong predictor in whites, but not in Hispanics or Africans. Carbamazepine hypersensitivity is also influenced by gene variants of cytochrome P450 enzymes on the generation of reactive metabolites, while CYP2C9*2 and CYP2C9*3 polymorphisms influence the bioactivation of sulfamethoxazole in prohapten. Pharmacogenetic studies on aspirin hypersensitivity have identified distinct types of predictors, such as HLA genotypes, a polymorphism in the promoter of the FcepsilonRIalpha gene, and variants in genes of enzymes from the arachidonic acid pathway. In the future, identification of genetic predictors will benefit from genomewide association studies that also take ethnic differences into account. Ideally, predictors will help to prevent adverse reactions, as suggested by a recent study on the effectiveness of prospective HLA-B*5701 screening to prevent hypersensitivity reactions to abacavir in HIV patients. PMID:18991696

  2. Ablation of type I hypersensitivity in experimental allergic conjunctivitis by eotaxin-1/CCR3 blockade

    PubMed Central

    Nakamura, Takao; Ohbayashi, Masaharu; Kuo, Chuan Hui; Komatsu, Naoki; Yakura, Keiko; Tominaga, Takeshi; Inoue, Yoshitsugu; Higashi, Hidemitsu; Murata, Meguru; Takeda, Shuzo; Fukushima, Atsuki; Liu, Fu-Tong; Rothenberg, Marc E.; Ono, Santa Jeremy

    2009-01-01

    The immune response is regulated, in part, by effector cells whose activation requires multiple signals. For example, T cells require signals emanating from the T cell antigen receptor and co-stimulatory molecules for full activation. Here, we present evidence indicating that IgE-mediated hypersensitivity reactions in vivo also require cognate signals to activate mast cells. Immediate hypersensitivity reactions in the conjunctiva are ablated in mice deficient in eotaxin-1, despite normal numbers of tissue mast cells and levels of IgE. To further define the co-stimulatory signals mediated by chemokine receptor 3 (CCR3), an eotaxin-1 receptor, effects of CCR3 blockade were tested with an allergic conjunctivitis model and in ex vivo isolated connective tissue-type mast cells. Our results show that CCR3 blockade significantly suppresses allergen-mediated hypersensitivity reactions as well as IgE-mediated mast cell degranulation. We propose that a co-stimulatory axis by CCR3, mainly stimulated by eotaxin-1, is pivotal in mast cell-mediated hypersensitivity reactions. PMID:19147836

  3. Delayed drug hypersensitivity reactions - new concepts.

    PubMed

    Posadas, S J; Pichler, W J

    2007-07-01

    Immune reactions to small molecular compounds such as drugs can cause a variety of diseases mainly involving skin, but also liver, kidney, lungs and other organs. In addition to the well-known immediate, IgE-mediated reactions to drugs, many drug-induced hypersensitivity reactions appear delayed. Recent data have shown that in these delayed reactions drug-specific CD4(+) and CD8(+) T cells recognize drugs through their T cell receptors (TCR) in an MHC-dependent way. Immunohistochemical and functional studies of drug-reactive T cells in patients with distinct forms of exanthems revealed that distinct T cell functions lead to different clinical phenotypes. Taken together, these data allow delayed hypersensitivity reactions (type IV) to be further subclassified into T cell reactions, which by releasing certain cytokines and chemokines preferentially activate and recruit monocytes (type IVa), eosinophils (type IVb), or neutrophils (type IVd). Moreover, cytotoxic functions by either CD4(+) or CD8(+) T cells (type IVc) seem to participate in all type IV reactions. Drugs are not only immunogenic because of their chemical reactivity, but also because they may bind in a labile way to available TCRs and possibly MHC-molecules. This seems to be sufficient to stimulate certain, probably preactivated T cells. The drug seems to bind first to the fitting TCR, which already exerts some activation. For full activation, an additional interaction of the TCR with the MHC molecules is needed. The drug binding to the receptor structures is reminiscent of a pharmacological interaction between a drug and its (immune) receptor and was thus termed the p-i concept. In some patients with drug hypersensitivity, such a response occurs within hours even upon the first exposure to the drug. The T cell reaction to the drug might thus not be due to a classical, primary response, but is due to peptide-specific T cells which happen to be stimulated by a drug. This new concept has major implications

  4. Osteopontin Is Involved in the Initiation of Cutaneous Contact Hypersensitivity by Inducing Langerhans and Dendritic Cell Migration to Lymph Nodes

    PubMed Central

    Weiss, J.M.; Renkl, A.C.; Maier, C.S.; Kimmig, M.; Liaw, L.; Ahrens, T.; Kon, S.; Maeda, M.; Hotta, H.; Uede, T.; Simon, J.C.

    2001-01-01

    Osteopontin (OPN) is a chemotactic protein that attracts immune cells, to inflammatory sites. The sensitization phase of allergic cutaneous contact hypersensitivity (CHS) requires the migration of Langerhans cells/dendritic cells (LCs/DCs) from skin to draining lymph nodes. Characterizing OPN function for LC/DC migration we found upregulated OPN expression in hapten sensitized skin and draining lymph nodes. OPN induces chemotactic LC/DC migration, initiates their emigration from the epidermis, and attracts LCs/DCs to draining lymph nodes by interacting with CD44 and αv integrin. Furthermore, OPN-deficient mice have a significantly reduced CHS response that correlates with an impaired ability of OPN-deficient mice to attract LCs/DCs to draining lymph nodes. In conclusion, OPN is an important factor in the initiation of CHS by guiding LCs/DCs from skin into lymphatic organs. PMID:11696588

  5. [Food hypersensitivity in children].

    PubMed

    Kolacek, Sanja

    2011-01-01

    Food hypersensitivity affects children and adults with an increasing prevalence, and is therefore an important public health problem in the majority of developed countries. Moreover, self-reported reactions to food are of several times higher prevalence, compared to hypersensitivity diagnosed following well established evidence-based diagnostic guidelines. In children, allergic food reactions are more common compared to non-allergic food hypersensitivity reactions, and 90% of them are caused with only 8 food allergens: cow's milk, soya, egg, fish, shellfish, peanut, tree-nuts and gluten. Diagnosis should be based on challenge tests with the potentially offending food allergens. Concerning other, more conservative diagnostic procedures, negative serology and negative skin-prick tests can exclude IgE-mediated food allergy, but positive tests, due to high rate of false positive reactions are not sufficient for diagnosis. Strict dietary avoidance of incriminated allergens is the only well established management strategy. However, this should be applied only if food allergy is well documented - following the exposition tests. Introducing elimination diet in a paediatric population, particularly with the elimination of multiple foods, could cause inappropriate growth and disturb organ maturation. Concerning allergy prevention, avoidance of allergens is not efficacious either during pregnancy and lactation or weaning period, and is therefore, not recommended neither as a population preventive measure, nor in children at risk.

  6. Pepper suppressor of the G2 allele of skp1 interacts with the receptor-like cytoplasmic kinase1 and type III effector AvrBsT and promotes the hypersensitive cell death response in a phosphorylation-dependent manner.

    PubMed

    Kim, Nak Hyun; Kim, Dae Sung; Chung, Eui Hwan; Hwang, Byung Kook

    2014-05-01

    Xanthomonas campestris pv vesicatoria type III effector protein, AvrBsT, triggers hypersensitive cell death in pepper (Capsicum annuum). Here, we have identified the pepper SGT1 (for suppressor of the G2 allele of skp1) as a host interactor of AvrBsT and also the pepper PIK1 (for receptor-like cytoplasmic kinase1). PIK1 specifically phosphorylates SGT1 and AvrBsT in vitro. AvrBsT specifically binds to the CHORD-containing protein and SGT1 domain of SGT1, resulting in the inhibition of PIK1-mediated SGT1 phosphorylation and subsequent nuclear transport of the SGT1-PIK1 complex. Liquid chromatography-tandem mass spectrometry of the proteolytic peptides of SGT1 identified the residues serine-98 and serine-279 of SGT1 as the major PIK1-mediated phosphorylation sites. Site-directed mutagenesis of SGT1 revealed that the identified SGT1 phosphorylation sites are responsible for the activation of AvrBsT-triggered cell death in planta. SGT1 forms a heterotrimeric complex with both AvrBsT and PIK1 exclusively in the cytoplasm. Agrobacterium tumefaciens-mediated coexpression of SGT1 and PIK1 with avrBsT promotes avrBsT-triggered cell death in Nicotiana benthamiana, dependent on PIK1. Virus-induced silencing of SGT1 and/or PIK1 compromises avrBsT-triggered cell death, hydrogen peroxide production, defense gene induction, and salicylic acid accumulation, leading to the enhanced bacterial pathogen growth in pepper. Together, these results suggest that SGT1 interacts with PIK1 and the bacterial effector protein AvrBsT and promotes the hypersensitive cell death associated with PIK1-mediated phosphorylation in plants.

  7. Hypersensitivity to antineoplastic agents.

    PubMed

    Castells, M C

    2008-01-01

    The need to offer first line therapy for primary and recurrent cancers has spurred the clinical development of rapid desensitizations for chemotherapy and monoclonal antibodies. Rapid desensitizations allow patients to be treated with medications to which they have presented with hypersensitivity reactions (HSRs), including anaphylaxis. Rapid desensitization achieves temporary tolerization to full therapeutic doses by slow administration of incremental doses of the drug inducing the HSR. Protocols are available for most chemotherapy agents, including taxanes, platins, doxorubicin, monoclonal antibodies, and others. Candidate patients include those who present with type I HSRs, mast cell/IgE dependent, including anaphylaxis, and non-IgE mediated HSRs, during the chemotherapy infusion or shortly after. Idiosyncratic reactions, erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis are not amenable to rapid desensitization. The recommendation for rapid desensitization can only be made by allergy and immunology specialists and can only be performed in settings with one-to-one nurse-patient care and where resuscitation personnel and resources are readily available. Repeated desensitizations can be safely performed in outpatient settings with similar conditions, which allow cancer patients to remain in clinical studies. We have generated a universal 12-step protocol that was applied to 413 cases of intravenous and intraperitoneal rapid desensitizations using taxanes, platins, liposomal doxorubicin, doxorubicin, rituximab, and other chemotherapy drugs. Under this protocol all patients were able to complete their target dose, and 94% of the patients had limited or no reactions. No deaths or codes were reported, indicating that the procedure was safe and effective in delivering first line chemotherapy drugs. PMID:18991707

  8. The chemical mediation of delayed hypersensitivity skin reactions. I. Purification of a macrophage-chemotactic factor from bovien gamma-globulin-induced skin reactions in guinea pigs.

    PubMed Central

    Kambara, T.; Ueda, K.; Maeda, S.

    1977-01-01

    A macrophage-chemotactic factor (MCFS) was extracted in the pseudoglobulin fraction from delayed hypersensitivity skin lesions induced by bovine gamma-globulin in guinea pigs. Its chemotactic activity was estimated by a modification of Boyden's method using Nuclepore filter. After chromatography of the protein fraction using Sephadex G-50 and DEAE-cellulose, in that order, two chemotactic fractions were obtained. The chemotactic factor with stronger activity (MCFS-1) was further highly purified (488-fold) by chromatography on CM-Sephadex. This factor migrated in a single band on acrylamide disc gel electrophoresis and was found to be a protein that was free of nucleic acid. Gel filtration showed that its molecular weight was similar to that of IgG. Its chemotactic activity was heat labile. Intradermal injection of this factor into normal guinea pigs induced a pronounced mononuclear cell emigration from venules. These findings are pertinent to understanding macrophage reaction in the delayed hypersensitivity reactions. Am J Pathol 87:359-374, 1977). Images Figure 1 Figure 2 Figure 3 PMID:66878

  9. A single gene, AIN, in Medicago truncatula mediates a hypersensitive response to both bluegreen aphid and pea aphid, but confers resistance only to bluegreen aphid.

    PubMed

    Klingler, John P; Nair, Ramakrishnan M; Edwards, Owain R; Singh, Karam B

    2009-01-01

    Biotic stress in plants frequently induces a hypersensitive response (HR). This distinctive reaction has been studied intensively in several pathosystems and has shed light on the biology of defence signalling. Compared with microbial pathogens, relatively little is known about the role of the HR in defence against insects. Reference genotype A17 of Medicago truncatula Gaertn., a model legume, responds to aphids of the genus Acyrthosiphon with necrotic lesions resembling a HR. In this study, the biochemical nature of this response, its mode of inheritance, and its relationship with defence against aphids were investigated. The necrotic lesion phenotype and resistance to the bluegreen aphid (BGA, Acyrthosiphon kondoi Shinji) and the pea aphid (PA, Acyrthosiphon pisum (Harris)) were analysed using reference genotypes A17 and A20, their F(2) progeny and recombinant inbred lines. BGA-induced necrotic lesions co-localized with the production of H(2)O(2), consistent with an oxidative burst widely associated with hypersensitivity. This HR correlated with stronger resistance to BGA in A17 than in A20; these phenotypes cosegregated as a semi-dominant gene, AIN (Acyrthosiphon-induced necrosis). In contrast to BGA, stronger resistance to PA in A17, compared with A20, did not cosegregate with a PA-induced HR. The AIN locus resides in a cluster of sequences predicted to encode the CC-NBS-LRR subfamily of resistance proteins. AIN-mediated resistance presents a novel opportunity to use a model plant and model aphid to study the role of the HR in defence responses to phloem-feeding insects. PMID:19690018

  10. Cell-Mediated Drugs Delivery

    PubMed Central

    Batrakova, Elena V.; Gendelman, Howard E.; Kabanov, Alexander V.

    2011-01-01

    INTRODUCTION Drug targeting to sites of tissue injury, tumor or infection with limited toxicity is the goal for successful pharmaceutics. Immunocytes (including mononuclear phagocytes (dendritic cells, monocytes and macrophages), neutrophils, and lymphocytes) are highly mobile; they can migrate across impermeable barriers and release their drug cargo at sites of infection or tissue injury. Thus immune cells can be exploited as trojan horses for drug delivery. AREAS COVERED IN THIS REVIEW This paper reviews how immunocytes laden with drugs can cross the blood brain or blood tumor barriers, to facilitate treatments for infectious diseases, injury, cancer, or inflammatory diseases. The promises and perils of cell-mediated drug delivery are reviewed, with examples of how immunocytes can be harnessed to improve therapeutic end points. EXPERT OPINION Using cells as delivery vehicles enables targeted drug transport, and prolonged circulation times, along with reductions in cell and tissue toxicities. Such systems for drug carriage and targeted release represent a novel disease combating strategy being applied to a spectrum of human disorders. The design of nanocarriers for cell-mediated drug delivery may differ from those used for conventional drug delivery systems; nevertheless, engaging different defense mechanisms into drug delivery may open new perspectives for the active delivery of drugs. PMID:21348773

  11. Chemokine-dependent T cell migration requires aquaporin-3–mediated hydrogen peroxide uptake

    PubMed Central

    Chikuma, Shunsuke; Sugiyama, Yoshinori; Kabashima, Kenji; Verkman, Alan S.; Inoue, Shintaro; Miyachi, Yoshiki

    2012-01-01

    Chemokine-dependent trafficking is indispensable for the effector function of antigen-experienced T cells during immune responses. In this study, we report that the water/glycerol channel aquaporin-3 (AQP3) is expressed on T cells and regulates their trafficking in cutaneous immune reactions. T cell migration toward chemokines is dependent on AQP3-mediated hydrogen peroxide (H2O2) uptake but not the canonical water/glycerol transport. AQP3-mediated H2O2 transport is essential for the activation of the Rho family GTPase Cdc42 and the subsequent actin dynamics. Coincidentally, AQP3-deficient mice are defective in the development of hapten-induced contact hypersensitivity, which is attributed to the impaired trafficking of antigen-primed T cells to the hapten-challenged skin. We therefore suggest that AQP3-mediated H2O2 uptake is required for chemokine-dependent T cell migration in sufficient immune response. PMID:22927550

  12. The Rab GTPase RabG3b positively regulates autophagy and immunity-associated hypersensitive cell death in Arabidopsis.

    PubMed

    Kwon, Soon Il; Cho, Hong Joo; Kim, Sung Ryul; Park, Ohkmae K

    2013-04-01

    A central component of the plant defense response to pathogens is the hypersensitive response (HR), a form of programmed cell death (PCD). Rapid and localized induction of HR PCD ensures that pathogen invasion is prevented. Autophagy has been implicated in the regulation of HR cell death, but the functional relationship between autophagy and HR PCD and the regulation of these processes during the plant immune response remain controversial. Here, we show that a small GTP-binding protein, RabG3b, plays a positive role in autophagy and promotes HR cell death in response to avirulent bacterial pathogens in Arabidopsis (Arabidopsis thaliana). Transgenic plants overexpressing a constitutively active RabG3b (RabG3bCA) displayed accelerated, unrestricted HR PCD within 1 d of infection, in contrast to the autophagy-defective atg5-1 mutant, which gradually developed chlorotic cell death through uninfected sites over several days. Microscopic analyses showed the accumulation of autophagic structures during HR cell death in RabG3bCA cells. Our results suggest that RabG3b contributes to HR cell death via the activation of autophagy, which plays a positive role in plant immunity-triggered HR PCD.

  13. Phospholipase D-mediated hypersensitivity at central synapses is associated with abnormal behaviours and pain sensitivity in rats exposed to prenatal stress.

    PubMed

    Sun, Liting; Gooding, Hayley L; Brunton, Paula J; Russell, John A; Mitchell, Rory; Fleetwood-Walker, Sue

    2013-11-01

    Adverse events at critical stages of development can lead to lasting dysfunction in the central nervous system (CNS). To seek potential underlying changes in synaptic function, we used a newly developed protocol to measure alterations in receptor-mediated Ca(2+) fluorescence responses of synaptoneurosomes, freshly isolated from selected regions of the CNS concerned with emotionality and pain processing. We compared adult male controls and offspring of rats exposed to social stress in late pregnancy (prenatal stress, PS), which showed programmed behavioural changes indicating anxiety, anhedonia and pain hypersensitivity. We found corresponding increases, in PS rats compared with normal controls, in responsiveness of synaptoneurosomes from frontal cortex to a glutamate receptor (GluR) agonist, and from spinal cord to activators of nociceptive afferents. Through a combined pharmacological and biochemical strategy, we found evidence for a role of phospholipase D1 (PLD1)-mediated signalling, that may involve 5-HT2A receptor (5-HT2AR) activation, at both levels of the nervous system. These changes might participate in underpinning the enduring alterations in behaviour induced by PS. PMID:23932932

  14. Avocado hypersensitivity.

    PubMed

    Blanco, C; Carrillo, T; Castillo, R; Quiralte, J; Cuevas, M

    1994-07-01

    The avocado (Av) is a fruit that belongs to the Lauraceae family. We report 17 patients with immediate hypersensitivity to avocado. Clinical manifestations in relation to avocado ingestion were as follows: systemic anaphylaxis in seven patients, angioedema/urticaria in six, vomiting in two, bronchial asthma in one, and rhinoconjunctivitis in one. Skin prick test (SPT) with fresh avocado was positive in all patients with the Strong avocado variety (SAv) and in 14 patients with the Hass avocado variety (HAv). Our patient-associated sensitizations were as follows: 10 to latex, eight to chestnut, eight to banana, four to kiwi, and four to walnut. Avocado-sensitized patients with latex allergy were typically middle-aged women, professionally exposed to latex, who also exhibited frequent associated sensitizations to chestnut, banana, and other fruits. Specific IgE against avocado was demonstrated in 11 of our patients, by both commercial CAP and RAST with avocado extract coupled to nitrocellulose disks. Despite its lower protein content, SAv seems to be more allergenic than HAv, both in vivo and in vitro. On incubating a pool of sera from our patients with avocado, latex, chestnut, and banana extracts, a progressive RAST inhibition was obtained, with SAv- and chestnut-marked disks. This suggests the existence of common antigenic determinants among these allergens.

  15. Absence of cross-reactivity to carbapenems in patients with delayed hypersensitivity to penicillins.

    PubMed

    Romano, A; Gaeta, F; Valluzzi, R L; Alonzi, C; Maggioletti, M; Zaffiro, A; Caruso, C; Quaratino, D

    2013-12-01

    Studies performed on subjects with IgE-mediated hypersensitivity to penicillins have demonstrated a 1% rate of cross-reactivity between penicillins and both imipenem and meropenem, while a single study found a 5.5% rate of cross-reactivity with imipenem/cilastatin in subjects with T-cell-mediated hypersensitivity to β-lactams, mostly penicillins. We studied 204 consecutive subjects with a well-demonstrated T-cell-mediated hypersensitivity to assess the cross-reactivity with carbapenems and the tolerability of such alternative β-lactams. All 204 subjects underwent skin tests with imipenem/cilastatin and meropenem; 130 of them were skin-tested also with ertapenem. Subjects with negative test results were challenged with these carbapenems. All subjects displayed negative skin tests to carbapenems and tolerated challenges. These data demonstrate the absence of clinically significant T-cell-mediated cross-reactivity between penicillins and carbapenems. Negative delayed-reading skin testing with carbapenems in individuals with documented T-cell-mediated hypersensitivity to penicillins correlates well with subsequent clinical tolerance of therapeutic doses of carbapenems.

  16. The Effect of Docetaxel (Taxotere®) on Human Gastric Cancer Cells Exhibiting Low-Dose Radiation Hypersensitivity

    PubMed Central

    Balcer-Kubiczek, Elizabeth K.; Attarpour, Mona; Wang, Jian Z.; Regine, William F.

    2008-01-01

    Low-dose radiation hypersensitivity (HRS) describes a phenomenon of excessive sensitivity to X ray doses <0.5 Gy. Docetaxel is a taxane shown to arrest cells in the G2/M phase of the cell cycle. Some previous studies suggested that HRS might result from the abrogation of the early G2 checkpoint arrest. First we tested whether HRS occurs in gastric cancer—derived cells, and whether pre-treatment of cells with low docetaxel concentrations can enhance the magnitude of HRS in gastric cancer cells. The results demonstrated HRS at ~0.3 Gy and the synergy between 0.3 Gy and docetaxel (3 nM for 24 h), and the additivity of other drug/dose combinations. The synergistic effect was associated with a significant docetaxel-induced G2 accumulation. Next, we evaluated in time-course experiments ATM kinase activity and proteins associated with the induction and maintenance of the early G2 checkpoint. The results of multi-immunoblot analysis demonstrate that HRS does not correlate with the ATM-dependent early G2 checkpoint arrest. We speculate that G2 checkpoint adaptation, a phenomenon associated with a prolonged cell cycle arrest, might be involved in HRS. Our results also suggest a new approach for the improvement the effectiveness of docetaxel-based radiotherapy using low doses per fraction. PMID:21892291

  17. Maternal and postnatal dietary probiotic supplementation enhances splenic regulatory T helper cell population and reduces peanut allergen-induced hypersensitivity responses in mice.

    PubMed

    Toomer, Ondulla T; Ferguson, Martine; Pereira, Marion; Do, Andrew; Bigley, Elmer; Gaines, Dennis; Williams, Kristina

    2014-09-01

    Neonatal to early childhood is the critical period for establishing a balance of T helper 1 (Th1) versus T helper 2 (Th2) cellular immunity within the gut, which is strongly influenced by the source and establishment of gut microflora. Probiotic administration has been shown to attenuate Th2-biased cellular immunity and predisposition to food allergies. To test this hypothesis we provided ad libitum a probiotic-supplemented (Primalac 454 Feed Grade Microbials) or control diet to lactating dams with suckling pups and weaned pups until 10 weeks of age. Weaned mice were sensitized/challenged with peanut extract, saline or adjuvant at 6, 8 and 10 weeks of age. At 3, 6, 8 and 10 weeks, fecal samples were collected for microbial analysis, while blood samples were analyzed for total plasma IgE levels. At termination (10 weeks of age), splenic T lymphocyte population subtypes were determined using FACS analysis and Th1/Th2/Th17 gene expression by PCR array. Mice given the probiotic-supplemented diet had significantly enhanced probiotic fecal counts compared to controls at 3, 6, 8 and 10 weeks. Moreover, mice fed the probiotic-supplemented diet had enhanced splenic naturally occurring T regulatory cell populations, and reduced splenic gene expression of allergic mediator IL-13 compared to controls. These results provide evidence that early probiotic supplementation may provide host protection to hypersensitivity reactions to food allergens by attenuating food allergen inflammatory responses.

  18. Transcriptional activation of human adult alpha-globin genes by hypersensitive site-40 enhancer: function of nuclear factor-binding motifs occupied in erythroid cells.

    PubMed Central

    Rombel, I; Hu, K Y; Zhang, Q; Papayannopoulou, T; Stamatoyannopoulos, G; Shen, C K

    1995-01-01

    The developmental stage- and erythroid lineage-specific activation of the human embryonic zeta- and fetal/adult alpha-globin genes is controlled by an upstream regulatory element [hypersensitive site (HS)-40] with locus control region properties, a process mediated by multiple nuclear factor-DNA complexes. In vitro DNase I protection experiments of the two G+C-rich, adult alpha-globin promoters have revealed a number of binding sites for nuclear factors that are common to HeLa and K-562 extracts. However, genomic footprinting analysis has demonstrated that only a subset of these sites, clustered between -130 and +1, is occupied in an erythroid tissue-specific manner. The function of these in vivo-occupied motifs of the alpha-globin promoters, as well as those previously mapped in the HS-40 region, is assayed by site-directed mutagenesis and transient expression in embryonic/fetal erythroid K-562 cells. These studies, together with our expression data on the human embryonic zeta-globin promoter, provide a comprehensive view of the functional roles of individual nuclear factor-DNA complexes in the final stages of transcriptional activation of the human alpha-like globin promoters by the HS-40 element. Images Fig. 2 Fig. 3 Fig. 5 Fig. 6 PMID:7604012

  19. Comprehensive transcriptional and functional analyses of melatonin synthesis genes in cassava reveal their novel role in hypersensitive-like cell death

    PubMed Central

    Wei, Yunxie; Hu, Wei; Wang, Qiannan; Liu, Wei; Wu, Chunjie; Zeng, Hongqiu; Yan, Yu; Li, Xiaolin; He, Chaozu; Shi, Haitao

    2016-01-01

    Melatonin is a widely known hormone in animals. Since melatonin was discovered in plants, more and more studies highlight its involvement in a wide range of physiological processes including plant development and stress responses. Many advances have been made in the terms of melatonin-mediated abiotic stress resistance and innate immunity in plants, focusing on model plants such as rice and Arabidopsis. In this study, 7 melatonin synthesis genes were systematically analyzed in cassava. Quantitative real-time PCR showed that all these genes were commonly regulated by melatonin, flg22, Xanthomonas axonopodis pv manihotis (Xam) and hydrogen peroxide (H2O2). Transient expression in Nicotiana benthamiana revealed the subcellular locations and possible roles of these melatonin synthesis genes. Notably, we highlight novel roles of these genes in hypersensitive-like cell death, as confirmed by the results of several physiological parameters. Moreover, transient expression of these genes had significant effects on the transcripts of reactive oxygen species (ROS) accumulation and defense-related genes, and triggered the burst of callose depositions and papillae-associated plant defense, indicating the possible role of them in plant innate immunity. Taken together, this study reveals the comprehensive transcripts and putative roles of melatonin synthesis genes as well as melatonin in immune responses in cassava. PMID:27739451

  20. Cell-mediated immune responses in owl monkeys (Aotus trivirgatus) with trachoma to soluble antigens of Chlamydia trachomatis.

    PubMed Central

    Sacks, D L; Todd, W J; Macdonald, A B

    1978-01-01

    The first temporal study of the cell-mediated immune responses (CMI) following ocular infections with Chlamydia trachomatis is presented. We examined the CMI of owl monkeys infected with trachoma to soluble antigens of C. trachomatis by leucocyte migration inhibition (LIF) and delayed hypersensitivity skin testing. Delayed hypersensitivity of a systemic nature developed after a local eye infection in owl monkeys; clearance of inclusions from conjunctival cells coincided with the onset of this response. The association of eye secretion and circulating antibodies with recovery from primary infection was not so striking. Both cellular and humoral immune responses persisted for at least 2 months, at which time all test animals were completely resistant to re-infection. The elicitation of cell-mediated immune reactions with solubilized chlamydial antigens may permit the isolation of specific antigens involved in the generation of protective immunity in the owl monkey model. PMID:101327

  1. Ectopically expressed sweet pepper ferredoxin PFLP enhances disease resistance to Pectobacterium carotovorum subsp. carotovorum affected by harpin and protease-mediated hypersensitive response in Arabidopsis.

    PubMed

    Ger, Mang-Jye; Louh, Guan-Yu; Lin, Yi-Hsien; Feng, Teng-Yung; Huang, Hsiang-En

    2014-12-01

    Plant ferredoxin-like protein (PFLP) is a photosynthesis-type ferredoxin (Fd) found in sweet pepper. It contains an iron-sulphur cluster that receives and delivers electrons between enzymes involved in many fundamental metabolic processes. It has been demonstrated that transgenic plants overexpressing PFLP show a high resistance to many bacterial pathogens, although the mechanism remains unclear. In this investigation, the PFLP gene was transferred into Arabidopsis and its defective derivatives, such as npr1 (nonexpresser of pathogenesis-related gene 1) and eds1 (enhanced disease susceptibility 1) mutants and NAHG-transgenic plants. These transgenic plants were then infected with the soft-rot bacterial pathogen Pectobacterium carotovorum subsp. carotovorum (Erwinia carotovora ssp. carotovora, ECC) to investigate the mechanism behind PFLP-mediated resistance. The results revealed that, instead of showing soft-rot symptoms, ECC activated hypersensitive response (HR)-associated events, such as the accumulation of hydrogen peroxide (H2 O2 ), electrical conductivity leakage and expression of the HR marker genes (ATHSR2 and ATHSR3) in PFLP-transgenic Arabidopsis. This PFLP-mediated resistance could be abolished by inhibitors, such as diphenylene iodonium (DPI), 1-l-trans-epoxysuccinyl-leucylamido-(4-guanidino)-butane (E64) and benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk), but not by myriocin and fumonisin. The PFLP-transgenic plants were resistant to ECC, but not to its harpin mutant strain ECCAC5082. In the npr1 mutant and NAHG-transgenic Arabidopsis, but not in the eds1 mutant, overexpression of the PFLP gene increased resistance to ECC. Based on these results, we suggest that transgenic Arabidopsis contains high levels of ectopic PFLP; this may lead to the recognition of the harpin and to the activation of the HR and other resistance mechanisms, and is dependent on the protease-mediated pathway.

  2. Mast cells mediate the immune suppression induced by dermal exposure to JP-8 jet fuel.

    PubMed

    Limón-Flores, Alberto Y; Chacón-Salinas, Rommel; Ramos, Gerardo; Ullrich, Stephen E

    2009-11-01

    Applying jet propulsion-8 (JP-8) jet fuel to the skin of mice induces immune suppression. Applying JP-8 to the skin of mice suppresses T-cell-mediated immune reactions including, contact hypersensitivity (CHS) delayed-type hypersensitivity and T-cell proliferation. Because dermal mast cells play an important immune regulatory role in vivo, we tested the hypothesis that mast cells mediate jet fuel-induced immune suppression. When we applied JP-8 to the skin of mast cell deficient mice CHS was not suppressed. Reconstituting mast cell deficient mice with wild-type bone marrow derived mast cells (mast cell "knock-in mice") restored JP-8-induced immune suppression. When, however, mast cells from prostaglandin E(2) (PGE(2))-deficient mice were used, the ability of JP-8 to suppress CHS was not restored, indicating that mast cell-derived PGE(2) was activating immune suppression. Examining the density of mast cells in the skin and lymph nodes of JP-8-treated mice indicated that jet fuel treatment caused an initial increase in mast cell density in the skin, followed by increased numbers of mast cells in the subcutaneous space and then in draining lymph nodes. Applying JP-8 to the skin increased mast cell expression of CXCR4, and increased the expression of CXCL12 by draining lymph node cells. Because CXCL12 is a chemoattractant for CXCR4+ mast cells, we treated JP-8-treated mice with AMD3100, a CXCR4 antagonist. AMD3100 blocked the mobilization of mast cells to the draining lymph node and inhibited JP-8-induced immune suppression. Our findings demonstrate the importance of mast cells in mediating jet fuel-induced immune suppression.

  3. Glucocorticoid receptor-dependent inhibition of cellular proliferation in dexamethasone-resistant and hypersensitive rat hepatoma cell variants.

    PubMed Central

    Cook, P W; Swanson, K T; Edwards, C P; Firestone, G L

    1988-01-01

    Exposure of the Fu5 rat hepatoma cell line to glucocorticoids, such as dexamethasone and hydrocortisone, suppressed the growth rate and final density of cells grown in the presence of serum. This hormonal effect was proportional to receptor occupancy and affinity and, in addition, the glucocorticoid antagonist RU38486 prevented this response. Two classes of dexamethasone-resistant variants that failed to be growth inhibited were recovered from ethyl methylsulfonate-mutagenized populations by continuous culture in the presence of 1 microM dexamethasone. The first class, represented by the EDR3 subclone, was completely glucocorticoid unresponsive and failed to express receptor transcripts. The second class, represented by the EDR1, EDR5, and EDR7 subclones, possessed significant levels of glucocorticoid receptor but were only partially glucocorticoid responsive when stimulated with saturating levels of hormone. Introduction of functional glucocorticoid receptor genes into both classes of dexamethasone-resistant variants by a recombinant retrovirus expression vector restored glucocorticoid responsiveness and suppression of cell growth. A hypersensitive variant (BDS1), recovered by bromodeoxyuridine selection, was fully glucocorticoid responsive, and its inhibition of proliferation was more acutely regulated by dexamethasone. Taken together, our results established that the inhibition of proliferation in Fu5 rat hepatoma cells represents a new glucocorticoid response that requires the expression of a functional glucocorticoid receptor. Images PMID:3380086

  4. Delayed drug hypersensitivity reactions.

    PubMed

    Pichler, Werner J

    2003-10-21

    Immune reactions to small molecular compounds, such as drugs, can cause a variety of diseases involving the skin, liver, kidney, and lungs. In many drug hypersensitivity reactions, drug-specific CD4+ and CD8+ T cells recognize drugs through their alphabeta T-cell receptors in an MHC-dependent way. Drugs stimulate T cells if they act as haptens and bind covalently to peptides or if they have structural features that allow them to interact with certain T-cell receptors directly. Immunohistochemical and functional studies of drug-reactive T cells in patients with distinct forms of exanthema reveal that distinct T-cell functions lead to different clinical phenotypes. In maculopapular exanthema, perforin-positive and granzyme B-positive CD4+ T cells kill activated keratinocytes, while a large number of cytotoxic CD8+ T cells in the epidermis is associated with formation of vesicles and bullae. Drug-specific T cells also orchestrate inflammatory skin reactions through the release of various cytokines (for example, interleukin-5, interferon) and chemokines (such as interleukin-8). Activation of T cells with a particular function seems to lead to a specific clinical picture (for example, bullous or pustular exanthema). Taken together, these data allow delayed hypersensitivity reactions (type IV) to be further subclassified into T-cell reactions, which through the release of certain cytokines and chemokines preferentially activate and recruit monocytes (type IVa), eosinophils (type IVb), or neutrophils (type IVd). Moreover, cytotoxic functions by either CD4+ or CD8+ T cells (type IVc) seem to participate in all type IV reactions.

  5. Lesions in the mRNA cap-binding gene ABA HYPERSENSITIVE 1 suppress FRIGIDA-mediated delayed flowering in Arabidopsis.

    PubMed

    Bezerra, Isabel C; Michaels, Scott D; Schomburg, Fritz M; Amasino, Richard M

    2004-10-01

    Recessive mutations that suppress the late-flowering phenotype conferred by FRIGIDA (FRI) and FLOWERING LOCUS C (FLC) and which also result in serrated leaf morphology were identified in T-DNA and fast-neutron mutant populations. Molecular analysis showed that the mutations are caused by lesions in the gene encoding the large subunit of the nuclear mRNA cap-binding protein, ABH1 (ABA hypersensitive1). The suppression of late flowering is caused by the inability of FRI to increase FLC mRNA levels in the abh1 mutant background. The serrated leaf morphology of abh1 is similar to the serrate (se) mutant and, like abh1, se is also a suppressor of FRI-mediated late flowering although it is a weaker suppressor than abh1. Unlike se, in abh1 the rate of leaf production and the number of juvenile leaves are not altered. The abh1 lesion affects several developmental processes, perhaps because the processing of certain mRNAs in these pathways is more sensitive to loss of cap-binding activity than the majority of cellular mRNAs. PMID:15361145

  6. Chronic loss of noradrenergic tone produces β-arrestin2-mediated cocaine hypersensitivity and alters cellular D2 responses in the nucleus accumbens.

    PubMed

    Gaval-Cruz, Meriem; Goertz, Richard B; Puttick, Daniel J; Bowles, Dawn E; Meyer, Rebecca C; Hall, Randy A; Ko, Daijin; Paladini, Carlos A; Weinshenker, David

    2016-01-01

    Cocaine blocks plasma membrane monoamine transporters and increases extracellular levels of dopamine (DA), norepinephrine (NE) and serotonin (5-HT). The addictive properties of cocaine are mediated primarily by DA, while NE and 5-HT play modulatory roles. Chronic inhibition of dopamine β-hydroxylase (DBH), which converts DA to NE, increases the aversive effects of cocaine and reduces cocaine use in humans, and produces behavioral hypersensitivity to cocaine and D2 agonism in rodents, but the underlying mechanism is unknown. We found a decrease in β-arrestin2 (βArr2) in the nucleus accumbens (NAc) following chronic genetic or pharmacological DBH inhibition, and overexpression of βArr2 in the NAc normalized cocaine-induced locomotion in DBH knockout (Dbh -/-) mice. The D2/3 agonist quinpirole decreased excitability in NAc medium spiny neurons (MSNs) from control, but not Dbh -/- animals, where instead there was a trend for an excitatory effect. The Gαi inhibitor NF023 abolished the quinpirole-induced decrease in excitability in control MSNs, but had no effect in Dbh -/- MSNs, whereas the Gαs inhibitor NF449 restored the ability of quinpirole to decrease excitability in Dbh -/- MSNs, but had no effect in control MSNs. These results suggest that chronic loss of noradrenergic tone alters behavioral responses to cocaine via decreases in βArr2 and cellular responses to D2/D3 activation, potentially via changes in D2-like receptor G-protein coupling in NAc MSNs.

  7. Chronic loss of noradrenergic tone produces β-arrestin2-mediated cocaine hypersensitivity and alters cellular D2 responses in the nucleus accumbens.

    PubMed

    Gaval-Cruz, Meriem; Goertz, Richard B; Puttick, Daniel J; Bowles, Dawn E; Meyer, Rebecca C; Hall, Randy A; Ko, Daijin; Paladini, Carlos A; Weinshenker, David

    2016-01-01

    Cocaine blocks plasma membrane monoamine transporters and increases extracellular levels of dopamine (DA), norepinephrine (NE) and serotonin (5-HT). The addictive properties of cocaine are mediated primarily by DA, while NE and 5-HT play modulatory roles. Chronic inhibition of dopamine β-hydroxylase (DBH), which converts DA to NE, increases the aversive effects of cocaine and reduces cocaine use in humans, and produces behavioral hypersensitivity to cocaine and D2 agonism in rodents, but the underlying mechanism is unknown. We found a decrease in β-arrestin2 (βArr2) in the nucleus accumbens (NAc) following chronic genetic or pharmacological DBH inhibition, and overexpression of βArr2 in the NAc normalized cocaine-induced locomotion in DBH knockout (Dbh -/-) mice. The D2/3 agonist quinpirole decreased excitability in NAc medium spiny neurons (MSNs) from control, but not Dbh -/- animals, where instead there was a trend for an excitatory effect. The Gαi inhibitor NF023 abolished the quinpirole-induced decrease in excitability in control MSNs, but had no effect in Dbh -/- MSNs, whereas the Gαs inhibitor NF449 restored the ability of quinpirole to decrease excitability in Dbh -/- MSNs, but had no effect in control MSNs. These results suggest that chronic loss of noradrenergic tone alters behavioral responses to cocaine via decreases in βArr2 and cellular responses to D2/D3 activation, potentially via changes in D2-like receptor G-protein coupling in NAc MSNs. PMID:25123018

  8. Lesions in the mRNA cap-binding gene ABA HYPERSENSITIVE 1 suppress FRIGIDA-mediated delayed flowering in Arabidopsis.

    PubMed

    Bezerra, Isabel C; Michaels, Scott D; Schomburg, Fritz M; Amasino, Richard M

    2004-10-01

    Recessive mutations that suppress the late-flowering phenotype conferred by FRIGIDA (FRI) and FLOWERING LOCUS C (FLC) and which also result in serrated leaf morphology were identified in T-DNA and fast-neutron mutant populations. Molecular analysis showed that the mutations are caused by lesions in the gene encoding the large subunit of the nuclear mRNA cap-binding protein, ABH1 (ABA hypersensitive1). The suppression of late flowering is caused by the inability of FRI to increase FLC mRNA levels in the abh1 mutant background. The serrated leaf morphology of abh1 is similar to the serrate (se) mutant and, like abh1, se is also a suppressor of FRI-mediated late flowering although it is a weaker suppressor than abh1. Unlike se, in abh1 the rate of leaf production and the number of juvenile leaves are not altered. The abh1 lesion affects several developmental processes, perhaps because the processing of certain mRNAs in these pathways is more sensitive to loss of cap-binding activity than the majority of cellular mRNAs.

  9. Hypersensitivity of Cockayne's syndrome cells to camptothecin is associated with the generation of abnormally high levels of double strand breaks in nascent DNA.

    PubMed

    Squires, S; Ryan, A J; Strutt, H L; Johnson, R T

    1993-05-01

    We report that fibroblasts from individuals with Cockayne's Syndrome (CS), an autosomal recessive disease exhibiting hypersensitivity to UV, are also hypersensitive to the killing action of camptothecin (CPT). In normal and CS cell lines the level of the protein-linked single strand DNA breaks (SSBs) induced by equal doses of CPT is similar, and these DNA breaks disappear within minutes of the removal of CPT. Thus, the toxicity of CPT does not correlate with the primary DNA lesions induced by the drug, and the hypersensitivity of CS cells cannot be explained by excessive topoisomerase I activity or by a defect in the enzyme ligation step. We have reported that CPT toxicity in normal cells is closely associated with the generation of double-strand DNA breaks (DSBs), predominantly at sites of DNA replication. The hypersensitivity of CS cells to CPT correlates closely with the much higher level of DSBs in nascent DNA than in normal cells. These DSBs are long-lived in all cells, but in CS many more (about 10-fold) remain 24 h after CPT removal and are presumably responsible for the higher frequency of chromosome aberrations in these cells. In CS as in normal cells aphidicolin prevents the generation of replication-related DSBs, suggesting that the movement of the DNA polymerase is necessary for the induction by CPT of the cytotoxic DSBs. Resistance to CPT and UV is restored to wild type in proliferating hybrids constructed between CS lines from two different complementation groups as is the abundance of replication-related DSBs. On the basis of this complementation we conclude that the UV and CPT sensitivities are distinct phenotypic traits arising from mutations in the CS A and B genes. PMID:7683249

  10. Essential oil of clove (Eugenia caryophyllata) augments the humoral immune response but decreases cell mediated immunity.

    PubMed

    Halder, Sumita; Mehta, Ashish K; Mediratta, Pramod K; Sharma, Krishna K

    2011-08-01

    The present study was undertaken to explore the effect of the essential oil isolated from the buds of Eugenia caryophyllata on some immunological parameters. Humoral immunity was assessed by measuring the hemagglutination titre to sheep red blood cells and delayed type hypersensitivity was assessed by measuring foot pad thickness. Clove oil administration produced a significant increase in the primary as well as secondary humoral immune response. In addition, it also produced a significant decrease in foot pad thickness compared with the control group. Thus, these results suggest that clove oil can modulate the immune response by augmenting humoral immunity and decreasing cell mediated immunity.

  11. Essential oil of clove (Eugenia caryophyllata) augments the humoral immune response but decreases cell mediated immunity.

    PubMed

    Halder, Sumita; Mehta, Ashish K; Mediratta, Pramod K; Sharma, Krishna K

    2011-08-01

    The present study was undertaken to explore the effect of the essential oil isolated from the buds of Eugenia caryophyllata on some immunological parameters. Humoral immunity was assessed by measuring the hemagglutination titre to sheep red blood cells and delayed type hypersensitivity was assessed by measuring foot pad thickness. Clove oil administration produced a significant increase in the primary as well as secondary humoral immune response. In addition, it also produced a significant decrease in foot pad thickness compared with the control group. Thus, these results suggest that clove oil can modulate the immune response by augmenting humoral immunity and decreasing cell mediated immunity. PMID:21796701

  12. ABA-HYPERSENSITIVE BTB/POZ PROTEIN 1 functions as a negative regulator in ABA-mediated inhibition of germination in Arabidopsis.

    PubMed

    Kim, Hani; Kim, Soon-Hee; Seo, Dong Hye; Chung, Sunglan; Kim, Sang-Woo; Lee, Jeong-Soo; Kim, Woo Taek; Lee, Jae-Hoon

    2016-02-01

    To elucidate the contribution of CRL3-ABA-mediated responses, we attempted to find CRL3 substrate receptors involved in ABA signaling. One gene named ABA-HYPERSENSITIVE BTB/POZ PROTEIN 1 (AHT1) was upregulated more than 2.5 times by ABA, and its coding region possessed a BTB/POZ domain, which is the common feature of CRL3 substrate receptors. Loss of AHT1 led to retardation of the germination process, not inhibition of root growth. AHT1 transcripts also increased in response to mannitol, NaCl and drought treatments at the seedling stage and in dry seeds. High expression of AHT1 in dry seeds was inhibited by the defect of ABA signaling components such as ABI1, ABI3 and SRKs indicating that the expression of AHT1 is dependent on ABA signaling. Among bZIP transcription factors participating in ABA signaling, the losses of ABI5/DPBF1, AREB1/ABF2, EEL/DPBF4 and DPBF2/bZIP67 resulted in reduced AHT1 expression, showing that these transcription factors play a positive role in ABA-induced AHT1 expression. While loss of AHT1 did not affect the expression pattern of NCED3, ABI2, SRKs and AREB/ABF genes, it led to hyperinduction of ABI5/DPBF genes such as ABI5/DPBF1, EEL/DPBF4 and AREB3/DPBF3, which are mainly involved in seed development and germination, as well as ABA-inducible genes transactivated by ABI5. Overall, these findings indicate that AHT1 negatively regulates ABA-mediated inhibition of germination, possibly by repressing the expression of a subset of ABI5/DPBF subfamily genes, and that AHT1 may be regulated by a negative feedback process through its linkage with a part of ABI5/DPBF proteins. PMID:26667153

  13. Lack of TAK1 in dendritic cells inhibits the contact hypersensitivity response induced by trichloroethylene in local lymph node assay.

    PubMed

    Yao, Pan; Hongqian, Chu; Qinghe, Meng; Lanqin, Shang; Jianjun, Jiang; Xiaohua, Yang; Xuetao, Wei; Weidong, Hao

    2016-09-15

    Trichloroethylene (TCE) is a ubiquitous environmental contaminant. Occupational TCE exposure has been associated with severe, generalized contact hypersensitivity (CHS) skin disorder. The development of CHS depends on innate and adaptive immune functions. Transforming growth factor-β activated kinase-1 (TAK1) controls the survival of dendritic cells (DCs) that affect the immune system homeostasis. We aimed to investigate the role of TAK1 activity in DC on TCE-induced CHS response. Control mice and DC-specific TAK1 deletion mice were treated with 80% (v/v) TCE using local lymph node assay (LLNA) to establish a TCE-induced CHS model. The draining lymph nodes (DLNs) were excised and the lymphocytes were measure for proliferation by BrdU-ELISA, T-cell phenotype analysis by flow cytometry and signaling pathway activation by western blot. The ears were harvested for histopathological analysis. Control mice in the 80% TCE group displayed an inflammatory response in the ears, increased lymphocyte proliferation, elevated regulatory T-cell and activated T-cell percentages, and more IFN-γ producing CD8(+) T cells in DLNs. In contrast to control mice, DC-specific TAK1 deletion mice in the 80% TCE group showed an abolished CHS response and this was associated with defective T-cell expansion, activation and IFN-γ production. This effect may occur through Jnk and NF-κB signaling pathways. Overall, this study demonstrates a pivotal role of TAK1 in DCs in controlling TCE-induced CHS response and suggests that targeting TAK1 function in DCs may be a viable approach to preventing and treating TCE-related occupational health hazards. PMID:27473013

  14. Localization of hydrogen peroxide accumulation during the hypersensitive reaction of lettuce cells to Pseudomonas syringae pv phaseolicola.

    PubMed Central

    Bestwick, C S; Brown, I R; Bennett, M H; Mansfield, J W

    1997-01-01

    The active oxygen species hydrogen peroxide (H2O2) was detected cytochemically by its reaction with cerium chloride to produce electron-dense deposits of cerium perhydroxides. In uninoculated lettuce leaves, H2O2 was typically present within the secondary thickened walls of xylem vessels. Inoculation with wild-type cells of Pseudomonas syringae pv phaseolicola caused a rapid hypersensitive reaction (HR) during which highly localized accumulation of H2O2 was found in plant cell walls adjacent to attached bacteria. Quantitative analysis indicated a prolonged burst of H2O2 occurring between 5 to 8 hr after inoculation in cells undergoing the HR during this example of non-host resistance. Cell wall alterations and papilla deposition, which occurred in response to both the wild-type strain and a nonpathogenic hrpD mutant, were not associated with intense staining for H2O2, unless the responding cell was undergoing the HR. Catalase treatment to decompose H2O2 almost entirely eliminated staining, but 3-amino-1,2,4-triazole (catalase inhibitor) did not affect the pattern of distribution of H2O2 detected. H2O2 production was reduced more by the inhibition of plant peroxidases (with potassium cyanide and sodium azide) than by inhibition of neutrophil-like NADPH oxidase (with diphenylene iodonium chloride). Results suggest that CeCl3 reacts with excess H2O2 that is not rapidly metabolized during cross-linking reactions occurring in cell walls; such an excess of H2O2 in the early stages of the plant-bacterium interaction was only produced during the HR. The highly localized accumulation of H2O2 is consistent with its direct role as an antimicrobial agent and as the cause of localized membrane damage at sites of bacterial attachment. PMID:9061952

  15. Lack of TAK1 in dendritic cells inhibits the contact hypersensitivity response induced by trichloroethylene in local lymph node assay.

    PubMed

    Yao, Pan; Hongqian, Chu; Qinghe, Meng; Lanqin, Shang; Jianjun, Jiang; Xiaohua, Yang; Xuetao, Wei; Weidong, Hao

    2016-09-15

    Trichloroethylene (TCE) is a ubiquitous environmental contaminant. Occupational TCE exposure has been associated with severe, generalized contact hypersensitivity (CHS) skin disorder. The development of CHS depends on innate and adaptive immune functions. Transforming growth factor-β activated kinase-1 (TAK1) controls the survival of dendritic cells (DCs) that affect the immune system homeostasis. We aimed to investigate the role of TAK1 activity in DC on TCE-induced CHS response. Control mice and DC-specific TAK1 deletion mice were treated with 80% (v/v) TCE using local lymph node assay (LLNA) to establish a TCE-induced CHS model. The draining lymph nodes (DLNs) were excised and the lymphocytes were measure for proliferation by BrdU-ELISA, T-cell phenotype analysis by flow cytometry and signaling pathway activation by western blot. The ears were harvested for histopathological analysis. Control mice in the 80% TCE group displayed an inflammatory response in the ears, increased lymphocyte proliferation, elevated regulatory T-cell and activated T-cell percentages, and more IFN-γ producing CD8(+) T cells in DLNs. In contrast to control mice, DC-specific TAK1 deletion mice in the 80% TCE group showed an abolished CHS response and this was associated with defective T-cell expansion, activation and IFN-γ production. This effect may occur through Jnk and NF-κB signaling pathways. Overall, this study demonstrates a pivotal role of TAK1 in DCs in controlling TCE-induced CHS response and suggests that targeting TAK1 function in DCs may be a viable approach to preventing and treating TCE-related occupational health hazards.

  16. Pseudomonas syringae pv. tomato cells encounter inhibitory levels of water stress during the hypersensitive response of Arabidopsis thaliana

    PubMed Central

    Wright, Catherine A.; Beattie, Gwyn A.

    2004-01-01

    During plant defense against bacterial pathogens, the hypersensitive response (HR) functions to restrict pathogen growth and spread. The mechanisms driving this growth restriction are poorly understood. We used a water stress-responsive transcriptional fusion to quantify the water potential sensed by individual Pseudomonas syringae pv. tomato DC3000 cells during infection of Arabidopsis thaliana leaves. A nonpathogenic DC3000 hrcC mutant defective in type III secretion, as well as the saprophyte Pseudomonas fluorescens A506, sensed water potentials of -0.3 to -0.4 MPa at 48 h postinfiltration (hpi). During pathogenesis, DC3000 sensed lower water potentials (-0.4 to -0.9 MPa), demonstrating that it can modify the intercellular environment, and these water potentials were associated with optimal DC3000 growth in culture. During the HR, DC3000 cells sensed water potentials (-1.6 to -2.2 MPa) that were low enough to prevent cell division in the majority of cells in culture. This water potential decrease occurred within only 4 hpi and was influenced by avirulence gene expression, with avrRpm1 expression associated with lower water potentials than avrRpt2 or avrB expression at 48 hpi. The population sizes of the DC3000 variants tested were significantly correlated with the apoplastic water potential at 48 hpi, with a decrease of -0.9 MPa associated with a 10-fold decrease in cells per gram of leaf. These results suggest that the apoplastic water potential is a determinant of endophytic bacterial population size, and water stress, resulting from high osmolarity or tissue desiccation, is at least one factor restricting bacterial growth during the HR. PMID:14981249

  17. Cell-Mediated Immune Function and Cytokine Regulation During Space Flight

    NASA Technical Reports Server (NTRS)

    Sams, Clarence F.; Pierson, Duane L.; Paloski, W. H. (Technical Monitor)

    2000-01-01

    The changes in immune function which occur during space flight potentially expose the crews to an increased risk for development of illness. Decreased cellular immune function has been repeatedly documented after space flight and confirmed during flight by in vivo delayed-type hypersensitivity testing. However, correlation of immune changes with a clinically significant risk factor has not yet been performed. Our hypothesis is that space flight induces a decrease in cell-mediated immune function accompanied by a shift from a type 1 cytokine pattern (favoring cell-mediated immunity) to a type 2 cytokine pattern (favoring humoral immunity). We further hypothesize that reactivation of latent viruses will occur during space flight in association with the decreased cellular immunity. To test these hypotheses, we will determine the effects of space flight on cell-mediated immunity and viral reactivation. We will utilize delayed-type hypersensitivity testing as an in vivo measure of integrated cell-mediated immune function. The production of cytokines and immunoregulatory factors by lymphocytes and monocytes will be measured to determine whether changes in cytokine patterns are associated with the space flight-induced immune dysregulation. Correlation of antigen-specific immune changes with reactivation of latent herpes viruses will be determined by measuring peripheral levels of viral (CMV, VZV, EBV) antigen-specific T cells and comparing to the levels of EBV-infected B-cells by fluorescence in situ hybridization and flow cytometry. A comparison of cell-mediated immune function, cytokine regulation and viral reactivation will provide new insights into crew member health risks during flight.

  18. Antigenic specificities of delayed hypersensitivity in mice to dinitrophenylated proteins

    PubMed Central

    Yonemasu, K.; Crowle, A. J.

    1973-01-01

    that control over development of delayed hypersensitivities and cell-mediated immunologic reactions may be easier than hitherto anticipated, because humoral antibodies to only a portion of an antigen molecule will suffice to control sensitization to the entire molecule. ImagesFIG. 2 PMID:4127727

  19. Structural basis of metal hypersensitivity

    PubMed Central

    Wang, Yang

    2014-01-01

    Metal hypersensitivity is a common immune disorder. Human immune systems mount the allergic attacks on metal ions through skin contacts, lung inhalation and metal-containing artificial body implants. The consequences can be simple annoyances to life-threatening systemic illness. Allergic hyper-reactivities to nickel (Ni) and beryllium (Be) are the best-studied human metal hypersensitivities. Ni-contact dermatitis affects 10 % of the human population, whereas Be compounds are the culprits of chronic Be disease (CBD). αβ T cells (T cells) play a crucial role in these hypersensitivity reactions. Metal ions work as haptens and bind to the surface of major histocompatibility complex (MHC) and peptide complex. This modifies the binding surface of MHC and triggers the immune response of T cells. Metal-specific αβ T cell receptors (TCRs) are usually MHC restricted, especially MHC class II (MHCII) restricted. Numerous models have been proposed, yet the mechanisms and molecular basis of metal hypersensitivity remain elusive. Recently, we determined the crystal structures of the Ni and Be presenting human MHCII molecules, HLA-DR52c (DRA*0101, DRB3*0301) and HLA-DP2 (DPA1*0103, DPB1*0201). These structures revealed unusual features of MHCII molecules and shed light on how metal ions are recognized by T cells. PMID:22983897

  20. Virus Infections Incite Pain Hypersensitivity by Inducing Indoleamine 2,3 Dioxygenase

    PubMed Central

    Huang, Lei; Ou, Rong; Rabelo de Souza, Guilherme; Cunha, Thiago M.; Lemos, Henrique; Mohamed, Eslam; Li, Lingqian; Pacholczyk, Gabriela; Randall, Janice; Munn, David H.; Mellor, Andrew L.

    2016-01-01

    Increased pain sensitivity is a comorbidity associated with many clinical diseases, though the underlying causes are poorly understood. Recently, chronic pain hypersensitivity in rodents treated to induce chronic inflammation in peripheral tissues was linked to enhanced tryptophan catabolism in brain mediated by indoleamine 2,3 dioxygenase (IDO). Here we show that acute influenza A virus (IAV) and chronic murine leukemia retrovirus (MuLV) infections, which stimulate robust IDO expression in lungs and lymphoid tissues, induced acute or chronic pain hypersensitivity, respectively. In contrast, virus-induced pain hypersensitivity did not manifest in mice lacking intact IDO1 genes. Spleen IDO activity increased markedly as MuLV infections progressed, while IDO1 expression was not elevated significantly in brain or spinal cord (CNS) tissues. Moreover, kynurenine (Kyn), a tryptophan catabolite made by cells expressing IDO, incited pain hypersensitivity in uninfected IDO1-deficient mice and Kyn potentiated pain hypersensitivity due to MuLV infection. MuLV infection stimulated selective IDO expression by a discreet population of spleen cells expressing both B cell (CD19) and dendritic cell (CD11c) markers (CD19+ DCs). CD19+ DCs were more susceptible to MuLV infection than B cells or conventional (CD19neg) DCs, proliferated faster than B cells from early stages of MuLV infection and exhibited mature antigen presenting cell (APC) phenotypes, unlike conventional (CD19neg) DCs. Moreover, interactions with CD4 T cells were necessary to sustain functional IDO expression by CD19+ DCs in vitro and in vivo. Splenocytes from MuLV-infected IDO1-sufficient mice induced pain hypersensitivity in uninfected IDO1-deficient recipient mice, while selective in vivo depletion of DCs alleviated pain hypersensitivity in MuLV-infected IDO1-sufficient mice and led to rapid reduction in splenomegaly, a hallmark of MuLV immune pathogenesis. These findings reveal critical roles for CD19+ DCs

  1. Antibody-mediated depletion of lymphocyte-activation gene-3 (LAG-3(+) )-activated T lymphocytes prevents delayed-type hypersensitivity in non-human primates.

    PubMed

    Poirier, N; Haudebourg, T; Brignone, C; Dilek, N; Hervouet, J; Minault, D; Coulon, F; de Silly, R V; Triebel, F; Blancho, G; Vanhove, B

    2011-05-01

    Lymphocyte-activation gene-3 (LAG-3, CD223) is a marker for recently activated effector T cells. Activated T lymphocytes are of major importance in many autoimmune diseases and organ transplant rejection. Therefore, specifically depleting LAG-3(+) T cells might lead to targeted immunosuppression that would spare resting T cells while eliminating pathogenic activated T cells. We have shown previously that anti-LAG-3 antibodies sharing depleting as well as modulating activities inhibit heart allograft rejection in rats. Here, we have developed and characterized a cytotoxic LAG-3 chimeric antibody (chimeric A9H12), and evaluated its potential as a selective therapeutic depleting agent in a non-human primate model of delayed-type hypersensitivity (DTH). Chimeric A9H12 showed a high affinity to its antigen and depleted both cytomegalovirus (CMV)-activated CD4(+) and CD8(+) human T lymphocytes in vitro. In vivo, a single intravenous injection at either 1 or 0·1 mg/kg was sufficient to deplete LAG-3(+) -activated T cells in lymph nodes and to prevent the T helper type 1 (Th1)-driven skin inflammation in a tuberculin-induced DTH model in baboons. T lymphocyte and macrophage infiltration into the skin was also reduced. The in vivo effect was long-lasting, as several weeks to months were required after injection to restore a positive reaction after antigen challenge. Our data confirm that LAG-3 is a promising therapeutic target for depleting antibodies that might lead to higher therapeutic indexes compared to traditional immunosuppressive agents in autoimmune diseases and transplantation. PMID:21352204

  2. Expression and inheritance of hypersensitive resistance to rice hoja blanca virus mediated by the viral nucleocapsid protein gene in transgenic rice.

    PubMed

    Lentini, Z; Lozano, I; Tabares, E; Fory, L; Domínguez, J; Cuervo, M; Calvert, L

    2003-04-01

    Rice hoja blanca virus (RHBV) is a major virus disease of economic importance affecting rice in northern South America, Central America and the Caribbean. This is the first report of transgenic resistance to RHBV and the transformation of an indica rice variety from Latin America. Rice transformed with the RHBV nucleocapsid protein ( N) gene had a significant reduction in disease development. Several reactions were observed that ranged from susceptible to completely resistant plants (immunity). The resistant reactions were characterized by the production of local lesions like a hypersensitive reaction or a recovery phenotype with the emergence of symptom-less new leaves. These transgenic RHBV-resistant rice lines expressed the N gene RNA at low levels that were below the detection limit by Northern blots and only resolved by RT-PCR. The nucleocapsid protein could not be detected in any of the transgenic plants either by Western or ELISA tests. These results suggest that the resistance encoded by the N gene in these plants appears to be mediated by RNA. When challenged with RHBV, the resistant transgenic lines showed a significant increased performance for important agronomic traits including the number of tillers, the number of grains per plant and the yield as compared to the susceptible control. Furthermore, upon inoculation some of the most-resistant transgenic lines showed agronomic traits similar to the uninoculated non-transgenic Cica 8 control. Using both agronomic traits and disease severity as criteria, several of the most-resistant lines were followed through the R(4) generation and demonstrated that the N gene and RHBV resistance was inherited in a stable manner. These transgenic rice lines could become a new genetic resource in developing RHBV-resistant cultivars. PMID:12671749

  3. Hypersensitivity Induced by Activation of Spinal Cord PAR2 Receptors Is Partially Mediated by TRPV1 Receptors

    PubMed Central

    Mrozkova, Petra; Spicarova, Diana; Palecek, Jiri

    2016-01-01

    Protease-activated receptors 2 (PAR2) and transient receptor potential vanilloid 1 (TRPV1) receptors in the peripheral nerve endings are implicated in the development of increased sensitivity to mechanical and thermal stimuli, especially during inflammatory states. Both PAR2 and TRPV1 receptors are co-expressed in nociceptive dorsal root ganglion (DRG) neurons on their peripheral endings and also on presynaptic endings in the spinal cord dorsal horn. However, the modulation of nociceptive synaptic transmission in the superficial dorsal horn after activation of PAR2 and their functional coupling with TRPV1 is not clear. To investigate the role of spinal PAR2 activation on nociceptive modulation, intrathecal drug application was used in behavioural experiments and patch-clamp recordings of spontaneous, miniature and dorsal root stimulation-evoked excitatory postsynaptic currents (sEPSCs, mEPSCs, eEPSCs) were performed on superficial dorsal horn neurons in acute rat spinal cord slices. Intrathecal application of PAR2 activating peptide SLIGKV-NH2 induced thermal hyperalgesia, which was prevented by pretreatment with TRPV1 antagonist SB 366791 and was reduced by protein kinases inhibitor staurosporine. Patch-clamp experiments revealed robust decrease of mEPSC frequency (62.8 ± 4.9%), increase of sEPSC frequency (127.0 ± 5.9%) and eEPSC amplitude (126.9 ± 12.0%) in dorsal horn neurons after acute SLIGKV-NH2 application. All these EPSC changes, induced by PAR2 activation, were prevented by SB 366791 and staurosporine pretreatment. Our results demonstrate an important role of spinal PAR2 receptors in modulation of nociceptive transmission in the spinal cord dorsal horn at least partially mediated by activation of presynaptic TRPV1 receptors. The functional coupling between the PAR2 and TRPV1 receptors on the central branches of DRG neurons may be important especially during different pathological states when it may enhance pain perception. PMID:27755539

  4. Harpin Mediates Cell Aggregation in Erwinia chrysanthemi 3937

    PubMed Central

    Yap, Mee-Ngan; Rojas, Clemencia M.; Yang, Ching-Hong; Charkowski, Amy O.

    2006-01-01

    The hypersensitive response elicitor harpin (HrpN) of soft rot pathogen Erwinia chrysanthemi strains 3937 and EC16 is secreted via the type III secretion system and remains cell surface bound. Strain 3937 HrpN is essential for cell aggregation, but the C-terminal one-third of the protein is not required for aggregative activity. PMID:16513758

  5. Drug hypersensitivity syndrome.

    PubMed

    Kumari, Rashmi; Timshina, Dependra K; Thappa, Devinder Mohan

    2011-01-01

    Drug hypersensitivity syndrome (DHS) is an adverse drug reaction commonly associated with the aromatic antiepileptic drugs (AEDs), viz., phenytoin (PHT), carbamazepine (CBZ), phenobarbital (PB), lamotrigine, primidone, etc. It can also be caused by other drugs, such as sulfonamides, dapsone, minocycline, gold derivatives, cyclosporine, captopril, diltiazem, terbinafine, azathioprine and allopurinol. Diagnosis of DHS may be difficult because of the variety of clinical and laboratory abnormalities and manifestations and because the syndrome may mimic infectious, neoplastic or collagen vascular disorders. The risk for developing hypersensitivity within 60 days of the first or second prescription in new users of PHT or CBZ was estimated to be 2.3-4.5 per 10,000 and 1-4.1 per 10,000, respectively. The syndrome is defined by the fever, skin rash, lymphadenopathy and internal organ involvement within the first 2-8 weeks after initiation of therapy. Internal manifestations include, among others, agranulocytosis, hepatitis, nephritis and myositis. Insufficient detoxification may lead to cell death or contribute to the formation of antigen that triggers an immune reaction. Cross-reactivity among PHT, CBZ and PB is as high as 70%-80%. Management mainly includes immediate withdrawal of the culprit drug, symptomatic treatment and systemic steroids or immunoglobulins.

  6. Influence of Ganoderma lucidum (Curt.: Fr.) P. Karst. on T-cell-mediated immunity in normal and immunosuppressed mice line CBA/Ca.

    PubMed

    Nizhenkovska, Iryna V; Pidchenko, Vitalii T; Bychkova, Nina G; Bisko, Nina A; Rodnichenko, Angela Y; Kozyko, Natalya O

    2015-09-01

    The article presents the results of the investigation of the effect of biomass powder of the fungus Ganoderma lucidum on T-cell-mediated immunity in normal and immunosuppressed mice CBA/Ca. Delayed-type hypersensitivity assay was used. Experimental immunodeficiency was established with intraperitoneal injection of the immunosuppressant cyclophosphamide at a single dose of 150 mg/kg on the first day of the experiment. Results of the study show that the administration of biomass powder of Ganoderma lucidum in a dose of 0.5 mg/kg orally for 10 days increases the delayed-type hypersensitivity response in normal mice CBA/Ca. Administration of 0.5 mg/kg of biomass powder of the fungus Ganoderma lucidum for 10 days blocked the development of the T-cell-mediated immunosuppression, induced by administration of cyclophosphamide and restored the delayed-type hypersensitivity response in immunosuppressed mice. Key words: fungus Ganoderma lucidum cyclophosphamide immunodeficiency T-cell-mediated immunity delayed-type hypersensitivity. PMID:26459128

  7. Influence of Ganoderma lucidum (Curt.: Fr.) P. Karst. on T-cell-mediated immunity in normal and immunosuppressed mice line CBA/Ca.

    PubMed

    Nizhenkovska, Iryna V; Pidchenko, Vitalii T; Bychkova, Nina G; Bisko, Nina A; Rodnichenko, Angela Y; Kozyko, Natalya O

    2015-09-01

    The article presents the results of the investigation of the effect of biomass powder of the fungus Ganoderma lucidum on T-cell-mediated immunity in normal and immunosuppressed mice CBA/Ca. Delayed-type hypersensitivity assay was used. Experimental immunodeficiency was established with intraperitoneal injection of the immunosuppressant cyclophosphamide at a single dose of 150 mg/kg on the first day of the experiment. Results of the study show that the administration of biomass powder of Ganoderma lucidum in a dose of 0.5 mg/kg orally for 10 days increases the delayed-type hypersensitivity response in normal mice CBA/Ca. Administration of 0.5 mg/kg of biomass powder of the fungus Ganoderma lucidum for 10 days blocked the development of the T-cell-mediated immunosuppression, induced by administration of cyclophosphamide and restored the delayed-type hypersensitivity response in immunosuppressed mice. Key words: fungus Ganoderma lucidum cyclophosphamide immunodeficiency T-cell-mediated immunity delayed-type hypersensitivity.

  8. DEPRESSED CELL-MEDIATED IMMUNITY IN PATIENTS WITH PRIMARY INTRACRANIAL TUMORS

    PubMed Central

    Brooks, William H.; Netsky, Martin G.; Normansell, David E.; Horwitz, David A.

    1972-01-01

    Tumor immunity in patients with primary intracranial tumors was assessed in relation to the general status of host immunocompetence. Lymphocyte sensitization to tumor-specific membrane antigens was demonstrated by the proliferative response of lymphocytes in the presence of autochthonous tumor cells. Paradoxically, one-half of the patients could not be sensitized to a primary antigen, dinitrochlorobenzene; existing delayed hypersensitivity was also depressed, as measured by skin tests and lymphocyte transformation in response to common antigens. A heat-stable factor in patients' sera blocked cell-mediated tumor immunity. In addition, these "enhancing" sera consistently suppressed the blastogenic response of autologous and homologous lymphocytes to phytohemagglutinin and to membrane antigens on allogeneic cells in the one-way mixed lymphocyte culture. When patients' leukocytes were washed and autologous plasma replaced with normal plasma, reactivity in the mixed lymphocyte culture increased to normal values. In vitro immunosuppressive activity in patients' plasma or sera correlated with depressed delayed hypersensitivity. After removal of the tumor, suppressor activity disappeared. IgG fractions of patient sera contained strong immunosuppressive activity. These data suggest that the suppressor factor may be an isoantibody elicited by the tumor that also binds to receptors on the lymphocyte membrane. In addition to specifically blocking cell-mediated tumor immunity, enhancing sera may broadly depress host immunocompetence. PMID:4345108

  9. Practical Management of Patients with a History of Immediate Hypersensitivity to Common non-Beta-Lactam Drugs.

    PubMed

    Macy, Eric

    2016-01-01

    Immediate hypersensitivity reactions to medications are among the most feared adverse drug reactions, because of their close association with anaphylaxis. This review discusses a practical management approach for patients with a history of an immediate hypersensitivity to a non-beta-lactam medication, where reexposure to the implicated, or similar, medication is clinically necessary. Mechanisms associated with severe immediate hypersensitivity reactions include IgE-mediated mast cell activation, complement-mediated mast cell activation, and direct mast cell activation. Immediate hypersensitivity reactions may also be mediated by vasodilators, other pharmacologic mechanisms, or be secondary to underlying patient-specific biochemical abnormalities such as endocrine tumors or chronic spontaneous urticaria. The key features in the reaction history and the biochemistry of the implicated medication are discussed. Most individuals with a history of immediate hypersensitivity to a medication, who require reuse of that drug, can be safely retreated with a therapeutic course of the implicated drug after a full-dose challenge, graded challenge, or desensitization, with or without premedication and/or any preliminary diagnostic testing, depending on the specific situation.

  10. A case of hypersensitivity to mosquito bites without peripheral natural killer cell lymphocytosis in a 6-year-old Korean boy.

    PubMed

    Seon, Han-Su; Roh, Ji-Hyeon; Lee, Seung-Ho; Kang, Eun-Kyeong

    2013-01-01

    Hypersensitivity to mosquito bites (HMB) is a rare disease characterized by intense skin reactions such as bulla and necrotic ulcerations at bite sites, accompanied by general symptoms such as high-grade fever and malaise occurred after mosquito bites. It has been suggested that HMB is associated with chronic Epstein-Barr virus (EBV) infection and natural killer (NK) cell leukemia/lymphoma. We describe here a Korean child who presented with 3-yr history of HMB without natural killer cell lymphocytosis. He has been ill for 6 yr with HMB. Close observation and examination for the development of lymphoproliferative status or hematologic malignant disorders is needed.

  11. Effect of microencapsulated ampicillin on cell-mediated immune responses in mice.

    PubMed

    Barsoum, I S; Kopydlowski, K M; Burge, J R; Setterstrom, J A

    1997-11-01

    The effects of free ampicillin, microencapsulated ampicillin anhydrate (MEAA) and antibiotic-free microspheres on the cell-mediated immune response in Balb/c mice were measured by lymphoproliferation assay, delayed-type hypersensitivity (DTH) and cytokine production. Injection into mice for seven consecutive days with equivalent subcutaneous doses of ampicillin, MEAA or placebo microspheres did not produce any consistent change in lymphocyte proliferation nor did it affect DTH responses or interleukin-2 production. Although the production of interleukin-4 in mice treated with ampicillin or MEAA increased compared with the control mice, this increase was not statistically significant. These results indicate that ampicillin and MEAA have similar effects on cell-mediated immunity in mice. PMID:9421323

  12. New approaches for predicting T cell-mediated drug reactions: A role for inducible and potentially preventable autoimmunity.

    PubMed

    Michels, Aaron W; Ostrov, David A

    2015-08-01

    Adverse drug reactions (ADRs) are commonplace and occur when a drug binds to its intended pharmacologic target (type A ADR) or an unintended target (type B ADR). Immunologically mediated type B ADRs, such as drug hypersensitivity syndrome, drug reaction with eosinophilia and systemic symptoms syndrome, and Stevens-Johnson syndrome/toxic epidermal necrolysis, can be severe and result in a diverse set of clinical manifestations that include fever and rash, as well as multiple organ failure (liver, kidney, lungs, and/or heart) in the case of drug hypersensitivity syndrome. There is increasing evidence that specific HLA alleles influence the risk of drug reactions. Several features of T cell-mediated ADRs are strikingly similar to those displayed by patients with autoimmune diseases like type I diabetes, such as strong HLA association, organ-specific adaptive immune responses, viral involvement, and activation of innate immunity. There is a need to better predict patient populations at risk for immunologically mediated type B ADRs. Because methods to predict type 1 diabetes by using genetic and immunologic biomarkers have been developed to a high level of accuracy (predicting 100% of subjects likely to progress), new research strategies based on these methods might also improve the ability to predict drug hypersensitivity. PMID:26254052

  13. A genome-wide association study of the maize hypersensitive defense response identifies genes that cluster in related pathways

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Much remains unknown of molecular events controling the plant hypersensitive response (HR), a rapid localized cell death that limits pathogen spread and is mediated by resistance (R-) genes. Natural modifiers of the ectopic HR phenotype induced by an aberrant auto-active R-gene (Rp1-D21), were mappe...

  14. Embryonic stem cells lacking the epigenetic regulator Cfp1 are hypersensitive to DNA-damaging agents and exhibit decreased Ape1/Ref-1 protein expression and endonuclease activity.

    PubMed

    Tate, Courtney M; Fishel, Melissa L; Holleran, Julianne L; Egorin, Merrill J; Skalnik, David G

    2009-12-01

    Modulation of chromatin structure plays an important role in the recruitment and function of DNA repair proteins. CXXC finger protein 1 (Cfp1), encoded by the CXXC1 gene, is essential for mammalian development and is an important regulator of chromatin structure. Murine embryonic stem (ES) cells lacking Cfp1 (CXXC1(-/-)) are viable but demonstrate a dramatic decrease in cytosine methylation, altered histone methylation, and an inability to differentiate. We find that ES cells lacking Cfp1 are hypersensitive to a variety of DNA-damaging agents. In addition, CXXC1(-/-) ES cells accumulate more DNA damage and exhibit decreased protein expression and endonuclease activity of AP endonuclease (Ape1/Ref-1), an enzyme involved in DNA base excision repair. Expression in CXXC1(-/-) ES cells of either the amino half of Cfp1 (amino acids 1-367) or the carboxyl half of Cfp1 (amino acids 361-656) restores normal Ape1/Ref-1 protein expression and rescues the hypersensitivity to DNA-damaging agents, demonstrating that Cfp1 contains redundant functional domains. Furthermore, retention of either the DNA-binding activity of Cfp1 or interaction with the Setd1A and Setd1B histone H3-Lys4 methyltransferase complexes is required to restore normal sensitivity of CXXC1(-/-) ES cells to DNA-damaging agents. These results implicate Cfp1 as a regulator of DNA repair processes. PMID:19836314

  15. Use of tetanus toxoid for testing cell-mediated immunity.

    PubMed

    Whittingham, S; Feery, B; Mackay, I R

    1982-10-01

    Tetanus toxoid was assessed as a skin test antigen for the measurement of cutaneous delayed-type hypersensitivity (DTH) by comparing the responses to intradermal injections of aqueous tetanus toxoid and an extract of Candida albicans in 50 randomly selected healthy adults and 10 adults with immunodeficiency. Of 42 healthy subjects previously immunised with tetanus toxoid, 33 (79%) reacted to tetanus toxoid and 33 (79%) reacted to Candida albicans. Of eight non-immunised subjects, none reacted to tetanus toxoid although five reacted to Candida albicans. Ten immunodeficient adults previously shown to be anergic to a standard panel of five skin test antigens including Candida albicans, and who had received primary immunisation and booster doses of tetanus toxoid, were anergic on current testing with tetanus toxoid and Candida albicans. Tetanus toxoid in previously immunised subjects has certain advantages as a "recall" DTH test antigen over the standard skin test antigens candidin, mumps, trichophyton, tuberculin and streptokinase-streptodornase used to diagnose cell-mediated immuno-deficiency. It is a sensitive measurement of DTH, it recalls a defined immunological event, it has a low incidence of side effects, and it produces a slight but beneficial boosting of serum antibody to tetanus toxoid.

  16. Hypersensitivity to antineoplastic agents: mechanisms and treatment with rapid desensitization.

    PubMed

    Castells, Mariana; Sancho-Serra, Maria del Carmen; Simarro, Maria

    2012-09-01

    Hypersensitivity reactions (HSRs) to chemotherapy drugs, such as taxanes and platins, and to monoclonal antibodies limit their therapeutic use due to the severity of some reactions and the fear of inducing a potentially lethal reaction in highly sensitized patients. Patients who experience hypersensitivity reactions face the prospect of abandoning first-line treatment and switching to a second-line, less effective therapy. Some of these reactions are mast cell-mediated hypersensitivity reactions, a subset of which occur through an immunoglobulin (IgE)-dependent mechanism, and are thus true allergies. Others involve mast cells without a demonstrable IgE mechanism. Whether basophils can participate in these reactions has not been demonstrated. Rapid drug desensitization (RDD) is a procedure that induces temporary tolerance to a drug, allowing a medication allergic patient to receive the optimal agent for his or her disease. Through RDD, patients with IgE and non-IgE HSRs can safely be administered important medications while minimizing or completely inhibiting adverse reactions. Due to the clinical expansion and success of RDD, the molecular mechanisms inducing the temporary tolerization have been investigated and are partially understood, allowing for safer and more effective protocols. This article reviews the current literature on molecular mechanisms of RDD with an emphasis in our recent contributions to this field as well as the indications, methods and outcomes of RDD for taxanes, platins, and monoclonal antibodies. PMID:22576054

  17. Hypersensitivity of skin fibroblasts from basal cell nevus syndrome patients to killing by ultraviolet B but not by ultraviolet C radiation

    SciTech Connect

    Applegate, L.A.; Goldberg, L.H.; Ley, R.D.; Ananthaswamy, H.N. )

    1990-02-01

    Basal cell nevus syndrome (BCNS) is an autosomal dominant genetic disorder in which the afflicted individuals are extremely susceptible to sunlight-induced skin cancers, particularly basal cell carcinomas. However, the cellular and molecular basis for BCNS is unknown. To ascertain whether there is any relationship between genetic predisposition to skin cancer and increased sensitivity of somatic cells from BCNS patients to killing by UV radiation, we exposed skin fibroblasts established from unexposed skin biopsies of several BCNS and age- and sex-matched normal individuals to either UV-B (280-320 nm) or UV-C (254 nm) radiation and determined their survival. The results indicated that skin fibroblasts from BCNS patients were hypersensitive to killing by UV-B but not UV-C radiation as compared to skin fibroblasts from normal individuals. DNA repair studies indicated that the increased sensitivity of BCNS skin fibroblasts to killing by UV-B radiation was not due to a defect in the excision repair of pyrimidine dimers. These results indicate that there is an association between hypersensitivity of somatic cells to killing by UV-B radiation and the genetic predisposition to skin cancer in BCNS patients. In addition, these results suggest that DNA lesions (and repair processes) other than the pyrimidine dimer are also involved in the pathogenesis of sunlight-induced skin cancers in BCNS patients. More important, the UV-B sensitivity assay described here may be used as a diagnostic tool to identify presymptomatic individuals with BCNS.

  18. Food hypersensitivity in a cat.

    PubMed

    Medleau, L; Latimer, K S; Duncan, J R

    1986-09-15

    Food hypersensitivity was diagnosed in a 4-year-old Siamese cat. Clinical signs included intense erythema, with alopecia, excoriations, erosions, and crusts involving the ventral portion of the abdomen, inguinal region, medial aspect of each thigh, and cranial and lateral aspects of all 4 limbs. The cat was intensely pruritic. Histologically, there was cutaneous mast cell hyperplasia and diffuse infiltration of eosinophils in the dermis. Blood eosinophilia also was found. Clinical signs resolved after exclusive feeding of a hypoallergenic diet.

  19. Cells Deficient in the Fanconi Anemia Protein FANCD2 are Hypersensitive to the Cytotoxicity and DNA Damage Induced by Coffee and Caffeic Acid

    PubMed Central

    Burgos-Morón, Estefanía; Calderón-Montaño, José Manuel; Orta, Manuel Luis; Guillén-Mancina, Emilio; Mateos, Santiago; López-Lázaro, Miguel

    2016-01-01

    Epidemiological studies have found a positive association between coffee consumption and a lower risk of cardiovascular disorders, some cancers, diabetes, Parkinson and Alzheimer disease. Coffee consumption, however, has also been linked to an increased risk of developing some types of cancer, including bladder cancer in adults and leukemia in children of mothers who drink coffee during pregnancy. Since cancer is driven by the accumulation of DNA alterations, the ability of the coffee constituent caffeic acid to induce DNA damage in cells may play a role in the carcinogenic potential of this beverage. This carcinogenic potential may be exacerbated in cells with DNA repair defects. People with the genetic disease Fanconi Anemia have DNA repair deficiencies and are predisposed to several cancers, particularly acute myeloid leukemia. Defects in the DNA repair protein Fanconi Anemia D2 (FANCD2) also play an important role in the development of a variety of cancers (e.g., bladder cancer) in people without this genetic disease. This communication shows that cells deficient in FANCD2 are hypersensitive to the cytotoxicity (clonogenic assay) and DNA damage (γ-H2AX and 53BP1 focus assay) induced by caffeic acid and by a commercial lyophilized coffee extract. These data suggest that people with Fanconi Anemia, or healthy people who develop sporadic mutations in FANCD2, may be hypersensitive to the carcinogenic activity of coffee. PMID:27399778

  20. Cells Deficient in the Fanconi Anemia Protein FANCD2 are Hypersensitive to the Cytotoxicity and DNA Damage Induced by Coffee and Caffeic Acid.

    PubMed

    Burgos-Morón, Estefanía; Calderón-Montaño, José Manuel; Orta, Manuel Luis; Guillén-Mancina, Emilio; Mateos, Santiago; López-Lázaro, Miguel

    2016-01-01

    Epidemiological studies have found a positive association between coffee consumption and a lower risk of cardiovascular disorders, some cancers, diabetes, Parkinson and Alzheimer disease. Coffee consumption, however, has also been linked to an increased risk of developing some types of cancer, including bladder cancer in adults and leukemia in children of mothers who drink coffee during pregnancy. Since cancer is driven by the accumulation of DNA alterations, the ability of the coffee constituent caffeic acid to induce DNA damage in cells may play a role in the carcinogenic potential of this beverage. This carcinogenic potential may be exacerbated in cells with DNA repair defects. People with the genetic disease Fanconi Anemia have DNA repair deficiencies and are predisposed to several cancers, particularly acute myeloid leukemia. Defects in the DNA repair protein Fanconi Anemia D2 (FANCD2) also play an important role in the development of a variety of cancers (e.g., bladder cancer) in people without this genetic disease. This communication shows that cells deficient in FANCD2 are hypersensitive to the cytotoxicity (clonogenic assay) and DNA damage (γ-H2AX and 53BP1 focus assay) induced by caffeic acid and by a commercial lyophilized coffee extract. These data suggest that people with Fanconi Anemia, or healthy people who develop sporadic mutations in FANCD2, may be hypersensitive to the carcinogenic activity of coffee. PMID:27399778

  1. Involvement of Histamine and RhoA/ROCK in Penicillin Immediate Hypersensitivity Reactions.

    PubMed

    Han, Jiayin; Yi, Yan; Li, Chunying; Zhang, Yushi; Wang, Lianmei; Zhao, Yong; Pan, Chen; Liang, Aihua

    2016-01-01

    The mechanism of penicillin immediate hypersensitivity reactions has not been completely elucidated. These reactions are generally considered to be mediated by IgE, but penicillin-specific IgE could not be detected in most cases. This study demonstrated that penicillin was able to cause vascular hyperpermeability in a mouse model mimicking clinical symptoms of penicillin immediate hypersensitivity reactions. The first exposure to penicillin also induced immediate edema and exudative reactions in ears and lungs of mice in a dose-dependent manner. Vasodilation was noted in microvessels in ears. These reactions were unlikely to be immune-mediated reactions, because no penicillin-specific IgE was produced. Furthermore, penicillin treatment directly elicited rapid histamine release. Penicillin also led to F-actin reorganization in human umbilical vein endothelial cells and increased the permeability of the endothelial monolayer. Activation of the RhoA/ROCK signaling pathway was observed in ears and lungs of mice and in endothelial cells after treatment with penicillin. Both an anti-histamine agent and a ROCK inhibitor attenuated penicillin immediate hypersensitivity reactions in mice. This study presents a novel mechanism of penicillin immediate hypersensitivity reactions and suggests a potential preventive approach against these reactions. PMID:27619816

  2. Involvement of Histamine and RhoA/ROCK in Penicillin Immediate Hypersensitivity Reactions

    PubMed Central

    Han, Jiayin; Yi, Yan; Li, Chunying; Zhang, Yushi; Wang, Lianmei; Zhao, Yong; Pan, Chen; Liang, Aihua

    2016-01-01

    The mechanism of penicillin immediate hypersensitivity reactions has not been completely elucidated. These reactions are generally considered to be mediated by IgE, but penicillin-specific IgE could not be detected in most cases. This study demonstrated that penicillin was able to cause vascular hyperpermeability in a mouse model mimicking clinical symptoms of penicillin immediate hypersensitivity reactions. The first exposure to penicillin also induced immediate edema and exudative reactions in ears and lungs of mice in a dose-dependent manner. Vasodilation was noted in microvessels in ears. These reactions were unlikely to be immune-mediated reactions, because no penicillin-specific IgE was produced. Furthermore, penicillin treatment directly elicited rapid histamine release. Penicillin also led to F-actin reorganization in human umbilical vein endothelial cells and increased the permeability of the endothelial monolayer. Activation of the RhoA/ROCK signaling pathway was observed in ears and lungs of mice and in endothelial cells after treatment with penicillin. Both an anti-histamine agent and a ROCK inhibitor attenuated penicillin immediate hypersensitivity reactions in mice. This study presents a novel mechanism of penicillin immediate hypersensitivity reactions and suggests a potential preventive approach against these reactions. PMID:27619816

  3. Treatment of dentin hypersensitivity.

    PubMed

    Trushkowsky, Richard D; Oquendo, Anabella

    2011-07-01

    Dentinal hypersensitivity is exemplified by brief, sharp, well-localized pain in response to thermal, evaporative, tactile, osmotic, or chemical stimuli that cannot be ascribed to any other form of dental defect or pathology. Pulpal pain is usually more prolonged, dull, aching, and poorly localized and lasts longer than the applied stimulus. Up to 30% of adults have dentinal hypersensitivity at some time. Current techniques for treatment may be only transient in nature and results are not always predictable. Two methods of treatment of dentin hypersensitivity are tubular occlusion and blockage of nerve activity. A differential diagnosis needs to be accomplished before any treatment. PMID:21726693

  4. Fibronectin mediates mesendodermal cell fate decisions

    PubMed Central

    Cheng, Paul; Andersen, Peter; Hassel, David; Kaynak, Bogac L.; Limphong, Pattraranee; Juergensen, Lonny; Kwon, Chulan; Srivastava, Deepak

    2013-01-01

    Non-cell-autonomous signals often play crucial roles in cell fate decisions during animal development. Reciprocal signaling between endoderm and mesoderm is vital for embryonic development, yet the key signals and mechanisms remain unclear. Here, we show that endodermal cells efficiently promote the emergence of mesodermal cells in the neighboring population through signals containing an essential short-range component. The endoderm-mesoderm interaction promoted precardiac mesoderm formation in mouse embryonic stem cells and involved endodermal production of fibronectin. In vivo, fibronectin deficiency resulted in a dramatic reduction of mesoderm accompanied by endodermal expansion in zebrafish embryos. This event was mediated by regulation of Wnt signaling in mesodermal cells through activation of integrin-β1. Our findings highlight the importance of the extracellular matrix in mediating short-range signals and reveal a novel function of endoderm, involving fibronectin and its downstream signaling cascades, in promoting the emergence of mesoderm. PMID:23715551

  5. Platinum hypersensitivity and desensitization.

    PubMed

    Miyamoto, Shingo; Okada, Rika; Ando, Kazumichi

    2015-09-01

    Platinum agents are drugs used for various types of cancer. With increased frequency of administration of platinum agents, hypersensitivity reactions appear more frequently, occurring in over 25% of cases from the seventh cycle or second line onward. It then becomes difficult to conduct treatment using these agents. Various approaches have been investigated to address hypersensitivity reactions to platinum agents. Desensitization, which gradually increases the concentration of the anticancer drug considered to be the antigen until the target dosage, has been reported as being particularly effective, with a success rate of 80-100%. The aims of this paper are to present the current findings regarding hypersensitivity reactions to platinum agents and to discuss attempts of using desensitization against hypersensitivity reactions worldwide.

  6. The N protein of Tomato spotted wilt virus (TSWV) is associated with the induction of programmed cell death (PCD) in Capsicum chinense plants, a hypersensitive host to TSWV infection.

    PubMed

    Lovato, Fernanda Antinolfi; Inoue-Nagata, Alice Kazuko; Nagata, Tatsuya; de Avila, Antônio Carlos; Pereira, Luiz Alfredo Rodrigues; Resende, Renato Oliveira

    2008-11-01

    In sweet pepper, the Tsw gene, originally described in Capsicum chinense, has been widely used as an efficient gene for inducing a hypersensitivity response (HR) derived Tomato spotted wilt virus (TSWV) resistance. Since previously reported studies suggested that the TSWV-S RNA mutation(s) are associated with the breakdown of Tsw mediated TSWV resistance in peppers, the TSWV genes N (structural nucleocapsid protein) and NS(S) (non-structural silencing suppressor protein) were cloned into a Potato virus X (PVX)-based expression vector, and inoculated into the TSWV-resistant C. chinense genotype, PI 159236, to identify the Tsw-HR viral elicitor. Typical HR-like chlorotic and necrotic lesions followed by leaf abscission were observed only in C. chinense plants inoculated with the PVX-N construct. Cytopathological analyses of these plants identified fragmented genomic DNA, indicative of programmed cell death (PCD), in mesophyll cell nuclei surrounding PVX-N-induced necrotic lesions. The other constructs induced only PVX-like symptoms without HR-like lesions and there were no microscopic signs of PCD. The mechanism of TSWV N-gene HR induction is apparently species specific as the N gene of a related tospovirus, Tomato chlorotic spot virus, was not a HR elicitor and did not cause PCD in infected cells.

  7. Immediate and Delayed Hypersensitivity Reactions to Proton Pump Inhibitors: Evaluation and Management.

    PubMed

    Otani, Iris M; Banerji, Aleena

    2016-03-01

    PPIs are among the most commonly administered medications in the USA and are generally well tolerated. Immediate and delayed immune-mediated hypersensitivity reactions are rare but increasingly recognized adverse effects of proton pump inhibitors (PPIs). Immediate hypersensitivity reactions can occur due to IgE-mediated hypersensitivity to PPIs and can be evaluated by immediate hypersensitivity skin testing and oral provocation challenge testing. A desensitization protocol can be used when PPI use cannot be avoided in an allergic patient. Delayed hypersensitivity reactions to PPIs have also been reported. Occupational exposures causing cutaneous reactions to PPIs are the most commonly reported delayed hypersensitivity reaction, followed by drug-induced subacute cutaneous lupus erythematosus. This review presents a summary of the clinical presentation, diagnostic evaluation, and management of immune-mediated hypersensitivity reactions to PPIs.

  8. Hypersensitivity Responses in the Central Nervous System

    PubMed Central

    Khorooshi, Reza; Asgari, Nasrin; Mørch, Marlene Thorsen; Berg, Carsten Tue; Owens, Trevor

    2015-01-01

    Immune-mediated tissue damage or hypersensitivity can be mediated by autospecific IgG antibodies. Pathology results from activation of complement, and antibody-dependent cellular cytotoxicity, mediated by inflammatory effector leukocytes include macrophages, natural killer cells, and granulocytes. Antibodies and complement have been associated to demyelinating pathology in multiple sclerosis (MS) lesions, where macrophages predominate among infiltrating myeloid cells. Serum-derived autoantibodies with predominant specificity for the astrocyte water channel aquaporin-4 (AQP4) are implicated as inducers of pathology in neuromyelitis optica (NMO), a central nervous system (CNS) demyelinating disease where activated neutrophils infiltrate, unlike in MS. The most widely used model for MS, experimental autoimmune encephalomyelitis, is an autoantigen-immunized disease that can be transferred to naive animals with CD4+ T cells, but not with antibodies. By contrast, NMO-like astrocyte and myelin pathology can be transferred to mice with AQP4–IgG from NMO patients. This is dependent on complement, and does not require T cells. Consistent with clinical observations that interferon-beta is ineffective as a therapy for NMO, NMO-like pathology is significantly reduced in mice lacking the Type I IFN receptor. In MS, there is evidence for intrathecal synthesis of antibodies as well as blood–brain barrier (BBB) breakdown, whereas in NMO, IgG accesses the CNS from blood. Transfer models involve either direct injection of antibody and complement to the CNS, or experimental manipulations to induce BBB breakdown. We here review studies in MS and NMO that elucidate roles for IgG and complement in the induction of BBB breakdown, astrocytopathy, and demyelinating pathology. These studies point to significance of T-independent effector mechanisms in neuroinflammation. PMID:26500654

  9. Carmine hypersensitivity masquerading as azithromycin hypersensitivity.

    PubMed

    Greenhawt, Matthew; McMorris, Marc; Baldwin, James

    2009-01-01

    Macrolide hypersensitivity is a rarely reported event. However, carmine dye has become increasingly important as a provocative agent. We present a case of a woman with documented carmine hypersensitivity, who reported anaphylaxis 90 minutes after ingestion of a generic azithromycin. Our investigations revealed that this was an allergy to the carmine dye in the tablet's coating rather than to the antibiotic. Seven extracts were prepared including carmine dye, crushed dried female cochineal insects, crushed tablets of Zithromax (Pfizer Inc.) and generic azithromycin (Teva Pharmaceuticals), and the crushed colored coatings from both tablets. These were suspended in preservative-free normal saline, and then applied as a skin-prick test and read at 30 minutes. The skin-prick skin test results were 4+ to histamine and carmine dye, but negative to cochineal insect extract, Pfizer crushed tablets, and negative control. The patient was 1+ to the Teva crushed tablet, but was 4+ to the Teva brand coating and negative to the Pfizer brand coating, which did not contain carmine. The patient subsequently ingested Pfizer Zithromax without any sequelae. To our knowledge, this is the first reported case of carmine anaphylaxis attributed to carmine-containing medication. Careful history and skin-prick testing to the appropriate agents allowed elucidation of the subtlety of the true offending agent without unnecessary avoidance of the medication class. Patients with a carmine hypersensitivity should actively check with their pharmacy or prescribing physician to verify their medications are free of this offending agent. PMID:19331724

  10. TRPA1 Contributes to Cold Hypersensitivity

    PubMed Central

    Camino, Donato del; Murphy, Sarah; Heiry, Melissa; Barrett, Lee B.; Earley, Taryn J.; Cook, Colby A.; Petrus, Matt J.; Zhao, Michael; D'Amours, Marc; Deering, Nate; Brenner, Gary J.; Costigan, Michael; Hayward, Neil J.; Chong, Jayhong A.; Fanger, Christopher M.; Woolf, Clifford J.; Patapoutian, Ardem; Moran, Magdalene M.

    2010-01-01

    TRPA1 is a non-selective cation channel expressed by nociceptors. While it is widely accepted that TRPA1 serves as a broad irritancy receptor for a variety of reactive chemicals, its role in cold sensation remains controversial. Here, we demonstrate that mild cooling markedly increases agonist-evoked rat TRPA1 currents. In the absence of an agonist, even noxious cold only increases current amplitude slightly. These results suggest that TRPA1 is a key mediator of cold hypersensitivity in pathological conditions where reactive oxygen species and pro-inflammatory activators of the channel are present, but likely plays a comparatively minor role in acute cold sensation. Supporting this, cold hypersensitivity can be induced in wild-type but not Trpa1-/- mice by subcutaneous administration of a TRPA1 agonist. Furthermore, the selective TRPA1 antagonist HC-030031 reduces cold hypersensitivity in rodent models of inflammatory and neuropathic pain. PMID:21068322

  11. Structural basis of chronic beryllium disease: linking allergic hypersensitivity and autoimmunity.

    PubMed

    Clayton, Gina M; Wang, Yang; Crawford, Frances; Novikov, Andrey; Wimberly, Brian T; Kieft, Jeffrey S; Falta, Michael T; Bowerman, Natalie A; Marrack, Philippa; Fontenot, Andrew P; Dai, Shaodong; Kappler, John W

    2014-07-01

    T-cell-mediated hypersensitivity to metal cations is common in humans. How the T cell antigen receptor (TCR) recognizes these cations bound to a major histocompatibility complex (MHC) protein and self-peptide is unknown. Individuals carrying the MHCII allele, HLA-DP2, are at risk for chronic beryllium disease (CBD), a debilitating inflammatory lung condition caused by the reaction of CD4 T cells to inhaled beryllium. Here, we show that the T cell ligand is created when a Be(2+) cation becomes buried in an HLA-DP2/peptide complex, where it is coordinated by both MHC and peptide acidic amino acids. Surprisingly, the TCR does not interact with the Be(2+) itself, but rather with surface changes induced by the firmly bound Be(2+) and an accompanying Na(+) cation. Thus, CBD, by creating a new antigen by indirectly modifying the structure of preexisting self MHC-peptide complex, lies on the border between allergic hypersensitivity and autoimmunity.

  12. PEROXIDASE-MEDIATED MAMMALIAN CELL CYTOTOXICITY

    PubMed Central

    Edelson, Paul J.; Cohn, Zanvil A.

    1973-01-01

    Lactoperoxidase, in the presence of hydrogen peroxide and iodide is cytotoxic for human and mouse lymphoid cells, and human erythrocytes. Myeloperoxidase, in amounts equivalent to 1.5 x 106 neutrophils, readily replaces lactoperoxidase, and allows the substitution of the iodide ion by chloride. The myeloperoxidase-mediated reaction is rapid, and highly efficient, leading to 85–90% cell death in 90 min, as measured by 51chromium release and dye exclusion. The mixture of granulocytes. monocytes, and lymphocytes present in an inflammatory exudate, and the intimate cell-to-cell association characteristic of cytotoxic phenomena may provide the in vivo requirements for such a system. PMID:4717124

  13. Fetal hemoglobin in sickle cell anemia: examination of phylogenetically conserved sequences within the locus control region but outside the cores of hypersensitive sites 2 and 3.

    PubMed

    Figueiredo, M S; Steinberg, M H

    1997-08-01

    Regulatory elements linked to the beta-globin gene cluster modulates gamma-globin gene expression. The location of all of these elements and their mechanisms of action are still incompletely defined. Phylogenetically conserved DNA within the beta-globin gene cluster locus control region (LCR), but outside the core sequences of its hypersensitive sites (HS), were identified and we searched for any differences between HS 3 and HS 2, and HS 2 and HS 1, among patients with sickle cell anemia with different levels of Hb F who were homozygous for the common haplotypes. DNA was amplified with and without GC clamps, digested with restriction endonucleases, and examined by denaturing gradient gel electrophoresis (DGGE). We found limited fragment size diversity. However, the type of differences found and their distribution among haplotypes did not suggest that they represented distinctive changes that might explain the differential expression of the gamma-globin genes in sickle cell anemia.

  14. Topoisomerase II-Mediated DNA Damage Is Differently Repaired during the Cell Cycle by Non-Homologous End Joining and Homologous Recombination

    PubMed Central

    de Campos-Nebel, Marcelo; Larripa, Irene; González-Cid, Marcela

    2010-01-01

    Topoisomerase II (Top2) is a nuclear enzyme involved in several metabolic processes of DNA. Chemotherapy agents that poison Top2 are known to induce persistent protein-mediated DNA double strand breaks (DSB). In this report, by using knock down experiments, we demonstrated that Top2α was largely responsible for the induction of γH2AX and cytotoxicity by the Top2 poisons idarubicin and etoposide in normal human cells. As DSB resulting from Top2 poisons-mediated damage may be repaired by non-homologous end joining (NHEJ) or homologous recombination (HR), we aimed to analyze both DNA repair pathways. We found that DNA-PKcs was rapidly activated in human cells, as evidenced by autophosphorylation at serine 2056, following Top2-mediated DNA damage. The chemical inhibition of DNA-PKcs by wortmannin and vanillin resulted in an increased accumulation of DNA DSB, as evaluated by the comet assay. This was supported by a hypersensitive phenotype to Top2 poisons of Ku80- and DNA-PKcs- defective Chinese hamster cell lines. We also showed that Rad51 protein levels, Rad51 foci formation and sister chromatid exchanges were increased in human cells following Top2-mediated DNA damage. In support, BRCA2- and Rad51C- defective Chinese hamster cells displayed hypersensitivity to Top2 poisons. The analysis by immunofluorescence of the DNA DSB repair response in synchronized human cell cultures revealed activation of DNA-PKcs throughout the cell cycle and Rad51 foci formation in S and late S/G2 cells. Additionally, we found an increase of DNA-PKcs-mediated residual repair events, but not Rad51 residual foci, into micronucleated and apoptotic cells. Therefore, we conclude that in human cells both NHEJ and HR are required, with cell cycle stage specificity, for the repair of Top2-mediated reversible DNA damage. Moreover, NHEJ-mediated residual repair events are more frequently associated to irreversibly damaged cells. PMID:20824055

  15. Airway Inflammation and Hypersensitivity Induced by Chronic Smoking

    PubMed Central

    Kou, Yu Ru; Kwong, Kevin; Lee, Lu-Yuan

    2011-01-01

    Airway hypersensitivity, characterized by enhanced excitability of airway sensory nerves, is a prominent pathophysiological feature in patients with airway inflammatory diseases. Although the underlying pathogenic mechanism is not fully understood, chronic airway inflammation is believed to be primarily responsible. Cigarette smoking is known to cause chronic airway inflammation, accompanied by airway hyperresponsiveness. Experimental evidence indicates that enhanced excitability of vagal bronchopulmonary sensory nerves and increased tachykinin synthesis in these nerves resulting from chronic inflammation are important contributing factors to the airway hyperresponsiveness. Multiple inflammatory mediators released from various types of structural and inflammatory cells are involved in the smoking-induced airway inflammation, which is mainly regulated by redox-sensitive signaling pathways and transcription factors. Furthermore, recent studies have reported potent sensitizing and stimulatory effects of these inflammatory mediators such as prostanoids and reactive oxygen species on these sensory nerves. In summary, these studies using cigarette smoking as an experimental approach have identified certain potentially important cell signaling pathways and underlying mechanisms of the airway hypersensitivity induced by chronic airway inflammation. PMID:21397052

  16. Secretome identification of immune cell factors mediating metastatic cell homing

    PubMed Central

    Aguado, Brian A.; Wu, Jia J.; Azarin, Samira M.; Nanavati, Dhaval; Rao, Shreyas S.; Bushnell, Grace G.; Medicherla, Chaitanya B.; Shea, Lonnie D.

    2015-01-01

    Metastatic cell homing is a complex process mediated in part by diffusible factors secreted from immune cells found at a pre-metastatic niche. We report on connecting secretomics and TRanscriptional Activity CEll aRray (TRACER) data to identify functional paracrine interactions between immune cells and metastatic cells as novel mediators of homing. Metastatic breast cancer mouse models were used to generate a diseased splenocyte conditioned media (D-SCM) containing immune cell secreted factors. MDA-MB-231 metastatic cell activity including cell invasion, migration, transendothelial migration, and proliferation were increased in D-SCM relative to control media. Our D-SCM secretome analysis yielded 144 secreted factor candidates that contribute to increased metastatic cell activity. The functional mediators of homing were identified using MetaCore software to determine interactions between the immune cell secretome and the TRACER-identified active transcription factors within metastatic cells. Among the 5 candidate homing factors identified, haptoglobin was selected and validated in vitro and in vivo as a key mediator of homing. Our studies demonstrate a novel systems biology approach to identify functional signaling factors associated with a cellular phenotype, which provides an enabling tool that complements large-scale protein identification provided by proteomics. PMID:26634905

  17. Regulation of IgE-Mediated Food Allergy by IL-9 Producing Mucosal Mast Cells and Type 2 Innate Lymphoid Cells.

    PubMed

    Lee, Jee-Boong

    2016-08-01

    Due to the increasing prevalence and number of life-threatening cases, food allergy has emerged as a major health concern. The classic immune response seen during food allergy is allergen-specific IgE sensitization and hypersensitivity reactions to foods occur in the effector phase with often severe and deleterious outcomes. Recent research has advanced understanding of the immunological mechanisms occurring during the effector phase of allergic reactions to ingested food. Therefore, this review will not only cover the mucosal immune system of the gastrointestinal tract and the immunological mechanisms underlying IgE-mediated food allergy, but will also introduce cells recently identified to have a role in the hypersensitivity reaction to food allergens. These include IL-9 producing mucosal mast cells (MMC9s) and type 2 innate lymphoid cells (ILC2s). The involvement of these cell types in potentiating the type 2 immune response and developing the anaphylactic response to food allergens will be discussed. In addition, it has become apparent that there is a collaboration between these cells that contributes to an individual's susceptibility to IgE-mediated food allergy. PMID:27574500

  18. Regulation of IgE-Mediated Food Allergy by IL-9 Producing Mucosal Mast Cells and Type 2 Innate Lymphoid Cells

    PubMed Central

    2016-01-01

    Due to the increasing prevalence and number of life-threatening cases, food allergy has emerged as a major health concern. The classic immune response seen during food allergy is allergen-specific IgE sensitization and hypersensitivity reactions to foods occur in the effector phase with often severe and deleterious outcomes. Recent research has advanced understanding of the immunological mechanisms occurring during the effector phase of allergic reactions to ingested food. Therefore, this review will not only cover the mucosal immune system of the gastrointestinal tract and the immunological mechanisms underlying IgE-mediated food allergy, but will also introduce cells recently identified to have a role in the hypersensitivity reaction to food allergens. These include IL-9 producing mucosal mast cells (MMC9s) and type 2 innate lymphoid cells (ILC2s). The involvement of these cell types in potentiating the type 2 immune response and developing the anaphylactic response to food allergens will be discussed. In addition, it has become apparent that there is a collaboration between these cells that contributes to an individual's susceptibility to IgE-mediated food allergy. PMID:27574500

  19. Cell-mediated Protection in Influenza Infection

    PubMed Central

    Thomas, Paul G.; Keating, Rachael; Hulse-Post, Diane J.

    2006-01-01

    Current vaccine strategies against influenza focus on generating robust antibody responses. Because of the high degree of antigenic drift among circulating influenza strains over the course of a year, vaccine strains must be reformulated specifically for each influenza season. The time delay from isolating the pandemic strain to large-scale vaccine production would be detrimental in a pandemic situation. A vaccine approach based on cell-mediated immunity that avoids some of these drawbacks is discussed here. Specifically, cell-mediated responses typically focus on peptides from internal influenza proteins, which are far less susceptible to antigenic variation. We review the literature on the role of CD4+ and CD8+ T cell–mediated immunity in influenza infection and the available data on the role of these responses in protection from highly pathogenic influenza infection. We discuss the advantages of developing a vaccine based on cell-mediated immune responses toward highly pathogenic influenza virus and potential problems arising from immune pressure. PMID:16494717

  20. Retroviral transfer of a human beta-globin/delta-globin hybrid gene linked to beta locus control region hypersensitive site 2 aimed at the gene therapy of sickle cell disease.

    PubMed

    Takekoshi, K J; Oh, Y H; Westerman, K W; London, I M; Leboulch, P

    1995-03-28

    Human gamma-globin and delta-globin chains have been previously identified as strong inhibitors of the polymerization of hemoglobin S, in contrast to the beta-globin chain, which exerts only a moderate antisickling effect. However, gamma-globin and delta-globin are normally expressed at very low levels in adult erythroid cells, in contrast to beta-globin. We report the design of a beta-globin/delta-globin hybrid gene, beta/delta-sickle cell inhibitor 1 (beta/delta-SCI1) and its transduction by retrovirus-mediated gene transfer. The beta/delta-SCI1-encoding gene retains the overall structure of the human beta-globin gene, while incorporating specific amino acid residues from the delta chain previously found responsible for its enhanced antisickling properties. To achieve high expression levels of beta/delta-SCI1 in adult erythrocytes, the hybrid gene was placed under the transcriptional control of the human beta-globin promoter and the DNase I hypersensitive site 2 of the human beta locus control region. High-titer retroviruses were generated, and stable proviral transmission was achieved in infected cells. The mRNA expression levels of the beta/delta-SCI1 gene in infected, dimethyl sulfoxide-induced murine erythroleukemia cells approached 85% of the endogenous murine beta maj-globin mRNA, on a per gene basis, evidence that high gene expression levels were achieved in adult erythroid cells. Further evaluation of this strategy in transgenic animal models of sickle cell disease should assess its efficacy for the gene therapy of human patients.

  1. Cell-mediated destruction of cells grown on artificial capillaries.

    PubMed

    Zwilling, B S; Clayman, D A

    1978-11-01

    This investigation was designed to determine the conditions required to assess cell-mediated destruction of target L-cells grown on artificial capillaries. In control cultures that contained L-cells alone, solid nodules with a diameter of 1 mm as well as dense cellular growth could be visually observed by the 12th day of culture. Alloimmune spleen cells from both immunized and normal C57BL/10 mice were shown to be capable of destroying tritiated thymidine-labeled L-cells growing on artificial capillaries. The destruction of target cells grown as monolayers in capillary culture correlated well with monolayer cultures incubated in 16-mm plastic tissue culture wells. When target cells were grown in capillary culture for 5 days before the addition of effector cells, significant destruction by normal effector cells was not observed until the 15th day of culture whereas that mediated by immune cells was observed by the 7th day. The possible effects of cell-culturing conditions on the kinetics of cell-mediated destruction in capillary chambers are discussed.

  2. Neurodegenerative mechanisms in Alzheimer disease. A role for oxidative damage in amyloid beta protein precursor-mediated cell death.

    PubMed

    Sopher, B L; Fukuchi, K; Kavanagh, T J; Furlong, C E; Martin, G M

    1996-01-01

    We have established a stably transformed human neuroblastoma cell line (MC65) that conditionally expresses a C-terminal derivative of the amyloid beta protein precursor (beta PP) termed S beta C (a fusion protein composed of the amino-17 and carboxyl-99 residues of beta PP). Conditional expression of S beta C (mediated by the withdrawal of tetracycline from the culture medium) induces pronounced nuclear DNA fragmentation and cytotoxicity in this cell line. These effects are enhanced by hyperoxygen and suppressed by hypooxygen and antioxidants. This cell line is relatively insensitive to the extracellular application of amyloid beta 25-35, and coculture experiments suggest that this cytotoxicity is mediated by an intracellular process. These findings suggest that the overexpression of the C-terminal domain of beta PP can disrupt normal cellular processes in these cells in such a way as to induce a directed (deoxyribonuclease-mediated) mechanism of cell death. This process appears to be modulated and/or mediated by a reactive oxygen specie(s) (ROS). Consistent with a role for ROS in the process of S beta C-mediated toxicity, we have found that the MC65 cell line is hypersensitive to oxidative stress and that it is this sensitivity that appears (at least in part) to underlie its susceptibility to S beta C.

  3. Hypersensitivity to fluoroquinolones

    PubMed Central

    Fernández, Tahia D.; Ariza, Adriana; Palomares, Francisca; Montañez, María I.; Salas, María; Martín-Serrano, Angela; Fernández, Rubén; Ruiz, Arturo; Blanca, Miguel; Mayorga, Cristobalina; Torres, María J.

    2016-01-01

    Abstract Although fluoroquinolones (FQs) are generally well-tolerated antibiotics, increasing numbers of hypersensitivity reactions have been reported. These can be evaluated in vitro by basophil activation tests (BATs); however, sensitivity is not optimal. Many factors could influence sensitivity such as basophil activation markers. The objective of this study was to evaluate the influence of 2 different activations markers, CD63 and CD203c, on the sensitivity of BAT to FQ. We studied 17 patients with immediate allergic reactions to FQ. BAT was performed with moxifloxacin and ciprofloxacin using CD193 (CCR3) for basophil selection and CD203c or CD63 as activation markers. Stimulation with ciprofloxacin induced a significantly higher expression of CD63 in ciprofloxacin-allergic patients compared to moxifloxacin-allergic patients (P = 0.002). In patients allergic to moxifloxacin with anaphylactic shock, we have observed an increase in the percentage of cells that upregulate CD203c, whereas patients with anaphylaxis preferentially upregulate CD63. The best sensitivity–specificity was obtained using a cutoff of 3 and the culprit FQ, using CD203c for moxifloxacin-allergic patients (sensitivity = 36.4%; specificity = 94.4%), and CD63 for ciprofloxacin-allergic patients (sensitivity = 83.3%; specificity = 88.9%). A negative correlation was found between the upregulation of CD63 and CD203c and the time interval between the reaction occurrence and the performance of the test (Spearman r = −0.446; P < 0.001 for CD63 and Spearman r = −0.386; P < 0.001 for CD203c). The performance of BAT for FQ allergy must be optimized for each drug, taking into account possible differences in the stimulation mechanism that leads to the upregulation of different activation markers. PMID:27281069

  4. Mast Cell-Mediated Mechanisms of Nociception

    PubMed Central

    Aich, Anupam; Afrin, Lawrence B.; Gupta, Kalpna

    2015-01-01

    Mast cells are tissue-resident immune cells that release immuno-modulators, chemo-attractants, vasoactive compounds, neuropeptides and growth factors in response to allergens and pathogens constituting a first line of host defense. The neuroimmune interface of immune cells modulating synaptic responses has been of increasing interest, and mast cells have been proposed as key players in orchestrating inflammation-associated pain pathobiology due to their proximity to both vasculature and nerve fibers. Molecular underpinnings of mast cell-mediated pain can be disease-specific. Understanding such mechanisms is critical for developing disease-specific targeted therapeutics to improve analgesic outcomes. We review molecular mechanisms that may contribute to nociception in a disease-specific manner. PMID:26690128

  5. Redox polymer mediation for enzymatic biofuel cells

    NASA Astrophysics Data System (ADS)

    Gallaway, Joshua

    Mediated biocatalytic cathodes prepared from the oxygen-reducing enzyme laccase and redox-conducting osmium hydrogels were characterized for use as cathodes in enzymatic biofuel cells. A series of osmium-based redox polymers was synthesized with redox potentials spanning the range from 0.11 V to 0.85 V (SHE), and the resulting biocatalytic electrodes were modeled to determine reaction kinetic constants using the current response, measured osmium concentration, and measured apparent electron diffusion. As in solution-phase systems, the bimolecular rate constant for mediation was found to vary greatly with mediator potential---from 250 s-1M-1 when mediator and enzyme were close in potential to 9.4 x 10 4 s-1M-1 when this overpotential was large. Optimum mediator potential for a cell operating with a non-limiting platinum anode and having no mass transport limitation from bulk solution was found to be 0.66 V (SHE). Redox polymers were synthesized under different concentrations, producing osmium variation. An increase from 6.6% to 7.2% osmium increased current response from 1.2 to 2.1 mA/cm2 for a planar film in 40°C oxygen-saturated pH 4 buffer, rotating at 900 rpm. These results translated to high surface area electrodes, nearly doubling current density to 13 mA/cm2, the highest to date for such an electrode. The typical fungal laccase from Trametes versicolor was replaced by a bacterially-expressed small laccase from Streptomyces coelicolor, resulting in biocatalytic films that reduced oxygen at increased pH, with full functionality at pH 7, producing 1.5 mA/cm 2 in planar configuration. Current response was biphasic with pH, matching the activity profile of the free enzyme in solution. The mediated enzyme electrode system was modeled with respect to apparent electron diffusion, mediator concentration, and transport of oxygen from bulk solution, all of which are to some extent controlled by design. Each factor was found to limit performance in certain circumstances

  6. Sunscreens and T4N5 liposomes differ in their ability to protect against ultraviolet-induced sunburn cell formation, alterations of dendritic epidermal cells, and local suppression of contact hypersensitivity.

    PubMed

    Wolf, P; Cox, P; Yarosh, D B; Kripke, M L

    1995-02-01

    Exposure of skin to ultraviolet (UV) radiation can lead to diverse biologic effects, including inflammation, sunburn cell formation, alterations of cutaneous immune cells, and impaired induction of contact hypersensitivity responses. The molecular mechanisms of these UV-induced effects are not completely understood. We investigated the ability of sunscreens and liposomes containing the DNA excision repair enzyme T4 endonuclease V to prevent these effects of UV radiation. The use of T4N5 liposomes, which increase the repair of cyclobutyl pyrimidine dimers, provides an approach for assessing the role of DNA damage in the effects of UV radiation on the skin. Exposing C3H mice to 500 mJ/cm2 UVB radiation from FS40 sunlamps resulted in skin edema, sunburn cell formation, and morphologic alterations and decreased numbers of Langerhans cells and Thy-1+ dendritic epidermal T cells. In addition, the induction of contact hypersensitivity after application of 2,4-dinitrofluorobenzene on UV-irradiated skin was diminished by 80%. Applying sunscreens containing octyl-N-dimethyl-p-aminobenzoate, 2-ethylhexyl-p-methoxycinnamate, or benzophenone-3 before this dose of UV irradiation gave nearly complete protection against all of these effects of UV irradiation. In contrast, topical application of T4N5 liposomes after UV irradiation had no effect on UV-induced skin edema and only partially protected against sunburn cell formation and local suppression of contact hypersensitivity, although its ability to protect against alterations in dendritic immune cells was comparable to that of the sunscreens. These results suggest that DNA damage is involved in only some of the local effects of UV radiation on the skin. In addition, T4N5 liposomes may be a useful adjunct to sunscreens because they can reduce some of the deleterious effects of UV radiation on skin even after a sunburn has been initiated. PMID:7829886

  7. Electrosensibility and electromagnetic hypersensitivity.

    PubMed

    Leitgeb, Norbert; Schröttner, Jörg

    2003-09-01

    Electromagnetic sensibility, the ability to perceive electric and electromagnetic exposure, and electromagnetic hypersensitivity (EHS), developing health symptoms due to exposure to environmental electromagnetic fields, need to be distinguished. Increased electrosensibility is a necessary, however, not a sufficient condition for electromagnetic hypersensitivity. At an extended sample of the general population of 708 adults, including 349 men and 359 women aged between 17 and 60 years, electrosensibility was investigated and characterized by perception threshold and its standard deviation. By analyzing the probability distributions of the perception threshold of electric 50 Hz currents, evidence could be found for the existence of a subgroup of people with significantly increased electrosensibility (hypersensibility) who as a group could be differentiated from the general population. The presented data show that the variation of the electrosensibility among the general population is significantly larger than has yet been estimated by nonionizing radiation protection bodies, but much smaller than claimed by hypersensitivity self-aid groups. These quantitative results should contribute to a less emotional discussion of this problem. The investigation method presented, is capable of exclusion diagnostics for persons suffering from the hypersensitivity syndrome. PMID:12929157

  8. Nature of "memory" in T-cell-mediated antibacterial immunity: anamnestic production of mediator T cells.

    PubMed Central

    North, R J

    1975-01-01

    Mice that survived an immunizing infection with Listeria monocytogenes remained specifically resistant to lethal secondary infection for several months. This acquired, long-lived state of resistance was not dependent on activated macrophages that remained after the primary response. It depended, instead, on an acquired long-lived capacity on the part of immunized mice for generating mediator T cells faster and in larger numbers than normal mice. The number of mediator T cells generated in response to secondary infection was proportional to the level of infection. The results suggest that the accelerated production of mediator T cells that occurs in response to secondary infection represents the expression of a state of immunological T-cell memory. PMID:811558

  9. MicroRNA-mediated somatic cell reprogramming.

    PubMed

    Kuo, Chih-Hao; Ying, Shao-Yao

    2013-02-01

    Since the first report of induced pluripotent stem cells (iPSCs) using somatic cell nuclear transfer (SCNT), much focus has been placed on iPSCs due to their great therapeutic potential for diseases such as abnormal development, degenerative disorders, and even cancers. Subsequently, Takahashi and Yamanaka took a novel approach by using four defined transcription factors to generate iPSCs in mice and human fibroblast cells. Scientists have since been trying to refine or develop better approaches to reprogramming, either by using different combinations of transcription factors or delivery methods. However, recent reports showed that the microRNA expression pattern plays a crucial role in somatic cell reprogramming and ectopic introduction of embryonic stem cell-specific microRNAs revert cells back to an ESC-like state, although, the exact mechanism underlying this effect remains unclear. This review describes recent work that has focused on microRNA-mediated approaches to somatic cell reprogramming as well as some of the pros and cons to these approaches and a possible mechanism of action. Based on the pivotal role of microRNAs in embryogenesis and somatic cell reprogramming, studies in this area must continue in order to gain a better understanding of the role of microRNAs in stem cells regulation and activity. PMID:22961769

  10. A novel regulatory mechanism of naringenin through inhibition of T lymphocyte function in contact hypersensitivity suppression

    SciTech Connect

    Fang, Feng; Tang, Yijun; Gao, Zhe; Xu, Qiang

    2010-06-25

    Naringenin, a flavonoid in grapefruits and citrus fruits, has been reported to exhibit anti-inflammatory and anti-oxidative activities. Contact hypersensitivity (CHS) is a T cell-mediated immune reaction, and the factors released from macrophages also contribute to this response. Previous studies showed that naringenin suppressed CHS by inhibiting activation and migration of macrophages. However, little is known about naringenin's effects on T lymphocytes. Our study indicated that naringenin potently suppressed picryl chloride (PCl)-induced contact hypersensitivity by inhibiting the proliferation and activation of T lymphocytes. In vitro, both of the activated hapten-specific T cells and the T cells stimulated with anti-CD3/anti-CD28 showed growth arrest after naringenin treatment. Furthermore, naringenin reduced CD69 (the protein level) and cytokines such as IL-2, TNF-{alpha}, and IFN-{gamma} (the mRNA level) expressions which highly expressed by activated T cells. Meanwhile, naringenin also induced T cell apoptosis by upregulation of Bax, Bad, PARP, cleaved-caspase 3 and downregulation of phosphorylated Akt, Bcl-2. These findings suggest that, besides its anti-inflammatory activities in macrophages, naringenin also showed inhibitory effects on the activation and proliferation of T cells to alleviate symptoms of contact hypersensitivity.

  11. Oral immunotherapy induces IgG antibodies that act via FcγRIIb to suppress IgE-mediated hypersensitivity

    PubMed Central

    Burton, Oliver T.; Logsdon, Stephanie L.; Zhou, Joseph S.; Medina-Tamayo, Jaciel; Abdel-Gadir, Azza; Rivas, Magali Noval; Koleoglou, Kyle J.; Chatila, Talal A.; Schneider, Lynda C.; Rachid, Rima; Umetsu, Dale T.; Oettgen, Hans C.

    2014-01-01

    Background Food anaphylaxis is triggered by specific IgE antibodies. Paradoxically, some individuals with significant IgE levels can ingest allergenic foods without incident. Similarly, subjects completing oral immunotherapy (OIT) tolerate food challenges despite persistent high-titer food-specific IgE. Objective To test whether IgG antibodies induced by food immunotherapy prevent food-induced anaphylaxis, and whether this occurs via the inhibitory receptor FcγRIIb. Methods Food allergy-susceptible Il4raF709 mice were enterally sensitized to ovalbumin (OVA). Similarly sensitized IgE-deficient Il4raF709/IgE−/− mice, which can ingest OVA without anaphylaxis, were subjected to a high-dose enteral OVA desensitization protocol (OIT). Sera from both groups were tested for the ability to activate or inhibit bone marrow mast cells (BMMC) exposed to allergen, or to passively transfer allergy to naïve hosts. In parallel experiments, sera obtained from peanut allergic patients before and after undergoing OIT were interrogated for their ability to enhance or suppress peanut-induced activation in an indirect assay using basophils from non-allergic donors. Results Il4raF709 mice exhibited strong OVA-specific IgE responses. Their sera efficiently sensitized BMMC for activation by antigen challenge. Sera from Il4raF709/IgE−/− mice subjected to OVA OIT suppressed BMMC responses. This inhibition was IgG-mediated and FcγRIIb-dependent. Similarly, pre-OIT, but not post-OIT sera from patients efficiently sensitized basophils for peanut-induced activation. IgG antibodies in post-OIT sera suppressed basophil activation by pre-OIT sera. This inhibition was blocked by antibodies against FcγRII. Conclusion Food-specific IgG antibodies, such as those induced during OIT, inhibit IgE-mediated reactions. Strategies that favor IgG responses might prove useful in the management of food allergy. PMID:25042981

  12. Detection of delayed hypersensitivity reaction in rats by radioisotopic footpad assay with sodium deoxycholate extract and mitomycin-C-treated tumor cells.

    PubMed

    Yamada, Y; Mizushima, Y; Hosokawa, M; Kobayashi, H

    1978-08-01

    Immune response in WKA rats immunized with methylcholanthrene-induced KMT-17 tumor was measured by radioisotopic footpad assay. The assay was specific, quantitative, and objective compared with the ordinary method of measuring the thickness of footpads. The strongest footpad reaction was observed 24 hr after injection of the antigens. The reaction was transferred by lymphoid cells but not by serum. These results indicate that the footpad assay manifests delayed-type hypersensitivity to tumor antigens. In order to obtain more reliable antigen preparation for the footpad assay, antigens prepared by several methods were compared. Solubilized antigen extracted with sodium deoxycholate (DOC) showed the strongest reaction in the immunized host and weak reaction in the control non-immunized host. This marked difference between the immunized and control groups indicates that DOC-extracted antigen was better antigen than tumor cells treated with mitomycin-C (40 microgram/ml), formaldehyde solution (0.2%, 0.01%), X-irradiation (3,500, 10,000 rad), non-treated whole-cell antigen, crude membrane, cell homogenates, or antigens extracted by hypotonic sonication and 3M KCl method. The DOC-extracted antigen was well preserved at -20 degrees for 1 month. PMID:81787

  13. Gamma-irradiated scrub typhus immunogens: development of cell-mediated immunity after vaccination of inbred mice

    SciTech Connect

    Jerrells, T.R.; Palmer, B.A.; Osterman, J.V.

    1983-01-01

    Mice immunized with three injections of gamma-irradiated Karp strain of Rickettsia tsutsugamushi were evaluated for the presence of cell-mediated immunity by using delayed-type hypersensitivity, antigen-induced lymphocyte proliferation, and antigen-induced lymphokine production. These animals also were evaluated for levels of circulating antibody after immunization as well as for the presence of rickettsemia after intraperitoneal challenge with viable Karp rickettsiae. After immunization with irradiated Karp rickettsiae, a demonstrable cell-mediated immunity was present as evidenced by delayed-type hypersensitivity responsiveness, lymphocyte proliferation, and production of migration inhibition factor and interferon by immune spleen lymphocytes. Also, a reduction in circulating rickettsiae was seen in mice immunized with irradiated rickettsiae after challenge with 1,000 50% mouse lethal doses of viable, homologous rickettsiae. All responses except antibody titer and reduction of rickettsemia were similar to the responses noted in mice immunized with viable organisms. Antibody levels were lower in mice immunized with irradiated rickettsiae than in mice immunized with viable rickettsiae. Furthermore, mice that were immunized with viable rickettsiae demonstrated markedly lower levels of rickettsemia after intraperitoneal challenge compared with either mice immunized with irradiated rickettsiae or nonimmunized mice.

  14. Altered regulation of MHC class I genes in different tumor cell lines is reflected by distinct sets of DNase I hypersensitive sites.

    PubMed Central

    Maschek, U; Pülm, W; Hämmerling, G J

    1989-01-01

    MHC class I antigens play a crucial role in immunological functions, e.g. transplant and tumor rejection and antigen presentation. Whereas class I antigens are normally expressed on most adult tissues, albeit in varying amounts, embryonic as well as many tumor cells are characterized by the absence of major histocompatibility complex class I antigens on their cell surfaces. In this study the mechanism controlling the lack of class I expression was analyzed at the level of the chromatin structure. Five DNase I hypersensitive sites were determined at the H-2 D-locus of cell lines constitutively expressing class I genes. Two of them (DH1, located at the TATA box/transcription start site, and DH2, located at the enhancer/interferon response sequence) were absent in the fibrosarcoma IC9 in which expression of the silent Dk class I gene was not inducible. DH1 and DH2 remained absent even after fusion with class-I-positive cells. However, transfected Dk genes were expressed in IC9, and both DH1 and DH2, which were probably derived from the transfected gene, became detectable. In tumor cells expressing class I genes only after treatment with IFN-gamma (e.g. the lung carcinoma CMT64.5) or after in vitro differentiation (F9 embryonal carcinoma cells), DH1 and DH2 were already present before induction of class I expression. However, the intensity of the band indicative of DH2 was reduced in undifferentiated and differentiated F9 cells and in untreated CMT cells. Images PMID:2507317

  15. Radiation-induced lung injury: a hypersensitivity pneumonitis

    SciTech Connect

    Gibson, P.G.; Bryant, D.H.; Morgan, G.W.; Yeates, M.; Fernandez, V.; Penny, R.; Breit, S.N.

    1988-08-15

    Radiation pneumonitis occurs 6 to 12 weeks after thoracic irradiation, and is thought to be due to direct radiation-induced lung injury. Four patients who developed pneumonitis after unilateral thoracic irradiation for carcinoma of the breast were studied with bronchoalveolar lavage, gallium scan of the lung, and respiratory function tests. On the irradiated side of the chest, all four patients showed an increase in total cells recovered from the lavage fluid and a marked increase in the percentage of lymphocytes. When results for the unirradiated lung were compared with results for the irradiated lung, there was a comparable increase in total cells and percentage of lymphocytes. Gallium scans showed increases for both irradiated and unirradiated lungs. Prompt improvement was seen after corticosteroid therapy in all patients. The fact that abnormal findings occur equally in irradiated and unirradiated lung is inconsistent with simple direct radiation-induced injury and suggests an immunologically mediated mechanism such as a hypersensitivity pneumonitis.

  16. IL-4 abrogates TH17 cell-mediated inflammation by selective silencing of IL-23 in antigen-presenting cells

    PubMed Central

    Guenova, Emmanuella; Skabytska, Yuliya; Hoetzenecker, Wolfram; Weindl, Günther; Sauer, Karin; Tham, Manuela; Kim, Kyu-Won; Park, Ji-Hyeon; Seo, Ji Hae; Ignatova, Desislava; Cozzio, Antonio; Levesque, Mitchell P.; Volz, Thomas; Köberle, Martin; Kaesler, Susanne; Thomas, Peter; Mailhammer, Reinhard; Ghoreschi, Kamran; Schäkel, Knut; Amarov, Boyko; Eichner, Martin; Schaller, Martin; Clark, Rachael A.; Röcken, Martin; Biedermann, Tilo

    2015-01-01

    Interleukin 4 (IL-4) can suppress delayed-type hypersensitivity reactions (DTHRs), including organ-specific autoimmune diseases in mice and humans. Despite the broadly documented antiinflammatory effect of IL-4, the underlying mode of action remains incompletely understood, as IL-4 also promotes IL-12 production by dendritic cells (DCs) and IFN-γ–producing TH1 cells in vivo. Studying the impact of IL-4 on the polarization of human and mouse DCs, we found that IL-4 exerts opposing effects on the production of either IL-12 or IL-23. While promoting IL-12–producing capacity of DCs, IL-4 completely abrogates IL-23. Bone marrow chimeras proved that IL-4–mediated suppression of DTHRs relies on the signal transducer and activator of transcription 6 (STAT6)-dependent abrogation of IL-23 in antigen-presenting cells. Moreover, IL-4 therapy attenuated DTHRs by STAT6- and activating transcription factor 3 (ATF3)-dependent suppression of the IL-23/TH17 responses despite simultaneous enhancement of IL-12/TH1 responses. As IL-4 therapy also improves psoriasis in humans and suppresses IL-23/TH17 responses without blocking IL-12/TH1, selective IL-4–mediated IL-23/TH17 silencing is promising as treatment against harmful inflammation, while sparing the IL-12–dependent TH1 responses. PMID:25646481

  17. [Electromagnetic fields hypersensitivity].

    PubMed

    Sobiczewska, Elzbieta; Szmigielski, Stanisław

    2009-01-01

    The development of industry, particularly of new technologies in communication systems, gives rise to the number and diversty of electromagnetic field (EMF) sources in the environment. These sources, including power-frequent, radiofrequent and microwaves, make human life richer, safer and easier. But at the same time, there is growing concern about possible health risks connected with EMF exposure. An increasing number of persons have recently reported on a variety of health problems induced, in their opinion, by exposure to EMF. It is important to note that EMF levels to which these individuals are exposed are generally well below the recommended exposure limits and are certainly far below those known to produce any adverse effects. These persons call themselves "electromagnetic hypersensitivity individuals" And complain about experiencing various types of non-specific symptoms, including dermatological, neurological and vegetative. In the present paper, the problem of electromagnetic hypersensitivity phenomenon is discussed based on the recently published literature.

  18. Dentin Hypersensitivity and Oxalates

    PubMed Central

    Cunha-Cruz, J.; Stout, J.R.; Heaton, L.J.; Wataha, J.C.

    2011-01-01

    Treatment of dentin hypersensitivity with oxalates is common, but oxalate efficacy remains unclear. Our objective was to systematically review clinical trials reporting an oxalate treatment compared with no treatment or placebo with a dentin hypersensitivity outcome. Risk-of-bias assessment and data extraction were performed independently by two reviewers. Standardized mean differences (SMD) were estimated by random-effects meta-analysis. Of 677 unique citations, 12 studies with high risk-of-bias were included. The summary SMD for 3% monohydrogen-monopotassium oxalate (n = 8 studies) was -0.71 [95% Confidence Interval: -1.48, 0.06]. Other treatments, including 30% dipotassium oxalate (n = 1), 30% dipotassium oxalate plus 3% monohydrogen monopotassium oxalate (n = 3), 6% monohydrogen monopotassium oxalate (n = 1), 6.8% ferric oxalate (n = 1), and oxalate-containing resin (n = 1), also were not statistically significantly different from placebo treatments. With the possible exception of 3% monohydrogen monopotassium oxalate, available evidence currently does not support the recommendation of dentin hypersensitivity treatment with oxalates. PMID:21191127

  19. [Corneal ulcerative lesions in type-I immediate hypersensitivity].

    PubMed

    Giuri, S

    1998-01-01

    The vernal keratoconjunctivitis (KCV) is included within the category of the hypersensitiveness diseases, the immunopathological mechanism which causes the disease being represented by a type-I hypersensibility reaction. The mechanism which determines the appearance of the corneal lesions isn't entirely cleared up, but there are however some pathogenic links which have been already deciphered. The type I hypersensibility reaction is taking place within two stages: stage I the stage of the sensitizing contact and stage II the stage of the unleashing contact. During the first stage, the Langerhans cells take over and process the allergen, exhibiting on their surface only the antigenic part. The Langerhans cells interact with the T helper native cells (Tho), cells from which there will result the predominantly differentiated Th2 subtype. The Thz cells will activate, by means of the interleukines, the B cells (which produce the IgE), the mast cells and the eosinophilic cells. During the second stage, the allergen is coming into contact with the IgE specific antibodies, which are fastened on the mast cells membrane, generating the opening of their granules. The result of this evolution is represented by the unleash of vasoactive mediators, own enzymes, chemical mediators (among which there is also the eosinophilic chemotactic factor ECFA). The latter contributes to the infiltration of the epithelial and of the subepithelial tissue with eosinophilic cells. The major basic protein (PBM), one of the proteins released from the eosinophilic cells' big granules, plays a major pathogenic role in the production of the corneal ulcer, by means of its direct cytotoxic effect and also by means of inhibiting the migration of the epithelial corneal cells. The role of the mast cells and also the role of the neutrophile cells within the framework of the pathogenesis of the ulcer is disputable, because some specific enzymes tryptase, respectively elastase--have been found within the

  20. [Corneal ulcerative lesions in type-I immediate hypersensitivity].

    PubMed

    Giuri, S

    1998-01-01

    The vernal keratoconjunctivitis (KCV) is included within the category of the hypersensitiveness diseases, the immunopathological mechanism which causes the disease being represented by a type-I hypersensibility reaction. The mechanism which determines the appearance of the corneal lesions isn't entirely cleared up, but there are however some pathogenic links which have been already deciphered. The type I hypersensibility reaction is taking place within two stages: stage I the stage of the sensitizing contact and stage II the stage of the unleashing contact. During the first stage, the Langerhans cells take over and process the allergen, exhibiting on their surface only the antigenic part. The Langerhans cells interact with the T helper native cells (Tho), cells from which there will result the predominantly differentiated Th2 subtype. The Thz cells will activate, by means of the interleukines, the B cells (which produce the IgE), the mast cells and the eosinophilic cells. During the second stage, the allergen is coming into contact with the IgE specific antibodies, which are fastened on the mast cells membrane, generating the opening of their granules. The result of this evolution is represented by the unleash of vasoactive mediators, own enzymes, chemical mediators (among which there is also the eosinophilic chemotactic factor ECFA). The latter contributes to the infiltration of the epithelial and of the subepithelial tissue with eosinophilic cells. The major basic protein (PBM), one of the proteins released from the eosinophilic cells' big granules, plays a major pathogenic role in the production of the corneal ulcer, by means of its direct cytotoxic effect and also by means of inhibiting the migration of the epithelial corneal cells. The role of the mast cells and also the role of the neutrophile cells within the framework of the pathogenesis of the ulcer is disputable, because some specific enzymes tryptase, respectively elastase--have been found within the

  1. [Hypersensitivity to mosquito bite manifested as Skeeter síndrome].

    PubMed

    Pérez-Vanzzini, Rafael; González-Díaz, Sandra Nora; Arias-Cruz, Alfredo; Palma-Gómez, Samuel; Yong-Rodríguez, Adrián; Gutiérrez-Mujica, José Julio; García-Calderín, Diego; Ibarra, Jesús Arturo

    2015-01-01

    The reactions to mosquito bites are immunological reactions with involvement of IgE, IgG and T cells mediated hypersensitivity. These reactions are common and range from small local reactions, large local reactions to systemic allergic reactions. Skeeter syndrome is defined as a large local induced inflammatory reaction to mosquito bite and sometimes accompanied by systemic symptoms such as fever and vomiting. Diagnosis is based on clinical history and physical examination, supported by the identification of specific IgE by skin testing. Treatment includes prevention, antihistamines and steroids in some cases. Specific immunotherapy still requires further study. This paper reports two cases of patients with hypersensitivity reactions to mosquito bites, which were evaluated in our center presenting positive skin tests.

  2. Immunomodulatory activity of mefenamic acid in mice models of cell-mediated and humoral immunity

    PubMed Central

    Shabbir, Arham; Arshad, Hafiza Maida; Shahzad, Muhammad; Shamsi, Sadia; Ashraf, Muhammad Imran

    2016-01-01

    Objectives: Previously, different nonsteroidal anti-inflammatory drugs (NSAIDs) have been evaluated for their potential immunomodulatory activities. Mefenamic acid is a well-known NSAID and is used in the treatment of musculoskeletal disorders, inflammation, fever, and pain. To the best of our knowledge, promising data regarding the immunomodulatory activity of mefenamic acid is scarce. Current study investigates the immunomodulatory activity of mefenamic acid in different models of cell-mediated and humoral immunity. Materials and Methods: Immunomodulatory effects on cell-mediated immunity were evaluated using dinitrochlorobenzene-induced delayed type hypersensitivity (DTH) and cyclophosphamide-induce myelosuppression assays. While effects on humoral immunity were evaluated using hemagglutination assay and mice lethality test. Results: Hematological analysis showed that mefenamic acid significantly reduced white blood cell count, red blood cell (RBC) count, hemoglobin content, lymphocytes levels, and neutrophils levels in healthy mice as compared with control, suggesting the immunosuppressive activity of mefenamic acid. Treatment with mefenamic acid also significantly reduced all the hematological parameters in cyclophosphamide-induced neutropenic mice, as compared with positive control group. We found that treatment with mefenamic acid significantly suppressed DTH after 24 h, 48 h, and 72 h, as compared with positive control group. Mefenamic acid treated groups showed a significant reduction in antibody titer against sheep RBCs as compared to control group, similar to the effect of cyclophosphamide. We also found increased mice lethality rate in mefenamic acid treated groups, as compared with positive control group. Conclusions: The results provided basic information of immunosuppression of mefenamic acid on both cell-mediated and humoral immunity. PMID:27127320

  3. What we know about nonsteroidal anti-inflammatory drug hypersensitivity

    PubMed Central

    Pham, Duy Le; Kim, Ji-Hye; Trinh, Tu Hoang Kim; Park, Hae-Sim

    2016-01-01

    Nonsteroidal anti-inf lammatory drugs (NSAIDs) are widely prescribed for the treatment of inflammatory diseases, but their use is frequently related to hypersensitivity reactions. This review outlines our current knowledge of NSAID hypersensitivity (NHS) with regard to its pathogenic, molecular, and genetic mechanisms, as well as diagnosis and treatment. The presentation of NHS varies from a local (skin and/or airways) reaction to systemic reactions, including anaphylaxis. At the molecular level, NHS reactions can be classified as cross-reactive (mediated by cyclooxygenase inhibition) or selective (specific activation of immunoglobulin E antibodies or T cells). Genetic polymorphisms and epigenetic factors have been shown to be closely associated with NHS, and may be useful as predictive markers. To diagnose NHS, inhalation or oral challenge tests are applied, with the exclusion of any cross-reactive NSAIDs. For patients diagnosed with NHS, absolute avoidance of NSAIDs/aspirin is essential, and pharmacological treatment, including biologics, is often used to control their respiratory and cutaneous symptoms. Finally, desensitization is recommended only for selected patients with NHS. However, further research is required to develop new diagnostic methods and more effective treatments against NHS. PMID:27030979

  4. [Nonallergic hypersensitivity to environmental factors].

    PubMed

    Rakhmanin, Iu A; Fedoseeva, V N; Makovetskaia, A K; Fedoskova, T G

    2013-01-01

    The prevalence and severity of manifestations of non-allergic hypersensitivity to chemical environmental factors pose the question about the need to study the mechanisms of its formation in population. It should be borne in mind that, in the absence of immunological mechanisms of formation of the mentioned state, the term "chemical sensitization" must be replaced by the term "non-allergic hypersensitivity." The investigation of this problem should permit to reduce the risk of formation of different types of hypersensitivity in population.

  5. Asymmetrical hypersensitivity to bovine collagen.

    PubMed

    Somerville, P; Wray, R C

    1993-05-01

    We report a unique patient with true asymmetrical hypersensitivity to bovine collagen. Hypersensitivity is the development of an inflammatory response at a treatment site after a negative skin test. She developed an inflammatory response in only one of two simultaneously injected sites. About 1.5% of patients with a negative skin test have a hypersensitivity reaction consisting of firmness, erythema, and swelling. The signs and symptoms generally resolve spontaneously in a few months.

  6. Histamine in the locus coeruleus promotes descending noradrenergic inhibition of neuropathic hypersensitivity.

    PubMed

    Wei, Hong; Jin, Cong-Yu; Viisanen, Hanna; You, Hao-Jun; Pertovaara, Antti

    2014-12-01

    Among brain structures receiving efferent projections from the histaminergic tuberomammillary nucleus is the pontine locus coeruleus (LC) involved in descending noradrenergic control of pain. Here we studied whether histamine in the LC is involved in descending regulation of neuropathic hypersensitivity. Peripheral neuropathy was induced by unilateral spinal nerve ligation in the rat with a chronic intracerebral and intrathecal catheter for drug administrations. Mechanical hypersensitivity in the injured limb was assessed by monofilaments. Heat nociception was assessed by determining radiant heat-induced paw flick. Histamine in the LC produced a dose-related (1-10μg) mechanical antihypersensitivity effect (maximum effect at 15min and duration of effect 30min), without influence on heat nociception. Pretreatment of LC with zolantidine (histamine H2 receptor antagonist), but not with pyrilamine (histamine H1 receptor antagonist), and spinal administration of atipamezole (an α2-adrenoceptor antagonist), prazosine (an α1-adrenoceptor antagonist) or bicuculline (a GABAA receptor antagonist) attenuated the antihypersensitivity effect of histamine. The histamine-induced antihypersensitivity effect was also reduced by pretreatment of LC with fadolmidine, an α2-adrenoceptor agonist inducing autoinhibition of noradrenergic cell bodies. Zolantidine or pyrilamine alone in the LC failed to influence pain behavior, while A-960656 (histamine H3 receptor antagonist) suppressed hypersensitivity. A plausible explanation for these findings is that histamine, due to excitatory action mediated by the histamine H2 receptor on noradrenergic cell bodies, promotes descending spinal α1/2-adrenoceptor-mediated inhibition of neuropathic hypersensitivity. Blocking the autoinhibitory histamine H3 receptor on histaminergic nerve terminals in the LC facilitates release of histamine and thereby, increases descending noradrenergic pain inhibition.

  7. Effect of treatment with cyclophosphamide in low doses upon the onset of delayed type hypersensitivity in mice chronically infected with Trypanosoma cruzi: involvement of heart interstitial dendritic cells.

    PubMed

    Thé, Torriceli Souza; Portella, Renata Siqueira; Guerreiro, Marcos Lázaro; Andrade, Sonia Gumes

    2013-09-01

    Acute infection with Trypanosoma cruzi results in intense myocarditis, which progresses to a chronic, asymptomatic indeterminate form. The evolution toward this chronic cardiac form occurs in approximately 30% of all cases of T. cruzi infection. Suppression of delayed type hypersensitivity (DTH) has been proposed as a potential explanation of the indeterminate form. We investigated the effect of cyclophosphamide (CYCL) treatment on the regulatory mechanism of DTH and the participation of heart interstitial dendritic cells (IDCs) in this process using BALB/c mice chronically infected with T. cruzi. One group was treated with CYCL (20 mg/kg body weight) for one month. A DTH skin test was performed by intradermal injection of T. cruzi antigen (3 mg/mL) in the hind-footpad and measured the skin thickness after 24 h, 48 h and 72 h. The skin test revealed increased thickness in antigen-injected footpads, which was more evident in the mice treated with CYCL than in those mice that did not receive treatment. The thickened regions were characterised by perivascular infiltrates and areas of necrosis. Intense lesions of the myocardium were present in three/16 cases and included large areas of necrosis. Morphometric evaluation of lymphocytes showed a predominance of TCD8 cells. Heart IDCs were immunolabelled with specific antibodies (CD11b and CD11c) and T. cruzi antigens were detected using a specific anti-T. cruzi antibody. Identification of T. cruzi antigens, sequestered in these cells using specific anti-T. cruzi antibodies was done, showing a significant increase in the number of these cells in treated mice. These results indicate that IDCs participate in the regulatory mechanisms of DTH response to T. cruzi infection.

  8. Laryngeal hypersensitivity in chronic cough.

    PubMed

    Hull, J H; Menon, A

    2015-12-01

    Patients with chronic cough often report symptoms arising in the throat, in response to non-specific stimuli. Accordingly, the concept of a 'hypersensitivity' of the larynx in chronic cough has evolved over the past ten years. Patients with cough and laryngeal hypersensitivity frequently report features that overlap other laryngeal dysfunction syndromes, including a tendency for the vocal cords to inappropriately adduct. The mechanisms underlying laryngeal hypersensitivity in chronic cough are currently unclear, however recent studies provide new clinical and physiological techniques to aid detection and monitoring of laryngeal hypersensitivity. This review provides an overview of the current state of knowledge in this field.

  9. Anticonvulsant hypersensitivity syndrome.

    PubMed

    Morkunas, A R; Miller, M B

    1997-10-01

    Anticonvulsant hypersensitivity syndrome (AHS) is an uncommon but potentially fatal adverse effect that can occur from exposure to phenytoin, carbamazepine, or phenobarbital. It has diverse clinical features and a variable presentation which results in a delay in making the diagnosis. The syndrome commonly begins within 3 weeks after initiation of an anticonvulsant. Patients typically present with a constellation of fever, usually followed by the development of a rash of variable severity and type, and lymphadenopathy. In patients presenting with these features, the clinician should have a high index of suspicion for AHS. PMID:9330838

  10. Chronic hypersensitivity pneumonitis

    PubMed Central

    Pereira, Carlos AC; Gimenez, Andréa; Kuranishi, Lilian; Storrer, Karin

    2016-01-01

    Hypersensitivity pneumonitis (HSP) is a common interstitial lung disease resulting from inhalation of a large variety of antigens by susceptible individuals. The disease is best classified as acute and chronic. Chronic HSP can be fibrosing or not. Fibrotic HSP has a large differential diagnosis and has a worse prognosis. The most common etiologies for HSP are reviewed. Diagnostic criteria are proposed for both chronic forms based on exposure, lung auscultation, lung function tests, HRCT findings, bronchoalveolar lavage, and biopsies. Treatment options are limited, but lung transplantation results in greater survival in comparison to idiopathic pulmonary fibrosis. Randomized trials with new antifibrotic agents are necessary. PMID:27703382

  11. Anoikis Mediators in Oral Squamous Cell Carcinoma

    PubMed Central

    Bunek, Julius; Kamarajan, Pachiyappan; Kapila, Yvonne L.

    2010-01-01

    Anoikis—apoptotic cell death triggered by loss of extracellular matrix (ECM) contacts— is dysregulated in many chronic debilitating and fatal diseases. Mechanisms rendering tumor cells resistant to anoikis, although not completely understood, possess significant therapeutic promise. In death receptor-mediated anoikis mechanisms, FAK and RIP dissociate, leading to association of RIP with Fas, formation of the death-inducing signaling complex (DISC), activation of caspase-3, and propagation of anoikis. In contrast, anoikis resistance is accomplished through constitutive activation of survival pathways that include integrin-dependent activation of focal adhesion kinase (FAK) and extracellular-signal-regulated kinase (ERK). In addition, FAK and receptor-interacting protein (RIP) association confers anoikis resistance by inhibiting the association of RIP with Fas and formation of the death signaling complex, which allows cells to escape anoikis. Up-regulation of CD44 also contributes to survival signals and promotes anoikis resistance. This review will focus on the roles of death receptors, pro-survival pathways, and the molecular players involved in anoikis escalation and resistance in OSCC. PMID:21114588

  12. Stachybotrys chartarum-Induced Hypersensitivity Pneumonitis Is TLR9 Dependent

    PubMed Central

    Bhan, Urvashi; Newstead, Michael J.; Zeng, Xianying; Ballinger, Megan N.; Standiford, Louis R.; Standiford, Theodore J.

    2011-01-01

    Hypersensitivity pneumonitis (HP), an inflammatory lung disease, develops after repeated exposure to inhaled particulate antigen and is characterized by a vigorous T helper type 1-mediated immune response, resulting in the release of IL-12 and interferon (IFN)-γ. These T helper type 1 cytokines may participate in the pathogenesis of HP. Stachybotrys chartarum (SC) is a dimorphic fungus implicated in a number of respiratory illnesses, including HP. Here, we have developed a murine model of SC-induced HP that reproduces pathology observed in human HP and hypothesized that toll receptor-like 9 (TLR9)-mediated dendritic cell responses are required for the generation of granulomatous inflammation induced by inhaled SC. Mice sensitized and challenged with 106 SC spores develop granulomatous inflammation with multinucleate giant cells, accompanied by increased accumulation of neutrophils and CD4+ and CD8+ T cells. SC sensitization and challenge resulted in robust pulmonary expression of tumor necrosis factor-α, IL-12, and IFN-γ. SC-mediated granulomatous inflammation required IFN-γ and was TLR9 dependent, because TLR9−/− mice displayed reduced peribronchial inflammation, decreased accumulation and/or activation of polymorphonuclear (PMN) and CD4+ and CD8+ T cells, and reduced lung expression of type 1 cytokines and chemokines. T-cell production of IFN-γ was IL-12 dependent. Our studies suggest that TLR9 is critical for dendritic cell-mediated development of a type 1 granulomatous inflammation in the lung in response to SC. PMID:21982832

  13. Hypersensitivity of prediabetic JCR:LA-cp rats to fine airborne combustion particle-induced direct and noradrenergic-mediated vascular contraction.

    PubMed

    Proctor, Spencer D; Dreher, Kevin L; Kelly, Sandra E; Russell, James C

    2006-04-01

    Particulate matter with mean aerodynamic diameter < or =2.5 microm (PM(2.5)), from diesel exhaust, coal or residual oil burning, and from industrial plants, is a significant component of airborne pollution. Type 2 diabetes is associated with enhanced risk of adverse cardiovascular events following exposure to PM(2.5). Particle properties, sources, and pathophysiological mechanisms responsible are unknown. We studied effects of residual oil fly ash (ROFA) from a large U.S. powerplant on vascular function in a prediabetic, hyperinsulinemic model, the JCR:LA-cp rat. Residual oil fly ash leachate (ROFA-L) was studied using aortic rings from young-adult, obese, insulin-resistant rats and lean normal rats in vitro. Contractile response to phenylephrine and relaxant response to acetylcholine were determined in the presence and absence of L-NAME (N(G)-nitro-L-arginine methyl ester). In a separate series of studies, the direct contractile effects of ROFA-L on repeated exposure were determined. ROFA-L (12.5 microg ml(-1)) increased phenylephrine-mediated contraction in obese (p < 0.05), but not in lean rat aortae, with the effect being exacerbated by L-NAME, and it reduced acetylcholine-mediated relaxation of both obese and lean aortae (p < 0.0001). Initial exposure of aortae to ROFA-L caused a small contractile response (<0.05 g), which was markedly greater on second exposure in the obese (approximately 0.6 g, p < 0.0001) aortae but marginal in lean (approximately 0.1 g) aortae. Our data demonstrate that bioavailable constituents of oil combustion particles enhance noradrenergic-mediated vascular contraction, impair endothelium-mediated relaxation, and induce direct vasocontraction in prediabetic rats. These observations provide the first direct evidence of the causal properties of PM(2.5) and identify the pathophysiological role of the early prediabetic state in susceptibility to environmentally induced cardiovascular disease. These are important implications for public

  14. Management of patients with nonaspirin-exacerbated respiratory disease aspirin hypersensitivity reactions.

    PubMed

    Saff, Rebecca R; Banerji, Aleena

    2015-01-01

    Because of widespread use, nonsteroidal anti-inflammatory drugs (NSAIDs) are the second most common cause of all adverse drug reactions, with hypersensitivity reported in ∼1% of the population. NSAID hypersensitivity can be categorized into five types by the underlying disease, symptoms of reaction, and timing of reaction. These include rhinitis and asthma induced by NSAIDs (also known as aspirin-exacerbated respiratory disease), NSAID-exacerbated cutaneous disease (NECD), urticaria or angioedema induced by multiple NSAIDs, single NSAID-induced reactions, and delayed NSAID reactions. NECD occurs in one-third of patients with chronic urticaria who develop an exacerbation of their urticaria, sometimes with angioedema, typically beginning 30-90 minutes after ingestion of NSAIDs that inhibit cyclooxygenase (COX)-1. In urticaria or angioedema induced by multiple NSAIDs, patients without underlying disease develop urticaria or angioedema 30-90 minutes after ingestion of COX-1-inhibiting NSAIDs including aspirin. Single NSAID-induced reactions are immediate and specific to a single NSAID and are thought to occur because of an IgE-mediated reaction against a specific epitope of the NSAID. Delayed NSAID reactions occur days to weeks after initiating an NSAID. These are T-cell mediated and not amenable to desensitization or rechallenge. Classifying the type of NSAID hypersensitivity is important because many patients with a prior history of urticaria or angioedema induced by multiple NSAIDs will often tolerate aspirin test dose. This would allow the use of an aspirin for primary or secondary prevention in patients with coronary artery disease despite a presumed history of NSAID hypersensitivity.

  15. Pathogenesis and diagnosis of delayed-type drug hypersensitivity reactions, from bedside to bench and back.

    PubMed

    Schrijvers, Rik; Gilissen, Liesbeth; Chiriac, Anca Mirela; Demoly, Pascal

    2015-01-01

    Drug hypersensitivity reactions (DHR) have been present since the advent of drugs. In particular T-cell mediated delayed-type hypersensitivity reactions represent a heterogeneous clinical entity with a diverse pathogenesis and result in a considerable burden of morbidity and mortality not only driven by the reactions themselves but also by the use of alternatives which are sometimes less effective or even more dangerous. Diagnostic procedures rely on clinical history, skin testing and potential provocation testing, whereas validated in vitro diagnostic procedures are still lacking for most of them. Recent work in the field of pharmacogenomics combined with basic scientific research has provided insights in the pathogenesis of abacavir and carbamazepine hypersensitivities linked with certain human leucocyte antigen risk alleles. Nevertheless, important scientific questions on how other DHR arise and how host-drug interactions occur, remain unanswered. Recent work indicates an intricate relation between host, drug and pathogens in severe cutaneous and systemic reactions and provides more insights in the role of regulatory T-cells and viral reactivation in these reactions. In this review we focus on type IV delayed-type DHR, and address recent advances in the pathogenesis, pharmacogenomics, and diagnosis of these reactions with an emphasis on the understandings arising from basic research.

  16. Hypersensitivity of Primordial Germ Cells to Compromised Replication-Associated DNA Repair Involves ATM-p53-p21 Signaling

    PubMed Central

    Zeng, Ruizhu; Southard, Teresa L.; Shima, Naoko; Schimenti, John C.

    2014-01-01

    Genome maintenance in germ cells is critical for fertility and the stable propagation of species. While mechanisms of meiotic DNA repair and chromosome behavior are well-characterized, the same is not true for primordial germ cells (PGCs), which arise and propagate during very early stages of mammalian development. Fanconi anemia (FA), a genomic instability syndrome that includes hypogonadism and testicular failure phenotypes, is caused by mutations in genes encoding a complex of proteins involved in repair of DNA lesions associated with DNA replication. The signaling mechanisms underlying hypogonadism and testicular failure in FA patients or mouse models are unknown. We conducted genetic studies to show that hypogonadism of Fancm mutant mice is a result of reduced proliferation, but not apoptosis, of PGCs, resulting in reduced germ cells in neonates of both sexes. Progressive loss of germ cells in adult males also occurs, overlaid with an elevated level of meiotic DNA damage. Genetic studies indicated that ATM-p53-p21 signaling is partially responsible for the germ cell deficiency. PMID:25010009

  17. High Glutathione and Glutathione Peroxidase-2 Levels Mediate Cell-Type-Specific DNA Damage Protection in Human Induced Pluripotent Stem Cells

    PubMed Central

    Dannenmann, Benjamin; Lehle, Simon; Hildebrand, Dominic G.; Kübler, Ayline; Grondona, Paula; Schmid, Vera; Holzer, Katharina; Fröschl, Mirjam; Essmann, Frank; Rothfuss, Oliver; Schulze-Osthoff, Klaus

    2015-01-01

    Summary Pluripotent stem cells must strictly maintain genomic integrity to prevent transmission of mutations. In human induced pluripotent stem cells (iPSCs), we found that genome surveillance is achieved via two ways, namely, a hypersensitivity to apoptosis and a very low accumulation of DNA lesions. The low apoptosis threshold was mediated by constitutive p53 expression and a marked upregulation of proapoptotic p53 target genes of the BCL-2 family, ensuring the efficient iPSC removal upon genotoxic insults. Intriguingly, despite the elevated apoptosis sensitivity, both mitochondrial and nuclear DNA lesions induced by genotoxins were less frequent in iPSCs compared to fibroblasts. Gene profiling identified that mRNA expression of several antioxidant proteins was considerably upregulated in iPSCs. Knockdown of glutathione peroxidase-2 and depletion of glutathione impaired protection against DNA lesions. Thus, iPSCs ensure genomic integrity through enhanced apoptosis induction and increased antioxidant defense, contributing to protection against DNA damage. PMID:25937369

  18. Optimization of cell-wall skeleton derived from Mycobacterium bovis BCG Tokyo 172 (SMP-105) emulsion in delayed-type hypersensitivity and antitumor models.

    PubMed

    Miyauchi, M; Murata, M; Fukushima, A; Sato, T; Nakagawa, M; Fujii, T; Koseki, N; Chiba, N; Kashiwazaki, Y

    2012-08-01

    Cell-wall skeleton prepared from Mycobacterium bovis BCG (BCG-CWS) is known as a potent adjuvant and has been shown to possess antitumor activity in many non-clinical and clinical studies. As there are no approved BCG-CWS formulations for cancer therapy, we investigated the potential for cancer immunotherapy of SMP-105, our originally produced BCG-CWS. For optimizing SMP-105 emulsion, we compared the effects of drakeoland squalane-based SMP-105 emulsions on IFN-γ production in rats and evaluated their ability to induce skin reaction in guinea pigs. Both emulsions had the same activity in both experiments. We selected squalane as base material and produced two types of squalane-based formulations (vialed emulsion and pumped emulsion) that can easily be prepared as oil-in-water emulsions. Although the vialed emulsion showed the same pattern of distribution as a usual homogenized emulsion, the pumped emulsion showed more uniform distribution than the other two emulsions. Whereas both emulsions enhanced strong delayed type hypersensitivity (DTH) reaction in a mouse model, the pumped emulsion induced slightly smaller edema. Data on oil droplet size distribution suggest that few micrometer oil droplet size might be appropriate for oil-in-water microemulsion of SMP-105. The antitumor potency of SMP-105 emulsion was stronger than that of some of the launched toll-like receptor (TLR) agonists (Aldara cream, Picibanil, and Immunobladder). Aldara and Picibanil showed limited antitumor effectiveness, while Immunobladder had almost the same effect as SMP-105 at the highest dose, but needed about 10 times the amount of SMP-105. These findings first indicate that SMP-105 has great potential in cancer immunotherapy.

  19. Proteasome Dysfunction Mediates High Glucose-Induced Apoptosis in Rodent Beta Cells and Human Islets

    PubMed Central

    Broca, Christophe; Varin, Elodie; Armanet, Mathieu; Tourrel-Cuzin, Cécile; Bosco, Domenico; Dalle, Stéphane; Wojtusciszyn, Anne

    2014-01-01

    The ubiquitin/proteasome system (UPS), a major cellular protein degradation machinery, plays key roles in the regulation of many cell functions. Glucotoxicity mediated by chronic hyperglycaemia is detrimental to the function and survival of pancreatic beta cells. The aim of our study was to determine whether proteasome dysfunction could be involved in beta cell apoptosis in glucotoxic conditions, and to evaluate whether such a dysfunction might be pharmacologically corrected. Therefore, UPS activity was measured in GK rats islets, INS-1E beta cells or human islets after high glucose and/or UPS inhibitor exposure. Immunoblotting was used to quantify polyubiquitinated proteins, endoplasmic reticulum (ER) stress through CHOP expression, and apoptosis through the cleavage of PARP and caspase-3, whereas total cell death was detected through histone-associated DNA fragments measurement. In vitro, we found that chronic exposure of INS-1E cells to high glucose concentrations significantly decreases the three proteasome activities by 20% and leads to caspase-3-dependent apoptosis. We showed that pharmacological blockade of UPS activity by 20% leads to apoptosis in a same way. Indeed, ER stress was involved in both conditions. These results were confirmed in human islets, and proteasome activities were also decreased in hyperglycemic GK rats islets. Moreover, we observed that a high glucose treatment hypersensitized beta cells to the apoptotic effect of proteasome inhibitors. Noteworthily, the decreased proteasome activity can be corrected with Exendin-4, which also protected against glucotoxicity-induced apoptosis. Taken together, our findings reveal an important role of proteasome activity in high glucose-induced beta cell apoptosis, potentially linking ER stress and glucotoxicity. These proteasome dysfunctions can be reversed by a GLP-1 analog. Thus, UPS may be a potent target to treat deleterious metabolic conditions leading to type 2 diabetes. PMID:24642635

  20. STUDIES ON HYPERSENSITIVITY

    PubMed Central

    Gell, P. G. H.; Benacerraf, B.

    1961-01-01

    In earlier observations with the picryl system, it was concluded that contact sensitivity was a form of delayed (cellular) hypersensitivity to conjugates of sensitizer with autologous proteins indistinguishable in its immunological mechanism from other classical forms of delayed hypersensitivity to proteins. This conclusion has been confirmed and extended with the picryl and chlorbenzoyl chloride systems. 1. It is shown that to induce a state of contact sensitivity, the minimal necessary amounts of hapten are of the same order of magnitude, whether this hapten is conjugated with protein or the free reactive chemical itself. From this, it is evident that contamination of conjugates with small amounts of unreacted sensitizer plays no part in the induction of contact reactivity by the conjugate. With the dinitrophenyl system, no contact sensitivity could be induced by the conjugates used; possible reasons for this discrepancy are discussed. 2. Animals sensitized to contact by homologous conjugate can be completely desensitized by injections of such a conjugate in large amount; a similar injection schedule has no effect on the contact sensitivity of animals sensitized with the free reactive sensitizer. 3. The capacity of heterologous (ovalbumin) conjugates to evoke anti-hapten antibodies is shown to be greater than that of homologous (guinea pig seralbumin) conjugates: the reverse is true of their capacity to induce delayed reactivity. 4. Evidence is brought forward to suggest that in animals sensitized with homologous albumin conjugates, the specificity of the delayed reaction involves more than the hapten alone, even though the carrier protein is non-antigenic on its own. The contrast with the apparent lesser specificity of the antibodies later produced is discussed. PMID:13704282

  1. TIM-1 glycoprotein binds the adhesion receptor P-selectin and mediates T cell trafficking during inflammation and autoimmunity.

    PubMed

    Angiari, Stefano; Donnarumma, Tiziano; Rossi, Barbara; Dusi, Silvia; Pietronigro, Enrica; Zenaro, Elena; Della Bianca, Vittorina; Toffali, Lara; Piacentino, Gennj; Budui, Simona; Rennert, Paul; Xiao, Sheng; Laudanna, Carlo; Casasnovas, Jose M; Kuchroo, Vijay K; Constantin, Gabriela

    2014-04-17

    Selectins play a central role in leukocyte trafficking by mediating tethering and rolling on vascular surfaces. Here we have reported that T cell immunoglobulin and mucin domain 1 (TIM-1) is a P-selectin ligand. We have shown that human and murine TIM-1 binds to P-selectin, and that TIM-1 mediates tethering and rolling of T helper 1 (Th1) and Th17, but not Th2 and regulatory T cells on P-selectin. Th1 and Th17 cells lacking the TIM-1 mucin domain showed reduced rolling in thrombin-activated mesenteric venules and inflamed brain microcirculation. Inhibition of TIM-1 had no effect on naive T cell homing, but it reduced T cell recruitment in a skin hypersensitivity model and blocked experimental autoimmune encephalomyelitis. Uniquely, the TIM-1 immunoglobulin variable domain was also required for P-selectin binding. Our data demonstrate that TIM-1 is a major P-selectin ligand with a specialized role in T cell trafficking during inflammatory responses and the induction of autoimmune disease.

  2. TIM-1 glycoprotein binds the adhesion receptor P-selectin and mediates T cell trafficking during inflammation and autoimmunity.

    PubMed

    Angiari, Stefano; Donnarumma, Tiziano; Rossi, Barbara; Dusi, Silvia; Pietronigro, Enrica; Zenaro, Elena; Della Bianca, Vittorina; Toffali, Lara; Piacentino, Gennj; Budui, Simona; Rennert, Paul; Xiao, Sheng; Laudanna, Carlo; Casasnovas, Jose M; Kuchroo, Vijay K; Constantin, Gabriela

    2014-04-17

    Selectins play a central role in leukocyte trafficking by mediating tethering and rolling on vascular surfaces. Here we have reported that T cell immunoglobulin and mucin domain 1 (TIM-1) is a P-selectin ligand. We have shown that human and murine TIM-1 binds to P-selectin, and that TIM-1 mediates tethering and rolling of T helper 1 (Th1) and Th17, but not Th2 and regulatory T cells on P-selectin. Th1 and Th17 cells lacking the TIM-1 mucin domain showed reduced rolling in thrombin-activated mesenteric venules and inflamed brain microcirculation. Inhibition of TIM-1 had no effect on naive T cell homing, but it reduced T cell recruitment in a skin hypersensitivity model and blocked experimental autoimmune encephalomyelitis. Uniquely, the TIM-1 immunoglobulin variable domain was also required for P-selectin binding. Our data demonstrate that TIM-1 is a major P-selectin ligand with a specialized role in T cell trafficking during inflammatory responses and the induction of autoimmune disease. PMID:24703780

  3. TIM-1 glycoprotein binds the adhesion receptor P-selectin and mediates T cell trafficking during inflammation and autoimmunity

    PubMed Central

    Angiari, Stefano; Donnarumma, Tiziano; Rossi, Barbara; Dusi, Silvia; Pietronigro, Enrica; Zenaro, Elena; Della Bianca, Vittorina; Toffali, Lara; Piacentino, Gennj; Budui, Simona; Rennert, Paul; Xiao, Sheng; Laudanna, Carlo; Casasnovas, Jose M.; Kuchroo, Vijay K.; Constantin, Gabriela

    2014-01-01

    SUMMARY Selectins play a central role in leukocyte trafficking by mediating tethering and rolling on vascular surfaces. Here we have reported that T cell immunoglobulin and mucin domain 1 (TIM-1) is a P-selectin ligand. We have shown that human and murine TIM-1 binds to P-selectin, and that TIM-1 mediates tethering and rolling of T helper-1 (Th1) and Th17, but not Th2 and regulatory T cells on P-selectin. Th1 and Th17 cells lacking the TIM-1 mucin domain showed reduced rolling in thrombin-activated mesenteric venules and inflamed brain microcirculation. Inhibition of TIM-1 had no effect on naive T cell homing, but reduced T cell recruitment in a skin hypersensitivity model and blocked experimental autoimmune encephalomyelitis. Uniquely, the TIM-1 IgV domain was also required for P-selectin binding. Our data demonstrate that TIM-1 is a major P-selectin ligand with a specialized role in T cell trafficking during inflammatory responses and the induction of autoimmune disease. PMID:24703780

  4. Systemic administration of human adipose-derived stem cells reverts nociceptive hypersensitivity in an experimental model of neuropathy.

    PubMed

    Sacerdote, Paola; Niada, Stefania; Franchi, Silvia; Arrigoni, Elena; Rossi, Alice; Yenagi, Vijay; de Girolamo, Laura; Panerai, Alberto Emilio; Brini, Anna Teresa

    2013-04-15

    Over the last decade, it has been proved that mesenchymal stem cells (MSCs) elicit anti-inflammatory effects. MSCs from adipose tissue (hASCs) differentiate into cells of the mesodermal lineage and transdifferentiate into ectodermal-origin cells. Although there are various etiologies to chronic pain, one common feature is that painful states are associated with increased inflammation. We believe in hASCs as a therapeutic tool also in pathologies involving neuroinflammation and neuronal tissue damage. We have investigated the effect of hASCs injected in a model of neuropathic pain [(mouse sciatic nerve chronic constriction injury (CCI)]. hASCs from 5 donors were characterized, and no major differences were depicted. hASCs were cryopreserved and grown on demand. About 1×10(6), 3×10(6), and 6×10(6) hASCs were intravenously injected into normal immunocompetent mice. No mouse died, and no macroscopic toxicity or behavioral changes were observed, confirming the safety of hASCs. hASCs, intravenously (i.v.) injected into C57BL/6 mice when the neuropathic pain was already established, induced a significant reduction in mechanical allodynia and a complete reversion of thermal hyperalgesia in a dose-response fashion, already 1 day after administration. Moreover, the hASCs effect can be boosted by repeated administrations, allowing a prolonged therapeutic effect. Treatment decreased the level of the CCI-induced proinflammatory cytokine interleukin (IL)-1β and activated the anti-inflammatory cytokine IL-10 in the lesioned nerve. hASCs treatment also restored normal inducible nitric oxide synthase expression in the spinal cord of CCI animals. Our data suggest that hASCs are worthy of further studies as an anti-inflammatory therapy in the treatment of neuropathic pain or chronic inflammatory diseases.

  5. Cell-autonomous iodothyronine deiodinase expression mediates seasonal plasticity in immune function.

    PubMed

    Stevenson, Tyler J; Onishi, Kenneth G; Bradley, Sean P; Prendergast, Brian J

    2014-02-01

    Annual rhythms in morbidity and mortality are well-documented, and host defense mechanisms undergo marked seasonal phenotypic change. Siberian hamsters (Phodopus sungorus) exhibit striking immunological plasticity following adaptation to short winter day lengths (SD), including increases in blood leukocytes and in the magnitude of T cell-mediated immune responses. Thyroid hormone (TH) signaling is rate-limited by tissue-level expression of iodothyronine deiodinase types II and III (dio2, dio3), and dio2/dio3 expression in the central nervous system gate TH-dependent transduction of photoperiod information into the neuroendocrine system. THs are also potent immunomodulators, but their role in seasonal immunobiology remains unexamined. Here we report that photoperiod-driven changes in triiodothyronine (T3) signaling mediate seasonal changes in multiple aspects of immune function. Transfer from long days (LD) to SD inhibited leukocyte dio3 expression, which increased cellular T4→T3 catabolism. T3 was preferentially localized in the lymphocyte cytoplasm, consistent with a non-nuclear role of T3 in lymphoid cell differentiation and maturation. Exposure to SD upregulated leukocyte DNA methyltransferase expression and markedly increased DNA methylation in the dio3 proximal promoter region. Lastly, to bypass low endogenous T3 biosynthesis in LD lymphocytes, LD hamsters were treated with T3, which enhanced T cell-dependent delayed-type hypersensitivity inflammatory responses and blood leukocyte concentrations in a dose-dependent manner, mimicking effects of SD on these immunophenotypes. T3 signaling represents a novel mechanism by which environmental day length cues impact the immune system: changes in day length alter lymphoid cell T3-signaling via epigenetic transcriptional control of dio3 expression.

  6. Cell-autonomous iodothyronine deiodinase expression mediates seasonal plasticity in immune function

    PubMed Central

    Stevenson, Tyler J; Onishi, Kenneth G; Bradley, Sean P; Prendergast, Brian J

    2013-01-01

    Annual rhythms in morbidity and mortality are well-documented, and host defense mechanisms undergo marked seasonal phenotypic change. Siberian hamsters (Phodopus sungorus) exhibit striking immunological plasticity following adaptation to short winter day lengths (SD), including increases in blood leukocytes and in the magnitude of T cell-mediated immune responses. Thyroid hormone (TH) signaling is rate-limited by tissue-level expression of iodothyronine deiodinase types II and III (dio2, dio3), and dio2/dio3 expression in the central nervous system gate TH-dependent transduction of photoperiod information into the neuroendocrine system. THs are also potent immunomodulators, but their role in seasonal immunobiology remains unexamined. Here we report that photoperiod-driven changes in triiodothyronine (T3) signaling mediate seasonal changes in multiple aspects of immune function. Transfer from long days (LD) to SD inhibited leukocyte dio3 expression, which increased cellular T4→T3 catabolism. T3 was preferentially localized in the lymphocyte cytoplasm, consistent with a non-nuclear role of T3 in lymphoid cell differentiation and maturation. Exposure to SD upregulated leukocyte DNA methyltransferase expression and markedly increased DNA methylation in the dio3 proximal promoter region. Lastly, to bypass low endogenous T3 biosynthesis in LD lymphocytes, LD hamsters were treated with T3, which enhanced T cell-dependent delayed-type hypersensitivity inflammatory responses and blood leukocyte concentrations in a dose-dependent manner, mimicking effects of SD on these immunophenotypes. T3 signaling represents a novel mechanism by which environmental day length cues impact the immune system: changes in day length alter lymphoid cell T3-signaling via epigenetic transcriptional control of dio3 expression. PMID:24145050

  7. Immune responses to ectoparasites of horses, with a focus on insect bite hypersensitivity.

    PubMed

    Wilson, A D

    2014-11-01

    Horses are affected by a wide variety of arthropod ectoparasites, ranging from lice which spend their entire life on the host, through ticks which feed over a period of days, to numerous biting insects that only transiently visit the host to feed. The presence of ectoparasites elicits a number of host responses including innate inflammatory responses, adaptive immune reactions and altered behaviour; all of which can reduce the severity of the parasite burden. All of these different responses are linked through immune mechanisms mediated by mast cells and IgE antibodies which have an important role in host resistance to ectoparasites, yet immune responses also cause severe pathological reactions. One of the best described examples of such pathological sequelae is insect bite hypersensitivity (IBH) of horses; an IgE-mediated type 1 hypersensitivity to the salivary proteins of Culicoides spp. associated with T-helper-2 production of IL4 and IL13. Importantly, all horses exposed to Culicoides have an expanded population of Culicoides antigen-specific T cells with this pattern of cytokine production, but in those which remain healthy, the inflammatory reaction is tempered by the presence of FoxP3+ CD4+ regulatory T cells that express IL10 and TGF-beta, which suppresses the IL4 production by Culicoides antigen-activated T cells.

  8. Nanomedicine-mediated cancer stem cell therapy.

    PubMed

    Shen, Song; Xia, Jin-Xing; Wang, Jun

    2016-01-01

    Circumstantial evidence suggests that most tumours are heterogeneous and contain a small population of cancer stem cells (CSCs) that exhibit distinctive self-renewal, proliferation and differentiation capabilities, which are believed to play a crucial role in tumour progression, drug resistance, recurrence and metastasis in multiple malignancies. Given that the existence of CSCs is a primary obstacle to cancer therapy, a tremendous amount of effort has been put into the development of anti-CSC strategies, and several potential approaches to kill therapeutically-resistant CSCs have been explored, including inhibiting ATP-binding cassette transporters, blocking essential signalling pathways involved in self-renewal and survival of CSCs, targeting CSCs surface markers and destroying the tumour microenvironment. Meanwhile, an increasing number of therapeutic agents (e.g. small molecule drugs, nucleic acids and antibodies) to selectively target CSCs have been screened or proposed in recent years. Drug delivery technology-based approaches hold great potential for tackling the limitations impeding clinical applications of CSC-specific agents, such as poor water solubility, short circulation time and inconsistent stability. Properly designed nanocarrier-based therapeutic agents (or nanomedicines) offer new possibilities of penetrating CSC niches and significantly increasing therapeutic drug accumulation in CSCs, which are difficult for free drug counterparts. In addition, intelligent nanomedicine holds great promise to overcome pump-mediated multidrug resistance which is driven by ATP and to decrease detrimental effects on normal somatic stem cells. In this review, we summarise the distinctive biological processes related to CSCs to highlight strategies against inherently drug-resistant CSCs. We then focus on some representative examples that give a glimpse into state-of-the-art nanomedicine approaches developed for CSCs elimination. A perspective on innovative therapeutic

  9. Detection of cell mediated immune response to avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In birds, lymphomyeloid tissues develop from epithelial (Bursa of Fabricus or thymus) or mesenchymal tissue which are populated by heamatopoietic stem cells. These stem cells develop directly into immunologically competent B (bursa) and T (thymus) cells. Cell-mediated immunity (CMI) is a part of the...

  10. Cell-mediated immune responses to chlamydial antigens in guinea pigs injected with inactivated chlamydiae.

    PubMed

    Senyk, G; Sharp, M; Stites, D P; Hanna, L; Keshishyan, H; Jawetz, E

    1980-01-01

    Cell-mediated immunity (CMI) to chlamydial antigens was readily induced in guinea pigs by a single injection of Betaprone-inactivated chlamydiae in complete Freund adjuvant. The CMI was measured in vivo by delayed hypersensitivity skin tests, and in vitro by inhibition of migration of peritoneal exudate cells and by proliferation of lymph node lymphocytes. There was an overall correlation between in vivo and in vitro responses. Of the in vitro assays, migration inhibition reflected the state of sensitization, as judged by skin tests, more uniformly than lymphocyte stimulation. Extensive inter- and intra-species cross-reactivity was noted between LB-1, a strain of C. trachomatis, and three strains of C. psittaci, 6BC, GPIC, and 562F. Cross-reactivity between LB-1 and 6BC was one-way only, by all three parameters: LB-1 elicited strong cross-reactions in 6BC-immunized animals but not vice versa. Antichlamydial antibodies could not be demonstrated in any of the animals by microimmunofluorescence.

  11. Histamine suppresses regulatory T cells mediated by TGF-β in murine chronic allergic contact dermatitis.

    PubMed

    Tamaka, Kyoko; Seike, Masahiro; Hagiwara, Tamio; Sato, Atsushi; Ohtsu, Hiroshi

    2015-04-01

    Regulatory T cells (Tregs) suppress effector T cells and ameliorate contact hypersensitivity (CH); however, the role of Tregs in chronic allergic contact dermatitis (CACD) has not been assessed. Repeated elicitation of CH has been used to produce CACD models in mice. We previously showed that the presence of histamine facilitates the creation of eczematous lesions in this model using histidine decarboxylase (HDC) (-/-) mice. Therefore, the effects of histamine on Tregs in the CACD model were investigated in this study. CACD was developed by repeated epicutaneous application of 2, 4, 6-trinitro-1-chlorobenzene (TNCB) on HDC (+/+) and HDC (-/-) murine skin to assess the effects of histamine in CACD. Histamine aggravated CACD in the murine model and suppressed the number of Tregs in the skin. Histamine also suppressed the level of TGF-β1 in this model. Recombinant TGF-β1 or anti-TGF-β1 antibody was injected into the dorsal dermis of HDC (+/+) mice daily just before TNCB challenge to determine the effects of histamine-regulated TGF-β on the Treg population in CACD. Recombinant TGF-β1 injection promoted the infiltration of Tregs in the skin and the production of IL-10; however, anti-TGF-β1 antibody injection suppressed the number of Tregs in the skin and the production of IL-10. Histamine suppresses the number of Tregs in CACD, and this effect is mediated by TGF-β.

  12. Distinct histopathology of acute onset or abrupt exacerbation of hypersensitivity pneumonitis.

    PubMed

    Hariri, Lida P; Mino-Kenudson, Mari; Shea, Barry; Digumarthy, Subba; Onozato, Maristela; Yagi, Yukako; Fraire, Armando E; Matsubara, Osamu; Mark, Eugene J

    2012-05-01

    Hypersensitivity pneumonitis is an inflammatory lung disease that develops in response to exposure to antigen. Cases can be stratified by the duration of exposure and speed of symptom progression into acute, subacute, and chronic hypersensitivity pneumonitis. Although the pathologic features of subacute hypersensitivity pneumonitis are well established and those of chronic hypersensitivity pneumonitis have been reported, little is known about the histopathology of acute hypersensitivity pneumonitis. We evaluated the pathologic features of 5 patients with clinically confirmed hypersensitivity pneumonitis and rapid onset of symptoms and 3 patients with subacute or chronic hypersensitivity pneumonitis with symptom exacerbation. Histopathologic features assessed in each case included those characteristic of subacute hypersensitivity pneumonitis (bronchiolocentric chronic inflammation, histiocytic aggregates, and bronchiolitis obliterans), those associated with acute inflammation (fibrin deposition and neutrophilic infiltrate), and fibrosis. The classic features of hypersensitivity pneumonitis were identified in all 8 cases, with 1 also exhibiting fixed fibrosis confirming underlying chronic hypersensitivity pneumonitis. Fibrin deposition was present in 8 (100%) of 8 cases, and its extent was significant (28% surface area fibrin deposition/total disease area on average). Two had intra-alveolar fibrin so marked that it resembled acute fibrinous and organizing pneumonia. In addition, prominent interstitial neutrophilic infiltrate (≥5 cells/high-power field) was seen in all cases. These features have not been reported as characteristics of subacute or chronic hypersensitivity pneumonitis. Increased fibrin deposition and neutrophilic infiltrate may characterize acute hypersensitivity pneumonitis or abrupt exacerbation of hypersensitivity pneumonitis, and these along with characteristic features of subacute hypersensitivity pneumonitis (granulomatous inflammation and

  13. In vivo testing confirms a blunting of the human cell-mediated immune mechanism during space flight

    NASA Technical Reports Server (NTRS)

    Taylor, G. R.; Janney, R. P.

    1992-01-01

    The cell-mediated immune (CMI) mechanism was evaluated in 10 space shuttle astronauts by measuring their delayed-type hypersensitivity response to seven common recall antigens. The Multitest CMI test system was used to administer antigens of tetanus, diphtheria, Streptococcus, Proteus, old tuberculin, Candida, and Trichophyton to the forearm 46 h before nominal mission termination; readings were conducted 2 h after landing. The mean number of reactions was reduced from 4.5 preflight to 3.0 inflight, and the mean reaction score was reduced from 21.4 to 13.7 mm inflight. The data presented suggest that the CMI system is still being degraded by space flight conditions on day 4 and that between day 5 and day 10, the depression maximizes and the system begins to adjust to the new conditions. The relation of these in vivo findings to previously reported in vitro results is discussed.

  14. Depletion of regulatory T cells leads to an exacerbation of delayed-type hypersensitivity arthritis in C57BL/6 mice that can be counteracted by IL-17 blockade

    PubMed Central

    Atkinson, Sara Marie; Hoffmann, Ute; Hamann, Alf; Bach, Emil; Danneskiold-Samsøe, Niels Banhos; Kristiansen, Karsten; Serikawa, Kyle; Fox, Brian; Kruse, Kim; Haase, Claus; Skov, Søren; Nansen, Anneline

    2016-01-01

    ABSTRACT Rodent models of arthritis have been extensively used in the elucidation of rheumatoid arthritis (RA) pathogenesis and are instrumental in the development of therapeutic strategies. Here we utilise delayed-type hypersensitivity arthritis (DTHA), a model in C57BL/6 mice affecting one paw with synchronised onset, 100% penetrance and low variation. We investigate the role of regulatory T cells (Tregs) in DTHA through selective depletion of Tregs and the role of IL-17 in connection with Treg depletion. Given the relevance of Tregs in RA, and the possibility of developing Treg-directed therapies, this approach could be relevant for advancing the understanding of Tregs in inflammatory arthritis. Selective depletion of Tregs was achieved using a Foxp3-DTR-eGFP mouse, which expresses the diphtheria toxin receptor (DTR) and enhanced green fluorescent protein (eGFP) under control of the Foxp3 gene. Anti-IL-17 monoclonal antibody (mAb) was used for IL-17 blockade. Numbers and activation of Tregs increased in the paw and its draining lymph node in DTHA, and depletion of Tregs resulted in exacerbation of disease as shown by increased paw swelling, increased infiltration of inflammatory cells, increased bone remodelling and increased production of inflammatory mediators, as well as increased production of anti-citrullinated protein antibodies. Anti-IL-17 mAb treatment demonstrated that IL-17 is important for disease severity in both the presence and absence of Tregs, and that IL-17 blockade is able to rescue mice from the exacerbated disease caused by Treg depletion and caused a reduction in RANKL, IL-6 and the number of neutrophils. We show that Tregs are important for the containment of inflammation and bone remodelling in DTHA. To our knowledge, this is the first study using the Foxp3-DTR-eGFP mouse on a C57BL/6 background for Treg depletion in an arthritis model, and we here demonstrate the usefulness of the approach to study the role of Tregs and IL-17 in arthritis

  15. Sulfite hypersensitivity. A critical review

    SciTech Connect

    Gunnison, A.F.; Jacobsen, D.W.

    1987-01-01

    Sulfiting agents (sulfur dioxide and the sodium and potassium salts of bisulfite, sulfite, and metabisulfite) are widely used as preservatives in foods, beverages, and pharmaceuticals. Within the past 5 years, there have been numerous reports of adverse reactions to sulfiting agents. This review presents a comprehensive compilation and discussion of reports describing reactions to ingested, inhaled, and parenterally administered sulfite. Sulfite hypersensitivity is usually, but not exclusively, found within the chronic asthmatic population. Although there is some disagreement on its prevalence, a number of studies have indicated that 5 to 10% of all chronic asthmatics are sulfite hypersensitive. This review also describes respiratory sulfur dioxide sensitivity which essentially all asthmatics experience. Possible mechanisms of sulfite hypersensitivity and sulfur dioxide sensitivity are discussed in detail. Sulfite metabolism and the role of sulfite oxidase in the detoxification of exogenous sulfite are reviewed in relationship to the etiology of sulfite hypersensitivity. 147 references.

  16. Comparative immunotoxicity of 2,2`-dichlorodiethyl sulfide and cyclophosphamide: Evaluation of L1210 tumor cell resistance, cell-mediated immunity, and humoral immunity. (Reannouncement with new availability information)

    SciTech Connect

    Blank, J.A.; Joiner, R.L.; Houchens, D.P.; Dill, G.S.; Hobson, D.W.

    1991-12-31

    The immunotoxicity of 2,2`-dichlorodiethyl sulfide (sulfur mustard, SM),on humoral and cell-mediated immunity was compared with that of the nitrogen mustard 2-(bis(2-chloroethyl) amino)tetrahydro- 2H-1,3,2-oxazophosphorine 2-oxide (cyclophosphamide, CP). SM and CP had similar effects on thymic and splenic weights, spleen cell number, and the formation of antibody producing cells to sheep red blood cells (sRBC) when examined 5 days after exposure, but differed in their effects on body weights. Although there were no differences in the delayed hypersensitivity response to keyhole limpet hemocyanin, CP and SM had different effects in the L1210 tumor cell allograft rejection assay. CP, but not SM, decreased the 28 day survival rate of allogeneic mice exposed to a sublethal L1210 tumor challenge. The differing effects on survival to the L1210 tumor challenge could not be attributed to a direct cytotoxic effect of SM on the L1210 tumor cells as SM did not increase the survival rate or mediansurvival time of syngeneic mice exposed to a lethal L1210 tumor cell challenge. In summary, SM and CP had immunosuppressive effects in the humoral immune assay. Although neither compound suppressed the delayed hypersensitivity response, CP was found to suppress host resistance to L1210 tumor cells.

  17. Effect of chronic microwave radiation on T cell-mediated immunity in the rabbit

    NASA Astrophysics Data System (ADS)

    Nageswari, K. Sri; Sarma, K. R.; Rajvanshi, V. S.; Sharan, R.; Sharma, Manju; Barathwal, Vinita; Singh, Vinod

    1991-06-01

    Experiments were conducted to elucidate the effects of chronic low power-level microwave radiation on the immunological systems of rabbits. Fourteen male Belgian white rabbits were exposed to microwave radiation at 5 mW/cm2, 2.1 GHz, 3 h daily, 6 days/week for 3 months in two batches of 7 each in specially designed miniature anechoicchambers. Seven rabbits were subjected to sham exposure for identical duration. The microwave energy was provided through S band standard gain horns connected to a 4K3SJ2 Klystron power amplifier. The first batch of animals were assessed for T lymphocyte-mediated cellular immune response mechanisms and the second batch of animals for B lymphocyte-mediated humoral immune response mechanisms. The peripheral blood samples collected monthly during microwave/sham exposure and during follow-up (5/14 days after termination of exposures, in the second batch animals only) were analysed for T lymphocyte numbers and their mitogen responsiveness to ConA and PHA. Significant suppression of T lymphocyte numbers was noted in the microwave group at 2 months ( P<0.01, Δ% 21.5%) and during follow-up ( P<0.01, Δ% 30.2%). The first batch animals were initially sensitised with BCG and challenged with tuberculin (0.03 ml) at the termination of microwave irradiation/sham exposure and the increase in foot pad thickness (Δ mm), which is a measure of T cell-mediated immunity (delayed type hypersensitivity response, DTH) was noted in both the groups. The microwave group revealed a better response than the control group (Δ%+12.4 vs.+7.54). The animals were sacrified and the tissue T lymphocyte counts (spleen and lymph node) were analysed. No significant variation was observed in the tissue T lymphocyte counts of microwave-irradiated rabbits. From these results it is speculated that the T lymphocytes are sequestered to various lymphoid organs under the influence of microwaves. A sub-population of T cells known as T helper cells (mediating DTH response) are

  18. Lung Transplantation for Hypersensitivity Pneumonitis

    PubMed Central

    Singer, Jonathan P.; Koth, Laura; Mooney, Joshua; Golden, Jeff; Hays, Steven; Greenland, John; Wolters, Paul; Ghio, Emily; Jones, Kirk D.; Leard, Lorriana; Kukreja, Jasleen; Blanc, Paul D.

    2015-01-01

    BACKGROUND: Hypersensitivity pneumonitis (HP) is an inhaled antigen-mediated interstitial lung disease (ILD). Advanced disease may necessitate the need for lung transplantation. There are no published studies addressing lung transplant outcomes in HP. We characterized HP outcomes compared with referents undergoing lung transplantation for idiopathic pulmonary fibrosis (IPF). METHODS: To identify HP cases, we reviewed records for all ILD lung transplantation cases at our institution from 2000 to 2013. We compared clinical characteristics, survival, and acute and chronic rejection for lung transplant recipients with HP to referents with IPF. We also reviewed diagnoses of HP discovered only by explant pathology and looked for evidence of recurrent HP after transplant. Survival was compared using Kaplan-Meier methods and Cox proportional hazard modeling. RESULTS: We analyzed 31 subjects with HP and 91 with IPF among 183 cases undergoing lung transplantation for ILD. Survival at 1, 3, and 5 years after lung transplant in HP compared with IPF was 96%, 89%, and 89% vs 86%, 67%, and 49%, respectively. Subjects with HP manifested a reduced adjusted risk for death compared with subjects with IPF (hazard ratio, 0.25; 95% CI, 0.08-0.74; P = .013). Of the 31 cases, the diagnosis of HP was unexpectedly made at explant in five (16%). Two subjects developed recurrent HP in their allografts. CONCLUSIONS: Overall, subjects with HP have excellent medium-term survival after lung transplantation and, relative to IPF, a reduced risk for death. HP may be initially discovered only by review of the explant pathology. Notably, HP may recur in the allograft. PMID:25412059

  19. T-cell-mediated ganglionitis associated with acute sensory neuronopathy.

    PubMed

    Hainfellner, J A; Kristoferitsch, W; Lassmann, H; Bernheimer, H; Neisser, A; Drlicek, M; Beer, F; Budka, H

    1996-04-01

    A 67-year-old man presented with acute painful sensory loss, areflexia, ataxia, urinary retention, and severe constipation and became unable to walk within 2 weeks. He died suddenly 5 weeks after the onset of symptoms. Autopsy revealed widespread inflammation of sensory and autonomic ganglia with immunocytochemical evidence of a CD8+ T cell-mediated cytotoxic attack against ganglion neurons. This observation suggests a novel pathogenetic mechanism of immune-mediated human ganglion cell damage comparable to mechanisms operating in polymyositis.

  20. Epstein-Barr Virus Reactivation Associated with Diminished Cell-Mediated Immunity in Antarctic Expeditioners

    NASA Technical Reports Server (NTRS)

    Pierson, Duane L.; Mehta, Satish K.; Cooley, Helen; Dubow, Robin; Lugg, Desmond

    1999-01-01

    Reactivation of Epstein-Barr virus (EBV) and cell-mediated immune (CMI) responses were followed in 16 Antarctic expeditioners during winter-over isolation at two Australian National Antarctic Research Expedition stations. Delayed-type hypersensitivity skin testing was used as an indicator of the CMI response, which was evaluated two times before winter isolation and three times during isolation. At all five evaluation times, 8 or more of the 16 subjects had a diminished. CMI response. Diminished CMI was observed on every test occasion in 4/16 subjects; only 2/16 subjects exhibited normal CMI responses for all five tests. A polymerase chain reaction (PCR) assay was used to detect EBV DNA in saliva specimens collected before, after, and during the winter isolation. EBV DNA was present in 17% (111/642) of the saliva specimens; all 16 subjects shed EBV in their saliva on at least one occasion. The probability of EBV shedding increased (p=0.013) from 6% before or after winter isolation to 13% during the winter period. EBV appeared in saliva during the winter isolation more frequently (p<0.0005) when CMI responsiveness was diminished than when CMI status was normal. The findings indicate that the psychosocial, physical, and other stresses associated with working and living in physical isolation during the Antarctic winter results in diminished CMI and an accompanying increased reactivation and shedding of latent viruses.

  1. Melatonin treatment prevents modulation of cell-mediated immune response induced by propoxur in rats.

    PubMed

    Suke, Sanvidhan G; Pathak, Rahul; Ahmed, Rafat S; Tripathi, A K; Banerjee, B D

    2008-08-01

    The effect of melatonin, a major secretory product of the pineal gland, in attenuation of propoxur (2-isopropoxy phenyl N-methyl carbamate)-induced modulation of cell-mediated immune (CMI) response was studied in rats. Male Wistar albino rats were exposed to propoxur (a widely used pesticide) orally (10 mg/kg) and/or melatonin (10 mg/kg) orally for 4 weeks. CMI was measured by delayed-type hypersensitivity (DTH), leucocyte and macrophage migration inhibition (LMI and MMI) responses and estimation of cytokines TNF-alpha and IFN-gamma levels. Rats exposed to propoxur for 4 weeks showed significant decrease in DTH, LMI and MMI responses. Propoxur also suppressed TNF-alpha and IFN-gamma production significantly. Administration of melatonin alone caused a significant increase in DTH response. Although there were no changes in the LMI and MMI response, the cytokine levels were significantly increased, as compared to control. Co-administration of melatonin along with propoxur significantly nullified the effect of the pesticide on the CMI response, except DTH and reversed levels of cytokines to near control/normal values. Thus, melatonin treatment considerably attenuated immunomodulation caused by sub-chronic treatment of propoxur in experimental animals.

  2. Epstein-Barr virus reactivation associated with diminished cell-mediated immunity in antarctic expeditioners

    NASA Technical Reports Server (NTRS)

    Mehta, S. K.; Pierson, D. L.; Cooley, H.; Dubow, R.; Lugg, D.

    2000-01-01

    Epstein-Barr virus (EBV) reactivation and cell-mediated immune (CMI) responses were followed in 16 Antarctic expeditioners during winter-over isolation at 2 Australian National Antarctic Research Expedition stations. Delayed-type hypersensitivity (DTH) skin testing was used as an indicator of the CMI response, that was evaluated 2 times before winter isolation and 3 times during isolation. At all 5 evaluation times, 8 or more of the 16 subjects had a diminished CMI response. Diminished DTH was observed on every test occasion in 4/16 subjects; only 2/16 subjects exhibited normal DTH responses for all 5 tests. A polymerase chain reaction (PCR) assay was used to detect EBV DNA in saliva specimens collected before, during, and after the winter isolation. EBV DNA was present in 17% (111/642) of the saliva specimens; all 16 subjects shed EBV in their saliva on at least 1 occasion. The probability of EBV shedding increased (P = 0.013) from 6% before or after winter isolation to 13% during the winter period. EBV appeared in saliva during the winter isolation more frequently (P < 0.0005) when DTH response was diminished than when DTH was normal. The findings indicate that the psychosocial, physical, and other stresses associated with working and living in physical isolation during the Antarctic winter result in diminished CMI and an accompanying increased reactivation and shedding of latent viruses.

  3. Senescence and programmed cell death in plants: polyamine action mediated by transglutaminase

    PubMed Central

    Del Duca, Stefano; Serafini-Fracassini, Donatella; Cai, Giampiero

    2014-01-01

    Research on polyamines (PAs) in plants laps a long way of about 50 years and many roles have been discovered for these aliphatic cations. PAs regulate cell division, differentiation, organogenesis, reproduction, dormancy-break and senescence, homeostatic adjustments in response to external stimuli and stresses. Nevertheless, the molecular mechanisms of their multiple activities are still matter of research. PAs are present in free and bound forms and interact with several important cell molecules; some of these interactions may occur by covalent linkages catalyzed by transglutaminase (TGase), giving rise to “cationization” or cross-links among specific proteins. Senescence and programmed cell death (PCD) can be delayed by PAs; in order to re-interpret some of these effects and to obtain new insights into their molecular mechanisms, their conjugation has been revised here. The TGase-mediated interactions between proteins and PAs are the main target of this review. After an introduction on the characteristics of this enzyme, on its catalysis and role in PCD in animals, the plant senescence and PCD models in which TGase has been studied, are presented: the corolla of naturally senescing or excised flowers, the leaves senescing, either excised or not, the pollen during self-incompatible pollination, the hypersensitive response and the tuber storage parenchyma during dormancy release. In all the models examined, TGase appears to be involved by a similar molecular mechanism as described during apoptosis in animal cells, even though several substrates are different. Its effect is probably related to the type of PCD, but mostly to the substrate to be modified in order to achieve the specific PCD program. As a cross-linker of PAs and proteins, TGase is an important factor involved in multiple, sometimes controversial, roles of PAs during senescence and PCD. PMID:24778637

  4. Lymphocyte transformation studies in drug hypersensitivity

    PubMed Central

    Warrington, R.J.; Tse, K.S.

    1979-01-01

    In a group of patients with clinically diagnosed drug hypersensitivity the in vitro lymphocyte response to the suspected drug was assessed by the lymphocyte transformation test. The test gave positive results in all 15 patients with penicillin-induced immediate or accelerated allergic reactions and positive immediate skin-test reactivity to the major or the minor antigenic determinant of penicillin, or both, but in only 3 of the 12 patients with delayed-onset maculopapular rashes induced by penicillin, despite positive immediate reactivity to the skin-test reagents. Lymphocyte stimulation greater than five times the control level was demonstrated for five patients with penicillin-induced erythroderma, Stevens-Johnson syndrome or a serum-sickness-like illness, or with methicillin-induced interstitial nephritis, all of whom had negative reactions to the appropriate skin-test reagents. A low level of stimulation was seen in eight other skin-test-negative patients with possible allergic reactions induced by penicillins. However, in all subjects tested the stimulation was significantly greater than the mean for control subjects. For 9 of 11 patients with isoniazid-induced hepatitis or maculopapular rashes, but for only 8 of 31 patients with eruptions induced by a variety of drugs other than penicillins and isoniazid, significant stimulation occurred in the lymphocyte transformation test. It is concluded that the lymphocyte transformation test is useful in the detection of hypersensitivity to the penicillins (although in IgE-mediated reactions skin testing is clearly preferable) and isoniazid but is of limited value in the demonstration of hypersensitivity to other drugs. PMID:445303

  5. Equine insect bite hypersensitivity: what do we know?

    PubMed

    Schaffartzik, A; Hamza, E; Janda, J; Crameri, R; Marti, E; Rhyner, C

    2012-06-30

    Insect bite hypersensitivity (IBH) is an allergic dermatitis of the horse caused by bites of insects of the genus Culicoides and is currently the best characterized allergic disease of horses. This article reviews knowledge of the immunopathogenesis of IBH, with a particular focus on the causative allergens. Whereas so far hardly any research has been done on the role of antigen presenting cells in the pathogenesis of IBH, recent studies suggest that IBH is characterized by an imbalance between a T helper 2 (Th2) and regulatory T cell (T(reg)) immune response, as shown both locally in the skin and with stimulated peripheral blood mononuclear cells. Various studies have shown IBH to be associated with IgE-mediated reactions against salivary antigens from Culicoides spp. However, until recently, the causative allergens had not been characterized at the molecular level. A major advance has now been made, as 11 Culicoides salivary gland proteins have been identified as relevant allergens for IBH. Currently, there is no satisfactory treatment of IBH. Characterization of the main allergens for IBH and understanding what mechanisms induce a healthy or allergic immune response towards these allergens may help to develop new treatment strategies, such as immunotherapy.

  6. Immediate hypersensitivity reaction with mango.

    PubMed

    Shah, Ashok; Gera, Kamal

    2014-01-01

    Hypersensitivity to the fruit mango is extremely rare and can exhibit either as immediate or delayed reactions. Since 1939, only 22 patients (10 with immediate type I reactions and 12 with delayed) have been documented with allergy to mango. History of atopy and geographical region may influence the type of reaction. Immediate reactions occurred most often in patients with history of atopy, while delayed reactions developed in non-atopic individuals. Clustering of delayed hypersensitivity reports from Australia and immediate reactions from Europe has been documented. We report a 50-year-old man with immediate type I hypersensitivity to mango, who developed cough, wheezing dyspnoea, generalised itching and abdominal discomfort after ingestion of mango. Life threatening event can also happen making it imperative to diagnose on time, so as to prevent significant morbidity and potential mortality. PMID:25133813

  7. Dentin hypersensitivity and its management.

    PubMed

    Chu, C H; Lam, Anty; Lo, Edward C M

    2011-01-01

    Dentin hypersensitivity is a common patient complaint that is more prevalent than the profession realizes. It is important for dentists to diagnose dentin hypersensitivity by exclusion and provide appropriate treatment recommendations for patients. Various treatment methods have been proposed but no universally accepted desensitizing agent or treatment has been identified. When a patient has symptoms that can be attributed to dentin hypersensitivity, a thorough clinical examination should be carried out to rule out other likely causes prior to diagnosis and treatment. Depending on the identified cause, a combination of individualized instructions on proper oral health behaviors, use of at-home products, and professional treatment may be required to manage the problem. PMID:21903521

  8. The role for decorin in delayed-type hypersensitivity

    PubMed Central

    Seidler, Daniela G.; Mohamed, Negia A.; Bocian, Carla; Stadtmann, Anika; Hermann, Sven; Schäfers, Klaus; Schäfers, Michael; Iozzo, Renato V.; Zarbock, Alexander; Götte, Martin

    2016-01-01

    Decorin, a small leucine-rich proteoglycan, regulates extracellular matrix organization, growth factor-mediated signaling and cell growth. As decorin may directly modulate immune responses, we investigated its role in a mouse model of contact allergy (oxazolone-mediated delayed-type hypersensitivity, DTH) in decorin-deficient (Dcn−/−) and wild-type mice. Dcn−/− mice showed a reduced ear swelling 24 hours after oxazolone treatment with a concurrent attenuation of leukocyte infiltration. These findings were corroborated by reduced glucose metabolism as determined by 18FDG uptake in positron emission tomography scans. Unexpectedly, polymorphonuclear leukocyte numbers in Dcn−/− blood vessels were significantly increased, accompanied by large numbers of flattened leukocytes adherent to the endothelium. Intravital microscopy, flow chamber and static adhesion assays confirmed increased adhesion and reduced transmigration of Dcn−/− leukocytes. Circulating blood neutrophil numbers were significantly increased in Dcn−/− mice 24 hours after DTH elicitation, but only moderately increased in wild-type mice. Expression of the pro-inflammatory cytokine TNF-α was reduced, while syndecan-1 and ICAM-1 were overexpressed in inflamed ears of Dcn−/− mice, indicating that these adhesion molecules could be responsible for increased leukocyte adhesion. Decorin treatment of endothelial cells increased tyrosine phosphorylation and reduced syndecan-1 expression. Notably, absence of syndecan-1 in a genetic background lacking decorin rescued the attenuated DTH phenotype of Dcn−/− mice. Collectively, these results implicate a role for decorin in mediating DTH responses by influencing polymorphonuclear leukocyte attachment to the endothelium. This occurs via two non-mutually exclusive mechanisms that involve a direct anti-adhesive effect on polymorphonuclear leukocytes and a negative regulation of ICAM-1 and syndecan-1 expression. PMID:22043007

  9. Mammalian mediator 19 mediates H1299 lung adenocarcinoma cell clone conformation, growth, and metastasis.

    PubMed

    Xu, Lu-Lu; Guo, Shu-Liang; Ma, Su-Ren; Luo, Yong-Ai

    2012-01-01

    Mammalian mediator (MED) is a multi-protein coactivator that has been identified by several research groups. The involvement of the MED complex subunit 19 (MED 19) in the metastasis of lung adenocarcinoma cell line (H1299), which expresses the MED 19 subunit, was here investigated. When MED 19 expression was decreased by RNA interference H1299 cells demonstrated reduced clone formation, arrest in the S phase of the cell cycle, and lowered metastatic capacity. Thus, MED 19 appears to play important roles in the biological behavior of non-small cell lung carcinoma cells. These findings may be important for the development of novel lung carcinoma treatments.

  10. Immunization with extracellular proteins of Mycobacterium tuberculosis induces cell-mediated immune responses and substantial protective immunity in a guinea pig model of pulmonary tuberculosis.

    PubMed Central

    Pal, P G; Horwitz, M A

    1992-01-01

    We have studied the capacity of a selected fraction of Mycobacterium tuberculosis extracellular proteins (EP) released into broth culture by mid-logarithmic-growth-phase organisms to induce cell-mediated immune responses and protective immunity in a guinea pig model of pulmonary tuberculosis. Guinea pigs infected with M. tuberculosis by aerosol but not uninfected control guinea pigs exhibit strong cell-mediated immune responses to EP, manifest by dose-dependent cutaneous delayed-type hypersensitivity and splenic lymphocyte proliferation. Guinea pigs immunized subcutaneously with EP but not sham-immunized control guinea pigs also develop strong cell-mediated immune responses to EP, manifest by dose-dependent cutaneous delayed-type hypersensitivity and splenic lymphocyte proliferation. EP is nonlethal and nontoxic to guinea pigs upon subcutaneous immunization. Guinea pigs immunized with EP and then challenged with aerosolized M. tuberculosis exhibit protective immunity. In five independent experiments, EP-immunized guinea pigs were consistently protected against clinical illness, including weight loss. Compared with EP-immunized guinea pigs, sham-immunized control guinea pigs lost 12.9 +/- 2.0% (mean +/- SE) of their total weight. EP-immunized guinea pigs also had a 10-fold reduction in viable M. tuberculosis bacilli in their lungs and spleens (P = 0.004 and 0.001, respectively) compared with sham-immunized control animals. In the two experiments in which some guinea pigs died after aerosol challenge, EP-immunized animals were protected from death. Whereas all 12 (100%) EP-immunized guinea pigs survived challenge with aerosolized M. tuberculosis, only 6 of 12 (50%) sham-immunized control guinea pigs survived challenge (P = 0.007, Fisher exact test). This study demonstrates that actively growing M. tuberculosis cells release immunoprotective molecules extracellularly, that a subunit vaccine against tuberculosis is feasible, and that extracellular molecules of M

  11. CD13 mediates phagocytosis in human monocytic cells.

    PubMed

    Licona-Limón, Ileana; Garay-Canales, Claudia A; Muñoz-Paleta, Ofelia; Ortega, Enrique

    2015-07-01

    CD13 is a membrane-bound ectopeptidase, highly expressed on monocytes, macrophages, and dendritic cells. CD13 is involved in diverse functions, including degradation of peptide mediators, cellular adhesion, migration, viral endocytosis, signaling, and positive modulation of phagocytosis mediated by FcγRs and other phagocytic receptors. In this work, we explored whether besides acting as an accessory receptor, CD13 by itself is a primary phagocytic receptor. We found that hCD13 mediates efficient phagocytosis of large particles (erythrocytes) modified so as to interact with the cell only through CD13 in human macrophages and THP-1 monocytic cells. The extent of this phagocytosis is comparable with the phagocytosis mediated through the canonical phagocytic receptor FcγRI. Furthermore, we demonstrated that hCD13 expression in the nonphagocytic cell line HEK293 is sufficient to enable these cells to internalize particles bound through hCD13. CD13-mediated phagocytosis is independent of other phagocytic receptors, as it occurs in the absence of FcγRs, CR3, and most phagocytic receptors. Phagocytosis through CD13 is independent of its enzymatic activity but is dependent on actin rearrangement and activation of PI3K and is partially dependent on Syk activation. Moreover, the cross-linking of CD13 with antibodies rapidly induced pSyk in human macrophages. Finally, we observed that antibody-mediated cross-linking of hCD13, expressed in the murine macrophage-like J774 cell line, induces production of ROS. These results demonstrate that CD13 is a fully competent phagocytic receptor capable of mediating internalization of large particles.

  12. Studies on the mechanism of systemic suppression of contact hypersensitivity by UVB radiation. II. Differences in the suppression of delayed and contact hypersensitivity in mice.

    PubMed

    Kripke, M L; Morison, W L

    1986-05-01

    Exposing mice to UV radiation in the UVB range (280-320 nm) causes a selective immune suppression that contributes to the development of UVB-induced skin cancers. Among the immune responses suppressed by UVB irradiation are contact and delayed hypersensitivity reactions to haptens administered at unexposed sites. In these studies we provide evidence that delayed and contact hypersensitivity to the same hapten are not equivalent reactions and that they are suppressed in UVB-irradiated mice by 2 different mechanisms. This conclusion is based on the findings that: suppression of contact hypersensitivity could not be overcome by immunizing UVB-irradiated mice with hapten-coupled antigen-presenting cells derived from normal donors; and treatment of UVB-irradiated mice with methylprednisolone before immunization prevented the suppression of delayed hypersensitivity but had no effect on the suppression of contact hypersensitivity. The decreased ability to induce contact hypersensitivity in UVB-irradiated mice could be transferred to x-irradiated mice by reconstituting them with spleen cells from UVB-irradiated donors. The induction of hapten-specific suppressor cells, however, required both UVB irradiation and priming with hapten. Based on these results, we postulate that UVB irradiation induces a population of suppressor-inducer cells with specificity for a modified skin antigen and that this antigen serves as a carrier molecule for haptens that induce contact hypersensitivity and for tumor-specific transplantation antigens on UVB-induced tumors. PMID:3745963

  13. Dye-mediated photosensitization of murine neuroblastoma cells

    SciTech Connect

    Sieber, F.; Sieber-Blum, M.

    1986-04-01

    The purpose of this study was to determine if photosensitization mediated by the fluorescent dye, merocyanine 540, could be used to preferentially kill murine neuroblastoma cells in simulated autologous remission marrow grafts. Simultaneous exposure of Neuro 2a or NB41A3 neuroblastoma cells to merocyanine 540 and white light reduced the concentration of in vitro-clonogenic tumor cells 50,000-fold. By contrast, the same treatment had little effect on the graft's ability to rescue lethally irradiated syngeneic hosts. Lethally irradiated C57BL/6J X A/J F1 mice transplanted with photosensitized mixtures of neuroblastoma cells and normal marrow cells (1:100 or 1:10) survived without developing neuroblastomas. It is conceivable that merocyanine 540-mediated photosensitization will prove useful for the extracorporeal purging of residual neuroblastoma cells from human autologous remission marrow grafts.

  14. Delayed-type hypersensitivity responses in infected mice elicited by cytoplasmic fractions of Cryptococcus neoformans.

    PubMed Central

    Hay, R J; Reiss, E

    1978-01-01

    Four subcellular fractions of Cryptococcus neoformans prepared by differential centrifugation of disrupted whole yeast and a 3-day culture filtrate were examined for their ability to elicit delayed-type hypersensitivity in sensitized animals. The methods used to detect sensitization were (i) the footpad swelling test and inhibition of peritoneal macrophage migration in mice and (ii) skin testing in guinea pigs. Two entities, the post-mitochondrial supernatant and the culture filtrate, showed considerable activity in the footpad test, with 26- and 30-microliter 24-h swellings, respectively, at 6 weeks after infection. With the latter there was interference from a strong antibody-mediated 4-h skin reaction. The post-mitochondrial supernatant produced strong delayed-type hypersensitivity in guinea pigs at a dose of 69 microgram, and there was no demonstrable cross-reactivity in animals sensitized with heterologous fungi. The footpad swelling in mice correlated well with the macrophage migration inhibition test, with 71% inhibition in mice infected subcutaneously with C. neoformans at 6 weeks. However, mice infected intravenously developed poorer cell-mediated immunity than the subcutaneously infected mice. The post-mitochondrial supernatant was found to contain detectable amounts of cryptococcal capsular polysaccharide. Images PMID:365751

  15. Regulation of cell proliferation and apoptosis by bioactive lipid mediators.

    PubMed

    Clària, Joan

    2006-11-01

    Bioactive lipid mediators are increasingly being recognized as important endogenous regulators of cell activation, signaling, apoptosis and proliferation. Most of these lipid mediators are originated from cleavage of constituents of cellular membranes under the activity of phospholipases and sphingomyelinases. One of the major cascades of bioactive lipid mediator production involves the release of arachidonic acid from membrane phospholipids followed by the formation of eicosanoids (i.e. prostaglandins, leukotrienes and lipoxins). These biologically active metabolites of arachidonic acid are emerging as key regulators of cell proliferation and neo-angiogenesis and agents that specifically target these lipid mediators are being investigated as potential anticancer drugs. On the other hand, the lysophospholipid family, which includes members of the sphingomyelin-ceramide-sphingosine-1-phosphate and lysophosphatidic acid subfamilies, has evolved as an important group of lipid signaling molecules implicated in cellular differentiation, cell growth and apoptosis. This article reviews the most recent patents in this field of research, covering the following strategies based on the modulation of bioactive lipid mediators: (1) prostaglandin H synthase-2 inhibitors, (2) lipoxin analogs and aspirin-triggered lipid mediators, and (3) lysophosphatidic acid and other lysophospholipids. PMID:18221047

  16. Are Some Neurons Hypersensitive to Metallic Nanoparticles?

    PubMed Central

    Scott, Bobby R.

    2010-01-01

    Engineered metallic nanomaterial particles (MENAP) represent a significant breakthrough in developing new products for use by consumers and industry. Skin application (e.g., via creams and sprays containing nanoparticles) may provide a key route of potential intake of MENAP and can lead to retrograde transport from nerve endings in the skin to the somatosensory neurons in dorsal root ganglia (DRG). This paper uses a novel theoretical model (stochastic threshold microdose [STM] model) to characterize survival of DRG neurons exposed in cell culture replicates to copper nanoparticles, based on published data. Cell death via autophagy is assumed here to occur as a result of the uptake (called hits) of the nanoparticles by mitochondria. Theoretical results are presented for the existence of a hypersensitive fraction (about 20%) of neurons that are killed in significant numbers when on average > 1 hit to the at-risk mitochondria occurs. Further, most hypersensitive neurons appear to be killed by a cumulative exposure of about 2,000 micromolar-hours and the remaining resistant cells may have dysfunctional mitochondria. Based on these theoretical findings, it is predicted that repeated exposure (e.g., over years) of the skin of humans to MENAP could lead to significant nervous system damage and related morbidity. PMID:22423227

  17. Dendritic Cells: Cellular Mediators for Immunological Tolerance

    PubMed Central

    Chung, Chun Yuen J.; Ysebaert, Dirk; Berneman, Zwi N.

    2013-01-01

    In general, immunological tolerance is acquired upon treatment with non-specific immunosuppressive drugs. This indiscriminate immunosuppression of the patient often causes serious side-effects, such as opportunistic infectious diseases. Therefore, the need for antigen-specific modulation of pathogenic immune responses is of crucial importance in the treatment of inflammatory diseases. In this perspective, dendritic cells (DCs) can have an important immune-regulatory function, besides their notorious antigen-presenting capacity. DCs appear to be essential for both central and peripheral tolerance. In the thymus, DCs are involved in clonal deletion of autoreactive immature T cells by presenting self-antigens. Additionally, tolerance is achieved by their interactions with T cells in the periphery and subsequent induction of T cell anergy, T cell deletion, and induction of regulatory T cells (Treg). Various studies have described, modulation of DC characteristics with the purpose to induce antigen-specific tolerance in autoimmune diseases, graft-versus-host-disease (GVHD), and transplantations. Promising results in animal models have prompted researchers to initiate first-in-men clinical trials. The purpose of current review is to provide an overview of the role of DCs in the immunopathogenesis of autoimmunity, as well as recent concepts of dendritic cell-based therapeutic opportunities in autoimmune diseases. PMID:23762100

  18. Ion mediated targeting of cells with nanoparticles

    NASA Astrophysics Data System (ADS)

    Maheshwari, Vivek; Fu, Jinlong

    2010-03-01

    In eukaryotic cells, Ca^2+ ions are necessary for intracellular signaling, in activity of mitochondria and a variety of other cellular process that have been linked to cell apoptosis, proteins synthesis and cell-cycle regulation. Here we show that Ca^2+ ions, serving as the bio-compatible interface can be used to target Saccharomyces cerevisiae (SaC, baker's yeast), a model eukaryotic cell, with Au nanoparticles (10 nm). The Ca^2+ ions bind to the carboxylic acid groups in the citrate functionalized Au nanoparticles. This transforms the nanoparticles into micron long 1-D branched chain assemblies due to inter-particle dipole-dipole interaction and inter-particle bonding due to the divalent nature of the Ca^2+ ion. A similar transformation is observed with the use of divalent ions Mg^2+, Cd^2+ and Fe^2+. The 1-D assembly aids the interfacing of ion-nanoparticles on the cell by providing multiple contact points. Further monovalent ions such as Na^+ are also effective for the targeting of the cell with nanoparticles. However Na-Au nanoparticles are limited in their deposition as they exist in solution as single particles. The cells remain alive after the deposition process and their vitality is unaffected by the interfacing with ion-nanoparticles.

  19. Laser-mediated perforation of plant cells

    NASA Astrophysics Data System (ADS)

    Wehner, Martin; Jacobs, Philipp; Esser, Dominik; Schinkel, Helga; Schillberg, Stefan

    2007-07-01

    The functional analysis of plant cells at the cellular and subcellular levels requires novel technologies for the directed manipulation of individual cells. Lasers are increasingly exploited for the manipulation of plant cells, enabling the study of biological processes on a subcellular scale including transformation to generate genetically modified plants. In our setup either a picosecond laser operating at 1064 nm wavelength or a continuous wave laser diode emitting at 405 nm are coupled into an inverse microscope. The beams are focused to a spot size of about 1.5 μm and the tobacco cell protoplasts are irradiated. Optoporation is achieved when targeting the laser focal spot at the outermost edge of the plasma membrane. In case of the picosecond laser a single pulse with energy of about 0.4 μJ was sufficient to perforate the plasma membrane enabling the uptake of dye or DNA from the surrounding medium into the cytosol. When the ultraviolet laser diode at a power level of 17 mW is employed an irradiation time of 200 - 500 milliseconds is necessary to enable the uptake of macromolecules. In the presence of an EYFP encoding plasmid with a C-terminal peroxisomal signal sequence in the surrounding medium transient transformation of tobacco protoplasts could be achieved in up to 2% of the optoporated cells. Single cell perforation using this novel optoporation method shows that isolated plant cells can be permeabilized without direct manipulation. This is a valuable procedure for cell-specific applications, particularly where the import of specific molecules into plant cells is required for functional analysis.

  20. Evans blue dye adjuvant enhances delayed hypersensitivity while blocking immunity to Mycobacterium tuberculosis in mice.

    PubMed Central

    Anderson, D W; Crowle, A J

    1981-01-01

    Evans blue dye functions as an adjuvant with protein antigens in saline to induce cell-mediated immunological responses in mice. But when used to help induce cell-mediated tuberculoimmunity, it decreased mouse resistance to tuberculosis instead of helping induce immunity. This paradox was investigated. As could be expected from previous work with other antigens, the dye did promote induction of delayed hypersensitivity in mice to tuberculoprotein when injected in saline with killed tubercle bacilli. Peritoneal macrophages from mice injected with the dye responded normally to migration inhibition factor. Morphologically, these cells were moderately "activated" compared with similar cells taken from untreated mice. However, such cells incubated with tuberculosis growth inhibition lymphokine in an in vitro test for tuberculoimmunity did not express tuberculoimmunity, whereas macrophages from untreated mice did. Therefore, Evans blue dye did promote induction of cell-mediated immunological responses and tuberculoimmunity in lymphocytes, but under the conditions used in these experiments, it also blocked expression of tuberculoimmunity by macrophages. PMID:7012002

  1. Mast cells mediate malignant pleural effusion formation

    PubMed Central

    Giannou, Anastasios D.; Marazioti, Antonia; Spella, Magda; Kanellakis, Nikolaos I.; Apostolopoulou, Hara; Psallidas, Ioannis; Prijovich, Zeljko M.; Vreka, Malamati; Zazara, Dimitra E.; Lilis, Ioannis; Papaleonidopoulos, Vassilios; Kairi, Chrysoula A.; Patmanidi, Alexandra L.; Giopanou, Ioanna; Spiropoulou, Nikolitsa; Harokopos, Vaggelis; Aidinis, Vassilis; Spyratos, Dionisios; Teliousi, Stamatia; Papadaki, Helen; Taraviras, Stavros; Snyder, Linda A.; Eickelberg, Oliver; Kardamakis, Dimitrios; Iwakura, Yoichiro; Feyerabend, Thorsten B.; Rodewald, Hans-Reimer; Kalomenidis, Ioannis; Blackwell, Timothy S.; Agalioti, Theodora; Stathopoulos, Georgios T.

    2015-01-01

    Mast cells (MCs) have been identified in various tumors; however, the role of these cells in tumorigenesis remains controversial. Here, we quantified MCs in human and murine malignant pleural effusions (MPEs) and evaluated the fate and function of these cells in MPE development. Evaluation of murine MPE-competent lung and colon adenocarcinomas revealed that these tumors actively attract and subsequently degranulate MCs in the pleural space by elaborating CCL2 and osteopontin. MCs were required for effusion development, as MPEs did not form in mice lacking MCs, and pleural infusion of MCs with MPE-incompetent cells promoted MPE formation. Once homed to the pleural space, MCs released tryptase AB1 and IL-1β, which in turn induced pleural vasculature leakiness and triggered NF-κB activation in pleural tumor cells, thereby fostering pleural fluid accumulation and tumor growth. Evaluation of human effusions revealed that MCs are elevated in MPEs compared with benign effusions. Moreover, MC abundance correlated with MPE formation in a human cancer cell–induced effusion model. Treatment of mice with the c-KIT inhibitor imatinib mesylate limited effusion precipitation by mouse and human adenocarcinoma cells. Together, the results of this study indicate that MCs are required for MPE formation and suggest that MC-dependent effusion formation is therapeutically addressable. PMID:25915587

  2. Hypersensitivity pneumonitis in a high school teacher.

    PubMed

    Moniodis, A; Hamilton, T; Racila, E; Cockrill, B; McCunney, R

    2015-10-01

    Hypersensitivity pneumonitis (HP) is an inflammatory lung disease mediated by an immunological response to an inhaled antigen. Outbreaks of HP have been reported in industrial settings where manufacturing workers are exposed to water-based metalworking fluids (MWFs). Water-based MWFs promote growth of microorganisms and can be easily aerosolized and are thus potential aetiological agents of HP. We present a case of HP caused by exposure to water-based MWF in a vocational high school teacher. Culture of MWF used at his school grew Pseudomonas pseudoalcaligenes. This is the first known report of MWF-induced HP outside an industrial setting. The growth of Pseudomonas spp in this case recalls the earliest reports of the microbiology of MWF-induced HP and suggests that routine bacterial culture may be useful in the diagnosis of HP in workplaces without standard cleaning and biocide regulations. PMID:26136595

  3. SUMOylation-mediated regulation of cell cycle progression and cancer

    PubMed Central

    Eifler, Karolin; Vertegaal, Alfred C.O.

    2016-01-01

    SUMOylation plays critical roles during cell cycle progression. Many important cell cycle regulators, including many oncogenes and tumor suppressors, are functionally regulated via SUMOylation. The dynamic SUMOylation pattern observed throughout the cell cycle is ensured via distinct spatial and temporal regulation of the SUMO machinery. Additionally, SUMOylation cooperates with other post-translational modifications to mediate cell cycle progression. Deregulation of these SUMOylation and deSUMOylation enzymes causes severe defects in cell proliferation and genome stability. Different types of cancers were recently shown to be dependent on a functioning SUMOylation system, a finding that could potentially be exploited in anti-cancer therapies. PMID:26601932

  4. Environmental chemicals relevant for respiratory hypersensitivity: the indoor environment.

    PubMed

    Becher, R; Hongslo, J K; Jantunen, M J; Dybing, E

    1996-08-01

    The allergenic constituents of non-industrial indoor environments are predominantly found in the biologic fraction. Several reports have related biological particles such as mites and their excreta, dander from pets and other furred animals, fungi and bacteria to allergic manifestations including respiratory hypersensitivity among the occupants of buildings. Also, bacterial cell-wall components and the spores of toxin-producing moulds may contribute to the induction of hypersensitivity, but the relevance for human health is not yet determined. The knowledge regarding hypersensitivity and asthmatic reactions after exposure to chemical agents is primarily based on data from occupational settings with much higher exposure levels than usually found in non-industrial indoor environments. However, there is evidence that indoor exposure to tobacco smoke, some volatile organic compounds (VOC) and various combustion products (either by using unvented stoves or from outdoor sources) can be related to asthmatic symptoms. In some susceptible individuals, the development of respiratory hypersensitivity or elicitation of asthmatic symptoms may also be related to the indiscriminate use of different household products followed by exposure to compounds such as diisocyanates, organic acid anhydrides, formaldehyde, styrene and hydroquinone. At present, the contribution of the indoor environment both to the development of respiratory hypersensitivity and for triggering asthmatic symptoms is far from elucidated.

  5. Transcriptional regulator Id2 mediates CD8+ T cell immunity.

    PubMed

    Cannarile, Michael A; Lind, Nicholas A; Rivera, Richard; Sheridan, Alison D; Camfield, Kristin A; Wu, Bei Bei; Cheung, Kitty P; Ding, Zhaoqing; Goldrath, Ananda W

    2006-12-01

    Transcriptional programs that initiate and sustain the proliferation, differentiation and survival of CD8(+) T cells during immune responses are not completely understood. Here we show that inhibitor of DNA binding 2 (Id2), an antagonist of E protein transcription factors, was upregulated in CD8(+) T cells during infection and that expression of Id2 was maintained in memory CD8(+) T cells. Although Id2-deficient naive CD8(+) T cells recognized antigen and proliferated normally early after infection, effector CD8(+) T cells did not accumulate because the cells were highly susceptible to apoptosis. Id2-deficient CD8(+) T cells responding to infection had changes in the expression of genes that influence survival and had altered memory formation. Our data emphasize the importance of Id2 in regulating gene expression by CD8(+) T cells and the magnitude of effector responses, suggesting a mechanism involving Id protein- and E protein-mediated survival and differentiation of mature T cells.

  6. Cell-mediated immunity and lymphocyte populations in experimental Argentine hemorrhagic fever (Junín Virus).

    PubMed Central

    Carballal, G; Oubiña, J R; Rondinone, S N; Elsner, B; Frigerio, M J

    1981-01-01

    Guinea pigs infected with the XJ prototype strain of Junín virus reproduce the main features of Argentine hemorrhagic fever, showing hemorrhages, leukothrombocytopenia, and focal lymphoid tissue necrosis. Viral lymphotropism is shown by the presence of viral antigens, severe cytopathic effect, and high virus titers in lymphoid organs. A pronounced depression of humoral immune response to sheep erythrocytes as well as to the virus is described. This study was carried out to determine whether cellular immune response was also modified and which cell populations were affected. Delayed hypersensitivity skin reaction to purified protein derivative was found to be markedly depressed after infection. A noticeable decrease in both percentages and absolute T lymphocyte numbers, detected by E rosettes, in spleen and lymph nodes, together with a low absolute T cell number in peripheral blood, were observed. Total cell counts in spleen, lymph nodes, and peripheral blood were also reduced. On the contrary, no modification in percentages of B lymphocytes, as measured by EAC rosettes, was found. These results indicate that cell-mediated immunity is markedly impaired in guinea pigs infected with the XJ strain of Junín virus. Its relationship with the pathogenesis of the disease is discussed. PMID:6273314

  7. Hypersensitivity reactions to radiocontrast media: the role of complement activation.

    PubMed

    Szebeni, Janos

    2004-01-01

    Although intravenous use of radiocontrast media (RCM) for a variety of radiographic procedures is generally safe, clinically significant acute hypersensitivity reactions still occur in a significant percentage of patients. The mechanism of these anaphylactoid, or "pseudoallergic," reactions is complex, involving complement activation, direct degranulation of mast cells and basophils, and modulation of enzymes and proteolytic cascades in plasma. In this review, basic information on different RCMs and their reactogenicity is summarized and updated, and the prevalence, pathomechanism, prediction, prevention, treatment, and economic impact of hypersensitivity reactions are discussed. Particular attention is paid to the in vitro and in vivo evidence supporting complement activation as an underlying cause of RCM reactions.

  8. Glioma cell dispersion is driven by α5 integrin-mediated cell-matrix and cell-cell interactions.

    PubMed

    Blandin, Anne-Florence; Noulet, Fanny; Renner, Guillaume; Mercier, Marie-Cécile; Choulier, Laurence; Vauchelles, Romain; Ronde, Philippe; Carreiras, Franck; Etienne-Selloum, Nelly; Vereb, Gyorgy; Lelong-Rebel, Isabelle; Martin, Sophie; Dontenwill, Monique; Lehmann, Maxime

    2016-07-01

    Glioblastoma multiform (GBM) is the most common and most aggressive primary brain tumor. The fibronectin receptor, α5 integrin is a pertinent novel therapeutic target. Despite numerous data showing that α5 integrin support tumor cell migration and invasion, it has been reported that α5 integrin can also limit cell dispersion by increasing cell-cell interaction. In this study, we showed that α5 integrin was involved in cell-cell interaction and gliomasphere formation. α5-mediated cell-cell cohesion limited cell dispersion from spheroids in fibronectin-poor microenvironment. However, in fibronectin-rich microenvironment, α5 integrin promoted cell dispersion. Ligand-occupied α5 integrin and fibronectin were distributed in fibril-like pattern at cell-cell junction of evading cells, forming cell-cell fibrillar adhesions. Activated focal adhesion kinase was not present in these adhesions but was progressively relocalized with α5 integrin as cell migrates away from the spheroids. α5 integrin function in GBM appears to be more complex than previously suspected. As GBM overexpressed fibronectin, it is most likely that in vivo, α5-mediated dissemination from the tumor mass overrides α5-mediated tumor cell cohesion. In this respect, α5-integrin antagonists may be useful to limit GBM invasion in brain parenchyma. PMID:27063097

  9. Chrysin suppresses mast cell-mediated allergic inflammation: Involvement of calcium, caspase-1 and nuclear factor-{kappa}B

    SciTech Connect

    Bae, Yunju; Lee, Soyoung; Kim, Sang-Hyun

    2011-07-01

    A great number of people are suffering from allergic inflammatory diseases such as asthma, atopic dermatitis, and sinusitis. Therefore discovery of drugs for the treatment of these diseases is an important subject in human health. Chrysin (5,7-dihydroxyflavone) is a natural flavonoid contained in propolis, blue passion flower, and fruits. Several studies reported that chrysin has beneficial effects including anti-tumor and anti-oxidant activities. The aim of the present study was to elucidate whether chrysin modulates the allergic inflammatory reaction and to study its possible mechanisms of action using mast cell-based in vitro and in vivo models. Chrysin inhibited immediate-type systemic hypersensitivity and serum histamine release. Chrysin attenuated immunoglobulin E-mediated local anaphylaxis. These inhibitory effects of chrysin on the systemic and local allergic reaction were more potent than cromolyn, a known anti-allergic drug. Chrysin reduced histamine release from mast cells. The inhibitory effect of chrysin on the histamine release was mediated by the modulation of intracellular calcium. In addition, chrysin decreased gene expression of pro-inflammatory cytokines such as, tumor necrosis factor-{alpha}, IL (interleukin)-1{beta}, IL-4, and IL-6 in mast cells. The inhibitory effect of chrysin on the pro-inflammatory cytokine was nuclear factor-{kappa}B and caspase-1 dependent. Our findings provide evidence that chrysin inhibits mast cell-derived allergic inflammatory reactions by blocking histamine release and pro-inflammatory cytokine expression, and suggest the mechanisms of action. Furthermore, in vivo and in vitro anti-allergic inflammatory effect of chrysin suggests a possible therapeutic application of this agent in allergic inflammatory diseases. - Research Highlights: > Discovery of drugs for the allergic inflammation is important in human health. > Chrysin is a natural flavonoid contained in propolis, blue passion flower, and fruits. > Chrysin

  10. Cancer cell glycocalyx mediates mechanotransduction and flow-regulated invasion.

    PubMed

    Qazi, Henry; Palomino, Rocio; Shi, Zhong-Dong; Munn, Lance L; Tarbell, John M

    2013-11-01

    Mammalian cells are covered by a surface proteoglycan (glycocalyx) layer, and it is known that blood vessel-lining endothelial cells use the glycocalyx to sense and transduce the shearing forces of blood flow into intracellular signals. Tumor cells in vivo are exposed to forces from interstitial fluid flow that may affect metastatic potential but are not reproduced by most in vitro cell motility assays. We hypothesized that glycocalyx-mediated mechanotransduction of interstitial flow shear stress is an un-recognized factor that can significantly enhance metastatic cell motility and play a role in augmentation of invasion. Involvement of MMP levels, cell adhesion molecules (CD44, α3 integrin), and glycocalyx components (heparan sulfate and hyaluronan) was investigated in a cell/collagen gel suspension model designed to mimic the interstitial flow microenvironment. Physiological levels of flow upregulated MMP levels and enhanced the motility of metastatic cells. Blocking the flow-enhanced expression of MMP activity or adhesion molecules (CD44 and integrins) resulted in blocking the flow-enhanced migratory activity. The presence of a glycocalyx-like layer was verified around tumor cells, and the degradation of this layer by hyaluronidase and heparinase blocked the flow-regulated invasion. This study shows for the first time that interstitial flow enhancement of metastatic cell motility can be mediated by the cell surface glycocalyx - a potential target for therapeutics.

  11. Barium inhibits arsenic-mediated apoptotic cell death in human squamous cell carcinoma cells.

    PubMed

    Yajima, Ichiro; Uemura, Noriyuki; Nizam, Saika; Khalequzzaman, Md; Thang, Nguyen D; Kumasaka, Mayuko Y; Akhand, Anwarul A; Shekhar, Hossain U; Nakajima, Tamie; Kato, Masashi

    2012-06-01

    Our fieldwork showed more than 1 μM (145.1 μg/L) barium in about 3 μM (210.7 μg/L) arsenic-polluted drinking well water (n = 72) in cancer-prone areas in Bangladesh, while the mean concentrations of nine other elements in the water were less than 3 μg/L. The types of cancer include squamous cell carcinomas (SCC). We hypothesized that barium modulates arsenic-mediated biological effects, and we examined the effect of barium (1 μM) on arsenic (3 μM)-mediated apoptotic cell death of human HSC-5 and A431 SCC cells in vitro. Arsenic promoted SCC apoptosis with increased reactive oxygen species (ROS) production and JNK1/2 and caspase-3 activation (apoptotic pathway). In contrast, arsenic also inhibited SCC apoptosis with increased NF-κB activity and X-linked inhibitor of apoptosis protein (XIAP) expression level and decreased JNK activity (antiapoptotic pathway). These results suggest that arsenic bidirectionally promotes apoptotic and antiapoptotic pathways in SCC cells. Interestingly, barium in the presence of arsenic increased NF-κB activity and XIAP expression and decreased JNK activity without affecting ROS production, resulting in the inhibition of the arsenic-mediated apoptotic pathway. Since the anticancer effect of arsenic is mainly dependent on cancer apoptosis, barium-mediated inhibition of arsenic-induced apoptosis may promote progression of SCC in patients in Bangladesh who keep drinking barium and arsenic-polluted water after the development of cancer. Thus, we newly showed that barium in the presence of arsenic might inhibit arsenic-mediated cancer apoptosis with the modulation of the balance between arsenic-mediated promotive and suppressive apoptotic pathways.

  12. Intratumoral oxygen gradients mediate sarcoma cell invasion.

    PubMed

    Lewis, Daniel M; Park, Kyung Min; Tang, Vitor; Xu, Yu; Pak, Koreana; Eisinger-Mathason, T S Karin; Simon, M Celeste; Gerecht, Sharon

    2016-08-16

    Hypoxia is a critical factor in the progression and metastasis of many cancers, including soft tissue sarcomas. Frequently, oxygen (O2) gradients develop in tumors as they grow beyond their vascular supply, leading to heterogeneous areas of O2 depletion. Here, we report the impact of hypoxic O2 gradients on sarcoma cell invasion and migration. O2 gradient measurements showed that large sarcoma mouse tumors (>300 mm(3)) contain a severely hypoxic core [≤0.1% partial pressure of O2 (pO2)] whereas smaller tumors possessed hypoxic gradients throughout the tumor mass (0.1-6% pO2). To analyze tumor invasion, we used O2-controllable hydrogels to recreate the physiopathological O2 levels in vitro. Small tumor grafts encapsulated in the hydrogels revealed increased invasion that was both faster and extended over a longer distance in the hypoxic hydrogels compared with nonhypoxic hydrogels. To model the effect of the O2 gradient accurately, we examined individual sarcoma cells embedded in the O2-controllable hydrogel. We observed that hypoxic gradients guide sarcoma cell motility and matrix remodeling through hypoxia-inducible factor-1α (HIF-1α) activation. We further found that in the hypoxic gradient, individual cells migrate more quickly, across longer distances, and in the direction of increasing O2 tension. Treatment with minoxidil, an inhibitor of hypoxia-induced sarcoma metastasis, abrogated cell migration and matrix remodeling in the hypoxic gradient. Overall, we show that O2 acts as a 3D physicotactic agent during sarcoma tumor invasion and propose the O2-controllable hydrogels as a predictive system to study early stages of the metastatic process and therapeutic targets. PMID:27486245

  13. Doxorubicin-mediated Apoptosis in Glioma Cells Requires NFAT3

    PubMed Central

    Gopinath, Sreelatha; Vanamala, Sravan K.; Gujrati, Meena; Klopfenstein, Jeffrey D.; Dinh, Dzung H.; Rao, Jasti S.

    2009-01-01

    Nuclear Factor of Activated T cells (NFAT), a family of transcription factors, has been implicated in many cellular processes, including some cancers. For the first time, the present study characterizes the role of NFAT3 in doxorubicin (DOX) mediated apoptosis, migration, and invasion in SNB19 and U87 glioma cells. This study demonstrates specific knockdown of NFAT3 results in a dramatic inhibition of the apoptotic effect, induced by DOX, and favors cell survival. Inhibition of NFAT3 activation by shNFAT3 (shNF3) significantly downregulated TNF-α induction, its receptor TNFR1, caspase 10, caspase 3 and PARP, abrogating DOX-mediated apoptosis in glioma cells. DOX treatment resulted in NFAT3 translocation to the nucleus. Similarly, shNF3 treatment in SNB19 and U87 cells reversed DOX-induced inhibition of cell migration and invasion as determined by wound healing and matrigel invasion assays. Taken together, these results indicate that NFAT3 is a prerequisite for the induction of DOX-mediated apoptosis in glioma cells. PMID:19784808

  14. Clostridial Glucosylating Toxins Enter Cells via Clathrin-Mediated Endocytosis

    PubMed Central

    Genisyuerek, Selda; Guttenberg, Gregor; Aktories, Klaus

    2010-01-01

    Clostridium difficile toxin A (TcdA) and toxin B (TcdB), C. sordellii lethal toxin (TcsL) and C. novyi α-toxin (TcnA) are important pathogenicity factors, which represent the family of the clostridial glucosylating toxins (CGTs). Toxin A and B are associated with antibiotic-associated diarrhea and pseudomembraneous colitis. Lethal toxin is involved in toxic shock syndrome after abortion and α-toxin in gas gangrene development. CGTs enter cells via receptor-mediated endocytosis and require an acidified endosome for translocation of the catalytic domain into the cytosol. Here we studied the endocytic processes that mediate cell internalization of the CGTs. Intoxication of cells was monitored by analyzing cell morphology, status of Rac glucosylation in cell lysates and transepithelial resistance of cell monolayers. We found that the intoxication of cultured cells by CGTs was strongly delayed when cells were preincubated with dynasore, a cell-permeable inhibitor of dynamin, or chlorpromazine, an inhibitor of the clathrin-dependent endocytic pathway. Additional evidence about the role of clathrin in the uptake of the prototypical CGT family member toxin B was achieved by expression of a dominant-negative inhibitor of the clathrin-mediated endocytosis (Eps15 DN) or by siRNA against the clathrin heavy chain. Accordingly, cells that expressed dominant-negative caveolin-1 were not protected from toxin B-induced cell rounding. In addition, lipid rafts impairment by exogenous depletion of sphingomyelin did not decelerate intoxication of HeLa cells by CGTs. Taken together, our data indicate that the endocytic uptake of the CGTs involves a dynamin-dependent process that is mainly governed by clathrin. PMID:20498856

  15. Cell mediated immunity to fungi: a reassessment.

    PubMed

    Romani, Luigina

    2008-09-01

    Protective immunity against fungal pathogens is achieved by the integration of two distinct arms of the immune system, the innate and adaptive responses. Innate and adaptive immune responses are intimately linked and controlled by sets of molecules and receptors that act to generate the most effective form of immunity for protection against fungal pathogens. The decision of how to respond will still be primarily determined by interactions between pathogens and cells of the innate immune system, but the actions of T cells will feed back into this dynamic equilibrium to regulate the balance between tolerogenic and inflammatory responses. In the last two decades, the immunopathogenesis of fungal infections and fungal diseases was explained primarily in terms of Th1/Th2 balance. Although Th1 responses driven by the IL-12/IFN-gamma axis are central to protection against fungi, other cytokines and T cell-dependent pathways have come of age. The newly described Th17 developmental pathway may play an inflammatory role previously attributed to uncontrolled Th1 responses and serves to accommodate the seemingly paradoxical association of chronic inflammatory responses with fungal persistence in the face of an ongoing inflammation. Regulatory T cells in their capacity to inhibit aspects of innate and adaptive antifungal immunity have become an integral component of immune resistance to fungi, and provide the host with immune defense mechanisms adequate for protection, without necessarily eliminating fungal pathogens which would impair immune memory--or causing an unacceptable level of tissue damage. The enzyme indoleamine 2,3-dioxygenase and tryptophan metabolites contribute to immune homeostasis by inducing Tregs and taming overzealous or heightened inflammatory responses.

  16. Biomarkers of CD4+ CTL cell Mediated Immunity to Tuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The immune responses mediated by interactions between T-lymphocyte subsets and mycobacteria-infected macrophages are critical for control of tuberculosis. In these studies, the bovine model was used to characterize the cytolytic and mycobactericidal CD4+ T cell response induced by BCG vaccination. ...

  17. [Studies on the cell-mediated immunity in experimental Naegleria spp. infections].

    PubMed

    Lee, S G; Shin, H J; Im, K I

    1989-09-01

    Observations were made on the differences in cell-mediated immune responses in the mice infected with strongly pathogenic Naegleria fowleri ITMAP 359, weakly pathogenic Naegleria jadini 0400, or non-pathogenic Naegleria gruberi EGB, respectively. Variations in cell-mediated responses and changes in antibody titers according to the duration after infection were noted. Infections were done by dropping 5 microliters saline suspension containing 10 x 10(4) trophozoites cultured axenically in the CGVS medium into the right nasal cavity of ICR mice aging about 6-7 weeks, under the anesthesia by intraperitoneal injection of secobarbital. Following infection, delayed type hypersensitivity(DTH) responses in the footpad and blastogenic responses of the mouse spleen cells using [3H]-thymidine were observed on the day 1, 4, 7, 10 and 14 after infection. For the preparation of amoeba lysates, each of cultured trophozoites were homogenized with an ultrasonicator, and centrifugated at 20,000 g. The supernatants of amoeba lysates were used as the mitogen and antigen for ELISA. Concanavalin A(Con. A) and lipopolysaccharide(LPS) were also used as mitogens in the blastogenic response. 1. The mice infected with N. fowleri showed the mortality rate of 75.7%. The rate was 6.2% for the N. jadini infected group, while no dead mouse was observed for N. gruberi infections. 2. In regard to DTH responses in the N. fowleri infected mice, the level increased in comparison to the control group but declined after 7 days. An increase was also noted for the N. jadini group after 1 day, but gradual decreases were observed through the infection period. In addition, no difference was noted between the N. gruberi infected and control groups. 3. Concerning the blastogenic response of the splenocytes, it increased after 10 days in the experimental group of N. fowleri infection, but the differences were not statistically significant compared with control group. It was evident that N. jadini group was not

  18. Natural Killer Cell Mediated Cytotoxic Responses in the Tasmanian Devil

    PubMed Central

    Brown, Gabriella K.; Kreiss, Alexandre; Lyons, A. Bruce; Woods, Gregory M.

    2011-01-01

    The Tasmanian devil (Sarcophilus harrisii), the world's largest marsupial carnivore, is under threat of extinction following the emergence of an infectious cancer. Devil facial tumour disease (DFTD) is spread between Tasmanian devils during biting. The disease is consistently fatal and devils succumb without developing a protective immune response. The aim of this study was to determine if Tasmanian devils were capable of forming cytotoxic antitumour responses and develop antibodies against DFTD cells and foreign tumour cells. The two Tasmanian devils immunised with irradiated DFTD cells did not form cytotoxic or humoral responses against DFTD cells, even after multiple immunisations. However, following immunisation with xenogenic K562 cells, devils did produce cytotoxic responses and antibodies against this foreign tumour cell line. The cytotoxicity appeared to occur through the activity of natural killer (NK) cells in an antibody dependent manner. Classical NK cell responses, such as innate killing of DFTD and foreign cancer cells, were not observed. Cells with an NK-like phenotype comprised approximately 4 percent of peripheral blood mononuclear cells. The results of this study suggest that Tasmanian devils have NK cells with functional cytotoxic pathways. Although devil NK cells do not directly recognise DFTD cancer cells, the development of antibody dependent cell-mediated cytotoxicity presents a potential pathway to induce cytotoxic responses against the disease. These findings have positive implications for future DFTD vaccine research. PMID:21957452

  19. Ptch2 mediates the Shh response in Ptch1-/- cells.

    PubMed

    Alfaro, Astrid C; Roberts, Brock; Kwong, Lina; Bijlsma, Maarten F; Roelink, Henk

    2014-09-01

    The Hedgehog (Hh) signaling response is regulated by the interaction of three key components that include the sonic hedgehog (Shh) ligand, its receptor patched 1 (Ptch1) and the pathway activator smoothened (Smo). Under the prevailing model of Shh pathway activation, the binding of Shh to Ptch1 (the key Shh receptor) results in the release of Ptch1-mediated inhibition of Smo, leading to Smo activation and subsequent cell-autonomous activation of the Shh response. Consistent with this model, Ptch1(-/-) cells show a strong upregulation of the Shh response. Our finding that this response can be inhibited by the Shh-blocking antibody 5E1 indicates that the Shh response in Ptch1(-/-) cells remains ligand dependent. Furthermore, we find that Shh induces a strong response in Ptch1(-/-);Shh(-/-) cells, and that Ptch1(-/-) fibroblasts retain their ability to migrate towards Shh, demonstrating that Ptch1(-/-) cells remain sensitive to Shh. Expression of a dominant-negative Ptch1 mutant in the developing chick neural tube had no effect on Shh-mediated patterning, but expression of a dominant-negative form of patched 2 (Ptch2) caused an activation of the Shh response. This indicates that, at early developmental stages, Ptch2 functions to suppress Shh signaling. We found that Ptch1(-/-);Ptch2(-/-) cells cannot further activate the Shh response, demonstrating that Ptch2 mediates the response to Shh in the absence of Ptch1. PMID:25085974

  20. Mast Cell-Derived Histamine Mediates Cystitis Pain

    PubMed Central

    Rudick, Charles N.; Bryce, Paul J.; Guichelaar, Laura A.; Berry, Ruth E.; Klumpp, David J.

    2008-01-01

    Background Mast cells trigger inflammation that is associated with local pain, but the mechanisms mediating pain are unclear. Interstitial cystitis (IC) is a bladder disease that causes debilitating pelvic pain of unknown origin and without consistent inflammation, but IC symptoms correlate with elevated bladder lamina propria mast cell counts. We hypothesized that mast cells mediate pelvic pain directly and examined pain behavior using a murine model that recapitulates key aspects of IC. Methods and Findings Infection of mice with pseudorabies virus (PRV) induces a neurogenic cystitis associated with lamina propria mast cell accumulation dependent upon tumor necrosis factor alpha (TNF), TNF-mediated bladder barrier dysfunction, and pelvic pain behavior, but the molecular basis for pelvic pain is unknown. In this study, both PRV-induced pelvic pain and bladder pathophysiology were abrogated in mast cell-deficient mice but were restored by reconstitution with wild type bone marrow. Pelvic pain developed normally in TNF- and TNF receptor-deficient mice, while bladder pathophysiology was abrogated. Conversely, genetic or pharmacologic disruption of histamine receptor H1R or H2R attenuated pelvic pain without altering pathophysiology. Conclusions These data demonstrate that mast cells promote cystitis pain and bladder pathophysiology through the separable actions of histamine and TNF, respectively. Therefore, pain is independent of pathology and inflammation, and histamine receptors represent direct therapeutic targets for pain in IC and other chronic pain conditions. PMID:18461160

  1. Environmental Estrogens Induce Mast Cell Degranulation and Enhance IgE-Mediated Release of Allergic Mediators

    PubMed Central

    Narita, Shin-ichiro; Goldblum, Randall M.; Watson, Cheryl S.; Brooks, Edward G.; Estes, D. Mark; Curran, Edward M.; Midoro-Horiuti, Terumi

    2007-01-01

    Background Prevalence and morbidity of allergic diseases have increased over the last decades. Based on the recently recognized differences in asthma prevalence between the sexes, we have examined the effect of endogenous estrogens on a key element of the allergic response. Some lipophilic pollutants have estrogen-like activities and are termed environmental estrogens. These pollutants tend to degrade slowly in the environment and to bioaccumulate and bioconcentrate in the food chain; they also have long biological half-lives. Objectives Our goal in this study was to identify possible pathogenic roles for environmental estrogens in the development of allergic diseases. Methods We screened a number of environmental estrogens for their ability to modulate the release of allergic mediators from mast cells. We incubated a human mast cell line and primary mast cell cultures derived from bone marrow of wild type and estrogen receptor α (ER-α )–deficient mice with environmental estrogens with and without estradiol or IgE and allergens. We assessed degranulation of mast cells by quantifying the release of β -hexosaminidase. Results All of the environmental estrogens tested caused rapid, dose-related release of β -hexosaminidase from mast cells and enhanced IgE-mediated release. The combination of physiologic concentrations of 17β -estradiol and several concentrations of environmental estrogens had additive effects on mast cell degranulation. Comparison of bone marrow mast cells from ER-α –sufficient and ER-α –deficient mice indicated that much of the effect of environmental estrogens was mediated by ER-α . Conclusions Our findings suggest that estrogenic environmental pollutants might promote allergic diseases by inducing and enhancing mast cell degranulation by physiologic estrogens and exposure to allergens. PMID:17366818

  2. Evaluation of a spontaneous canine model of immunoglobulin E-mediated food hypersensitivity: dynamic changes in serum and fecal allergen-specific immunoglobulin E values relative to dietary change.

    PubMed

    Jackson, Hilary A; Hammerberg, Bruce

    2002-08-01

    The purpose of the pilot study reported here was to evaluate serum and fecal total and allergen-specific immunoglobulin E (IgE) responses to dietary change in five Maltese x beagle dogs with suspected food hypersensitivity, compared with those of five clinically normal dogs. Clinical parameters (pruritus, otitis, and diarrhea) improved in the Maltese x beagle dogs during feeding of a novel diet, and signs were exacerbated by oral allergen provocation. Relative concentrations of serum and fecal wheat-, corn-, and milk-specific IgE were determined by use of an ELISA. The onset of clinical signs of disease was accompanied by an increase in serum allergen-specific IgE concentrations. In contrast, changes in clinical signs of disease or allergen-specific IgE values were not seen in the control group undergoing the same regimen. Total serum IgE concentration was measured by use of the ELISA, and comparison with known quantities of a monoclonal IgE allowed absolute values to be reported. Values were high in the Maltese x beagle colony (7 to 34 microg/ml), compared with those in the control dogs (0.7 to 6 microg/ml). Total serum and total fecal IgE concentrations did not change in either group during the study. Although allergen-specific IgE was detected in the feces of both groups, significant interassay variability made interpretation of the results difficult. The authors concluded that these Maltese x beagle dogs satisfied the currently recognized clinical criteria for the diagnosis of canine food hypersensitivity. Furthermore, the clinical and serologic responses seen in these dogs in response to oral allergen provocation suggest that this may be a useful model for the study of spontaneous food hypersensitivity.

  3. Cell-Cell Interactions Mediate the Response of Vascular Smooth Muscle Cells to Substrate Stiffness

    PubMed Central

    Sazonova, Olga V.; Lee, Kristen L.; Isenberg, Brett C.; Rich, Celeste B.; Nugent, Matthew A.; Wong, Joyce Y.

    2011-01-01

    The vessel wall experiences progressive stiffening with age and the development of cardiovascular disease, which alters the micromechanical environment experienced by resident vascular smooth muscle cells (VSMCs). In vitro studies have shown that VSMCs are sensitive to substrate stiffness, but the exact molecular mechanisms of their response to stiffness remains unknown. Studies have also shown that cell-cell interactions can affect mechanotransduction at the cell-substrate interface. Using flexible substrates, we show that the expression of proteins associated with cell-matrix adhesion and cytoskeletal tension is regulated by substrate stiffness, and that an increase in cell density selectively attenuates some of these effects. We also show that cell-cell interactions exert a strong effect on cell morphology in a substrate-stiffness dependent manner. Collectively, the data suggest that as VSMCs form cell-cell contacts, substrate stiffness becomes a less potent regulator of focal adhesion signaling. This study provides insight into the mechanisms by which VSMCs respond to the mechanical environment of the blood vessel wall, and point to cell-cell interactions as critical mediators of VSMC response to vascular injury. PMID:21806930

  4. Single cell migration dynamics mediated by geometric confinement.

    PubMed

    Zhang, Hua; Hou, Ruixia; Xiao, Peng; Xing, Rubo; Chen, Tao; Han, Yanchun; Ren, Penggang; Fu, Jun

    2016-09-01

    The migration dynamics of cells plays a key role in tissue engineering and regenerative medicine. Previous studies mostly focus on regulating stem cell fate and phenotype by biophysical cues. In contrast, less is known about how the geometric cues mediate the migration dynamics of cells. Here, we fabricate graphene oxide (GO) microstripes on cell non-adhesive PEG substrate by using micromolding in capillary (MIMIC) method. Such micropatterns with alternating cell adhesion and cell resistance enable an effective control of selective adhesion and migration of single cells. The sharp contrast in cell adhesion minimizes the invasion of cells into the PEG patterns, and thereby strongly confines the cells on GO microstripes. As a result, the cells are forced to adapt highly polarized, elongated, and oriented geometry to fit the patterns. A series of pattern widths have been fabricated to modulate the extent of cell deformation and polarization. Under strong confinement, the cytoskeleton contractility, intracellular traction, and actin filament elongation are highly promoted, which result in enhanced cell migration along the patterns. This work provides an important insight into developing combinatorial graphene-based patterns for the control of cell migration dynamics, which is of great significance for tissue engineering and regenerative medicine. PMID:27137805

  5. Seasonal trade-offs in cell-mediated immunosenescence in ruffs (Philomachus pugnax).

    PubMed Central

    Lozano, George A; Lank, David B

    2003-01-01

    The immune system is an energetically expensive self-maintenance complex that, given the risks of parasitism, cannot be carelessly compromised. Life-history theory posits that trade-offs between fitness components, such as self-maintenance and reproduction, vary between genders and age classes depending on their expected residual lifetime reproductive success, and seasonally as energetic requirements change. Using ruff (Philomachus pugnax), a bird with two genetically distinct male morphs, we demonstrate here a decrease in male immunocompetence during the breeding season, greater variance in immune response among males than females, immunosenescence in both sexes and male morphs, and a seasonal shift in the age range required to detect senescence. Using a phytohaemagglutinin delayed hypersensitivity assay, we assessed cell-mediated immunity (CMI) of males of typical breeding age during the breeding and nonbreeding seasons, and of a larger sample that included females and birds of a greater age range during the non-breeding period. CMI was higher for breeding-aged males in May than in November, but the increase was not related to age or male morph. In November, mean CMI did not differ between the sexes, but the variance was higher for males than for females, and there were no differences in mean or variance between the two male morphs. For both sexes and male morphs, CMI was lower for young birds than for birds of typical breeding ages, and it declined again for older birds. In males, senescence was detected in the non-breeding season only when very old birds were included. These results, generally consistent with expectations from life-history theory, indicate that the immune system can be involved in multifarious trade-offs within a yearly cycle and along an individual's lifetime, and that specific predictions about means and variances in immune response should be considered in future immunoecological research. PMID:12816660

  6. Hypersensitivity pneumonitis during minocycline treatment.

    PubMed

    Kloppenburg, M; Dijkmans, B A; Breedveld, F C

    1994-06-01

    A patient is reported who developed dyspnoea, fever, pleuritic chest pain and a non-productive cough following treatment with minocycline for 9 days. The chest radiograph showed an interstitial pattern and there was a peripheral eosinophilia. A diagnosis of hypersensitivity pneumonitis attributable to minocycline was made. The disease responded quickly to withdrawal of the drug. This observation shows that minocycline, despite its mild toxicity profile, can give rise to serious adverse effects.

  7. Vaccination with a purified blood-stage malaria antigen in mice: correlation of protection with T cell mediated immunity.

    PubMed Central

    Playfair, J H; De Souza, J B; Freeman, R R; Holder, A A

    1985-01-01

    A purified 230,000 mol wt protein antigen from the lethal mouse malaria parasite Plasmodium yoelii YM which had previously been shown to be highly effective as a vaccine, was tested for its ability to stimulate specific helper T cells and T cells responsible for delayed hypersensitivity. Strong stimulation was found in both assays, but larger doses were required for delayed hypersensitivity, correlating well with the requirements for protection. It is suggested that T stimulation may be a requirement for effective protection by purified antigens in malaria. PMID:2933196

  8. Cytolysis of oligodendrocytes is mediated by killer (K) cells but not by natural killer (NK) cells.

    PubMed

    Satoh, J; Kim, S U; Kastrukoff, L F

    1991-03-01

    The cytotoxic activity of killer (K) cells against enriched cultures of bovine oligodendrocytes (BOL) was investigated in multiple sclerosis (MS) and controls. Human K cells mediated cytotoxicity to primary cultures of BOL in the presence of anti-BOL antiserum in all study groups, while BOL were resistant to human natural killer (NK) cells. Cytotoxic activity was significantly reduced in MS when compared to age-matched normal controls but not when compared to other neurologic disease (OND) patients. K cell-mediated lysis of BOL could also be induced with anti-galactocerebroside antibody but not with other antibodies including those specific for OL antigens (myelin basic protein, proteolipid apoprotein, and 2',3'-cyclic nucleotide 3'-phosphodiesterase). Enrichment of the effector population indicated that antibody-dependent cell-mediated cytotoxicity (ADCC) to BOL was mediated by large granular lymphocytes, and the effector population was further characterized by flow cytometry. The effector cells mediating ADCC could be inhibited by protein A of Staphylococcus aureus, and by K562 cells in cold competition assay. These observations indicate that oligodendrocytes are resistant to NK cells but are susceptible to cytolysis mediated by K cells. This may represent a potentially important immune mechanism in the pathogenesis of MS.

  9. MAR characteristic motifs mediate episomal vector in CHO cells.

    PubMed

    Lin, Yan; Li, Zhaoxi; Wang, Tianyun; Wang, Xiaoyin; Wang, Li; Dong, Weihua; Jing, Changqin; Yang, Xianjun

    2015-04-01

    An ideal gene therapy vector should enable persistent transgene expression without limitations in safety and reproducibility. Recent researches' insight into the ability of chromosomal matrix attachment regions (MARs) to mediate episomal maintenance of genetic elements allowed the development of a circular episomal vector. Although a MAR-mediated engineered vector has been developed, little is known on which motifs of MAR confer this function during interaction with the host genome. Here, we report an artificially synthesized DNA fragment containing only characteristic motif sequences that served as an alternative to human beta-interferon matrix attachment region sequence. The potential of the vector to mediate gene transfer in CHO cells was investigated. The short synthetic MAR motifs were found to mediate episomal vector at a low copy number for many generations without integration into the host genome. Higher transgene expression was maintained for at least 4 months. In addition, MAR was maintained episomally and conferred sustained EGFP expression even in nonselective CHO cells. All the results demonstrated that MAR characteristic sequence-based vector can function as stable episomes in CHO cells, supporting long-term and effective transgene expression.

  10. Dscam-Mediated Cell Recognition Regulates Neural Circuit Formation

    PubMed Central

    Hattori, Daisuke; Millard, S. Sean; Wojtowicz, Woj M.; Zipursky, S. Lawrence

    2009-01-01

    The Dscam family of immunoglobulin cell surface proteins mediates recognition events between neurons that play an essential role in the establishment of neural circuits. The Drosophila Dscam1 locus encodes tens of thousands of cell surface proteins via alternative splicing. These isoforms exhibit exquisite isoform-specific binding in vitro that mediates homophilic repulsion in vivo. These properties provide the molecular basis for self-avoidance, an essential developmental mechanism that allows axonal and dendritic processes to uniformly cover their synaptic fields. In a mechanistically similar fashion, homophilic repulsion mediated by Drosophila Dscam2 prevents processes from the same class of cells from occupying overlapping synaptic fields through a process called tiling. Genetic studies in the mouse visual system support the view that vertebrate DSCAM also promotes both self-avoidance and tiling. By contrast, DSCAM and DSCAM-L promote layer-specific targeting in the chick visual system, presumably through promoting homophilic adhesion. The fly and mouse studies underscore the importance of homophilic repulsion in regulating neural circuit assembly, whereas the chick studies suggest that DSCA Mproteins may mediate a variety of different recognition events during wiring in a context-dependent fashion. PMID:18837673

  11. Laminin: a possible role as a mediator of natural cell-mediated functions

    SciTech Connect

    Laybourn, K.A.

    1986-01-01

    Natural Cell-mediated cytotoxicity is clearly important in regulating host response during tumorgenicity. Natural killer (NK), and Natural Cytotoxic (NC) lymphocytes responsible for mediating cytolysis, are subpopulations of non-B, non-T, nonphagocytic, nonadherent lymphocytes capable of spontaneously lysing a variety of tumor targets. Evidence is presented that laminin, a high molecular weight glycoprotein, is present on the surface of murine NK cells. In addition, NK sensitive tumor targets are able to bind laminin. This suggest that laminin participates as a ligand in the binding of NK cells to their tumor targets. The saturable binding of laminin by NK and NC sensitive tumor targets was shown by laminin-induced cell-cell aggregation/adherence, and /sup 125/I-laminin binding studies. Exogenous laminin inhibited NK cytotoxicity but not CTL cytotoxicity in vitro. In comparison, NK-resistant tumor cells bound little, if any exogenous laminin. Modulating NK activity in vivo prior to challenging mice with an inoculation of a murine fibrosarcoma, showed that elimination or activation of NK activity resulted in an increase or decrease in pulmonary metastases, respectively.

  12. Carbonic anhydrase enzymes regulate mast cell-mediated inflammation.

    PubMed

    Henry, Everett K; Sy, Chandler B; Inclan-Rico, Juan M; Espinosa, Vanessa; Ghanny, Saleena S; Dwyer, Daniel F; Soteropoulos, Patricia; Rivera, Amariliz; Siracusa, Mark C

    2016-08-22

    Type 2 cytokine responses are necessary for the development of protective immunity to helminth parasites but also cause the inflammation associated with allergies and asthma. Recent studies have found that peripheral hematopoietic progenitor cells contribute to type 2 cytokine-mediated inflammation through their enhanced ability to develop into mast cells. In this study, we show that carbonic anhydrase (Car) enzymes are up-regulated in type 2-associated progenitor cells and demonstrate that Car enzyme inhibition is sufficient to prevent mouse mast cell responses and inflammation after Trichinella spiralis infection or the induction of food allergy-like disease. Further, we used CRISPR/Cas9 technology and illustrate that genetically editing Car1 is sufficient to selectively reduce mast cell development. Finally, we demonstrate that Car enzymes can be targeted to prevent human mast cell development. Collectively, these experiments identify a previously unrecognized role for Car enzymes in regulating mast cell lineage commitment and suggest that Car enzyme inhibitors may possess therapeutic potential that can be used to treat mast cell-mediated inflammation. PMID:27526715

  13. M-cadherin-mediated intercellular interactions activate satellite cell division.

    PubMed

    Marti, Merce; Montserrat, Núria; Pardo, Cristina; Mulero, Lola; Miquel-Serra, Laia; Rodrigues, Alexandre Miguel Cavaco; Andrés Vaquero, José; Kuebler, Bernd; Morera, Cristina; Barrero, María José; Izpisua Belmonte, Juan Carlos

    2013-11-15

    Adult muscle stem cells and their committed myogenic precursors, commonly referred to as the satellite cell population, are involved in both muscle growth after birth and regeneration after damage. It has been previously proposed that, under these circumstances, satellite cells first become activated, divide and differentiate, and only later fuse to the existing myofiber through M-cadherin-mediated intercellular interactions. Our data show that satellite cells fuse with the myofiber concomitantly to cell division, and only when the nuclei of the daughter cells are inside the myofiber, do they complete the process of differentiation. Here we demonstrate that M-cadherin plays an important role in cell-to-cell recognition and fusion, and is crucial for cell division activation. Treatment of satellite cells with M-cadherin in vitro stimulates cell division, whereas addition of anti-M-cadherin antibodies reduces the cell division rate. Our results suggest an alternative model for the contribution of satellite cells to muscle development, which might be useful in understanding muscle regeneration, as well as muscle-related dystrophies.

  14. Triggering of death receptor apoptotic signaling by human papillomavirus 16 E2 protein in cervical cancer cell lines is mediated by interaction with c-FLIP.

    PubMed

    Wang, Wei; Fang, Yong; Sima, Ni; Li, Yan; Li, Wei; Li, Li; Han, Linfei; Liao, Shujie; Han, Zhiqiang; Gao, Qinglei; Li, Kezhen; Deng, Dongrui; Meng, Li; Zhou, Jianfeng; Wang, Shixuan; Ma, Ding

    2011-01-01

    Human papillomavirus (HPV) E2 gene disruption is one of the key features of HPV-induced cervical malignant transformation. Though it is thought to prevent progression of carcinogenesis, the pro-apoptotic function of E2 protein remains poorly understood. This study shows that expression of HPV16 E2 induces apoptosis both in HPV-positive and -negative cervical cancer cell lines and leads to hyperactivation of caspase-8 and caspase-3. Activation of these signaling factors is responsible for the observed sensitivity to apoptosis upon treatment with anti-Fas antibody or TNF-α. In addition, immunoprecipitation experiments clearly show an interaction between HPV16 E2 and c-FLIP, a key regulator of apoptotic cell death mediated by death receptor signaling. Moreover, c-FLIP and a caspase-8 inhibitor protect cells from HPV16 E2-mediated apoptosis. Overexpression of c-FLIP rescues cervical cancer cells from apoptosis induced by HPV16 E2 protein expression. The data suggest that HPV16 E2 abrogates the apoptosis-inhibitory function of c-FLIP and renders the cell hypersensitive to the Fas/FasL apoptotic signal even below threshold concentration. This suggests a novel mechanism for deregulation of cervical epithelial cell growth upon HPV-induced transformation, which is of great significance in developing therapeutic strategies for intervention of cervical carcinogenesis.

  15. Estrogen-dependent visceral hypersensitivity following stress in rats

    PubMed Central

    Hubbard, Catherine S; Karpowicz, Jane M; Furman, Andrew J; da Silva, Joyce Teixeira; Traub, Richard J

    2016-01-01

    We used functional MRI and a longitudinal design to investigate the brain mechanisms in a previously reported estrogen-dependent visceral hypersensitivity model. We hypothesized that noxious visceral stimulation would be associated with activation of the insula, anterior cingulate cortex, and amygdala, and that estrogen-dependent, stress-induced visceral hypersensitivity would both enhance activation of these regions and recruit activation of other brain areas mediating affect and reward processing. Ovariectomized rats were treated with estrogen (17 β-estradiol, E2) or vehicle (n = 5 per group) and scanned in a 7T MRI at three different time points: pre-stress (baseline), 2 days post-stress, and 18 days post-stress. Stress was induced via a forced-swim paradigm. In a separate group of ovariectomized rats, E2 treatment induced visceral hypersensitivity at the 2 days post-stress time point, and this hypersensitivity returned to baseline at the 18 days post-stress time point. Vehicle-treated rats show no hypersensitivity following stress. During the MRI scans, rats were exposed to noxious colorectal distention. Across groups and time points, noxious visceral stimulation led to activations in the insula, anterior cingulate, and left amygdala, parabrachial nuclei, and cerebellum. A group-by-time interaction was seen in the right amygdala, ventral striatum-pallidum, cerebellum, hippocampus, mediodorsal thalamus, and pontine nuclei. Closer inspection of the data revealed that vehicle-treated rats showed consistent activations and deactivations across time, whereas estrogen-treated animals showed minimal deactivation with noxious visceral stimulation. This unexpected finding suggests that E2 may dramatically alter visceral nociceptive processing in the brain following an acute stressor. This study is the first to examine estrogen-stress dependent interactions in response to noxious visceral stimulation using functional MRI. Future studies that include other control

  16. TLR2-mediated Cell Stimulation in Bacterial Vaginosis

    PubMed Central

    Mares, Debra; Simoes, Jose A.; Novak, Richard M.; Spear, Gregory T.

    2008-01-01

    Bacterial vaginosis (BV) is associated with preterm labor, pelvic inflammatory disease and increased HIV acquisition, although the pathways that mediate these pathological effects have not been elucidated. To determine the presence of toll-like receptor (TLR)-ligands and their specificity in BV, genital tract fluids were collected from women with and without BV by cervicovaginal lavage (CVL). The CVL samples were evaluated for their ability to stimulate secretion of proinflammatory cytokines and to activate NF κB and the HIV long terminal repeat (LTR), indicators of TLR activation, in human monocytic cells. Stimulation with BV CVLs induced higher levels of IL-8 and TNFα secretion, as well as higher levels of HIV LTR and NF κB activation, than CVLs from women with normal healthy bacterial flora. To identify which TLRs were important in BV, 293 cells expressing specific TLRs were exposed to CVL samples. BV CVLs induced higher IL-8 secretion by cells expressing TLR2 than CVLs from women without BV. Surprisingly, BV CVLs did not stimulate cells expressing TLR4/MD2, although these cells responded to purified LPS, a TLR4 ligand. BV CVLs, in cells expressing TLR2, also activated the HIV LTR. Thus, these studies show that soluble factor(s) present in the lower genital tract of women with BV activate cells via TLR2, identifying a pathway through which BV may mediate adverse effects. PMID:17532476

  17. Lysophosphatidic acid mediates pleiotropic responses in skeletal muscle cells

    SciTech Connect

    Jean-Baptiste, Gael; Yang Zhao; Khoury, Chamel; Greenwood, Michael T.; E-mail: michael.greenwood@mcgill.ca

    2005-10-07

    Lysophosphatidic acid (LPA) is a potent modulator of growth, cell survival, and apoptosis. Although all four LPA receptors are expressed in skeletal muscle, very little is known regarding the role they play in this tissue. We used RT-PCR to demonstrate that cultured skeletal muscle C2C12 cells endogenously express multiple LPA receptor subtypes. The demonstration that LPA mediates the activation of ERK1/2 MAP kinase and Akt/PKB in C2C12 cells is consistent with the widely observed mitogenic properties of LPA. In spite of these observations, LPA did not induce proliferation in C2C12 cells. Paradoxically, we found that prolonged treatment of C2C12 cells with LPA led to caspase 3 and PARP cleavage as well as the activation of stress-associated MAP kinases JNK and p38. In spite of these typically pro-apoptotic responses, LPA did not induce cell death. Blocking ERK1/2 and Akt/PKB activation with specific pharmacological inhibitors, nevertheless, stimulated LPA-mediated apoptosis. Taken together, these results suggest that both mitogenic and apoptotic responses serve to counterbalance the effects of LPA in cultured C2C12 cells.

  18. Acceptor sites for retroviral integrations map near DNase I-hypersensitive sites in chromatin.

    PubMed Central

    Vijaya, S; Steffen, D L; Robinson, H L

    1986-01-01

    Seven cellular loci with acceptor sites for retroviral integrations have been mapped for the presence of DNase I-hypersensitive sites in chromatin. Integrations in three of these loci, chicken c-erbB, rat c-myc, and a rat locus, dsi-1, had been selected for in retrovirus-induced tumors. Of the remaining four, two, designated dsi-3 and dsi-4, harbored acceptor sites for apparently unselected integrations of Moloney murine leukemia virus in a Moloney murine leukemia virus-induced thymoma, and two, designated C and F, harbored unselected acceptor sites for Moloney murine leukemia virus integrations in a rat fibroblast cell line. Each acceptor site mapped to within 500 base pairs of a DNase I-hypersensitive site. In the analyses of the unselected integrations, six hypersensitive sites were observed in 39 kilobases of DNA. The four acceptor sites in this DNA were localized between 0.05 and 0.43 kilobases of a hypersensitive site. The probability of this close association occurring by chance was calculated to be extremely low. Hypersensitive sites were mapped in cells representing the lineage in which integration had occurred as well as in an unrelated lineage. In six of the seven acceptor loci hypersensitive sites could not be detected in the unrelated lineage. Our results indicate that retroviruses preferentially integrate close to DNase I-hypersensitive sites and that many of these sites are expressed in some but not all cells. Images PMID:3490582

  19. Identification of novel pepper genes involved in Bax- or INF1-mediated cell death responses by high-throughput virus-induced gene silencing.

    PubMed

    Lee, Jeong Hee; Kim, Young Cheol; Choi, Doil; Park, Jeong Mee

    2013-11-19

    Hot pepper is one of the economically important crops in Asia. A large number of gene sequences, including expressed sequence tag (EST) and genomic sequences are publicly available. However, it is still a daunting task to determine gene function due to difficulties in genetic modification of a pepper plants. Here, we show the application of the virus-induced gene silencing (VIGS) repression for the study of 459 pepper ESTs selected as non-host pathogen-induced cell death responsive genes from pepper microarray experiments in Nicotiana benthamiana. Developmental abnormalities in N. benthamiana plants are observed in the 32 (7%) pepper ESTs-silenced plants. Aberrant morphological phenotypes largely comprised of three groups: stunted, abnormal leaf, and dead. In addition, by employing the combination of VIGS and Agrobacterium-mediated transient assays, we identified novel pepper ESTs that involved in Bax or INF1-mediated cell death responses. Silencing of seven pepper ESTs homologs suppressed Bax or INF1-induced cell death, five of which suppressed both cell death responses in N. benthamiana. The genes represented by these five ESTs encode putative proteins with functions in endoplasmic reticulum (ER) stress and lipid signaling. The genes represented by the other two pepper ESTs showing only Bax-mediated cell death inhibition encode a CCCH-type zinc finger protein containing an ankyrin-repeat domain and a probable calcium-binding protein, CML30-like. Taken together, we effectively isolated novel pepper clones that are involved in hypersensitive response (HR)-like cell death using VIGS, and identified silenced clones that have different responses to Bax and INF1 exposure, indicating separate signaling pathways for Bax- and INF1-mediated cell death.

  20. Photoreceptor Cells Produce Inflammatory Mediators That Contribute to Endothelial Cell Death in Diabetes

    PubMed Central

    Tonade, Deoye; Liu, Haitao; Kern, Timothy S.

    2016-01-01

    Purpose Recent studies suggest that photoreceptor cells regulate local inflammation in the retina in diabetes. The purpose of this study was to determine if photoreceptor cells themselves produce inflammatory proteins in diabetes and if soluble factors released by photoreceptors in elevated glucose induce inflammatory changes in nearby cells. Methods Laser capture microdissection was used to isolate the outer retina (photoreceptors) from the inner retina in nondiabetic and diabetic mice. Diabetes-induced changes in the expression of inflammatory targets were assessed by reverse transcription polymerase chain reaction and immunohistochemistry. Cell culture experiments were carried out to determine if photoreceptors in vitro and ex vivo release soluble mediators that can stimulate nearby cells. Photoreceptor contribution to leukocyte-mediated endothelial cell death was tested using coculture models. Results Messenger ribonucleic acid and protein expression levels for inflammatory proteins intercellular adhesion molecule 1 (ICAM1), inducible nitric oxide synthase (iNOS), and cyclooxygenase 2 (COX2) were increased in photoreceptors cells in diabetes. In vitro and ex vivo studies show that photoreceptor cells in elevated glucose release mediators that can induce tumor necrosis factor-α in leukocytes and endothelial cells, but not in glia. The soluble mediators released by photoreceptor cells in elevated glucose are regulated by transforming growth factor β-activated kinase 1 and nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase) signaling. In contrast to enhanced leukocyte-mediated killing of endothelial cells by leukocytes from wild-type diabetic mice, leukocytes from diabetic mice lacking photoreceptor cells (opsin−/−) did not kill endothelial cells. Conclusions These data indicate that photoreceptor cells are a source of inflammatory proteins in diabetes, and their release of soluble mediators can contribute to the death of retinal capillaries

  1. Caspase-1 mediates hyperlipidemia-weakened progenitor cell vessel repair

    PubMed Central

    Li, Ya-Feng; Huang, Xiao; Li, Xinyuan; Gong, Ren; Yin, Ying; Nelson, Jun; Gao, Erhe; Zhang, Hongyu; Hoffman, Nicholas E.; Houser, Steven R.; Madesh, Muniswamy; Tilley, Douglas G.; Choi, Eric T.; Jiang, Xiaohua; Huang, Cong-Xin; Wang, Hong; Yang, Xiao-Feng

    2015-01-01

    Caspase-1 activation senses metabolic danger-associated molecular patterns (DAMPs) and mediates the initiation of inflammation in endothelial cells. Here, we examined whether the caspase-1 pathway is responsible for sensing hyperlipidemia as a DAMP in bone marrow (BM)-derived Stem cell antigen-1 positive (Sca-1+) stem/progenitor cells and weakening their angiogenic ability. Using biochemical methods, gene knockout, cell therapy and myocardial infarction (MI) models, we had the following findings: 1) Hyperlipidemia induces caspase-1 activity in mouse Sca-1+ progenitor cells in vivo; 2) Caspase-1 contributes to hyperlipidemia-induced modulation of vascular cell death-related gene expression in vivo; 3) Injection of Sca-1+ progenitor cells from caspase-1−/− mice improves endothelial capillary density in heart and decreases cardiomyocyte death in a mouse model of MI; and 4) Caspase-1−/− Sca-1+ progenitor cell therapy improves mouse cardiac function after MI. Our results provide insight on how hyperlipidemia activates caspase-1 in Sca-1+ progenitor cells, which subsequently weakens Sca-1+ progenitor cell repair of vasculature injury. These results demonstrate the therapeutic potential of caspase-1 inhibition in improving progenitor cell therapy for MI. PMID:26709768

  2. LOX-1-Mediated Effects on Vascular Cells in Atherosclerosis.

    PubMed

    Chistiakov, Dimitry A; Orekhov, Alexander N; Bobryshev, Yuri V

    2016-01-01

    In healthy arteries, expression of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is almost undetectable. However, in proatherogenic conditions, LOX-1 is markedly up-regulated in vascular cells. In atherosclerosis, LOX-1 appears to be the key scavenger receptor for binding oxidized LDL (oxLDL). Notably, a positive feedback exists between LOX-1 and oxLDL. LOX-1 is involved in mediating of proatherosclerotic effects of oxLDL which result in endothelial dysfunction, proinflammatory recruitment of monocytes into the arterial intima, formation of foam cells, apoptosis of endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), as well as in plaque destabilization and rupture. In this review, we consider effects of the LOX-1/oxLDL axis on several types of vascular cells such as ECs, VSMCs, and macrophages. PMID:27160316

  3. Defect-Mediated Morphologies in Growing Cell Colonies.

    PubMed

    Doostmohammadi, Amin; Thampi, Sumesh P; Yeomans, Julia M

    2016-07-22

    Morphological trends in growing colonies of living cells are at the core of physiological and evolutionary processes. Using active gel equations, which include cell division, we show that shape changes during the growth can be regulated by the dynamics of topological defects in the orientation of cells. The friction between the dividing cells and underlying substrate drives anisotropic colony shapes toward more isotropic morphologies, by mediating the number density and velocity of topological defects. We show that the defects interact with the interface at a specific interaction range, set by the vorticity length scale of flows within the colony, and that the cells predominantly reorient parallel to the interface due to division-induced active stresses. PMID:27494503

  4. Transcription factor-mediated reprogramming toward hematopoietic stem cells

    PubMed Central

    Ebina, Wataru; Rossi, Derrick J

    2015-01-01

    De novo generation of human hematopoietic stem cells (HSCs) from renewable cell types has been a long sought-after but elusive goal in regenerative medicine. Paralleling efforts to guide pluripotent stem cell differentiation by manipulating developmental cues, substantial progress has been made recently toward HSC generation via combinatorial transcription factor (TF)-mediated fate conversion, a paradigm established by Yamanaka's induction of pluripotency in somatic cells by mere four TFs. This review will integrate the recently reported strategies to directly convert a variety of starting cell types toward HSCs in the context of hematopoietic transcriptional regulation and discuss how these findings could be further developed toward the ultimate generation of therapeutic human HSCs. PMID:25712209

  5. Defect-Mediated Morphologies in Growing Cell Colonies

    NASA Astrophysics Data System (ADS)

    Doostmohammadi, Amin; Thampi, Sumesh P.; Yeomans, Julia M.

    2016-07-01

    Morphological trends in growing colonies of living cells are at the core of physiological and evolutionary processes. Using active gel equations, which include cell division, we show that shape changes during the growth can be regulated by the dynamics of topological defects in the orientation of cells. The friction between the dividing cells and underlying substrate drives anisotropic colony shapes toward more isotropic morphologies, by mediating the number density and velocity of topological defects. We show that the defects interact with the interface at a specific interaction range, set by the vorticity length scale of flows within the colony, and that the cells predominantly reorient parallel to the interface due to division-induced active stresses.

  6. Systemic cell-mediated reactions in vivo. Effect of the interaction of circulating antigen with sensitized lymphocytes on glomeruli and pulmonary alveoli.

    PubMed Central

    Bhan, A. K.; Schneeberger, E. E.; Collins, A. B.; McCluskey, R. T.

    1984-01-01

    The effects of systemic cell-mediated hypersensitivity reactions on glomeruli and lungs were investigated in rats. The animals were given an intravenous injection of antigen 7 days after sensitization or were given an intravenous injection of lymph node cells from sensitized syngeneic donors 1 day after antigen injection. Control animals were given an irrelevant antigen or saline. All animals received three injections of 3H-thymidine during the course of the experiments. The animals were sacrificed 2 or 3 days after antigen injection. Autoradiographs of renal and pulmonary tissue showed significantly more labeled mononuclear cells in glomeruli and pulmonary alveolar walls in the experimental groups than in the control groups. Immunofluorescence studies did not reveal antigen, rat IgG, or C3 in glomeruli. The results indicate that systemic cell-mediated reactions can lead to an accumulation of mononuclear cells in glomeruli and lungs, an effect that may contribute to tissue injury. Images Figure 1 Figure 2 Figure 3 PMID:6611090

  7. Chromatin remodeling by the SWI/SNF complex is essential for transcription mediated by the yeast cell wall integrity MAPK pathway.

    PubMed

    Sanz, A Belén; García, Raúl; Rodríguez-Peña, Jose Manuel; Díez-Muñiz, Sonia; Nombela, César; Peterson, Craig L; Arroyo, Javier

    2012-07-01

    In Saccharomyces cerevisiae, the transcriptional program triggered by cell wall stress is coordinated by Slt2/Mpk1, the mitogen-activated protein kinase (MAPK) of the cell wall integrity (CWI) pathway, and is mostly mediated by the transcription factor Rlm1. Here we show that the SWI/SNF chromatin-remodeling complex plays a critical role in orchestrating the transcriptional response regulated by Rlm1. swi/snf mutants show drastically reduced expression of cell wall stress-responsive genes and hypersensitivity to cell wall-interfering compounds. On stress, binding of RNA Pol II to the promoters of these genes depends on Rlm1, Slt2, and SWI/SNF. Rlm1 physically interacts with SWI/SNF to direct its association to target promoters. Finally, we observe nucleosome displacement at the CWI-responsive gene MLP1/KDX1, which relies on the SWI/SNF complex. Taken together, our results identify the SWI/SNF complex as a key element of the CWI MAPK pathway that mediates the chromatin remodeling necessary for adequate transcriptional response to cell wall stress.

  8. Single-cell force spectroscopy of pili-mediated adhesion

    NASA Astrophysics Data System (ADS)

    Sullan, Ruby May A.; Beaussart, Audrey; Tripathi, Prachi; Derclaye, Sylvie; El-Kirat-Chatel, Sofiane; Li, James K.; Schneider, Yves-Jacques; Vanderleyden, Jos; Lebeer, Sarah; Dufrêne, Yves F.

    2013-12-01

    Although bacterial pili are known to mediate cell adhesion to a variety of substrates, the molecular interactions behind this process are poorly understood. We report the direct measurement of the forces guiding pili-mediated adhesion, focusing on the medically important probiotic bacterium Lactobacillus rhamnosus GG (LGG). Using non-invasive single-cell force spectroscopy (SCFS), we quantify the adhesion forces between individual bacteria and biotic (mucin, intestinal cells) or abiotic (hydrophobic monolayers) surfaces. On hydrophobic surfaces, bacterial pili strengthen adhesion through remarkable nanospring properties, which - presumably - enable the bacteria to resist high shear forces under physiological conditions. On mucin, nanosprings are more frequent and adhesion forces larger, reflecting the influence of specific pili-mucin bonds. Interestingly, these mechanical responses are no longer observed on human intestinal Caco-2 cells. Rather, force curves exhibit constant force plateaus with extended ruptures reflecting the extraction of membrane nanotethers. These single-cell analyses provide novel insights into the molecular mechanisms by which piliated bacteria colonize surfaces (nanosprings, nanotethers), and offer exciting avenues in nanomedicine for understanding and controlling the adhesion of microbial cells (probiotics, pathogens).

  9. Free energy landscape of receptor-mediated cell adhesion

    NASA Astrophysics Data System (ADS)

    Yang, Tianyi; Zaman, Muhammad H.

    2007-01-01

    Receptor-mediated cell adhesion plays a critical role in cell migration, proliferation, signaling, and survival. A number of diseases, including cancer, show a strong correlation between integrin activation and metastasis. A better understanding of cell adhesion is highly desirable for not only therapeutic but also a number of tissue engineering applications. While a number of computational models and experimental studies have addressed the issue of cell adhesion to surfaces, no model or theory has adequately addressed cell adhesion at the molecular level. In this paper, the authors present a thermodynamic model that addresses receptor-mediated cell adhesion at the molecular level. By incorporating the entropic, conformational, solvation, and long- and short-range interactive components of receptors and the extracellular matrix molecules, they are able to predict adhesive free energy as a function of a number of key variables such as surface coverage, interaction distance, molecule size, and solvent conditions. Their method allows them to compute the free energy of adhesion in a multicomponent system where they can simultaneously study adhesion receptors and ligands of different sizes, chemical identities, and conformational properties. The authors' results not only provide a fundamental understanding of adhesion at the molecular level but also suggest possible strategies for designing novel biomaterials.

  10. Bipyridyl cobalt complex mediators in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Scott, Michael J.

    Dye-sensitization of semiconductor substrates allows for efficient charge injection into the semiconductor conduction band. Dye-sensitized solar cells (DSSCs) exploit this for conversion of light into electrical energy. By employing mesoporous TiO2 a significant portion of visible light can be absorbed. The mesoporous TiO2, deposited on a transparent conducting oxide (TCO) medium, constitutes the photoanode of the DSSC. A wide range of materials may be used as a cathode. A redox electrolyte solution completes the cell. Typically, the I-/I3- redox couple has been employed in DSSCs. The use of bipyridyl cobalt complexes allows for tuning of the cell's electrochemistry, exploration of diverse cathode materials, and investigation of mediator solution additives. Cobalt complexes with alkyl, ester, and amide functionalities were considered throughout this body of work. The cobalt complexes were investigated on the basis of time dependence and electrode dependence. The cobalt complexes are stable for at least a period of one week when dissolved in gamma-butyrolactone. Gold, carbon and modified TCO cathodes perform well in cells employing the alkyl substituted complex. Gold cathodes alone provide the best performance with cells employing the ester and amide substituted complex. An optically transparent cathode was developed for use in stacked DSSCs, allowing light that is not absorbed by the first DSSC in a stack to be absorbed by a second cell. A spectrally complementary dye in the second cell extends the light absorption to longer wavelengths. Spatial current images were obtained to investigate the local current behavior of cobalt mediated cells. Intentional electrode damage was visualized, and the effects of increased pressure on the cell were discussed. The use of phenothiazine (PTZ) moieties as co-mediators in cobalt mediated DSSCs was investigated. An anionic PTZ salt was most effective at reducing the photo-oxidized sensitizing dye. This PTZ salt enhanced the

  11. Hypersensitivity syndrome caused by amitriptyline administration

    PubMed Central

    Milionis, H.; Skopelitou, A.; Elisaf, M.

    2000-01-01

    Adverse cutaneous manifestations are among the most common side effects associated with psychotropic drugs. Skin reactions due to amitriptyline (a tricyclic antidepressant agent) include rashes and hypersensitivity reactions (for example, urticaria and photosensitivity) as well as hyperpigmentation. Hypersensitivity syndrome is a specific severe idiosyncratic reaction causing skin, liver, joint, and haematological abnormalities, which usually resolve after the discontinuation of the implicated drug. A case of a 24 year old woman who experienced hypersensitivity syndrome three weeks after the initiation of amitriptyline is reported.


Keywords: tricyclic antidepressant drugs; amitriptyline; adverse cutaneous reactions; hypersensitivity syndrome PMID:10824052

  12. Contribution of afferent pathways to nerve injury-induced spontaneous pain and evoked hypersensitivity.

    PubMed

    King, Tamara; Qu, Chaoling; Okun, Alec; Mercado, Ramon; Ren, Jiyang; Brion, Triza; Lai, Josephine; Porreca, Frank

    2011-09-01

    A predominant complaint in patients with neuropathic pain is spontaneous pain, often described as burning. Recent studies have demonstrated that negative reinforcement can be used to unmask spontaneous neuropathic pain, allowing for mechanistic investigations. Here, ascending pathways that might contribute to evoked and spontaneous components of an experimental neuropathic pain model were explored. Desensitization of TRPV1-positive fibers with systemic resiniferatoxin (RTX) abolished spinal nerve ligation (SNL) injury-induced thermal hypersensitivity and spontaneous pain, but had no effect on tactile hypersensitivity. Ablation of spinal NK-1 receptor-expressing neurons blocked SNL-induced thermal and tactile hypersensitivity as well as spontaneous pain. After nerve injury, upregulation of neuropeptide Y (NPY) is observed almost exclusively in large-diameter fibers, and inactivation of the brainstem target of these fibers in the nucleus gracilis prevents tactile but not thermal hypersensitivity. Blockade of NPY signaling within the nucleus gracilis failed to block SNL-induced spontaneous pain or thermal hyperalgesia while fully reversing tactile hypersensitivity. Moreover, microinjection of NPY into nucleus gracilis produced robust tactile hypersensitivity, but failed to induce conditioned place aversion. These data suggest that spontaneous neuropathic pain and thermal hyperalgesia are mediated by TRPV1-positive fibers and spinal NK-1-positive ascending projections. In contrast, the large-diameter dorsal column projection can mediate nerve injury-induced tactile hypersensitivity, but does not contribute to spontaneous pain. Because inhibition of tactile hypersensitivity can be achieved either by spinal manipulations or by inactivation of signaling within the nucleus gracilis, the enhanced paw withdrawal response evoked by tactile stimulation does not necessarily reflect allodynia.

  13. Cell-mediated immunity caused by beryllium compounds.

    PubMed

    Sakaguchi, S; Sakaguchi, T; Nakamura, I; Kudo, Y

    1987-11-01

    Cells of spleen and lymph nodes were obtained from mice subcutaneously injected with BeCl2 once a week over a 6-week period. These cells were washed twice in cold phosphate-buffered saline and suspended at a final concentration of 2 x 10(7) cells in 1 ml of buffer. Subsequently, 0.5 ml of the suspension was injected into normal mice intravenously (passive transfer). The findings of the experiments using these mice are summarized as follows: (1) The footpad reaction test was performed 24 hrs after passive transfer. The mice receiving spleen cells or lymph node cells from mice sensitized with BeCl2 developed significant footpad swelling 24 and 48 hrs after challenge of BeCl2 as the antigen. (2) After passive transfer with sensitized spleen cells or lymph node cells the ears of the mice were painted with 7% BeCl2 in ethyl alcohol. Ears of these mice showed significant swelling as compared with those of controls. (3) The migration of peritoneal cells from mice receiving spleen or lymph node cells from sensitized mice was inhibited when tested in medium containing the antigen of BeCl2. From our present experiments, it was suggested that the beryllium sensitizing ability was related to active as well as passive cell-mediated immunity.

  14. Effect of space flight on cell-mediated immunity

    NASA Technical Reports Server (NTRS)

    Mandel, A. D.; Balish, E.

    1977-01-01

    The cell-mediated immune response to Listeria monocytogenes was studied in rats subjected to 20 days of flight aboard the Soviet biosatellite Kosmos 7820. Groups of rats were immunized with 1,000,000 formalin-killed Listeria suspended in Freunds Complete Adjuvant, 5 days prior to flight. Immunized rats subjected to the same environmental factors as the flight rats, except flight itself, and immunized and nonimmunized rats held in a normal animal colony served as controls. Following recovery, lymphocyte cultures were harvested from spleens of all rats, cultured in vitro in the presence of L. monocytogenes antigens, Phytohemagglutinin, Conconavlin A, or purified protein derivative (PPD), and measured for their uptake of H-3-thymidine. Although individual rats varied considerably, all flight and immunized control rats gave a blastogenic response to the Listeria antigens and PPD. With several mitogens, the lymphocytes of flight rats showed a significantly increased blastogenic response over the controls. The results of this study do not support a hypothesis of a detrimental effect of space flight on cell-mediated immunity. The data suggest a possible suppressive effect of stress and gravity on an in vitro correlate of cell-mediated immunity.

  15. Fibronectin on the Surface of Myeloma Cell-derived Exosomes Mediates Exosome-Cell Interactions.

    PubMed

    Purushothaman, Anurag; Bandari, Shyam Kumar; Liu, Jian; Mobley, James A; Brown, Elizabeth E; Sanderson, Ralph D

    2016-01-22

    Exosomes regulate cell behavior by binding to and delivering their cargo to target cells; however, the mechanisms mediating exosome-cell interactions are poorly understood. Heparan sulfates on target cell surfaces can act as receptors for exosome uptake, but the ligand for heparan sulfate on exosomes has not been identified. Using exosomes isolated from myeloma cell lines and from myeloma patients, we identify exosomal fibronectin as a key heparan sulfate-binding ligand and mediator of exosome-cell interactions. We discovered that heparan sulfate plays a dual role in exosome-cell interaction; heparan sulfate on exosomes captures fibronectin, and on target cells it acts as a receptor for fibronectin. Removal of heparan sulfate from the exosome surface releases fibronectin and dramatically inhibits exosome-target cell interaction. Antibody specific for the Hep-II heparin-binding domain of fibronectin blocks exosome interaction with tumor cells or with marrow stromal cells. Regarding exosome function, fibronectin-mediated binding of exosomes to myeloma cells activated p38 and pERK signaling and expression of downstream target genes DKK1 and MMP-9, two molecules that promote myeloma progression. Antibody against fibronectin inhibited the ability of myeloma-derived exosomes to stimulate endothelial cell invasion. Heparin or heparin mimetics including Roneparstat, a modified heparin in phase I trials in myeloma patients, significantly inhibited exosome-cell interactions. These studies provide the first evidence that fibronectin binding to heparan sulfate mediates exosome-cell interactions, revealing a fundamental mechanism important for exosome-mediated cross-talk within tumor microenvironments. Moreover, these results imply that therapeutic disruption of fibronectin-heparan sulfate interactions will negatively impact myeloma tumor growth and progression. PMID:26601950

  16. Fibronectin on the Surface of Myeloma Cell-derived Exosomes Mediates Exosome-Cell Interactions.

    PubMed

    Purushothaman, Anurag; Bandari, Shyam Kumar; Liu, Jian; Mobley, James A; Brown, Elizabeth E; Sanderson, Ralph D

    2016-01-22

    Exosomes regulate cell behavior by binding to and delivering their cargo to target cells; however, the mechanisms mediating exosome-cell interactions are poorly understood. Heparan sulfates on target cell surfaces can act as receptors for exosome uptake, but the ligand for heparan sulfate on exosomes has not been identified. Using exosomes isolated from myeloma cell lines and from myeloma patients, we identify exosomal fibronectin as a key heparan sulfate-binding ligand and mediator of exosome-cell interactions. We discovered that heparan sulfate plays a dual role in exosome-cell interaction; heparan sulfate on exosomes captures fibronectin, and on target cells it acts as a receptor for fibronectin. Removal of heparan sulfate from the exosome surface releases fibronectin and dramatically inhibits exosome-target cell interaction. Antibody specific for the Hep-II heparin-binding domain of fibronectin blocks exosome interaction with tumor cells or with marrow stromal cells. Regarding exosome function, fibronectin-mediated binding of exosomes to myeloma cells activated p38 and pERK signaling and expression of downstream target genes DKK1 and MMP-9, two molecules that promote myeloma progression. Antibody against fibronectin inhibited the ability of myeloma-derived exosomes to stimulate endothelial cell invasion. Heparin or heparin mimetics including Roneparstat, a modified heparin in phase I trials in myeloma patients, significantly inhibited exosome-cell interactions. These studies provide the first evidence that fibronectin binding to heparan sulfate mediates exosome-cell interactions, revealing a fundamental mechanism important for exosome-mediated cross-talk within tumor microenvironments. Moreover, these results imply that therapeutic disruption of fibronectin-heparan sulfate interactions will negatively impact myeloma tumor growth and progression.

  17. The signaling symphony: T cell receptor tunes cytokine-mediated T cell differentiation.

    PubMed

    Huang, Weishan; August, Avery

    2015-03-01

    T cell development, differentiation, and maintenance are orchestrated by 2 key signaling axes: the antigen-specific TCR and cytokine-mediated signals. The TCR signals the recognition of self- and foreign antigens to control T cell homeostasis for immune tolerance and immunity, which is regulated by a variety of cytokines to determine T cell subset homeostasis and differentiation. TCR signaling can synergize with or antagonize cytokine-mediated signaling to fine tune T cell fate; however, the latter is less investigated. Murine models with attenuated TCR signaling strength have revealed that TCR signaling can function as regulatory feedback machinery for T cell homeostasis and differentiation in differential cytokine milieus, such as IL-2-mediated Treg development; IL-7-mediated, naïve CD8(+) T cell homeostasis; and IL-4-induced innate memory CD8(+) T cell development. In this review, we discuss the symphonic cross-talk between TCR and cytokine-mediated responses that differentially control T cell behavior, with a focus on the negative tuning by TCR activation on the cytokine effects.

  18. [Delayed hypersensitivity to protamine and immediate hypersensitivity to insulin].

    PubMed

    Köllner, A; Senff, H; Engelmann, L; Kalveram, K J; Velcovsky, H G; Haneke, E

    1991-08-16

    A 63-year-old female, with type II diabetes mellitus, diagnosed in 1967, was started on combination therapy with sulphonylureas and human depot insulin in May 1989, because of inadequate blood sugar control with sulphonylureas alone. Within 3 months she began to develop nodular skin reactions at the site of injection, 12-24 hours after insulin injections. Intradermal testing demonstrated delayed (Gell and Coombs type IV) hypersensitivity to protamine. No specific IgE or IgG antibodies were demonstrable. She was changed to protamine-free human delayed action insulin. After an initial reaction-free period, red urticarial lesions, attributable to immediate (Gell and Coombs type I) hypersensitivity to human insulin, appeared at the injection sites. There were no other complications with continued insulin therapy, and after about 6 weeks no further local reactions were detectable. When an allergic reaction to an insulin preparation is suspected, careful immunological investigation should be performed, to ensure adequate treatment without risk to the patient.

  19. Cell mediated autoimmune granulocytopenia in a case of Felty's syndrome.

    PubMed Central

    Slavin, S; Liang, M H

    1980-01-01

    A variety of mechanisms have been demonstrated or suggested to explain the neutropenia that accompanies Felty's syndrome. This case report presents with Felty's syndrome with recurrent infections with initially had a clinical response to splenectomy. Eleven years later profound neutropenia recurred. In-vitro evidence for cell mediated autosensitisation of peripheral blood lymphocytes to autologous bone marrow cells was found. The cellular abnormalities improved after high-dose corticosteroids but not lithium. However, there did not appear to be a reduction in the incidence of clinical infections. The finding suggests that granulocytopenia in some patients with Felty's syndrome may be an autoimmune phenomenon. PMID:7436567

  20. Cell-Specific Aptamer-Mediated Targeted Drug Delivery

    PubMed Central

    Zhou, Jiehua

    2011-01-01

    Nucleic acid aptamers are in vitro-selected small, single-stranded DNA or RNA oligonucleotides that can specifically recognize their target on the basis of their unique 3-dimensional structures. Recent advances in the development of escort aptamers to deliver and enhance the efficacy of other therapeutic agents have drawn enthusiasm in exploiting cell-type-specific aptamers as drug delivery vehicles. This review mainly focuses on the recent developments of aptamer-mediated targeted delivery systems. We also place particular emphasis on aptamers evolved against cell membrane receptors and possibilities for translation to clinical applications. PMID:21182455

  1. N-Cadherin-Mediated Signaling Regulates Cell Phenotype for Nucleus Pulposus Cells of the Intervertebral Disc

    PubMed Central

    Hwang, Priscilla Y.; Jing, Liufang; Michael, Keith W.; Richardson, William J.; Chen, Jun; Setton, Lori A.

    2015-01-01

    Juvenile nucleus pulposus (NP) cells of the intervertebral disc (IVD) are large, vacuolated cells that form cell clusters with strong cell–cell interactions. With maturation and aging, NP cells lose their ability to form these cell clusters, with aging-associated changes in NP cell phenotype, morphology, and proteoglycan synthesis that may contribute to IVD degeneration. Therefore, it is important to understand the mechanisms governing juvenile NP cell cluster behavior towards the goal of revealing factors that can promote juvenile, healthy NP cell phenotypes. N-cadherin has been identified as a cell–cell adhesion marker that is present in juvenile NP cells, but disappears with age. The goal of this study was to reveal the importance of N-cadherin in regulating cell–cell interactions in juvenile NP cell cluster formation and test for a regulatory role in maintaining a juvenile NP phenotype in vitro. Juvenile porcine IVD cells, of notochordal origin, were promoted to form cell clusters in vitro, and analyzed for preservation of the juvenile NP phenotype. Additionally, cadherin-blocking experiments were performed to prevent cluster formation in order to study the importance of cluster formation in NP cell signaling. Findings reveal N-cadherin-mediated cell–cell contacts promote cell clustering behavior and regulate NP cell matrix production and preservation of NP-specific markers. Inhibition of N-cadherin-mediated contacts resulted in loss of all features of the juvenile NP cell. These results establish a regulatory role for N-cadherin in juvenile NP cells, and suggest that preservation of the N-cadherin mediated cell–cell contact is important for preserving juvenile NP cell phenotype and morphology. PMID:25848407

  2. Mold-induced hypersensitivity pneumonitis.

    PubMed

    Greenberger, Paul A

    2004-01-01

    Mold-induced hypersensitivity pneumonitis results from macrophage- and lymphocyte-driven inflammation, which may be attributable to contaminated humidifiers or heating-ventilation systems or sources in homes, schools, or workplaces. A case may be suspected when there is water intrusion or inadequate drainage. Some fungal causes include species of Alternaria, Aspergillus, Cryptostroma, Penicillium, Pullularia, Rhodotorula, and Trichosporon. The differential diagnosis includes mold-induced asthma, sick building syndrome, mass psychogenic illness (epidemic hysteria), unjustified fears of "toxic" molds, and conditions causing recurrent pneumonitis. PMID:15510579

  3. PTEN mediates Notch-dependent stalk cell arrest in angiogenesis.

    PubMed

    Serra, Helena; Chivite, Iñigo; Angulo-Urarte, Ana; Soler, Adriana; Sutherland, James D; Arruabarrena-Aristorena, Amaia; Ragab, Anan; Lim, Radiance; Malumbres, Marcos; Fruttiger, Marcus; Potente, Michael; Serrano, Manuel; Fabra, Àngels; Viñals, Francesc; Casanovas, Oriol; Pandolfi, Pier Paolo; Bigas, Anna; Carracedo, Arkaitz; Gerhardt, Holger; Graupera, Mariona

    2015-07-31

    Coordinated activity of VEGF and Notch signals guides the endothelial cell (EC) specification into tip and stalk cells during angiogenesis. Notch activation in stalk cells leads to proliferation arrest via an unknown mechanism. By using gain- and loss-of-function gene-targeting approaches, here we show that PTEN is crucial for blocking stalk cell proliferation downstream of Notch, and this is critical for mouse vessel development. Endothelial deletion of PTEN results in vascular hyperplasia due to a failure to mediate Notch-induced proliferation arrest. Conversely, overexpression of PTEN reduces vascular density and abrogates the increase in EC proliferation induced by Notch blockade. PTEN is a lipid/protein phosphatase that also has nuclear phosphatase-independent functions. We show that both the catalytic and non-catalytic APC/C-Fzr1/Cdh1-mediated activities of PTEN are required for stalk cells' proliferative arrest. These findings define a Notch-PTEN signalling axis as an orchestrator of vessel density and implicate the PTEN-APC/C-Fzr1/Cdh1 hub in angiogenesis.

  4. Modulation of Th1/Th2 immune responses by killed Propionibacterium acnes and its soluble polysaccharide fraction in a type I hypersensitivity murine model: induction of different activation status of antigen-presenting cells.

    PubMed

    Squaiella-Baptistão, Carla Cristina; Teixeira, Daniela; Mussalem, Juliana Sekeres; Ishimura, Mayari Eika; Longo-Maugéri, Ieda Maria

    2015-01-01

    Propionibacterium acnes (P. acnes) is a gram-positive anaerobic bacillus present in normal human skin microbiota, which exerts important immunomodulatory effects, when used as heat- or phenol-killed suspensions. We previously demonstrated that heat-killed P. acnes or its soluble polysaccharide (PS), extracted from the bacterium cell wall, suppressed or potentiated the Th2 response to ovalbumin (OVA) in an immediate hypersensitivity model, depending on the treatment protocol. Herein, we investigated the mechanisms responsible for these effects, using the same model and focusing on the activation status of antigen-presenting cells (APCs). We verified that higher numbers of APCs expressing costimulatory molecules and higher expression levels of these molecules are probably related to potentiation of the Th2 response to OVA induced by P. acnes or PS, while higher expression of toll-like receptors (TLRs) seems to be related to Th2 suppression. In vitro cytokines production in cocultures of dendritic cells and T lymphocytes indicated that P. acnes and PS seem to perform their effects by acting directly on APCs. Our data suggest that P. acnes and PS directly act on APCs, modulating the expression of costimulatory molecules and TLRs, and these differently activated APCs drive distinct T helper patterns to OVA in our model. PMID:25973430

  5. Modulation of Th1/Th2 Immune Responses by Killed Propionibacterium acnes and Its Soluble Polysaccharide Fraction in a Type I Hypersensitivity Murine Model: Induction of Different Activation Status of Antigen-Presenting Cells

    PubMed Central

    Mussalem, Juliana Sekeres; Ishimura, Mayari Eika; Longo-Maugéri, Ieda Maria

    2015-01-01

    Propionibacterium acnes (P. acnes) is a gram-positive anaerobic bacillus present in normal human skin microbiota, which exerts important immunomodulatory effects, when used as heat- or phenol-killed suspensions. We previously demonstrated that heat-killed P. acnes or its soluble polysaccharide (PS), extracted from the bacterium cell wall, suppressed or potentiated the Th2 response to ovalbumin (OVA) in an immediate hypersensitivity model, depending on the treatment protocol. Herein, we investigated the mechanisms responsible for these effects, using the same model and focusing on the activation status of antigen-presenting cells (APCs). We verified that higher numbers of APCs expressing costimulatory molecules and higher expression levels of these molecules are probably related to potentiation of the Th2 response to OVA induced by P. acnes or PS, while higher expression of toll-like receptors (TLRs) seems to be related to Th2 suppression. In vitro cytokines production in cocultures of dendritic cells and T lymphocytes indicated that P. acnes and PS seem to perform their effects by acting directly on APCs. Our data suggest that P. acnes and PS directly act on APCs, modulating the expression of costimulatory molecules and TLRs, and these differently activated APCs drive distinct T helper patterns to OVA in our model. PMID:25973430

  6. IL12-mediated sensitizing of T-cell receptor-dependent and -independent tumor cell killing.

    PubMed

    Braun, Matthias; Ress, Marie L; Yoo, Young-Eun; Scholz, Claus J; Eyrich, Matthias; Schlegel, Paul G; Wölfl, Matthias

    2016-07-01

    Interleukin 12 (IL12) is a key inflammatory cytokine critically influencing Th1/Tc1-T-cell responses at the time of initial antigen encounter. Therefore, it may be exploited for cancer immunotherapy. Here, we investigated how IL12, and other inflammatory cytokines, shape effector functions of human T-cells. Using a defined culture system, we followed the gradual differentiation and function of antigen-specific CD8(+) T cells from their initial activation as naïve T cells through their expansion phase as early memory cells to full differentiation as clonally expanded effector T cells. The addition of IL12 8 days after the initial priming event initiated two mechanistically separate events: First, IL12 sensitized the T-cell receptor (TCR) for antigen-specific activation, leading to an approximately 10-fold increase in peptide sensitivity and, in consequence, enhanced tumor cell killing. Secondly, IL12 enabled TCR/HLA-independent activation and cytotoxicity: this "non-specific" effect was mediated by the NK cell receptor DNAM1 (CD226) and dependent on ligand expression of the target cells. This IL12 regulated, DNAM1-mediated killing is dependent on src-kinases as well as on PTPRC (CD45) activity. Thus, besides enhancing TCR-mediated activation, we here identified for the first time a second IL12 mediated mechanism leading to activation of a receptor-dependent killing pathway via DNAM1. PMID:27622043

  7. Suppression of autophagy exacerbates Mefloquine-mediated cell death.

    PubMed

    Shin, Ji Hyun; Park, So Jung; Jo, Yoon Kyung; Kim, Eun Sung; Kang, Hee; Park, Ji-Ho; Lee, Eunjoo H; Cho, Dong-Hyung

    2012-05-01

    Mefloquine is an effective treatment drug for malaria. However, it can cause several adverse side effects, and the precise mechanism associated with the adverse neurological effects of Mefloquine is not clearly understood. In this study, we investigated the effect of Mefloquine on autophagy in neuroblastoma cells. Mefloquine treatment highly induced the formation of autophagosomes and the conversion of LC3I into LC3II. Moreover, Mefloquine-induced autophagy was efficiently suppressed by an autophagy inhibitor and by down regulation of ATG6. The autophagy was also completely blocked in ATG5 deficient mouse embryonic fibroblast cells. Moreover, suppression of autophagy significantly intensified Mefloquine-mediated cytotoxicity in SH-SY5Y cells. Our findings suggest that suppression of autophagy may exacerbate Mefloquine toxicity in neuroblastoma cells.

  8. Sphingosine kinase-1 mediates androgen-induced osteoblast cell growth

    SciTech Connect

    Martin, Claire; Lafosse, Jean-Michel; Malavaud, Bernard; Cuvillier, Olivier

    2010-01-01

    Herein we report that the lipid kinase sphingosine kinase-1 (SphK1) is instrumental in mediating androgen-induced cell proliferation in osteoblasts. Dihydrotestosterone (DHT) triggered cell growth in steroid-deprived MC3T3 cells, which was associated with a rapid stimulation of SphK1 and activation of both Akt and ERK signaling pathways. This mechanism relied on functional androgen receptor/PI3K/Akt nongenotropic signaling as pharmacological antagonists could block SphK1 stimulation by DHT and its consequences. Finally, SphK1 inhibition not only abrogated DHT-induced ERK activation but also blocked cell proliferation, while ERK inhibition had no impact, suggesting that SphK1 was critical for DHT signaling yet independently of the ERK.

  9. Inferring RBP-Mediated Regulation in Lung Squamous Cell Carcinoma

    PubMed Central

    Lafzi, Atefeh; Kazan, Hilal

    2016-01-01

    RNA-binding proteins (RBPs) play key roles in post-transcriptional regulation of mRNAs. Dysregulations in RBP-mediated mechanisms have been found to be associated with many steps of cancer initiation and progression. Despite this, previous studies of gene expression in cancer have ignored the effect of RBPs. To this end, we developed a lasso regression model that predicts gene expression in cancer by incorporating RBP-mediated regulation as well as the effects of other well-studied factors such as copy-number variation, DNA methylation, TFs and miRNAs. As a case study, we applied our model to Lung squamous cell carcinoma (LUSC) data as we found that there are several RBPs differentially expressed in LUSC. Including RBP-mediated regulatory effects in addition to the other features significantly increased the Spearman rank correlation between predicted and measured expression of held-out genes. Using a feature selection procedure that accounts for the adaptive search employed by lasso regularization, we identified the candidate regulators in LUSC. Remarkably, several of these candidate regulators are RBPs. Furthermore, majority of the candidate regulators have been previously found to be associated with lung cancer. To investigate the mechanisms that are controlled by these regulators, we predicted their target gene sets based on our model. We validated the target gene sets by comparing against experimentally verified targets. Our results suggest that the future studies of gene expression in cancer must consider the effect of RBP-mediated regulation. PMID:27186987

  10. Curcumin Attenuates Staurosporine-Mediated Death of Retinal Ganglion Cells

    PubMed Central

    Burugula, Balabharathi; Ganesh, Bhagyalaxmi S.

    2011-01-01

    Purpose. Staurosporine (SS) causes retinal ganglion cell (RGC) death in vivo, but the underlying mechanisms have been unclear. Since previous studies on RGC-5 cells indicated that SS induces cell death by elevating proteases, this study was undertaken to investigate whether SS induces RGC loss by elevating proteases in the retina, and curcumin prevents SS-mediated death of RGCs. Methods. Transformed mouse retinal ganglion-like cells (RGC-5) were treated with 2.0 μM SS and various doses of curcumin. Two optimal doses of SS (12.5 and 100 nM) and curcumin (2.5 and 10 μM) were injected into the vitreous of C57BL/6 mice. Matrix metalloproteinase (MMP)-9, tissue plasminogen activator (tPA), and urokinase plasminogen activator (uPA) activities were assessed by zymography assays. Viability of RGC-5 cells was assessed by MTT assays. RGC and amacrine cell loss in vivo was assessed by immunostaining with Brn3a and ChAT antibodies, respectively. Frozen retinal cross sections were immunostained for nuclear factor-κB (NF-κB). Results. Staurosporine induced uPA and tPA levels in RGC-5 cells, and MMP-9, uPA, and tPA levels in the retinas and promoted the death of RGC-5 cells in vitro and RGCs and amacrine cells in vivo. In contrast, curcumin attenuated RGC and amacrine cell loss, despite elevated levels of proteases. An NF-κB inhibitory peptide reversed curcumin-mediated protective effect on RGC-5 cells, but did not inhibit protease levels. Curcumin did not inhibit protease levels in vivo, but attenuated RGC and amacrine cell loss by restoring NF-κB expression. Conclusions. The results show that curcumin attenuates RGC and amacrine cell death despite elevated levels of proteases and raises the possibility that it may be used as a plausible adjuvant therapeutic agent to prevent the loss of these cells in retinal degenerative conditions. PMID:21498608

  11. Salmonella Modulates B Cell Biology to Evade CD8+ T Cell-Mediated Immune Responses

    PubMed Central

    Lopez-Medina, Marcela; Perez-Lopez, Araceli; Alpuche-Aranda, Celia; Ortiz-Navarrete, Vianney

    2014-01-01

    Although B cells and antibodies are the central effectors of humoral immunity, B cells can also produce and secrete cytokines and present antigen to helper T cells. The uptake of antigen is mainly mediated by endocytosis; thus, antigens are often presented by MHC-II molecules. However, it is unclear if B cells can present these same antigens via MHC-I molecules. Recently, Salmonella bacteria were found to infect B cells, allowing possible antigen cross-processing that could generate bacterial peptides for antigen presentation via MHC-I molecules. Here, we will discuss available knowledge regarding Salmonella antigen presentation by infected B cell MHC-I molecules and subsequent inhibitory effects on CD8+ T cells for bacterial evasion of cell-mediated immunity. PMID:25484884

  12. A role for cell adhesion in beryllium-mediated lung disease

    SciTech Connect

    Hong-geller, Elizabeth

    2008-01-01

    Chronic beryllium disease (CBD) is a debilitating lung disorder in which exposure to the lightweight metal beryllium (Be) causes the accumulation of beryllium-specific CD4+ T cells in the lung and formation of noncaseating pulmonary granulomas. Treatment for CBD patients who exhibit progressive pulmonary decline is limited to systemic corticosteroids, which suppress the severe host inflammatory response. Studies in the past several years have begun to highlight cell-cell adhesion interactions in the development of Be hypersensitivity and CBD. In particular, the high binding affinity between intercellular adhesion molecule 1 (I-CAM1) on lung epithelial cells and the {beta}{sub 2} integrin LFA-1 on migrating lymphocytes and macrophages regulates the concerted rolling of immune cells to sites of inflammation in the lung. In this review, we discuss the evidence that implicates cell adhesion processes in onset of Be disease and the potential of cell adhesion as an intervention point for development of novel therapies.

  13. Paediatric feather duvet hypersensitivity pneumonitis.

    PubMed

    Jordan, Louise E; Guy, Emma

    2015-01-01

    A previously well 12-year-old boy was admitted with a second insidious episode of dyspnoea, dry cough, anorexia, weight loss and chest pain. At admission, he had an oxygen requirement, significantly impaired lung function and reduced exercise tolerance. Initial forced expiratory volume in 1 s was 26%; a 3 min exercise test stopped at 1 min 50 when saturations dropped to 85%. CT scan showed ground-glass nodularity with lymphadenopathy. Bronchoalveolar lavage (BAL) for Pneumocystis carinii pneumonia and viruses were negative, and microbiology results for the BAL were reported in the absence of histology. This is because at the time the BAL samples were collected, a lung biopsy was performed. The biopsy was consistent with hypersensitivity pneumonitis. Echo was normal and CT pulmonary angiography negative. After taking a thorough history, exposure to feather duvets prior to each episode was elicited. IgG of avian precipitants was raised at 10.6 mgA/L (normal <10 mgA/L). Clinical improvement began with avoidance of exposure, while the boy was an inpatient. Antigen avoidance continued on discharge. He continues to improve since discharge. The condition was diagnosed as hypersensitivity pneumonitis secondary to exposure to antigens from feather duvets. PMID:26113584

  14. Paediatric feather duvet hypersensitivity pneumonitis.

    PubMed

    Jordan, Louise E; Guy, Emma

    2015-01-01

    A previously well 12-year-old boy was admitted with a second insidious episode of dyspnoea, dry cough, anorexia, weight loss and chest pain. At admission, he had an oxygen requirement, significantly impaired lung function and reduced exercise tolerance. Initial forced expiratory volume in 1 s was 26%; a 3 min exercise test stopped at 1 min 50 when saturations dropped to 85%. CT scan showed ground-glass nodularity with lymphadenopathy. Bronchoalveolar lavage (BAL) for Pneumocystis carinii pneumonia and viruses were negative, and microbiology results for the BAL were reported in the absence of histology. This is because at the time the BAL samples were collected, a lung biopsy was performed. The biopsy was consistent with hypersensitivity pneumonitis. Echo was normal and CT pulmonary angiography negative. After taking a thorough history, exposure to feather duvets prior to each episode was elicited. IgG of avian precipitants was raised at 10.6 mgA/L (normal <10 mgA/L). Clinical improvement began with avoidance of exposure, while the boy was an inpatient. Antigen avoidance continued on discharge. He continues to improve since discharge. The condition was diagnosed as hypersensitivity pneumonitis secondary to exposure to antigens from feather duvets.

  15. Mannan as an antigen in cell-mediated immunity (CMI) assays and as a modulator of mannan-specific CMI.

    PubMed

    Domer, J E; Garner, R E; Befidi-Mengue, R N

    1989-03-01

    Mannan (MAN) extracted from Candida albicans 20A was investigated for its potential as an antigen in the detection of cell-mediated immunity (CMI) in vivo and in vitro and for its ability to modulate CMI when administered intravenously (i.v.). CBA/J mice were either immunized as adults by the cutaneous inoculation of 10(6) viable blastoconidia or colonized as infants (primed) and then boosted cutaneously as adults. When immunized animals were footpad tested with MAN, highly significant delayed-type hypersensitivity (DH) responses were detected. The DH responses to MAN were of a greater magnitude than those noted with the same quantity of cell wall glycoprotein (GP), an ethylenediamine extract of the cell wall which contains both glucan and MAN. In contrast, GP was a better antigen for the detection of CMI responses in an in vitro lymphoproliferative assay with either spleen or lymph node cell suspensions. Mice treated with MAN i.v. prior to the initiation of immunization or between priming and secondary inoculations developed significantly suppressed DH reactions when tested with either MAN or GP. The lowest effective dose of MAN was 250 micrograms, maximum suppression occurred with 500 micrograms, and either dose given 1 week prior to immunization was suppressive. The suppression by MAN was specific for MAN or the MAN-containing GP. Responses to another unrelated candidal antigen, a membrane extract designated BEX, were relatively unaffected. MAN, therefore, was an effective antigen for the detection of CMI in vivo, and its administration i.v. created what appeared to be a MAN-specific suppression since it could be detected with both MAN and a MAN-containing extract from the cell wall. Caution must be exercised in the interpretation of these data, however, since the protein component of each of these extracts has not been characterized with respect to its potential role in the phenomena observed.

  16. Rac1 mediates intestinal epithelial cell apoptosis via JNK.

    PubMed

    Jin, Shi; Ray, Ramesh M; Johnson, Leonard R

    2006-12-01

    Apoptosis plays a key role in the maintenance of a constant cell number and a low incidence of cancer in the mucosa of the intestine. Although the small GTPase Rac1 has been established as an important regulator of migration of intestinal epithelial cells, whether Rac1 is also involved in apoptosis is unclear. The present study tested the hypothesis that Rac1 mediates TNF-alpha-induced apoptosis in IEC-6 cells. Rac1 is activated during TNF-alpha-induced apoptosis as judged by the level of GTP-Rac1, the level of microsomal membrane-associated Rac1, and lamellipodia formation. Although expression of constitutively active Rac1 does not increase apoptosis in the basal condition, inhibition of Rac1 either by NSC-23766 (Rac1 inhibitor) or expression of dominant negative Rac1 protects cells from TNF-alpha-induced apoptosis by inhibiting caspase-3, -8, and -9 activities. Inhibition of Rac1 before the administration of apoptotic stimuli significantly prevents TNF-alpha-induced activation of JNK1/2, the key proapoptotic regulator in IEC-6 cells. Inhibition of Rac1 does not modulate TNF-alpha-induced ERK1/2 and Akt activation. Inhibition of ERK1/2 and Akt activity by U-0126 and LY-294002, respectively, increased TNF-alpha-induced apoptosis. However, inhibition of Rac1 significantly decreased apoptosis in the presence of ERK1/2 and Akt inhibitors, similar to the effect observed with NSC-23766 alone in response to TNF-alpha. Thus, Rac1 inhibition protects cells independently of ERK1/2 and Akt activation during TNF-alpha-induced apoptosis. Although p38 MAPK is activated in response to TNF-alpha, inhibition of p38 MAPK did not decrease apoptosis. Rac1 inhibition did not alter p38 MAPK activity. Thus, these results indicate that Rac1 mediates apoptosis via JNK and plays a key role in proapoptotic pathways in intestinal epithelial cells.

  17. Hypersensitivity reactions to titanium: diagnosis and management.

    PubMed

    Wood, Megan M; Warshaw, Erin M

    2015-01-01

    Titanium is notable for its biocompatibility and is used as biologic implant material across surgical specialties, especially in metal-sensitive individuals. However, rare cases of titanium hypersensitivity reactions are reported in the literature. This article discusses the properties and biological behavior of titanium and provides a thorough review of the literature on reported cases, diagnostic techniques, and approach to management of titanium hypersensitivity.

  18. Management of dentinal hypersensitivity: a review.

    PubMed

    Parolia, Abhishek; Kundabala, M; Mohan, Mandakini

    2011-03-01

    Dentinal hypersensitivity is a very common clinical finding that can cause considerable concern for the patient. Clinicians must understand the various etiological factors, their complexities, and numerous treatment options available. This article reviews the etiology, management, and prevention of dentinal hypersensitivity. PMID:21563596

  19. Effect of early vitamin A supplementation on cell-mediated immunity in infants younger than 6 mo.

    PubMed

    Rahman, M M; Mahalanabis, D; Alvarez, J O; Wahed, M A; Islam, M A; Habte, D

    1997-01-01

    One hundred twenty infants were randomly assigned to receive either 15 mg vitamin A or placebo with each of three DPT/OPV (diphtheria, pertussis, tetanus/oral polio vaccine) immunizations at monthly intervals. Sixty-two received vitamin A and 58 received placebo. One month after the third supplementation dose, the response to the delayed cutaneous hypersensitivity test [multitest cell-mediated immunity (CMI) skin evaluation] for tetanus, diphtheria, and tuberculin (purified protein derivative, PPD) was the same in the vitamin A and placebo infants. The number of anergic infants was 17 (27%) and 19 (33%) in the vitamin A and placebo groups, respectively. The number of positive tests among well-nourished infants was significantly higher than that in malnourished infants irrespective of supplementation (P < 0.001). Among the infants with adequate serum retinol concentrations (> 0.7 mumol/L) after supplementation, the vitamin A-supplemented infants had a significantly higher proportion of positive CMI tests than the placebo infants (chi-square test: 8.99, P = 0.008). Among the infants with low serum retinol concentrations (< 0.7 mumol/L) after supplementation, vitamin A supplementation had no effect on CMI response. These results indicate that CMI in young infants was positively affected by vitamin A supplementation only in those infants whose vitamin A status was adequate (ie, serum retinol > 0.7 mumol/L) at the time of the CMI test. CMI was consistently better in well-nourished infants irrespective of supplementation. PMID:8988926

  20. Cord blood T cells mediate enhanced antitumor effects compared with adult peripheral blood T cells.

    PubMed

    Hiwarkar, Prashant; Qasim, Waseem; Ricciardelli, Ida; Gilmour, Kimberly; Quezada, Sergio; Saudemont, Aurore; Amrolia, Persis; Veys, Paul

    2015-12-24

    Unrelated cord blood transplantation (CBT) without in vivo T-cell depletion is increasingly used to treat high-risk hematologic malignancies. Following T-replete CBT, naïve CB T cells undergo rapid peripheral expansion with memory-effector differentiation. Emerging data suggest that unrelated CBT, particularly in the context of HLA mismatch and a T-replete graft, may reduce leukemic relapse. To study the role of CB T cells in mediating graft-versus-tumor responses and dissect the underlying immune mechanisms for this, we compared the ability of HLA-mismatched CB and adult peripheral blood (PB) T cells to eliminate Epstein-Barr virus (EBV)-driven human B-cell lymphoma in a xenogeneic NOD/SCID/IL2rg(null) mouse model. CB T cells mediated enhanced tumor rejection compared with equal numbers of PB T cells, leading to improved survival in the CB group (P < .0003). Comparison of CB T cells that were autologous vs allogeneic to the lymphoma demonstrated that this antitumor effect was mediated by alloreactive rather than EBV-specific T cells. Analysis of tumor-infiltrating lymphocytes demonstrated that CB T cells mediated this enhanced antitumor effect by rapid infiltration of the tumor with CCR7(+)CD8(+) T cells and prompt induction of cytotoxic CD8(+) and CD4(+) T-helper (Th1) T cells in the tumor microenvironment. In contrast, in the PB group, this antilymphoma effect is impaired because of delayed tumoral infiltration of PB T cells and a relative bias toward suppressive Th2 and T-regulatory cells. Our data suggest that, despite being naturally programmed toward tolerance, reconstituting T cells after unrelated T-replete CBT may provide superior Tc1-Th1 antitumor effects against high-risk hematologic malignancies.

  1. Hypersensitivity reactions to synthetic haemodialysis membranes.

    PubMed

    Sánchez-Villanueva, Rafael J; González, Elena; Quirce, Santiago; Díaz, Raquel; Alvarez, Laura; Menéndez, David; Rodríguez-Gayo, Lucía; Bajo, M Auxiliadora; Selgas, Rafael

    2014-01-01

    Undergoing a haemodialysis (HD) session poses a certain risk of hypersensitivity adverse reactions as large quantities of blood are in contact with various synthetic materials. Hypersensitivity reactions to ethylene oxide and non-biocompatible membranes, such as cuprophane, have been described in HD. Cases of hypersensitivity with biocompatible membranes, such as polysulfone, and even polysulfone-polyvinylpyrrolidone, have also been reported. In this article we describe six cases of mostly early-stage hypersensitivity reactions to HD occurring in our department, characterised by malaise, desaturation, bronchospasm and arterial hypotension, with good response to the session’s temporary suspension and with reappearance in subsequent sessions that used a synthetic dialyser. No hypersensitivity reactions reappeared in successive observations when the sessions were carried out using a cellulose membrane.

  2. Protein Kinase G facilitates EGFR-mediated cell death in MDA-MB-468 cells.

    PubMed

    Jackson, Nicole M; Ceresa, Brian P

    2016-08-15

    The Epidermal Growth Factor Receptor (EGFR) is a transmembrane receptor tyrosine kinase with critical implications in cell proliferation, migration, wound healing and the regulation of apoptosis. However, the EGFR has been shown to be hyper-expressed in a number of human malignancies. The MDA-MB-468 metastatic breast cell line is one example of this. This particular cell line hyper-expresses the EGFR and undergoes EGFR-mediated apoptosis in response to EGF ligand. The goal of this study was to identify the kinases that could be potential intermediates for the EGFR-mediated induction of apoptosis intracellularly. After identifying Cyclic GMP-dependent Protein Kinase G (PKG) as a plausible intermediate, we wanted to determine the temporal relationship of these two proteins in the induction of apoptosis. We observed a dose-dependent decrease in MDA-MB-468 cell viability, which was co-incident with increased PKG activity as measured by VASPSer239 phosphorylation. In addition, we observed a dose dependent decrease in cell viability, as well as an increase in apoptosis, in response to two different PKG agonists, 8-Bromo-cGMP and 8-pCPT-cGMP. MDA-MB-468 cells with reduced PKG activity had attenuated EGFR-mediated apoptosis. These findings indicate that PKG does not induce cell death via transphosphorylation of the EGFR. Instead, PKG activity occurs following EGFR activation. Together, these data indicate PKG as an intermediary in EGFR-mediated cell death, likely via apoptotic pathway. PMID:27381222

  3. In healthy primates, circulating autoreactive T cells mediate autoimmune disease.

    PubMed Central

    Genain, C P; Lee-Parritz, D; Nguyen, M H; Massacesi, L; Joshi, N; Ferrante, R; Hoffman, K; Moseley, M; Letvin, N L; Hauser, S L

    1994-01-01

    A T cell response against myelin basic protein (MBP) is thought to contribute to the central nervous system (CNS) inflammation that occurs in the human demyelinating disease multiple sclerosis. To test whether MBP-reactive T cells that are normally retrieved from the circulation are capable of inducing CNS disease, MBP-reactive T cell clones were isolated from the peripheral blood of healthy, unimmunized Callithrix jacchus (C. jacchus) marmosets. This primate species is characterized by a natural chimerism of bone marrow elements between siblings that should make possible adoptive transfer of MBP-reactive T cells. We report that MBP-reactive T cell clones efficiently and reproducibly transfer CNS inflammatory disease between members of C. jacchus chimeric sets. The demyelination that is characteristic of experimental allergic encephalomyelitis induced in C. jacchus by immunization against human white matter did not occur after adoptive transfer of the MBP-reactive clones. It was noteworthy that encephalitogenic T cell clones were diverse in terms of their recognition of different epitopes of MBP, distinguishing the response in C. jacchus from that in some inbred rodents in which restricted recognition of MBP occurs. These findings are the first direct evidence that natural populations of circulating T cells directed against a CNS antigen can mediate an inflammatory autoimmune disease. Images PMID:7521889

  4. Siglecs as targets for therapy in immune cell mediated disease

    PubMed Central

    O’Reilly, Mary K.; Paulson, James C.

    2010-01-01

    The sialic acid-binding immunoglobulin-like lectins (siglecs) comprise a family of receptors that are differentially expressed on leukocytes and other immune cells. The restricted expression of several siglecs to one or a few cell types makes them attractive targets for cell-directed therapies. The anti-CD33 (Siglec-3) antibody Gemtuzumab (Mylotarg™) is approved for treatment of acute myeloid leukemia (AML), and antibodies targeting CD22 (Siglec-2) are currently in clinical trials for treatment of B cell non-Hodgkins lymphomas and autoimmune diseases. Because siglecs are endocytic receptors, they are well suited for a ‘Trojan horse’ strategy, whereby therapeutic agents conjugated to an antibody, or multimeric glycan ligand, bind to the siglec and are efficiently carried into the cell. Although the rapid internalization of unmodified siglec antibodies reduces their utility for induction of antibody-dependent cellular cytotoxicity (ADCC) or complement-mediated cytotoxicity (CDC), antibody binding of Siglec-8, Siglec-9, and CD22 have been demonstrated to induce apoptosis of eosinophils, neutrophils, and depletion of B cells, respectively. Here we review the properties of siglecs that make them attractive for cell-targeted therapies. PMID:19359050

  5. Pain hypersensitivity and spinal nociceptive hypersensitivity in chronic pain: prevalence and associated factors.

    PubMed

    Curatolo, Michele; Müller, Monika; Ashraf, Aroosiah; Neziri, Alban Y; Streitberger, Konrad; Andersen, Ole K; Arendt-Nielsen, Lars

    2015-11-01

    Hypersensitivity of pain pathways is considered a relevant determinant of symptoms in chronic pain patients, but data on its prevalence are very limited. To our knowledge, no data on the prevalence of spinal nociceptive hypersensitivity are available. We studied the prevalence of pain hypersensitivity and spinal nociceptive hypersensitivity in 961 consecutive patients with various chronic pain conditions. Pain threshold and nociceptive withdrawal reflex threshold to electrical stimulation were used to assess pain hypersensitivity and spinal nociceptive hypersensitivity, respectively. Using 10th percentile cutoff of previously determined reference values, the prevalence of pain hypersensitivity and spinal nociceptive hypersensitivity (95% confidence interval) was 71.2 (68.3-74.0) and 80.0 (77.0-82.6), respectively. As a secondary aim, we analyzed demographic, psychosocial, and clinical characteristics as factors potentially associated with pain hypersensitivity and spinal nociceptive hypersensitivity using logistic regression models. Both hypersensitivity parameters were unaffected by most factors analyzed. Depression, catastrophizing, pain-related sleep interference, and average pain intensity were significantly associated with hypersensitivity. However, none of them was significant for both unadjusted and adjusted analyses. Furthermore, the odds ratios were very low, indicating modest quantitative impact. To our knowledge, this is the largest prevalence study on central hypersensitivity and the first one on the prevalence of spinal nociceptive hypersensitivity in chronic pain patients. The results revealed an impressively high prevalence, supporting a high clinical relevance of this phenomenon. Electrical pain thresholds and nociceptive withdrawal reflex explore aspects of pain processing that are mostly independent of sociodemographic, psychological, and clinical pain-related characteristics.

  6. RB mutation and RAS overexpression induce resistance to NK cell-mediated cytotoxicity in glioma cells.

    PubMed

    Orozco-Morales, Mario; Sánchez-García, Francisco Javier; Golán-Cancela, Irene; Hernández-Pedro, Norma; Costoya, Jose A; de la Cruz, Verónica Pérez; Moreno-Jiménez, Sergio; Sotelo, Julio; Pineda, Benjamín

    2015-01-01

    Several theories aim to explain the malignant transformation of cells, including the mutation of tumor suppressors and proto-oncogenes. Deletion of Rb (a tumor suppressor), overexpression of mutated Ras (a proto-oncogene), or both, are sufficient for in vitro gliomagenesis, and these genetic traits are associated with their proliferative capacity. An emerging hallmark of cancer is the ability of tumor cells to evade the immune system. Whether specific mutations are related with this, remains to be analyzed. To address this issue, three transformed glioma cell lines were obtained (Rb(-/-), Ras(V12), and Rb(-/-)/Ras(V12)) by in vitro retroviral transformation of astrocytes, as previously reported. In addition, Ras(V12) and Rb(-/-)/Ras(V12) transformed cells were injected into SCID mice and after tumor growth two stable glioma cell lines were derived. All these cells were characterized in terms of Rb and Ras gene expression, morphology, proliferative capacity, expression of MHC I, Rae1δ, and Rae1αβγδε, mult1, H60a, H60b, H60c, as ligands for NK cell receptors, and their susceptibility to NK cell-mediated cytotoxicity. Our results show that transformation of astrocytes (Rb loss, Ras overexpression, or both) induced phenotypical and functional changes associated with resistance to NK cell-mediated cytotoxicity. Moreover, the transfer of cell lines of transformed astrocytes into SCID mice increased resistance to NK cell-mediated cytotoxicity, thus suggesting that specific changes in a tumor suppressor (Rb) and a proto-oncogene (Ras) are enough to confer resistance to NK cell-mediated cytotoxicity in glioma cells and therefore provide some insight into the ability of tumor cells to evade immune responses.

  7. In-cell infection: a novel pathway for Epstein-Barr virus infection mediated by cell-in-cell structures

    PubMed Central

    Ni, Chao; Chen, Yuhui; Zeng, Musheng; Pei, Rongjuan; Du, Yong; Tang, Linquan; Wang, Mengyi; Hu, Yazhuo; Zhu, Hanyu; He, Meifang; Wei, Xiawei; Wang, Shan; Ning, Xiangkai; Wang, Manna; Wang, Jufang; Ma, Li; Chen, Xinwen; Sun, Qiang; Tang, Hong; Wang, Ying; Wang, Xiaoning

    2015-01-01

    Epstein-Barr virus (EBV) can infect both susceptible B lymphocytes and non-susceptible epithelial cells (ECs). Viral tropism analyses have revealed two intriguing means of EBV infection, either by a receptor-mediated infection of B cells or by a cell-to-cell contact-mediated infection of non-susceptible ECs. Herein, we report a novel “in-cell infection” mechanism for EBV infection of non-susceptible ECs through the formation of cell-in-cell structures. Epithelial CNE-2 cells were invaded by EBV-infected Akata B cells to form cell-in-cell structures in vitro. Such unique cellular structures could be readily observed in the specimens of nasopharyngeal carcinoma. Importantly, the formation of cell-in-cell structures led to the autonomous activation of EBV within Akata cells and subsequent viral transmission to CNE-2 cells, as evidenced by the expression of viral genes and the presence of virion particles in CNE-2 cells. Significantly, EBV generated from in-cell infected ECs displayed altered tropism with higher infection efficacy to both B cells and ECs. In addition to CNE-2 tumor cells, cell-in-cell structure formation could also mediate EBV infection of NPEC1-Bmi1 cells, an immortalized nasopharyngeal epithelial cell line. Furthermore, efficient infection by this mechanism involved the activation of the PI3K/AKT signaling pathway. Thus, our study identified “in-cell infection” as a novel mechanism for EBV infection. Given the diversity of virus-infected cells and the prevalence of cell-in-cell structures during chronic infection, we speculate that “in-cell infection” is likely a general mechanism for EBV and other viruses to infect non-susceptible ECs. PMID:25916549

  8. Role of complement and NK cells in antibody mediated rejection.

    PubMed

    Akiyoshi, Takurin; Hirohashi, Tsutomu; Alessandrini, Alessandro; Chase, Catherine M; Farkash, Evan A; Neal Smith, R; Madsen, Joren C; Russell, Paul S; Colvin, Robert B

    2012-12-01

    Despite extensive research on T cells and potent immunosuppressive regimens that target cellular mediated rejection, few regimens have been proved to be effective on antibody-mediated rejection (AMR), particularly in the chronic setting. C4d deposition in the graft has been proved to be a useful marker for AMR; however, there is an imperfect association between C4d and AMR. While complement has been considered as the main player in acute AMR, the effector mechanisms in chronic AMR are still debated. Recent studies support the role of NK cells and direct effects of antibody on endothelium cells in a mechanism suggesting the presence of a complement-independent pathway. Here, we review the history, currently available systems and progress in experimental animal research. Although there are consistent findings from human and animal research, transposing the experimental results from rodent to human has been hampered by the differences in endothelial functions between species. We briefly describe the findings from patients and compare them with results from animals, to propose a combined perspective.

  9. Cell-Mediated Immune Responses in Paraneoplastic Neurological Syndromes

    PubMed Central

    Zaborowski, Mikolaj Piotr

    2013-01-01

    Paraneoplastic neurological syndromes (PNS) are disorders of the nervous system that are associated with remote effects of malignancy. PNS are considered to have an autoimmune pathology. It has been suggested that immune antitumor responses are the origin of improved outcome in PNS. We describe cell-mediated immune responses in PNS and their potential contributions to antitumor reactions. Experimental and neuropathological studies have revealed infiltrates in nervous tissue and disturbances in lymphocyte populations in both cerebrospinal fluid and peripheral blood. A predominance of cytotoxic T lymphocytes (CTLs) over T helper cells has been observed. CTLs can be specifically aggressive against antigens shared by tumors and nervous tissue. Based on genetic studies, a common clonal origin of lymphocytes from blood, tumor, and nervous tissue is suggested. Suppressive regulatory T (Treg) lymphocytes are dysfunctional. Simultaneously, in tumor tissue, more intense cell-mediated immune responses are observed, which often coincide with a less aggressive course of neoplastic disease. An increased titer of onconeural antibodies is also related to better prognoses in patients without PNS. The evaluation of onconeural and neuronal surface antibodies was recommended in current guidelines. The link between PNS emergence and antitumor responses may result from more active CTLs and less functional Treg lymphocytes. PMID:24575143

  10. Sauna lung: hypersensitivity pneumonitis due to Exophiala jeanselmei.

    PubMed

    Huang, Wei-Chen; Lu, Yin-Hsiu; Lin, Zih-Gong; Su, Wen-Lin

    2010-04-01

    A 55-year-old man developed progressive cough and dyspnoea after regular attendance at a public steam bath. Hypoxaemia, diffuse pulmonary infiltrates and a predominance of lymphocytes with an increased percentage of CD8+ T cells in his bronchoalveolar lavage fluid suggested hypersensitivity pneumonitis. Microbial cultures from the steam bath room and tank identified Exophiala jeanselmei. Immunoblotting assays from the patient's serum confirmed the major antigenic stimulus. The patient recovered fully after systemic corticosteroid treatment and cessation of further exposure.

  11. Establishment of Stable, Cell-Mediated Immunity that Makes "Susceptible" Mice Resistant to Leishmania major

    NASA Astrophysics Data System (ADS)

    Bretscher, Peter A.; Wei, Guojian; Menon, Juthika N.; Bielefeldt-Ohmann, Helle

    1992-07-01

    Cell-mediated, but not antibody-mediated, immune responses protect humans against certain pathogens that produce chronic diseases such as leishmaniasis. Effective vaccination against such pathogens must therefore produce an immunological "imprint" so that stable, cell-mediated immunity is induced in all individuals after natural infection. BALB/c mice "innately susceptible" to Leishmania major produce antibodies after substantial infection. In the present study, "susceptible" mice injected with a small number of parasites mounted a cell-mediated response and acquired resistance to a larger, normally pathogenic, challenge. This vaccination strategy may be applicable in diseases in which protection is dependent on cell-mediated immunity.

  12. Phosphoinositide-mediated oligomerization of a defensin induces cell lysis

    PubMed Central

    Poon, Ivan KH; Baxter, Amy A; Lay, Fung T; Mills, Grant D; Adda, Christopher G; Payne, Jennifer AE; Phan, Thanh Kha; Ryan, Gemma F; White, Julie A; Veneer, Prem K; van der Weerden, Nicole L; Anderson, Marilyn A; Kvansakul, Marc; Hulett, Mark D

    2014-01-01

    Cationic antimicrobial peptides (CAPs) such as defensins are ubiquitously found innate immune molecules that often exhibit broad activity against microbial pathogens and mammalian tumor cells. Many CAPs act at the plasma membrane of cells leading to membrane destabilization and permeabilization. In this study, we describe a novel cell lysis mechanism for fungal and tumor cells by the plant defensin NaD1 that acts via direct binding to the plasma membrane phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2). We determined the crystal structure of a NaD1:PIP2 complex, revealing a striking oligomeric arrangement comprising seven dimers of NaD1 that cooperatively bind the anionic headgroups of 14 PIP2 molecules through a unique ‘cationic grip’ configuration. Site-directed mutagenesis of NaD1 confirms that PIP2-mediated oligomerization is important for fungal and tumor cell permeabilization. These observations identify an innate recognition system by NaD1 for direct binding of PIP2 that permeabilizes cells via a novel membrane disrupting mechanism. DOI: http://dx.doi.org/10.7554/eLife.01808.001 PMID:24692446

  13. Lung Regeneration: Endogenous and Exogenous Stem Cell Mediated Therapeutic Approaches.

    PubMed

    Akram, Khondoker M; Patel, Neil; Spiteri, Monica A; Forsyth, Nicholas R

    2016-01-19

    The tissue turnover of unperturbed adult lung is remarkably slow. However, after injury or insult, a specialised group of facultative lung progenitors become activated to replenish damaged tissue through a reparative process called regeneration. Disruption in this process results in healing by fibrosis causing aberrant lung remodelling and organ dysfunction. Post-insult failure of regeneration leads to various incurable lung diseases including chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis. Therefore, identification of true endogenous lung progenitors/stem cells, and their regenerative pathway are crucial for next-generation therapeutic development. Recent studies provide exciting and novel insights into postnatal lung development and post-injury lung regeneration by native lung progenitors. Furthermore, exogenous application of bone marrow stem cells, embryonic stem cells and inducible pluripotent stem cells (iPSC) show evidences of their regenerative capacity in the repair of injured and diseased lungs. With the advent of modern tissue engineering techniques, whole lung regeneration in the lab using de-cellularised tissue scaffold and stem cells is now becoming reality. In this review, we will highlight the advancement of our understanding in lung regeneration and development of stem cell mediated therapeutic strategies in combating incurable lung diseases.

  14. Signals mediating Klotho-induced neuroprotection in hippocampal neuronal cells.

    PubMed

    Cheng, Meng-Fu; Chen, Li-Jen; Niu, Ho-Shan; Yang, Ting-Ting; Lin, Kao-Chang; Cheng, Juei-Tang

    2015-01-01

    The erythropoietin (Epo) receptor (EpoR) is expressed in the brain and was shown to have neuroprotective effects against brain damage in animal models. A recent study indicated that EpoR and its activity are the downstream effectors of Klotho for cytoprotection in the kidney. Thus, we propose that Klotho can stimulate the expression of EpoR in neuronal cells to enhance Epo-mediated protection. H19-7 hippocampal neuronal cells were treated with recombinant Klotho. In H19-7 cells, Klotho increased the expression of both the EpoR protein and mRNA. Klotho also enhanced the transcription activity of the EpoR promoter in H19-7 cells. Moreover, Klotho augmented the Epo-triggered phosphorylation of Jak2 and Stat5 and protected H19-7 cells from hydrogen peroxide cytotoxicity. The silencing of EpoR abolished the protective effect of Klotho against peroxide-induced cytotoxicity. Finally, the silencing of GATA1 diminished the Klotho-induced increase in EpoR protein and mRNA expression as well as its promoter activity. In conclusion, Klotho increased EpoR expression in neuronal cells through GATA1, thereby enabling EpoR to function as a cytoprotective protein against oxidative injury. PMID:25856523

  15. ERK2 mediates metabolic stress response to regulate cell fate

    PubMed Central

    Shin, Sejeong; Buel, Gwen R.; Wolgamott, Laura; Plas, David R.; Asara, John M.; Blenis, John; Yoon, Sang-Oh

    2015-01-01

    Insufficient nutrients disrupt physiological homeostasis resulting in diseases and even death. Considering the physiological and pathological consequences of this metabolic stress, the adaptive responses that cells utilize under this condition are of great interest. We show that under low glucose conditions, cells initiate adaptation followed by apoptosis responses using PERK/Akt and MEK1/ERK2 signaling, respectively. For adaptation, cells engage the endoplasmic reticulum stress-induced unfolded protein response, which results in PERK/Akt activation and cell survival. Sustained and extreme energetic stress promotes a switch to isoform-specific MEK1/ERK2 signaling, induction of GCN2/eIF2α phosphorylation and ATF4 expression, which overrides PERK/Akt-mediated adaptation and induces apoptosis through ATF4-dependent expression of pro-apoptotic factors including Bid and Trb3. ERK2 activation during metabolic stress contributes to changes in TCA cycle and amino acid metabolism, and cell death, which is suppressed by glutamate and α-ketoglutarate supplementation. Taken together, our results reveal promising targets to protect cells or tissues from metabolic stress. PMID:26190261

  16. Lung Regeneration: Endogenous and Exogenous Stem Cell Mediated Therapeutic Approaches.

    PubMed

    Akram, Khondoker M; Patel, Neil; Spiteri, Monica A; Forsyth, Nicholas R

    2016-01-01

    The tissue turnover of unperturbed adult lung is remarkably slow. However, after injury or insult, a specialised group of facultative lung progenitors become activated to replenish damaged tissue through a reparative process called regeneration. Disruption in this process results in healing by fibrosis causing aberrant lung remodelling and organ dysfunction. Post-insult failure of regeneration leads to various incurable lung diseases including chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis. Therefore, identification of true endogenous lung progenitors/stem cells, and their regenerative pathway are crucial for next-generation therapeutic development. Recent studies provide exciting and novel insights into postnatal lung development and post-injury lung regeneration by native lung progenitors. Furthermore, exogenous application of bone marrow stem cells, embryonic stem cells and inducible pluripotent stem cells (iPSC) show evidences of their regenerative capacity in the repair of injured and diseased lungs. With the advent of modern tissue engineering techniques, whole lung regeneration in the lab using de-cellularised tissue scaffold and stem cells is now becoming reality. In this review, we will highlight the advancement of our understanding in lung regeneration and development of stem cell mediated therapeutic strategies in combating incurable lung diseases. PMID:26797607

  17. Mechanosensitive pannexin-1 channels mediate microvascular metastatic cell survival.

    PubMed

    Furlow, Paul W; Zhang, Steven; Soong, T David; Halberg, Nils; Goodarzi, Hani; Mangrum, Creed; Wu, Y Gloria; Elemento, Olivier; Tavazoie, Sohail F

    2015-07-01

    During metastatic progression, circulating cancer cells become lodged within the microvasculature of end organs, where most die from mechanical deformation. Although this phenomenon was first described over a half-century ago, the mechanisms enabling certain cells to survive this metastasis-suppressive barrier remain unknown. By applying whole-transcriptome RNA-sequencing technology to isogenic cancer cells of differing metastatic capacities, we identified a mutation encoding a truncated form of the pannexin-1 (PANX1) channel, PANX1(1-89), as recurrently enriched in highly metastatic breast cancer cells. PANX1(1-89) functions to permit metastatic cell survival during traumatic deformation in the microvasculature by augmenting ATP release from mechanosensitive PANX1 channels activated by membrane stretch. PANX1-mediated ATP release acts as an autocrine suppressor of deformation-induced apoptosis through P2Y-purinergic receptors. Finally, small-molecule therapeutic inhibition of PANX1 channels is found to reduce the efficiency of breast cancer metastasis. These data suggest a molecular basis for metastatic cell survival on microvasculature-induced biomechanical trauma. PMID:26098574

  18. Lung Regeneration: Endogenous and Exogenous Stem Cell Mediated Therapeutic Approaches

    PubMed Central

    Akram, Khondoker M.; Patel, Neil; Spiteri, Monica A.; Forsyth, Nicholas R.

    2016-01-01

    The tissue turnover of unperturbed adult lung is remarkably slow. However, after injury or insult, a specialised group of facultative lung progenitors become activated to replenish damaged tissue through a reparative process called regeneration. Disruption in this process results in healing by fibrosis causing aberrant lung remodelling and organ dysfunction. Post-insult failure of regeneration leads to various incurable lung diseases including chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis. Therefore, identification of true endogenous lung progenitors/stem cells, and their regenerative pathway are crucial for next-generation therapeutic development. Recent studies provide exciting and novel insights into postnatal lung development and post-injury lung regeneration by native lung progenitors. Furthermore, exogenous application of bone marrow stem cells, embryonic stem cells and inducible pluripotent stem cells (iPSC) show evidences of their regenerative capacity in the repair of injured and diseased lungs. With the advent of modern tissue engineering techniques, whole lung regeneration in the lab using de-cellularised tissue scaffold and stem cells is now becoming reality. In this review, we will highlight the advancement of our understanding in lung regeneration and development of stem cell mediated therapeutic strategies in combating incurable lung diseases. PMID:26797607

  19. Adenoviral-vector-mediated gene transfer to dendritic cells.

    PubMed

    Song, W; Crystal, R G

    2001-01-01

    Dendritic cells (DC) are the most potent antigen presenting cells capable of initiating T-cell-dependent immune responses (1-5). This biologic potential can be harnessed to elicit effective antigen-specific immune responses by transferring the relevant antigens to the DC. Once the DC have been mobilized and purified, the relevant antigens can be transferred to the DC as intact proteins, or as peptides representing specific epitopes, or with gene transfer using sequences of DNA or RNA coding for the pertinent antigen(s) (6-15). Theoretically, genetically modifying DC with genes coding for specific antigens has potential advantages over pulsing the DC with peptides repeating the antigen or antigen fragment. First, the genetically modified DC may present previously unknown epitopes in association with different MHC molecules. Second, gene transfer to DC ensures that the gene product is endogenously processed, leading to the generation of MHC class I-restricted cytotoxic T lymphocytes (CTL), the effector arm of cell-mediated immune responses. Finally, in addition to genes coding for the antigen(s), genetic modification of the DC can induce genes coding for mediators relevant to generation of the immune response to the antigen(s), further boosting host responses to the antigens presented by the modified DC. Different gene transfer approaches have been explored to genetically modify DC, including retroviral vectors (16-18), recombinant vaccinia virus vectors (19), and recombinant adenovirus (Ad) vectors (19-23). The focus of this chapter is on using recombinant Ad vectors to transfer genes to murine DC. We have used a similar strategy to transfer genes to human DC (24). As an example of the power of this technology, we will describe the use of Ad-vector-modified DC to suppress the growth of tumor cells modified to express a specific antigen.

  20. New flow cytometric assays for monitoring cell-mediated cytotoxicity.

    PubMed

    Zaritskaya, Liubov; Shurin, Michael R; Sayers, Thomas J; Malyguine, Anatoli M

    2010-06-01

    The exact immunologic responses after vaccination that result in effective antitumor immunity have not yet been fully elucidated and the data from ex vivo T-cell assays have not yet defined adequate surrogate markers for clinical efficacy. A more detailed knowledge of the specific immune responses that correlate with positive clinical outcomes should help to develop better or novel strategies to effectively activate the immune system against tumors. Furthermore, clinically relevant material is often limited and, thus, precludes the ability to perform multiple assays. The two main assays currently used to monitor lymphocyte-mediated cytoxicity in cancer patients are the (51)Cr-release assay and IFN-gamma ELISpot assay. The former has a number of disadvantages, including low sensitivity, poor labeling and high spontaneous release of isotope from some tumor target cells. Additional problems with the (51)Cr-release assay include difficulty in obtaining autologous tumor targets, and biohazard and disposal problems for the isotope. The ELISpot assays do not directly measure cytotoxic activity and are, therefore, a surrogate marker of cyotoxic capacity of effector T cells. Furthermore, they do not assess cytotoxicity mediated by the production of the TNF family of death ligands by the cytotoxic cells. Therefore, assays that allow for the simultaneous measurement of several parameters may be more advantageous for clinical monitoring. In this respect, multifactor flow cytometry-based assays are a valid addition to the currently available immunologic monitoring assays. Use of these assays will enable detection and enumeration of tumor-specific cytotoxic T lymphocytes and their specific effector functions and any correlations with clinical responses. Comprehensive, multifactor analysis of effector cell responses after vaccination may help to detect factors that determine the success or failure of a vaccine and its immunological potency.

  1. Severe hypersensitivity reaction to minocycline.

    PubMed

    de Paz, S; Pérez, A; Gómez, M; Trampal, A; Domínguez Lázaro, A

    1999-01-01

    Minocycline is a tetracycline derivative mainly used in the treatment of acne vulgaris in young persons. Adverse events have been reported with minocycline, although it can be considered a safe drug. We report a case of severe hypersensitivity reaction to minocycline in a young patient. Laboratory examinations, chest X-ray, skin test and skin biopsy were performed. Oral challenge test with minocycline was not carried out as it can be hazardous. A case of severe reaction to minocycline is described in this article. The clinical and laboratory findings may be helpful in diagnosing similar reactions for which the immunological mechanisms are unknown. Moreover, this type of reaction must be recognized early due to the potential fatal outcome.

  2. Hypersensitivity reactions to vaccine components.

    PubMed

    Heidary, Noushin; Cohen, David E

    2005-09-01

    Vaccines are responsible for the control of many infectious diseases that were once common in the United States, including polio, measles, diphtheria, pertussis (whooping cough), rubella (German measles), mumps, tetanus, and Haemophilus influenzae type b. National efforts to generate collaboration between federal, state, and local governments and public and private health care providers have resulted in record high levels of vaccination coverage in the United States. The high rate of US vaccinations is paralleled by growing concerns about the safety of their delivery. The variety of substances used in vaccines sometimes causes the development of cutaneous reactions in susceptible adults and children. This article will review adverse cutaneous events consistent with hypersensitivity reactions to the following ingredients in vaccines: aluminum, thimerosal, 2-phenoxyethanol, formaldehyde, and neomycin.

  3. [Production of a dialysable transfer factor of cell mediated immunity by lymphoblastoid cells in continuous proliferation].

    PubMed

    Goust, J M; Viza, D; Moulias, R; Trejdosiewicz, L; Lesourd, B; Marescot, M R; Prévot, A

    1975-01-20

    Four lymphoblastoid cell lines tested in this work contain normally a dialysable moiety having by ultraviolet spectroscopy, column chromatography (Biogel P 10) and chemically the same properties than human dialysable Transfer Factor (TFd), but unable to transfer cell mediated immune response against common antigens. Two of them are able to do so after incubation with minimal amounts of TFd. Production of a molecule identical to human TFd is possible in some lymphoblastoid cell lines after induction with TFd. PMID:808340

  4. Reactive oxygen species as transducers of sphinganine-mediated cell death pathway

    PubMed Central

    Saucedo-García, Mariana; González-Solís, Ariadna; Rodríguez-Mejía, Priscila; de Jesús Olivera-Flores, Teresa; Vázquez-Santana, Sonia; Cahoon, Edgar B

    2011-01-01

    Long chain bases or sphingoid bases are building blocks of complex sphingolipids that display a signaling role in programmed cell death in plants. So far, the type of programmed cell death in which these signaling lipids have been demonstrated to participate is the cell death that occurs in plant immunity, known as the hypersensitive response. The few links that have been described in this pathway are: MPK6 activation, increased calcium concentrations and reactive oxygen species (ROS) generation. The latter constitute one of the more elusive loops because of the chemical nature of ROS, the multiple possible cell sites where they can be formed and the ways in which they influence cell structure and function. PMID:21921699

  5. Heparan sulfate mediates trastuzumab effect in breast cancer cells

    PubMed Central

    2013-01-01

    these resistant cells. Conclusion Trastuzumab action is dependent on the availability of heparan sulfate on the surface of breast cancer cells. Furthermore, our data suggest that high levels of heparan sulfate shed to the medium are able to capture trastuzumab, blocking the antibody action mediated by HER2. In addition to HER2 levels, heparan sulfate synthesis and shedding determine breast cancer cell susceptibility to trastuzumab. PMID:24083474

  6. Periaqueductal Grey EP3 Receptors Facilitate Spinal Nociception in Arthritic Secondary Hypersensitivity

    PubMed Central

    Drake, R.A.R.; Leith, J.L.; Almahasneh, F.; Martindale, J.; Wilson, A.W.; Lumb, B.

    2016-01-01

    hypersensitivity). This is found in many painful conditions, particularly arthritis. The periaqueductal gray (PAG) is an important center that controls spinal nociceptive processing, on which secondary hypersensitivity depends. Prostaglandins (PGs) are mediators of inflammation with pronociceptive actions within the PAG under normal conditions. We find that secondary hindpaw hypersensitivity in arthritic rats results from spinal sensitization to peripheral A-nociceptor inputs. In the PAG of arthritic, but not naive, rats, there is enhanced control of spinal A-nociceptor processing through PG EP3 receptors. The descending facilitatory actions of intra-PAG PGs play a direct and central role in the maintenance of inflammatory secondary hypersensitivity, particularly relating to the processing of A-fiber nociceptive information. PMID:27581447

  7. FLIP switches Fas-mediated glucose signaling in human pancreatic cells from apoptosis to cell replication

    NASA Astrophysics Data System (ADS)

    Maedler, Kathrin; Fontana, Adriano; Ris, Frédéric; Sergeev, Pavel; Toso, Christian; Oberholzer, José; Lehmann, Roger; Bachmann, Felix; Tasinato, Andrea; Spinas, Giatgen A.; Halban, Philippe A.; Donath, Marc Y.

    2002-06-01

    Type 2 diabetes mellitus results from an inadequate adaptation of the functional pancreatic cell mass in the face of insulin resistance. Changes in the concentration of glucose play an essential role in the regulation of cell turnover. In human islets, elevated glucose concentrations impair cell proliferation and induce cell apoptosis via up-regulation of the Fas receptor. Recently, it has been shown that the caspase-8 inhibitor FLIP may divert Fas-mediated death signals into those for cell proliferation in lymphatic cells. We observed expression of FLIP in human pancreatic cells of nondiabetic individuals, which was decreased in tissue sections of type 2 diabetic patients. In vitro exposure of islets from nondiabetic organ donors to high glucose levels decreased FLIP expression and increased the percentage of apoptotic terminal deoxynucleotidyltransferase-mediated UTP end labeling (TUNEL)-positive cells; FLIP was no longer detectable in such TUNEL-positive cells. Up-regulation of FLIP, by incubation with transforming growth factor or by transfection with an expression vector coding for FLIP, protected cells from glucose-induced apoptosis, restored cell proliferation, and improved cell function. The beneficial effects of FLIP overexpression were blocked by an antagonistic anti-Fas antibody, indicating their dependence on Fas receptor activation. The present data provide evidence for expression of FLIP in the human cell and suggest a novel approach to prevent and treat diabetes by switching Fas signaling from apoptosis to proliferation.

  8. NR2B Expression in Rat DRG Is Differentially Regulated Following Peripheral Nerve Injuries That Lead to Transient or Sustained Stimuli-Evoked Hypersensitivity

    PubMed Central

    Norcini, Monica; Sideris, Alexandra; Adler, Samantha M.; Hernandez, Lourdes A. M.; Zhang, Jin; Blanck, Thomas J. J.; Recio-Pinto, Esperanza

    2016-01-01

    Following injury, primary sensory neurons undergo changes that drive central sensitization and contribute to the maintenance of persistent hypersensitivity. NR2B expression in the dorsal root ganglia (DRG) has not been previously examined in neuropathic pain models. Here, we investigated if changes in NR2B expression within the DRG are associated with hypersensitivities that result from peripheral nerve injuries. This was done by comparing the NR2B expression in the DRG derived from two modalities of the spared nerve injury (SNI) model, since each variant produces different neuropathic pain phenotypes. Using the electronic von Frey to stimulate the spared and non-spared regions of the hindpaws, we demonstrated that sural-SNI animals develop sustained neuropathic pain in both regions while the tibial-SNI animals recover. NR2B expression was measured at Day 23 and Day 86 post-injury. At Day 23 and 86 post-injury, sural-SNI animals display strong hypersensitivity, whereas tibial-SNI animals display 50 and 100% recovery from post-injury-induced hypersensitivity, respectively. In tibial-SNI at Day 86, but not at Day 23 the perinuclear region of the neuronal somata displayed an increase in NR2B protein. This retention of NR2B protein within the perinuclear region, which will render them non-functional, correlates with the recovery observed in tibial-SNI. In sural-SNI at Day 86, DRG displayed an increase in NR2B mRNA which correlates with the development of sustained hypersensitivity in this model. The increase in NR2B mRNA was not associated with an increase in NR2B protein within the neuronal somata. The latter may result from a decrease in kinesin Kif17, since Kif17 mediates NR2B transport to the soma’s plasma membrane. In both SNIs, microglia/macrophages showed a transient increase in NR2B protein detected at Day 23 but not at Day 86, which correlates with the initial post-injury induced hypersensitivity in both SNIs. In tibial-SNI at Day 86, but not at Day 23

  9. Biomineralization mediated by anaerobic methane-consuming cell consortia

    PubMed Central

    Chen, Ying; Li, Yi-Liang; Zhou, Gen-Tao; Li, Han; Lin, Yang-Ting; Xiao, Xiang; Wang, Feng-Ping

    2014-01-01

    Anaerobic methanotrophic archaea (ANME) play a significant role in global carbon cycles. These organisms consume more than 90% of ocean-derived methane and influence the landscape of the seafloor by stimulating the formation of carbonates. ANME frequently form cell consortia with sulfate-reducing bacteria (SRB) of the family Deltaproteobacteria. We investigated the mechanistic link between ANME and the natural consortium by examining anaerobic oxidation of methane (AOM) metabolism and the deposition of biogenetic minerals through high-resolution imaging analysis. All of the cell consortia found in a sample of marine sediment were encrusted by a thick siliceous envelope consisting of laminated and cementing substances, whereas carbonate minerals were not found attached to cells. Beside SRB cells, other bacteria (such as Betaproteobacteria) were found to link with the consortia by adhering to the siliceous crusts. Given the properties of siliceous minerals, we hypothesize that ANME cell consortia can interact with other microorganisms and their substrates via their siliceous envelope, and this mechanism of silicon accumulation may serve in clay mineral formation in marine sedimentary environments. A mechanism for biomineralization mediated by AOM consortia was suggested based on the above observations. PMID:25027246

  10. Biomineralization mediated by anaerobic methane-consuming cell consortia.

    PubMed

    Chen, Ying; Li, Yi-Liang; Zhou, Gen-Tao; Li, Han; Lin, Yang-Ting; Xiao, Xiang; Wang, Feng-Ping

    2014-01-01

    Anaerobic methanotrophic archaea (ANME) play a significant role in global carbon cycles. These organisms consume more than 90% of ocean-derived methane and influence the landscape of the seafloor by stimulating the formation of carbonates. ANME frequently form cell consortia with sulfate-reducing bacteria (SRB) of the family Deltaproteobacteria. We investigated the mechanistic link between ANME and the natural consortium by examining anaerobic oxidation of methane (AOM) metabolism and the deposition of biogenetic minerals through high-resolution imaging analysis. All of the cell consortia found in a sample of marine sediment were encrusted by a thick siliceous envelope consisting of laminated and cementing substances, whereas carbonate minerals were not found attached to cells. Beside SRB cells, other bacteria (such as Betaproteobacteria) were found to link with the consortia by adhering to the siliceous crusts. Given the properties of siliceous minerals, we hypothesize that ANME cell consortia can interact with other microorganisms and their substrates via their siliceous envelope, and this mechanism of silicon accumulation may serve in clay mineral formation in marine sedimentary environments. A mechanism for biomineralization mediated by AOM consortia was suggested based on the above observations. PMID:25027246

  11. NKG2D ligands mediate immunosurveillance of senescent cells.

    PubMed

    Sagiv, Adi; Burton, Dominick G A; Moshayev, Zhana; Vadai, Ezra; Wensveen, Felix; Ben-Dor, Shifra; Golani, Ofra; Polic, Bojan; Krizhanovsky, Valery

    2016-02-01

    Cellular senescence is a stress response mechanism that limits tumorigenesis and tissue damage. Induction of cellular senescence commonly coincides with an immunogenic phenotype that promotes self-elimination by components of the immune system, thereby facilitating tumor suppression and limiting excess fibrosis during wound repair. The mechanisms by which senescent cells regulate their immune surveillance are not completely understood. Here we show that ligands of an activating Natural Killer (NK) cell receptor (NKG2D), MICA and ULBP2 are consistently up-regulated following induction of replicative senescence, oncogene-induced senescence and DNA damage - induced senescence. MICA and ULBP2 proteins are necessary for efficient NK-mediated cytotoxicity towards senescent fibroblasts. The mechanisms regulating the initial expression of NKG2D ligands in senescent cells are dependent on a DNA damage response, whilst continuous expression of these ligands is regulated by the ERK signaling pathway. In liver fibrosis, the accumulation of senescent activated stellate cells is increased in mice lacking NKG2D receptor leading to increased fibrosis. Overall, our results provide new insights into the mechanisms regulating the expression of immune ligands in senescent cells and reveal the importance of NKG2D receptor-ligand interaction in protecting against liver fibrosis. PMID:26878797

  12. Stem and progenitor cell-mediated tumor selective gene therapy.

    PubMed

    Aboody, K S; Najbauer, J; Danks, M K

    2008-05-01

    The poor prognosis for patients with aggressive or metastatic tumors and the toxic side effects of currently available treatments necessitate the development of more effective tumor-selective therapies. Stem/progenitor cells display inherent tumor-tropic properties that can be exploited for targeted delivery of anticancer genes to invasive and metastatic tumors. Therapeutic genes that have been inserted into stem cells and delivered to tumors with high selectivity include prodrug-activating enzymes (cytosine deaminase, carboxylesterase, thymidine kinase), interleukins (IL-2, IL-4, IL-12, IL-23), interferon-beta, apoptosis-promoting genes (tumor necrosis factor-related apoptosis-inducing ligand) and metalloproteinases (PEX). We and others have demonstrated that neural and mesenchymal stem cells can deliver therapeutic genes to elicit a significant antitumor response in animal models of intracranial glioma, medulloblastoma, melanoma brain metastasis, disseminated neuroblastoma and breast cancer lung metastasis. Most studies reported reduction in tumor volume (up to 90%) and increased survival of tumor-bearing animals. Complete cures have also been achieved (90% disease-free survival for >1 year of mice bearing disseminated neuroblastoma tumors). As we learn more about the biology of stem cells and the molecular mechanisms that mediate their tumor-tropism and we identify efficacious gene products for specific tumor types, the clinical utility of cell-based delivery strategies becomes increasingly evident.

  13. Paneth cell-mediated multiorgan dysfunction after acute kidney injury

    PubMed Central

    Park, Sang Won; Kim, Mihwa; Kim, Joo Yun; Ham, Ahrom; Brown, Kevin M.; Mori-Akiyama, Yuko; Ouellette, André J.; D’Agati, Vivette D.; Lee, H. Thomas

    2012-01-01

    Acute kidney injury (AKI) is frequently complicated by extra-renal multi-organ injury including intestinal and hepatic dysfunction. In this study, we hypothesized that a discrete intestinal source of pro-inflammatory mediators drives multi-organ injury in response to AKI. After induction of AKI in mice by renal ischemia-reperfusion or bilateral nephrectomy, small intestinal Paneth cells increased the synthesis and release of IL-17A in conjunction with severe intestinal apoptosis and inflammation. We also detected significantly increased IL-17A in portal and systemic circulation after AKI. Intestinal macrophages appear to transport released Paneth cell granule constituents induced by AKI, away from the base of the crypts into the liver. Genetic or pharmacologic depletion of Paneth cells decreased small intestinal IL-17A secretion and plasma IL-17A levels significantly and attenuated intestinal, hepatic, and renal injury after AKI. Similarly, portal delivery of IL-17A in macrophage depleted mice decreased markedly, and intestinal, hepatic, and renal injury following AKI was attenuated without affecting intestinal IL-17A generation. In conclusion, AKI induces IL-17A synthesis and secretion by Paneth cells to initiate intestinal and hepatic injury by hepatic and systemic delivery of IL-17A by macrophages. Modulation of Paneth cell dysregulation may have therapeutic implications by reducing systemic complications arising from AKI. PMID:23109723

  14. Interstitial cells of Cajal mediate mechanosensitive responses in the stomach

    NASA Astrophysics Data System (ADS)

    Won, Kyung-Jong; Sanders, Kenton M.; Ward, Sean M.

    2005-10-01

    Changes in motor activity are a basic response to filling of smooth muscle organs. Responses to gastric filling, for example, are thought to be regulated by neural reflexes. Here, we demonstrate a previously uncharacterized aspect of stretch-dependent responses in visceral smooth muscles that is mediated by mechanosensitive interstitial cells of Cajal. Length ramps were applied to the murine antral muscles while recording intracellular electrical activity and isometric force. Stretching muscles by an average of 27 ± 1% of resting length resulted in 5 mN of force. Increasing length caused membrane depolarization and increased slow-wave frequency. The responses were dependent on the rate of stretch. Stretch-dependent responses were not inhibited by neuronal antagonists or nifedipine. Increases in slow-wave frequency, but not membrane depolarization, were inhibited by reducing external Ca2+ (100 μM) and by Ni2+ (250 μM). Responses to stretch were inhibited by indomethacin (1 μM) and were absent in cyclooxygenase II-deficient mice, suggesting that cyclooxygenase II-derived eicosanoids may mediate these responses. Dual microelectrode impalements of muscle cells within the corpus and antrum showed that stretch-induced changes in slow-wave frequency uncoupled proximal-to-distal propagation of slow waves. This uncoupling could interfere with gastric peristalsis and impede gastric emptying. Stretch of antral muscles of W/WV mice, which lack intramuscular interstitial cells of Cajal, did not affect membrane depolarization or slow-wave frequency. These data demonstrate a previously uncharacterized nonneural stretch reflex in gastric muscles and provide physiological evidence demonstrating a mechanosensitive role for interstitial cells of Cajal in smooth muscle tissues. gastric compliance | pacemaker | stretch | slow waves | propagation

  15. scid mutation in mice confers hypersensitivity to ionizing radiation and a deficiency in DNA double-strand break repair

    SciTech Connect

    Biedermann, K.A.; Sun, J.R.; Giaccia, A.J.; Tosto, L.M.; Brown, J.M. )

    1991-02-15

    C.B-17 severe combined immunodeficient (scid) mice carry the scid mutation and are severely deficient in both T cell- and B cell-mediated immunity, apparently as a result of defective V(D)J joining of the immunoglobulin and T-cell receptor gene elements. In the present studies, we have defined the tissue, cellular, and molecular basis of another characteristic of these mice: their hypersensitivity to ionizing radiation. Bone marrow stem cells, intestinal crypt cells, and epithelial skin cells from scid mice are 2- to 3-fold more sensitive when irradiated in situ than are congenic BALB/c or C.B-17 controls. Two independently isolated embryo fibroblastic scid mouse cell lines display similar hypersensitivities to gamma-rays. In addition, these cell lines are sensitive to cell killing by bleomycin, which also produces DNA strand breaks, but not by the DNA crosslinking agent mitomycin C or UV irradiation. Measurement of the rejoining of gamma-ray-induced DNA double-strand breaks by pulsed-field gel electrophoresis indicates that these animals are defective in this repair system. This suggests that the gamma-ray sensitivity of the scid mouse fibroblasts could be the result of reduced repair of DNA double-strand breaks. Therefore, a common factor may participate in both the repair of DNA double-strand breaks as well as V(D)J rejoining during lymphocyte development. This murine autosomal recessive mutation should prove extremely useful in fundamental studies of radiation-induced DNA damage and repair.

  16. Rho GTPase activity modulates paramyxovirus fusion protein-mediated cell-cell fusion

    SciTech Connect

    Schowalter, Rachel M.; Wurth, Mark A.; Aguilar, Hector C.; Lee, Benhur; Moncman, Carole L.; McCann, Richard O.; Dutch, Rebecca Ellis . E-mail: rdutc2@uky.edu

    2006-07-05

    The paramyxovirus fusion protein (F) promotes fusion of the viral envelope with the plasma membrane of target cells as well as cell-cell fusion. The plasma membrane is closely associated with the actin cytoskeleton, but the role of actin dynamics in paramyxovirus F-mediated membrane fusion is unclear. We examined cell-cell fusion promoted by two different paramyxovirus F proteins in three cell types in the presence of constitutively active Rho family GTPases, major cellular coordinators of actin dynamics. Reporter gene and syncytia assays demonstrated that expression of either Rac1{sup V12} or Cdc42{sup V12} could increase cell-cell fusion promoted by the Hendra or SV5 glycoproteins, though the effect was dependent on the cell type expressing the viral glycoproteins. In contrast, RhoA{sup L63} decreased cell-cell fusion promoted by Hendra glycoproteins but had little affect on SV5 F-mediated fusion. Also, data suggested that GTPase activation in the viral glycoprotein-containing cell was primarily responsible for changes in fusion. Additionally, we found that activated Cdc42 promoted nuclear rearrangement in syncytia.

  17. Hepatic non-parenchymal cells and extracellular matrix participate in oval cell-mediated liver regeneration

    PubMed Central

    Zhang, Wei; Chen, Xiao-Ping; Zhang, Wan-Guang; Zhang, Feng; Xiang, Shuai; Dong, Han-Hua; Zhang, Lei

    2009-01-01

    AIM: To elucidate the interaction between non-parenchymal cells, extracellular matrix and oval cells during the restituting process of liver injury induced by partial hepatectomy (PH). METHODS: We examined the localization of oval cells, non-parenchymal cells, and the extracellular matrix components using immunohistochemical and double immunofluorescent analysis during the proliferation and differentiation of oval cells in N-2-acetylaminofluorene (2-AAF)/PH rat model. RESULTS: By day 2 after PH, small oval cells began to proliferate around the portal area. Most of stellate cells and laminin were present along the hepatic sinusoids in the periportal area. Kupffer cells and fibronectin markedly increased in the whole hepatic lobule. From day 4 to 9, oval cells spread further into hepatic parenchyma, closely associated with stellate cells, fibronectin and laminin. Kupffer cells admixed with oval cells by day 6 and then decreased in the periportal zone. From day 12 to 15, most of hepatic stellate cells (HSCs), laminin and fibronectin located around the small hepatocyte nodus, and minority of them appeared in the nodus. Kupffer cells were mainly limited in the pericentral sinusoids. After day 18, the normal liver lobule structures began to recover. CONCLUSION: Local hepatic microenvironment may participate in the oval cell-mediated liver regeneration through the cell-cell and cell-matrix interactions. PMID:19195056

  18. Amphiregulin mediates self-renewal in an immortal mammary epithelial cell line with stem cell characteristics

    SciTech Connect

    Booth, Brian W.; Boulanger, Corinne A.; Anderson, Lisa H.; Jimenez-Rojo, Lucia; Brisken, Cathrin; Smith, Gilbert H.

    2010-02-01

    Amphiregulin (AREG), a ligand for epidermal growth factor receptor, is required for mammary gland ductal morphogenesis and mediates estrogen actions in vivo, emerging as an essential growth factor during mammary gland growth and differentiation. The COMMA-D {beta}-geo (CD{beta}geo) mouse mammary cell line displays characteristics of normal mammary progenitor cells including the ability to regenerate a mammary gland when transplanted into the cleared fat pad of a juvenile mouse, nuclear label retention, and the capacity to form anchorage-independent mammospheres. We demonstrate that AREG is essential for formation of floating mammospheres by CD{beta}geo cells and that the mitogen activated protein kinase signaling pathway is involved in AREG-mediated mammosphere formation. Addition of exogenous AREG promotes mammosphere formation in cells where AREG expression is knocked down by siRNA and mammosphere formation by AREG{sup -/-} mammary epithelial cells. AREG knockdown inhibits mammosphere formation by duct-limited mammary progenitor cells but not lobule-limited mammary progenitor cells. These data demonstrate AREG mediates the function of a subset of mammary progenitor cells in vitro.

  19. Adrenergic stimulation sensitizes TRPV1 through upregulation of cystathionine β-synthetase in a rat model of visceral hypersensitivity.

    PubMed

    Zhu, Liyan; Zhao, Liting; Qu, Ruobing; Zhu, Hong-Yan; Wang, Yongmeng; Jiang, Xinghong; Xu, Guang-Yin

    2015-11-03

    The pathogenesis of pain in irritable bowel syndrome (IBS) is poorly understood and treatment remains difficult. The present study was designed to investigate roles of adrenergic signaling and the endogenous hydrogen sulfide producing enzyme cystathionine β-synthetase (CBS) in a previously validated rat model of IBS induced by neonatal colonic inflammation (NCI). Here we showed that NCI-induced visceral hypersensitivity (VH) was significantly attenuated by β2 subunit inhibitor but not by β1 or β3 or α subunit inhibitor. NCI markedly elevated plasma norepinephrine (NE) concentration without alteration in expression of β2 subunit receptors in dorsal root ganglion (DRGs) innervating the colon. In addition, NCI markedly enhanced TRPV1 and CBS expression in the colon DRGs. CBS inhibitor AOAA reversed the upregulation of TRPV1 in NCI rats. In vitro experiments showed that incubation of DRG cells with NE markedly enhanced expression of TRPV1, which was reversed by application of AOAA. Incubation of DRG cells with the H2S donor NaHS greatly enhanced TRPV1 expression. Collectively, these data suggest that activation of adrenergic signaling by NCI sensitizes TRPV1 channel activity, which is likely mediated by upregulation of CBS expression in peripheral sensory neurons, thus contributing to chronic visceral hypersensitivity.

  20. A naturally hypersensitive glucocorticoid receptor elicits a compensatory reduction of hypothalamus–pituitary–adrenal axis activity early in ontogeny

    PubMed Central

    Muráni, Eduard; Ponsuksili, Siriluck; Jaeger, Alexandra; Görres, Andreas; Tuchscherer, Armin; Wimmers, Klaus

    2016-01-01

    We comprehensively characterized the effects of a unique natural gain-of-function mutation in the glucocorticoid receptor (GR), GRAla610Val, in domestic pigs to expand current knowledge of the phenotypic consequences of GR hypersensitivity. Cortisol levels were consistently reduced in one-week-old piglets, at weaning and in peripubertal age, probably due to a reduced adrenal capacity to produce glucocorticoids (GC), which was indicated by an adrenocortical thinning in GRAla610Val carriers. Adrenocorticotrophic hormone (ACTH) levels were significantly reduced in one-week-old piglets only. Expression analyses in peripubertal age revealed significant downregulation of hypothalamic expression of CRH and AVP, the latter only in females, and upregulation of hepatic expression of SERPINA6, by GRAla610Val. Transcriptional repression of proinflammatory genes in peripheral blood mononuclear cells (PBMCs) from GRAla610Val carriers was more sensitive to dexamethasone treatment ex vivo. However, no significant effects on growth, body composition, blood chemistry or cell counts were observed under baseline conditions. These results suggest that GRAla610Val-induced GR hypersensitivity elicits a compensatory reduction in endogenous, bioactive glucocorticoid levels via readjustment of the hypothalamus–pituitary–adrenal (HPA) axis early in ontogeny to maintain an adequate response, but carriers are more sensitive to exogenous GC. Therefore, GRAla610Val pigs represent a valuable animal model to explore GR-mediated mechanisms of HPA axis regulation and responses to glucocorticoid-based drugs. PMID:27440422

  1. Adrenergic stimulation sensitizes TRPV1 through upregulation of cystathionine β-synthetase in a rat model of visceral hypersensitivity.

    PubMed

    Zhu, Liyan; Zhao, Liting; Qu, Ruobing; Zhu, Hong-Yan; Wang, Yongmeng; Jiang, Xinghong; Xu, Guang-Yin

    2015-01-01

    The pathogenesis of pain in irritable bowel syndrome (IBS) is poorly understood and treatment remains difficult. The present study was designed to investigate roles of adrenergic signaling and the endogenous hydrogen sulfide producing enzyme cystathionine β-synthetase (CBS) in a previously validated rat model of IBS induced by neonatal colonic inflammation (NCI). Here we showed that NCI-induced visceral hypersensitivity (VH) was significantly attenuated by β2 subunit inhibitor but not by β1 or β3 or α subunit inhibitor. NCI markedly elevated plasma norepinephrine (NE) concentration without alteration in expression of β2 subunit receptors in dorsal root ganglion (DRGs) innervating the colon. In addition, NCI markedly enhanced TRPV1 and CBS expression in the colon DRGs. CBS inhibitor AOAA reversed the upregulation of TRPV1 in NCI rats. In vitro experiments showed that incubation of DRG cells with NE markedly enhanced expression of TRPV1, which was reversed by application of AOAA. Incubation of DRG cells with the H2S donor NaHS greatly enhanced TRPV1 expression. Collectively, these data suggest that activation of adrenergic signaling by NCI sensitizes TRPV1 channel activity, which is likely mediated by upregulation of CBS expression in peripheral sensory neurons, thus contributing to chronic visceral hypersensitivity. PMID:26527188

  2. Ralstonia solanacearum type III secretion system effector Rip36 induces a hypersensitive response in the nonhost wild eggplant Solanum torvum.

    PubMed

    Nahar, Kamrun; Matsumoto, Iyo; Taguchi, Fumiko; Inagaki, Yoshishige; Yamamoto, Mikihiro; Toyoda, Kazuhiro; Shiraishi, Tomonori; Ichinose, Yuki; Mukaihara, Takafumi

    2014-04-01

    Ralstonia solanacearum is a Gram-negative soil-borne bacterium that causes bacterial wilt disease in more than 200 plant species, including economically important Solanaceae species. In R. solanacearum, the hypersensitive response and pathogenicity (Hrp) type III secretion system is required for both the ability to induce the hypersensitive response (HR) in nonhost plants and pathogenicity in host plants. Recently, 72 effector genes, called rip (Ralstonia protein injected into plant cells), have been identified in R. solanacearum RS1000. RS1002, a spontaneous nalixidic acid-resistant derivative of RS1000, induced strong HR in the nonhost wild eggplant Solanum torvum in an Hrp-dependent manner. An Agrobacterium-mediated transient expression system revealed that Rip36, a putative Zn-dependent protease effector of R. solanacearum, induced HR in S. torvum. A mutation in the putative Zn-binding motif (E149A) completely abolished the ability to induce HR. In agreement with this result, the RS1002-derived Δrip36 and rip36E149A mutants lost the ability to induce HR in S. torvum. An E149A mutation had no effect on the translocation of Rip36 into plant cells. These results indicate that Rip36 is an avirulent factor that induces HR in S. torvum and that a putative Zn-dependent protease motif is essential for this activity.

  3. Adrenergic stimulation sensitizes TRPV1 through upregulation of cystathionine β-synthetase in a rat model of visceral hypersensitivity

    PubMed Central

    Zhu, Liyan; Zhao, Liting; Qu, Ruobing; Zhu, Hong-Yan; Wang, Yongmeng; Jiang, Xinghong; Xu, Guang-Yin

    2015-01-01

    The pathogenesis of pain in irritable bowel syndrome (IBS) is poorly understood and treatment remains difficult. The present study was designed to investigate roles of adrenergic signaling and the endogenous hydrogen sulfide producing enzyme cystathionine β-synthetase (CBS) in a previously validated rat model of IBS induced by neonatal colonic inflammation (NCI). Here we showed that NCI-induced visceral hypersensitivity (VH) was significantly attenuated by β2 subunit inhibitor but not by β1 or β3 or α subunit inhibitor. NCI markedly elevated plasma norepinephrine (NE) concentration without alteration in expression of β2 subunit receptors in dorsal root ganglion (DRGs) innervating the colon. In addition, NCI markedly enhanced TRPV1 and CBS expression in the colon DRGs. CBS inhibitor AOAA reversed the upregulation of TRPV1 in NCI rats. In vitro experiments showed that incubation of DRG cells with NE markedly enhanced expression of TRPV1, which was reversed by application of AOAA. Incubation of DRG cells with the H2S donor NaHS greatly enhanced TRPV1 expression. Collectively, these data suggest that activation of adrenergic signaling by NCI sensitizes TRPV1 channel activity, which is likely mediated by upregulation of CBS expression in peripheral sensory neurons, thus contributing to chronic visceral hypersensitivity. PMID:26527188

  4. Extraordinarily few organisms of a live recombinant BCG vaccine against tuberculosis induce maximal cell-mediated and protective immunity.

    PubMed

    Horwitz, Marcus A; Harth, Günter; Dillon, Barbara Jane; Maslesa-Galić, Sasa

    2006-01-23

    In previous studies, we have described a live recombinant BCG vaccine (rBCG30) overexpressing the 30 kDa major secretory protein of Mycobacterium tuberculosis that induces greater protective immunity against tuberculosis than the current vaccine in the demanding guinea pig model of pulmonary tuberculosis. In this study, we have investigated the impact of vaccine dose on the development of cell-mediated and protective immunity in the guinea pig model. We found that the protective efficacy against M. tuberculosis aerosol challenge of both BCG and rBCG30 was essentially dose-independent over a dose range of 10(1)-10(6) live organisms. As previously observed, rBCG30 was more potent, reducing colony-forming units (CFU) below the level observed in animals immunized with the parental BCG vaccine by 0.7 logs in the lungs and 1.0 logs in the spleen (P<0.0001). To gain a better understanding of the influence of dose on bacterial clearance and immunity, we assessed animals immunized with 10(1), 10(3), or 10(6)CFU of rBCG30. The higher the dose, the higher the peak CFU level achieved in animal organs. However, whereas humoral immune responses to the 30 kDa protein reflected the disparate CFU levels, cell-mediated immune responses did not; high and low doses of rBCG30 ultimately induced comparable peak lymphocyte proliferative responses and cutaneous delayed-type hypersensitivity responses to the 30 kDa protein. We estimate that the amount of the 30 kDa protein required to induce a strong cell-mediated immune response when delivered via 10 rBCG30 organisms is about 9 orders of magnitude less than that required when the protein is delivered in a conventional protein/adjuvant vaccine. This study demonstrates that a very low inoculum of rBCG30 organisms has the capacity to induce strong protective immunity against tuberculosis and that rBCG30 is an extremely potent delivery system for mycobacterial antigens.

  5. Spinal actions of lipoxin A4 and 17(R)-resolvin D1 attenuate inflammation-induced mechanical hypersensitivity and spinal TNF release.

    PubMed

    Abdelmoaty, Sally; Wigerblad, Gustaf; Bas, Duygu B; Codeluppi, Simone; Fernandez-Zafra, Teresa; El-Awady, El-Sayed; Moustafa, Yasser; Abdelhamid, Alaa El-Din S; Brodin, Ernst; Svensson, Camilla I

    2013-01-01

    Lipoxins and resolvins have anti-inflammatory and pro-resolving actions and accumulating evidence indicates that these lipid mediators also attenuate pain-like behavior in a number of experimental models of inflammation and tissue injury-induced pain. The present study was undertaken to assess if spinal administration of lipoxin A4 (LXA4) or 17 (R)-resolvin D1 (17(R)-RvD1) attenuates mechanical hypersensitivity in the carrageenan model of peripheral inflammation in the rat. Given the emerging role of spinal cytokines in the generation and maintenance of inflammatory pain we measured cytokine levels in the cerebrospinal fluid (CSF) after LXA4 or 17(R)-RvD1 administration, and the ability of these lipid metabolites to prevent stimuli-induced release of cytokines from cultured primary spinal astrocytes. We found that intrathecal bolus injection of LXA4 and17(R)-RvD1 attenuated inflammation-induced mechanical hypersensitivity without reducing the local inflammation. Furthermore, both LXA4 and 17(R)-RvD1 reduced carrageenan-induced tumor necrosis factor (TNF) release in the CSF, while only 17(R)-RvD1attenuated LPS and IFN-γ-induced TNF release in astrocyte cell culture. In conclusion, this study demonstrates that lipoxins and resolvins potently suppress inflammation-induced mechanical hypersensitivity, possibly by attenuating cytokine release from spinal astrocytes. The inhibitory effect of lipoxins and resolvins on spinal nociceptive processing puts them in an intriguing position in the search for novel pain therapeutics.

  6. Hydralazine rescues PC12 cells from acrolein-mediated death.

    PubMed

    Liu-Snyder, Peishan; Borgens, Richard Ben; Shi, Riyi

    2006-07-01

    Acrolein, a major lipid peroxidation product, has been associated with both CNS trauma and neurodegenerative diseases. Because of its long half-life, acrolein is a potent endogenous toxin capable of killing healthy cells during the secondary injury process. Traditionally, attempts to intervene in the process of progressive cell death after the primary injury have included scavenging reactive oxygen species (so-called free radicals). The animal data supporting such an approach have generally been positive, but all human clinical trials attempting a similar outcome in human CNS injury have failed. New drugs that might reduce toxicity by scavenging the products of lipid peroxidation present a promising, and little investigated, therapeutic approach. Hydralazine, a well-known treatment for hypertension, has been reported to react with acrolein, forming hydrazone in cell-free systems. In the companion paper, we have established an acrolein-mediated cell injury model using PC12 cells in vitro. Here we test the hypothesis that the formation of hydrazone adducts with acrolein is able to reduce acrolein toxicity and spare a significant percentage of the population of PC12 cells from death. Concentrations of approximately 1 mM of this aldehyde scavenger can rescue over 80% of the population of PC12 cells. This study provides a basis for a new pharmacological treatment to reduce the effects of secondary injury in the damaged and/or diseased nervous system. In particular, we describe the need for new drugs that possess aldehyde scavenging properties but do not interfere with the regulation of blood pressure.

  7. Alpha-adrenergic blocker mediated osteoblastic stem cell differentiation

    SciTech Connect

    Choi, Yoon Jung; Lee, Jue Yeon; Lee, Seung Jin; Chung, Chong-Pyoung; Park, Yoon Jeong

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer Doxazocin directly up-regulated bone metabolism at a low dose. Black-Right-Pointing-Pointer Doxazocin induced osteoblastic stem cell differentiation without affecting cell proliferation. Black-Right-Pointing-Pointer This osteogenic stem cell differentiation is mediated by ERK-signal dependent pathway. -- Abstract: Recent researches have indicated a role for antihypertensive drugs including alpha- or beta-blockers in the prevention of bone loss. Some epidemiological studies reported the protective effects of those agents on fracture risk. However, there is limited information on the association with those agents especially at the mechanism of action. In the present study, we investigated the effects of doxazosin, an alpha-blocker that is clinically used for the treatment of benign prostatic hyperplasia (BPH) along with antihypertensive medication, on the osteogenic stem cell differentiation. We found that doxazosin increased osteogenic differentiation of human mesenchymal stem cells, detected by Alizarin red S staining and calcein. Doxazosin not only induced expression of alkaline phosphatase, type I collagen, osteopontin, and osteocalcin, it also resulted in increased phosphorylation of extracellular signal-regulated kinase (ERK1/2), a MAP kinase involved in osteoblastic differentiation. Treatment with U0126, a MAP kinase inhibitor, significantly blocked doxazosin-induced osteoblastic differentiation. Unrelated to activation of osteogenic differentiation by doxazosin, we found that there were no significant changes in adipogenic differentiation or in the expression of adipose-specific genes, including peroxisome proliferator-activated receptor {gamma}, aP2, or LPL. In this report, we suggest that doxazosin has the ability to increase osteogenic cell differentiation via ERK1/2 activation in osteogenic differentiation of adult stem cells, which supports the protective effects of antihypertensive drug on fracture risk and

  8. Long-term moderate calorie restriction inhibits inflammation without impairing cell-mediated immunity: a randomized controlled trial in non-obese humans.

    PubMed

    Meydani, Simin N; Das, Sai K; Pieper, Carl F; Lewis, Michael R; Klein, Sam; Dixit, Vishwa D; Gupta, Alok K; Villareal, Dennis T; Bhapkar, Manjushri; Huang, Megan; Fuss, Paul J; Roberts, Susan B; Holloszy, John O; Fontana, Luigi

    2016-07-01

    Calorie restriction (CR) inhibits inflammation and slows aging in many animal species, but in rodents housed in pathogen-free facilities, CR impairs immunity against certain pathogens. However, little is known about the effects of long-term moderate CR on immune function in humans. In this multi-center, randomized clinical trial to determine CR's effect on inflammation and cell-mediated immunity, 218 healthy non-obese adults (20-50 y), were assigned 25% CR (n=143) or an ad-libitum (AL) diet (n=75), and outcomes tested at baseline, 12, and 24 months of CR. CR induced a 10.4% weight loss over the 2-y period. Relative to AL group, CR reduced circulating inflammatory markers, including total WBC and lymphocyte counts, ICAM-1 and leptin. Serum CRP and TNF-α concentrations were about 40% and 50% lower in CR group, respectively. CR had no effect on the delayed-type hypersensitivity skin response or antibody response to vaccines, nor did it cause difference in clinically significant infections. In conclusion, long-term moderate CR without malnutrition induces a significant and persistent inhibition of inflammation without impairing key in vivo indicators of cell-mediated immunity. Given the established role of these pro-inflammatory molecules in the pathogenesis of multiple chronic diseases, these CR-induced adaptations suggest a shift toward a healthy phenotype. PMID:27410480

  9. Long-term moderate calorie restriction inhibits inflammation without impairing cell-mediated immunity: a randomized controlled trial in non-obese humans.

    PubMed

    Meydani, Simin N; Das, Sai K; Pieper, Carl F; Lewis, Michael R; Klein, Sam; Dixit, Vishwa D; Gupta, Alok K; Villareal, Dennis T; Bhapkar, Manjushri; Huang, Megan; Fuss, Paul J; Roberts, Susan B; Holloszy, John O; Fontana, Luigi

    2016-07-01

    Calorie restriction (CR) inhibits inflammation and slows aging in many animal species, but in rodents housed in pathogen-free facilities, CR impairs immunity against certain pathogens. However, little is known about the effects of long-term moderate CR on immune function in humans. In this multi-center, randomized clinical trial to determine CR's effect on inflammation and cell-mediated immunity, 218 healthy non-obese adults (20-50 y), were assigned 25% CR (n=143) or an ad-libitum (AL) diet (n=75), and outcomes tested at baseline, 12, and 24 months of CR. CR induced a 10.4% weight loss over the 2-y period. Relative to AL group, CR reduced circulating inflammatory markers, including total WBC and lymphocyte counts, ICAM-1 and leptin. Serum CRP and TNF-α concentrations were about 40% and 50% lower in CR group, respectively. CR had no effect on the delayed-type hypersensitivity skin response or antibody response to vaccines, nor did it cause difference in clinically significant infections. In conclusion, long-term moderate CR without malnutrition induces a significant and persistent inhibition of inflammation without impairing key in vivo indicators of cell-mediated immunity. Given the established role of these pro-inflammatory molecules in the pathogenesis of multiple chronic diseases, these CR-induced adaptations suggest a shift toward a healthy phenotype.

  10. Long-term moderate calorie restriction inhibits inflammation without impairing cell-mediated immunity: a randomized controlled trial in non-obese humans

    PubMed Central

    Meydani, Simin N.; Das, Sai K.; Pieper, Carl F.; Lewis, Michael R.; Klein, Sam; Dixit, Vishwa D.; Gupta, Alok K.; Villareal, Dennis T.; Bhapkar, Manjushri; Huang, Megan; Fuss, Paul J.; Roberts, Susan B.; Holloszy, John O.; Fontana, Luigi

    2016-01-01

    Calorie restriction (CR) inhibits inflammation and slows aging in many animal species, but in rodents housed in pathogen-free facilities, CR impairs immunity against certain pathogens. However, little is known about the effects of long-term moderate CR on immune function in humans. In this multi-center, randomized clinical trial to determine CR's effect on inflammation and cell-mediated immunity, 218 healthy non-obese adults (20-50 y), were assigned 25% CR (n=143) or an ad-libitum (AL) diet (n=75), and outcomes tested at baseline, 12, and 24 months of CR. CR induced a 10.4% weight loss over the 2-y period. Relative to AL group, CR reduced circulating inflammatory markers, including total WBC and lymphocyte counts, ICAM-1 and leptin. Serum CRP and TNF-α concentrations were about 40% and 50% lower in CR group, respectively. CR had no effect on the delayed-type hypersensitivity skin response or antibody response to vaccines, nor did it cause difference in clinically significant infections. In conclusion, long-term moderate CR without malnutrition induces a significant and persistent inhibition of inflammation without impairing key in vivo indicators of cell-mediated immunity. Given the established role of these pro-inflammatory molecules in the pathogenesis of multiple chronic diseases, these CR-induced adaptations suggest a shift toward a healthy phenotype. PMID:27410480

  11. DELAYED HYPERSENSITIVITY TO HAPTEN-PROTEIN CONJUGATES

    PubMed Central

    Cell, P. G. H.; Silverstein, Arthur M.

    1962-01-01

    Further data have been presented showing that the specificity of the delayed hypersensitivity reaction in the guinea pig to hapten-protein conjugates involves to a considerable degree a contribution by the protein carrier. The carrier contribution is such that sensitization to guinea pig albumin-m-azobenzenesulfonate, for example, does not result in cross-reaction with conjugates of the same hapten with unrelated proteins such as ovalbumin or human gamma globulin, nor were cross-reactions observed between conjugates prepared with the same hapten, coupled to the same protein, but by two different chemical routes, such that the point of attachment of the hapten to the protein differed. It thus appears that in this system both hapten and carrier protein are necessary, but that neither alone is in general sufficient to stimulate the delayed sensitive cell. Desensitization experiments with cross-reacting hapten-protein conjugates have suggested the presence of a multiplicity of antigenic determinants participating in the elicitation of the delayed lesion, and of a concomitant development of a heterogeneity of specificities in the population of delayed sensitive cells in the sensitized animal. The data are discussed in terms of the apparent requirement of the delayed sensitivity mechanism for a larger functional antigenic determinant than that required for interaction with circulating antibodies. Some possible explanations for this difference, and some of its consequences, are discussed. PMID:13897619

  12. Amacrine cell-mediated input to bipolar cells: variations on a common mechanistic theme.

    PubMed

    Grimes, William N

    2012-01-01

    Feedback is a ubiquitous feature of neural circuits in the mammalian central nervous system (CNS). Analogous to pure electronic circuits, neuronal feedback provides either a positive or negative influence on the output of upstream components/neurons. Although the particulars (i.e., connectivity, physiological encoding/processing/signaling) of circuits in higher areas of the brain are often unclear, the inner retina proves an excellent model for studying both the anatomy and physiology of feedback circuits within the functional context of visual processing. Inner retinal feedback to bipolar cells is almost entirely mediated by a single class of interneurons, the amacrine cells. Although this might sound like a simple circuit arrangement with an equally simple function, anatomical, molecular, and functional evidence suggest that amacrine cells represent an extremely diverse class of CNS interneurons that contribute to a variety of retinal processes. In this review, I classify the amacrine cells according to their anatomical output synapses and target cell(s) (i.e., bipolar cells, ganglion cells, and/or amacrine cells) and discuss specifically our current understandings of amacrine cell-mediated feedback and output to bipolar cells on the synaptic, cellular, and circuit levels, while drawing connections to visual processing.

  13. BNNT-mediated irreversible electroporatio: its potential on cancer cells

    SciTech Connect

    Vittoria Raffa, Cristina Riggio, Michael W. Smith, Kevin C. Jordan, Wei Cao, Alfred Cuschieri

    2012-10-01

    Tissue ablation, i.e., the destruction of undesirable tissues, has become an important minimally invasive technique alternative to resection surgery for the treatment of tumours. Several methods for tissue ablation are based on thermal techniques using cold, e.g. cryosurgery [1] or heat, e.g. radiofrequency [2] or high-intensity focused ultrasound [3] or nanoparticle-mediated irradiation [4]. Alternatively, irreversible electroporation (IRE) has been proposed as non thermal technique for minimally invasive tissue ablation based on the use of electrical pulses. When the electric field is applied to a cell, a change in transmembrane potential is induced, which can cause biochemical and physiological changes of the cell. When the threshold value of the transmembrane potential is exceeded, the cell membrane becomes permeable, thus allowing entrance of molecules that otherwise cannot cross the membrane [5]. A further increase in the electric field intensity may cause irreversible membrane permeabilization and cell death. These pulses create irreversible defects (pores) in the cell membrane lipid bilayer, causing cell death through loss of cell homeostasis [6]. This is desirable in tumour ablation in order to produce large cell death, without the use of cytostatic drugs. A study of Davalos, Mir and Rubinsky showed that IRE can ablate substantial volumes of tissue without inducing a thermal effect and therefore serve as an independent and new tissue ablation modality; this opened the way to the use of IRE in surgery [7]. Their finding was subsequently confirmed in studies on cells [8], small animal models [9] and in large animal models in the liver [10] and the heart [11]. The most important finding in these papers is that irreversible electroporation produces precisely delineated ablation zones with cell scale resolution between ablated and non-ablated areas, without zones in which the extent of damage changes gradually as during thermal ablation. Furthermore, it is

  14. Chemokine-Mediated Migration of Mesencephalic Neural Crest Cells

    PubMed Central

    Rezzoug, Francine; Seelan, Ratnam S.; Bhattacherjee, Vasker; Greene, Robert M.; Pisano, M. Michele

    2011-01-01

    Clefts of the lip and/or palate are among the most prevalent birth defects affecting approximately 7000 newborns in the United States annually. Disruption of the developmentally programmed migration of neural crest cells (NCCs) into the orofacial region is thought to be one of the major causes of orofacial clefting. Signaling of the chemokine SDF-1 (Stromal Derived Factor-1) through its specific receptor, CXCR4, is required for the migration of many stem cell and progenitor cell populations from their respective sites of emergence to the regions where they differentiate into complex cell types, tissues and organs. In the present study, “transwell” assays of chick embryo mesencephalic (cranial) NCC migration and ex ovo whole embryo “bead implantation” assays were utilized to determine whether SDF-1/CXCR4 signaling mediates mesencephalic NCC migration. Results from this study demonstrate that attenuation of SDF-1 signaling, through the use of specific CXCR4 antagonists (AMD3100 and TN14003), disrupts the migration of mesencephalic NCCs into the orofacial region, suggesting a novel role for SDF-1/CXCR4 signaling in the directed migration of mesencephalic NCCs in the early stage embryo. PMID:22015108

  15. Roles of cell signaling pathways in cell-to-cell contact-mediated Epstein-Barr virus transmission.

    PubMed

    Nanbo, Asuka; Terada, Haruna; Kachi, Kunihiro; Takada, Kenzo; Matsuda, Tadashi

    2012-09-01

    Epstein-Barr virus (EBV), a human gamma herpesvirus, establishes a life-long latent infection in B lymphocytes and epithelial cells following primary infection. Several lines of evidence indicate that the efficiency of EBV infection in epithelial cells is accelerated up to 10(4)-fold by coculturing with EBV-infected Burkitt's lymphoma (BL) cells compared to infection with cell-free virions, indicating that EBV infection into epithelial cells is mainly mediated via cell-to-cell contact. However, the molecular mechanisms involved in this pathway are poorly understood. Here, we establish a novel assay to assess cell-to-cell contact-mediated EBV transmission by coculturing an EBV-infected BL cell line with an EBV-negative epithelial cell line under stimulation for lytic cycle induction. By using this assay, we confirmed that EBV was transmitted from BL cells to epithelial cells via cell-to-cell contact but not via cell-to-cell fusion. The inhibitor treatments of extracellular signal-regulated kinase (ERK) and nuclear factor (NF)-κB pathways blocked EBV transmission in addition to lytic induction. The blockage of the phosphoinositide 3-kinase (PI3K) pathway impaired EBV transmission coupled with the inhibition of lytic induction. Knockdown of the RelA/p65 subunit of NF-κB reduced viral transmission. Moreover, these signaling pathways were activated in cocultured BL cells and in epithelial cells. Finally, we observed that viral replication was induced in cocultured BL cells. Taken together, our data suggest that cell-to-cell contact induces multiple cell signaling pathways in BL cells and epithelial cells, contributing to the induction of the viral lytic cycle in BL cells and the enhancement of viral transmission to epithelial cells. PMID:22718812

  16. Fas and its ligand in a general mechanism of T-cell-mediated cytotoxicity.

    PubMed Central

    Hanabuchi, S; Koyanagi, M; Kawasaki, A; Shinohara, N; Matsuzawa, A; Nishimura, Y; Kobayashi, Y; Yonehara, S; Yagita, H; Okumura, K

    1994-01-01

    To investigate the mechanisms of T-cell-mediated cytotoxicity, we estimated the involvement of apoptosis-inducing Fas molecule on the target cells and its ligand on the effector cells. When redirected by ConA or anti-CD3 monoclonal antibody, a CD4+ T-cell clone, BK1, could lyse the target cells expressing wild-type Fas molecule but not those expressing death signaling-deficient mutants. This indicates the involvement of Fas-mediated signal transduction in the target cell lysis by BK1. Anti-CD3-activated but not resting BK1 expressed Fas ligand as detected by binding of a soluble Fas-Ig fusion protein, and the BK1-mediated cytotoxicity was blocked by the addition of Fas-Ig, implicating the inducible Fas ligand in the BK1 cytotoxicity. Ability to exert the Fas-mediated cytotoxicity was not confined to BK1, but splenic CD4+ T cells and, to a lesser extent, CD8+ T cells could also exert the Fas-dependent target cell lysis. This indicates that the Fas-mediated target cell lytic pathway can be generally involved in the T-cell-mediated cytotoxicity. Interestingly, CD4+ T cells prepared from gld/gld mice did not mediate the Fas-mediated cytotoxicity, indicating defective expression of functional Fas ligand in gld mice. PMID:7515183

  17. Molecular basis of sidekick-mediated cell-cell adhesion and specificity

    PubMed Central

    Goodman, Kerry M; Yamagata, Masahito; Jin, Xiangshu; Mannepalli, Seetha; Katsamba, Phinikoula S; Ahlsén, Göran; Sergeeva, Alina P; Honig, Barry; Sanes, Joshua R; Shapiro, Lawrence

    2016-01-01

    Sidekick (Sdk) 1 and 2 are related immunoglobulin superfamily cell adhesion proteins required for appropriate synaptic connections between specific subtypes of retinal neurons. Sdks mediate cell-cell adhesion with homophilic specificity that underlies their neuronal targeting function. Here we report crystal structures of Sdk1 and Sdk2 ectodomain regions, revealing similar homodimers mediated by the four N-terminal immunoglobulin domains (Ig1–4), arranged in a horseshoe conformation. These Ig1–4 horseshoes interact in a novel back-to-back orientation in both homodimers through Ig1:Ig2, Ig1:Ig1 and Ig3:Ig4 interactions. Structure-guided mutagenesis results show that this canonical dimer is required for both Sdk-mediated cell aggregation (via trans interactions) and Sdk clustering in isolated cells (via cis interactions). Sdk1/Sdk2 recognition specificity is encoded across Ig1–4, with Ig1–2 conferring the majority of binding affinity and differential specificity. We suggest that competition between cis and trans interactions provides a novel mechanism to sharpen the specificity of cell-cell interactions. DOI: http://dx.doi.org/10.7554/eLife.19058.001 PMID:27644106

  18. M1 muscarinic receptor activation mediates cell death in M1-HEK293 cells.

    PubMed

    Graham, E Scott; Woo, Kerhan K; Aalderink, Miranda; Fry, Sandie; Greenwood, Jeffrey M; Glass, Michelle; Dragunow, Mike

    2013-01-01

    HEK293 cells have been used extensively to generate stable cell lines to study G protein-coupled receptors, such as muscarinic acetylcholine receptors (mAChRs). The activation of M1 mAChRs in various cell types in vitro has been shown to be protective. To further investigate M1 mAChR-mediated cell survival, we generated stable HEK293 cell-lines expressing the human M1 mAChR. M1 mAChRs were efficiently expressed at the cell surface and efficiently internalised within 1 h by carbachol. Carbachol also induced early signalling cascades similar to previous reports. Thus, ectopically expressed M1 receptors behaved in a similar fashion to the native receptor over short time periods of analysis. However, substantial cell death was observed in HEK293-M1 cells within 24 h after carbachol application. Death was only observed in HEK cells expressing M1 receptors and fully blocked by M1 antagonists. M1 mAChR-stimulation mediated prolonged activation of the MEK-ERK pathway and resulted in prolonged induction of the transcription factor EGR-1 (>24 h). Blockade of ERK signalling with U0126 did not reduce M1 mAChR-mediated cell-death significantly but inhibited the acute induction of EGR-1. We investigated the time-course of cell death using time-lapse microscopy and xCELLigence technology. Both revealed the M1 mAChR cytotoxicity occurs within several hours of M1 activation. The xCELLigence assay also confirmed that the ERK pathway was not involved in cell-death. Interestingly, the MEK blocker did reduce carbachol-mediated cleaved caspase 3 expression in HEK293-M1 cells. The HEK293 cell line is a widely used pharmacological tool for studying G-protein coupled receptors, including mAChRs. Our results highlight the importance of investigating the longer term fate of these cells in short term signalling studies. Identifying how and why activation of the M1 mAChR signals apoptosis in these cells may lead to a better understanding of how mAChRs regulate cell-fate decisions.

  19. Sympathoinhibition and hypotension in carotid sinus hypersensitivity

    NASA Technical Reports Server (NTRS)

    Smith, M. L.; Ellenbogen, K. A.; Eckberg, D. L.

    1992-01-01

    Carotid sinus reflex hypersensitivity is a known cause of syncope in humans. The condition is characterized by cardioinhibition and vasodepression, each to varying degrees. The extent and importance of sympathoinhibition has not been determined in patients with carotid sinus hypersensitivity. This study reports on the extent of sympathoinhibition measured directly directly during carotid massage with and without atrioventricular sequential pacing, in a patient with symptomatic carotid sinus reflex hypersensitivity. Carotid massage elicited asystole, hypotension and complete inhibition of muscle sympathetic nerve activity. Carotid massage during atrioventricular pacing produced similar sympathoinhibition, but with minimal hypotension. Therefore, sympathoinhibition did not contribute importantly to the hypotension during carotid massage in the supine position in this patient. Further investigations are required to elucidate the relation of sympathoinhibition to hypotension in patients with carotid sinus hypersensitivity in the upright position.

  20. Regulation of VH replacement by B cell receptor-mediated signaling in human immature B cells.

    PubMed

    Liu, Jing; Lange, Miles D; Hong, Sang Yong; Xie, Wanqin; Xu, Kerui; Huang, Lin; Yu, Yangsheng; Ehrhardt, Götz R A; Zemlin, Michael; Burrows, Peter D; Su, Kaihong; Carter, Robert H; Zhang, Zhixin

    2013-06-01

    VH replacement provides a unique RAG-mediated recombination mechanism to edit nonfunctional IgH genes or IgH genes encoding self-reactive BCRs and contributes to the diversification of Ab repertoire in the mouse and human. Currently, it is not clear how VH replacement is regulated during early B lineage cell development. In this article, we show that cross-linking BCRs induces VH replacement in human EU12 μHC(+) cells and in the newly emigrated immature B cells purified from peripheral blood of healthy donors or tonsillar samples. BCR signaling-induced VH replacement is dependent on the activation of Syk and Src kinases but is inhibited by CD19 costimulation, presumably through activation of the PI3K pathway. These results show that VH replacement is regulated by BCR-mediated signaling in human immature B cells, which can be modulated by physiological and pharmacological treatments.

  1. Plant Cell Division Analyzed by Transient Agrobacterium-Mediated Transformation of Tobacco BY-2 Cells.

    PubMed

    Buschmann, Henrik

    2016-01-01

    The continuing analysis of plant cell division will require additional protein localization studies. This is greatly aided by GFP-technology, but plant transformation and the maintenance of transgenic lines can present a significant technical bottleneck. In this chapter I describe a method for the Agrobacterium-mediated genetic transformation of tobacco BY-2 cells. The method allows for the microscopic analysis of fluorescence-tagged proteins in dividing cells in within 2 days after starting a coculture. This transient transformation procedure requires only standard laboratory equipment. It is hoped that this rapid method would aid researchers conducting live-cell localization studies in plant mitosis and cytokinesis.

  2. Autophagy as a Survival Mechanism for Squamous Cell Carcinoma Cells in Endonuclease G-Mediated Apoptosis

    PubMed Central

    Masui, Atsushi; Hamada, Masakazu; Kameyama, Hiroyasu; Wakabayashi, Ken; Takasu, Ayako; Imai, Tomoaki; Iwai, Soichi; Yura, Yoshiaki

    2016-01-01

    Safingol, L- threo-dihydrosphingosine, induces cell death in human oral squamous cell carcinoma (SCC) cells through an endonuclease G (endoG) -mediated pathway. We herein determined whether safingol induced apoptosis and autophagy in oral SCC cells. Safingol induced apoptotic cell death in oral SCC cells in a dose-dependent manner. In safingol-treated cells, microtubule-associated protein 1 light chain 3 (LC3)-I was changed to LC3-II and the cytoplasmic expression of LC3, amount of acidic vesicular organelles (AVOs) stained by acridine orange and autophagic vacuoles were increased, indicating the occurrence of autophagy. An inhibitor of autophagy, 3-methyladenine (3-MA), enhanced the suppressive effects of safingol on cell viability, and this was accompanied by an increase in the number of apoptotic cells and extent of nuclear fragmentation. The nuclear translocation of endoG was minimal at a low concentration of safingol, but markedly increased when combined with 3-MA. The suppressive effects of safingol and 3-MA on cell viability were reduced in endoG siRNA- transfected cells. The scavenging of reactive oxygen species (ROS) prevented cell death induced by the combinational treatment, whereas a pretreatment with a pan-caspase inhibitor z-VAD-fmk did not. These results indicated that safingol induced apoptosis and autophagy in SCC cells and that the suppression of autophagy by 3-MA enhanced apoptosis. Autophagy supports cell survival, but not cell death in the SCC cell system in which apoptosis occurs in an endoG-mediated manner. PMID:27658240

  3. Food hypersensitivity to lamb in a cat.

    PubMed

    Reedy, L M

    1994-04-01

    Severe facial pruritus in a cat was caused by food hypersensitivity to lamb. The cat had been fed an exclusive diet of lamb for 2 years after it had been diagnosed to have food hypersensitivity to fish. Signs, including erythema, alopecia, and excoriations of the head and neck, were poorly responsive to corticosteroid administration, but resolved within a few weeks after removal of the suspected allergen.

  4. Drug-Hypersensitivity Syndrome: Diagnosis and Treatment

    PubMed Central

    Hamm, Rose L.

    2012-01-01

    Drug-induced hypersensitivity syndrome is a systemic autoimmune disorder that results in mucocutaneous symptoms ranging in severity from mild pruritus to life-threatening skin and mucosal loss, with different nomenclature depending on the severity of the symptoms. The purpose of this article is to review the recent advances in understanding the pathology of drug-induced hypersensitivity syndrome, as well as current recommendations for both medical and wound management. PMID:24527369

  5. Mast Cells in Allergic Diseases and Mastocytosis

    PubMed Central

    Marquardt, Diana L.; Wasserman, Stephen I.

    1982-01-01

    Mast cells with their stores of vasoactive and chemotactic mediators are central to the pathogenesis of allergic diseases. The cross-linking of receptorbound IgE molecules on the surface of mast cells initiates a complex chain of events, including calcium ion influx, phospholipid methylation and turnover and cyclic nucleotide metabolism, ultimately resulting in the release of mediators of immediate hypersensitivity. These mast cell mediators are important in smooth muscle reactivity, in the recruitment of eosinophilic and neutrophilic leukocytes and in the generation of secondary chemical mediators. Histologic evidence of mast cell degranulation, biochemical evidence of mast cell mediators in blood and tissues and clinical evidence of signs and symptoms reproducible by these mediators have strongly supported the crucial role of mast cells in asthma, urticaria, anaphylaxis, rhinitis and mastocytosis. Because of their unique location at host environment interfaces, mast cells may both participate in allergic diseases and promote homeostasis. ImagesFigure 1.Figure 2.Figure 3. PMID:6293204

  6. Recent advances in hypersensitivity pneumonitis.

    PubMed

    Lacasse, Yves; Girard, Mélissa; Cormier, Yvon

    2012-07-01

    Hypersensitivity pneumonitis (HP) is a pulmonary disease with symptoms of dyspnea and cough resulting from the inhalation of an allergen to which the subject has been previously sensitized. The diagnosis of HP most often relies on an array of nonspecific clinical symptoms and signs developed in an appropriate setting, with the demonstration of interstitial markings on chest radiographs, serum precipitating antibodies against offending antigens, a lymphocytic alveolitis on BAL, and/or a granulomatous reaction on lung biopsies. The current classification of HP in acute, subacute, and chronic phases is now challenged, and a set of clinical predictors has been proposed. Nonspecific interstitial pneumonitis, usual interstitial pneumonia, and bronchiolitis obliterans organizing pneumonia may be the sole histologic expression of the disease. Presumably, like in idiopathic interstitial pneumonia, acute exacerbations of chronic HP may occur without further exposure to the offending antigen. New offending antigens, such as mycobacteria causing hot tub lung and metalworking fluid HP, have recently been identified and have stimulated further research in HP. PMID:22796841

  7. Effect of Lactobacillus paracasei NCC2461 on antigen-specific T-cell mediated immune responses in aged mice.

    PubMed

    Vidal, Karine; Benyacoub, Jalil; Moser, Mireille; Sanchez-Garcia, J; Serrant, Patrick; Segura-Roggero, Iris; Reuteler, Gloria; Blum, Stephanie

    2008-10-01

    Aging is associated with a reduced capacity to mount proper immune responses, in particular to vaccines. Probiotic lactic acid bacteria may improve the immune status of the elderly; however, there is little evidence showing an effect of these bacteria on humoral and cellular immune responses. In the present study, the immunomodulatory capacity of the probiotic Lactobacillus paracasei NCC2461 combined or not with a prebiotic composition, FOS/inulin, was examined in aged mice. Male C57BL/6J mice (21-months-old) were allocated to one of three groups fed ad libitum for 44 days with different diets: a normal diet (control), a normal diet plus NCC2461 given in the drinking water, or a diet containing FOS/inulin plus NCC2461 in the drinking water. All mice were immunized on day 15 and challenged on day 22 with keyhole limpet hemocyanin (KLH). T helper (Th)1 cell-dependent immune responses (anti-KLH immunoglobulin G(2a) [IgG(2a)] levels and delayed type hypersensitivity response) were increased significantly in NCC2461-supplemented mice when compared to controls. Supplementation with FOS/inulin did not further improve the immune-enhancing effect mediated by the probiotic. Splenocyte proliferation, T cell subsets, systemic total IgG levels, and mucosal total IgA responses were not affected. Interestingly, supplementation with NCC2461 modulated the intestinal microbiota composition by increasing the numbers of bifidobacteria and lactobacilli. In conclusion, oral intake of L. paracasei NCC2461 by aged mice enhanced the specific adaptive immune response to in vivo antigenic challenge without altering other cellular and humoral immune responses. The poor responsiveness to antigenic challenge, frequently observed in elderly people, may be improved by supplementation with L. paracasei NCC2461. PMID:18922048

  8. EXPRESS: Histone hyperacetylation modulates spinal type II metabotropic glutamate receptor alleviating stress-induced visceral hypersensitivity in female rats.

    PubMed

    Cao, Dong-Yuan; Bai, Guang; Ji, Yaping; Karpowicz, Jane M; Traub, Richard J

    2016-01-01

    Stress is often a trigger to exacerbate chronic pain including visceral hypersensitivity associated with irritable bowel syndrome, a female predominant functional bowel disorder. Epigenetic mechanisms that mediate stress responses are a potential target to interfere with visceral pain. The purpose of this study was to examine the effect of a histone deacetylase inhibitor, suberoylanilide hydroxamic acid, on visceral hypersensitivity induced by a subchronic stressor in female rats and to investigate the involvement of spinal glutamate receptors. Three daily sessions of forced swim induced visceral hypersensitivity. Intrathecal suberoylanilide hydroxamic acid prevented or reversed the stress-induced visceral hypersensitivity, increased spinal histone 3 acetylation and increased mGluR2 and mGluR3 expression. Chromatin immunoprecipitation (ChIP) analysis revealed enrichment of H3K9Ac and H3K18Ac at several promoter Grm2 and Grm3 regions. The mGluR2/3 antagonist LY341495 reversed the inhibitory effect of suberoylanilide hydroxamic acid on the stress-induced visceral hypersensitivity. In surprising contrast, stress and/or suberoylanilide hydroxamic acid had no effect on spinal NMDA receptor expression or function. These data reveal histone modification modulates mGluR2/3 expression in the spinal cord to attenuate stressinduced visceral hypersensitivity. HDAC inhibitors may provide a potential approach to relieve visceral hypersensitivity associated with irritable bowel syndrome. PMID:27385724

  9. Histone hyperacetylation modulates spinal type II metabotropic glutamate receptor alleviating stress-induced visceral hypersensitivity in female rats

    PubMed Central

    Cao, Dong-Yuan; Bai, Guang; Ji, Yaping; Karpowicz, Jane

    2016-01-01

    Stress is often a trigger to exacerbate chronic pain including visceral hypersensitivity associated with irritable bowel syndrome, a female predominant functional bowel disorder. Epigenetic mechanisms that mediate stress responses are a potential target to interfere with visceral pain. The purpose of this study was to examine the effect of a histone deacetylase inhibitor, suberoylanilide hydroxamic acid, on visceral hypersensitivity induced by a subchronic stressor in female rats and to investigate the involvement of spinal glutamate receptors. Three daily sessions of forced swim induced visceral hypersensitivity. Intrathecal suberoylanilide hydroxamic acid prevented or reversed the stress-induced visceral hypersensitivity, increased spinal histone 3 acetylation and increased mGluR2 and mGluR3 expression. Chromatin immunoprecipitation (ChIP) analysis revealed enrichment of H3K9Ac and H3K18Ac at several promoter Grm2 and Grm3 regions. The mGluR2/3 antagonist LY341495 reversed the inhibitory effect of suberoylanilide hydroxamic acid on the stress-induced visceral hypersensitivity. In surprising contrast, stress and/or suberoylanilide hydroxamic acid had no effect on spinal NMDA receptor expression or function. These data reveal histone modification modulates mGluR2/3 expression in the spinal cord to attenuate stress-induced visceral hypersensitivity. HDAC inhibitors may provide a potential approach to relieve visceral hypersensitivity associated with irritable bowel syndrome. PMID:27385724

  10. Depletion-mediated red blood cell aggregation in polymer solutions.

    PubMed

    Neu, Björn; Meiselman, Herbert J

    2002-11-01

    Polymer-induced red blood cell (RBC) aggregation is of current basic science and clinical interest, and a depletion-mediated model for this phenomenon has been suggested; to date, however, analytical approaches to this model are lacking. An approach is thus described for calculating the interaction energy between RBC in polymer solutions. The model combines electrostatic repulsion due to RBC surface charge with osmotic attractive forces due to polymer depletion near the RBC surface. The effects of polymer concentration and polymer physicochemical properties on depletion layer thickness and on polymer penetration into the RBC glycocalyx are considered for 40 to 500 kDa dextran and for 18 to 35 kDa poly (ethylene glycol). The calculated results are in excellent agreement with literature data for cell-cell affinities and with RBC aggregation-polymer concentration relations. These findings thus lend strong support to depletion interactions as the basis for polymer-induced RBC aggregation and suggest the usefulness of this approach for exploring interactions between macromolecules and the RBC glycocalyx. PMID:12414682

  11. Autophagy mediates phase transitions from cell death to life.

    PubMed

    Han, Kyungreem; Kim, Jinwoong; Choi, MooYoung

    2015-09-01

    Autophagy is a lysosomal degradation pathway, which is critical for maintaining normal cellular functions. Despite considerable advances in defining the specific molecular mechanism governing the autophagy pathway during the last decades, we are still far from understanding the underlying principle of the autophagy machinery and its complex role in human disease. As an alternative attempt to reinvigorate the search for the principle of the autophagy pathway, we in this study make use of the computer-aided analysis, complementing current molecular-level studies of autophagy. Specifically, we propose a hypothesis that autophagy mediates cellular phase transitions and demonstrate that the autophagic phase transitions are essential to the maintenance of normal cellular functions and critical in the fate of a cell, i.e., cell death or survival. This study should provide valuable insight into how interactions of sub-cellular components such as genes and protein modules/complexes regulate autophagy and then impact on the dynamic behaviors of living cells as a whole, bridging the microscopic molecular-level studies and the macroscopic cellular-level and physiological approaches. PMID:27441218

  12. Interleukin-22 Promotes Intestinal Stem Cell-Mediated Epithelial Regeneration

    PubMed Central

    Dudakov, Jarrod A.; Jenq, Robert R.; Velardi, Enrico; Young, Lauren F.; Smith, Odette M.; Lawrence, Gillian; Ivanov, Juliet A.; Fu, Ya-Yuan; Takashima, Shuichiro; Hua, Guoqiang; Martin, Maria L.; O'Rourke, Kevin P.; Lo, Yuan-Hung; Mokry, Michal; Romera-Hernandez, Monica; Cupedo, Tom; Dow, Lukas; Nieuwenhuis, Edward E.; Shroyer, Noah F.; Liu, Chen; Kolesnick, Richard

    2015-01-01

    Epithelial regeneration is critical for barrier maintenance and organ function after intestinal injury. The intestinal stem cell (ISC) niche provides Wnt, Notch, and epidermal growth factor (EGF) signals supporting Lgr5+ crypt base columnar ISCs for normal epithelial maintenance1,2. However, little is known about the regulation of the ISC compartment after tissue damage. Utilizing ex vivo organoid cultures, we provide evidence that innate lymphoid cells (ILCs), potent producers of Interleukin-22 (IL-22) after intestinal injury3,4, increased the growth of murine small intestine (SI) organoids in an IL-22-dependent fashion. Recombinant IL-22 directly targeted ISCs, augmenting the growth of both murine and human intestinal organoids, increasing proliferation, and promoting ISC expansion. IL-22 induced Stat3 phosphorylation in Lgr5+ ISCs, and Stat3 was critical for both organoid formation and IL-22-mediated regeneration. Treatment with IL-22 in vivo after murine allogeneic bone marrow transplantation (BMT) enhanced recovery of ISCs, increased epithelial regeneration, and reduced intestinal pathology and mortality from graft vs. host disease (GVHD). Atoh1-deficient organoid culture demonstrated that IL-22 induced epithelial regeneration independent of the Paneth cell niche. Our findings reveal a fundamental mechanism by which the immune system is able to support intestinal epithelium, activating ISCs to promote regeneration. PMID:26649819

  13. Ca-Mediated Electroformation of Cell-Sized Lipid Vesicles

    PubMed Central

    Tao, Fei; Yang, Peng

    2015-01-01

    Cell-sized lipid giant unilamellar vesicles (GUVs) are formed when lipid molecules self-assemble to construct a single bilayer compartment with similar morphology to living cells. The physics of self-assembly process is only generally understood and the size distribution of GUVs tends to be very polydisperse. Herein we report a strategy for the production of controlled size distributions of GUVs by a novel mechanism dissecting the mediation ability of calcium (Ca) on the conventional electroformation of GUVs. We finely construct both of the calcium ion (Ca2+) and calcium carbonate (CaCO3) mineral adsorption layers on a lipid film surface respectively during the electroformation of GUVs. It is found that Ca2+ Slip plane polarized by alternating electric field could induce a pattern of electroosmotic flow across the surface, and thus confine the fusion and growth of GUVs to facilitate the formation of uniform GUVs. The model is further improved by directly using CaCO3 that is in situ formed on a lipid film surface, providing a GUV population with narrow polydispersity. The two models deciphers the new biological function of calcium on the birth of cell-like lipid vesicles, and thus might be potentially relevant to the construction of new model to elucidate the cellular development process. PMID:25950604

  14. Depressed cell-mediated immunity in coeliac disease.

    PubMed Central

    Scott, B B; Losowsky, M S

    1976-01-01

    Fourteen coeliac patients on a gluten free diet (GFD) and 10 on a normal diet were studied by lymphocyte transformation in response to PHA to assess the integrity of cell-mediated immunity (CMI). Transformation was depressed in the majority taking a normal diet, with improvement after a GFD. In some patients the depression may have been due to a serum factor, as transformation was more nearly normal when the lymphocytes were cultured in pooled AB serum than in their own serum. There was no correlation between transformation and nutritional deficiencies. Mantoux tests were performed in some of these and other coeliac patients and there was a very significant reduction in the incidence of positive tests compared with controls. These findings provide evidence of depressed CMI in coeliac patients taking a normal diet with improvement on a GFD and may be of relevance to the high risk of malignancy in coeliac disease, further strengthening the case for a strict GFD. PMID:1087262

  15. Adenovirus-mediated gene transfer to tumor cells.

    PubMed

    Cascalló, Manel; Alemany, Ramon

    2004-01-01

    Cell transduction in vitro is only the first step toward proving that a genetherapy vector can be useful to treat tumors. However, tumor targeting in vivo is now the milestone for gene therapy to succeed against disseminated cancer. Therefore, most valuable information is obtained from studies of vector biodistribution. Owing to the hepatotropism of adenoviral vectors, a particularly important parameter is the tumor/liver ratio. This ratio can be given at the level of gene expression if the amount of transgene expression is measured. To optimize the targeting, however, the levels of viral particles that reach the tumor compared to other organs must be studied. Most of this chapter deals with methods to quantify the virus fate in tumor-bearing animals. We present a radioactive labeling method that can be used to study biodistribution. After a small section dealing with tumor models, we describe methods to quantify different parameters related to adenovirus-mediated tumor targeting. PMID:14970588

  16. Cell mediated immunity in Antarctic wintering personnel; 1984-1992.

    PubMed

    Muller, H K; Lugg, D J; Quinn, D

    1995-08-01

    Cell-mediated immune responses were studied in 12 Antarctic and sub-Antarctic wintering groups at quarterly intervals over the period 1984-1992, using the cutaneous CMI Multitest. These populations are among the most isolated on earth. While the sub-Antarctic population at Macquarie Island had levels of responsiveness and hypoergy (9%) comparable to healthy populations in temperate zones, the Antarctic Continental group showed a level of hypoergy of 36%. There was no seasonal variation in the pattern of responses. It is concluded that the extreme and isolated environment and stress factors are responsible for the decreased immunological responsiveness but the mechanisms are presently unclear. On review, one factor appears to be perceived anxiety. The high rate of hypoergy in Antarctica, where medical care is limited, may have health implications. These groups provide an excellent analogue for immunological investigations in longer term space flight.

  17. Hypoxia-mediated regulation of gene expression in mammalian cells

    PubMed Central

    Shih, Shu-Ching; Claffey, Kevin P.

    1998-01-01

    The molecular mechanism underlying oxygen sensing in mammalian cells has been extensively investigated in the areas of glucose transport, glycolysis, erythropoiesis, angiogenesis and catecholamine metabolism. Expression of functionally operative representative proteins in these specific areas, such as the glucose transporter 1, glycolytic enzymes, erythropoietin, vascular endothelial growth factor and tyrosine hydroxylase are all induced by hypoxia. Recent studies demonstrated that both transcriptional activation and post-transcriptional mechanisms are important to the hypoxia-mediated regulation of gene expression. In this article, the cis-acting elements and trans-acting factors involved in the transcriptional activation of gene expression will be reviewed. In addition, the mechanisms of post-transcriptional mRNA stabilization will also be addressed. We will discuss whether these two processes of regulation of hypoxia-responsive genes are mechanistically linked and co-operative in nature. PMID:10319016

  18. RECQL4-deficient cells are hypersensitive to oxidative stress/damage: Insights for osteosarcoma prevalence and heterogeneity in Rothmund-Thomson syndrome

    SciTech Connect

    Werner, Sean R.; Prahalad, Agasanur K. . E-mail: aprahala@iupui.edu; Yang Jieping; Hock, Janet M.

    2006-06-23

    Rothmund-Thomson syndrome (RTS) is a heterogeneous disease, associated with increased prevalence of osteosarcoma in very young patients with a mutated RECQL4 gene. In this study, we tested the ability of RECQL4 deficient fibroblasts, derived from a RTS patient to recover from hydrogen peroxide (H{sub 2}O{sub 2})-induced oxidative stress/damage. Immunoperoxidase staining for 8-oxo-deoxyguanosine (8-oxo-dG) formation in RTS and normal human fibroblasts were compared to assess DNA damage. We determined DNA synthesis, cell growth, cell cycle distribution, and viability in RTS and normal human fibroblasts before and after H{sub 2}O{sub 2} treatment. H{sub 2}O{sub 2} induces 8-oxo-dG formation in both RTS and normal fibroblasts. In normal human fibroblasts, RECQL4 was predominantly localized to cytoplasm; nuclear translocation and foci formation occurred in response to oxidant stimulation. After recovery from oxidant exposure, viable RTS fibroblasts showed irreversible growth arrest compared to normal fibroblasts. DNA synthesis decreased significantly in treated RTS cells, with concomitant reduction of cells in the S-phase. These results suggest that enhanced oxidant sensitivity in RECQL4 deficient fibroblasts derived from RTS patients could be attributed to abnormal DNA metabolism and proliferation failure. The ramifications of these findings on osteosarcoma prevalence and heterogeneity in RTS are discussed.

  19. In vivo protein binding sites and nuclease hypersensitivity in the promoter region of a cell cycle regulated human H3 histone gene.

    PubMed Central

    Pauli, U; Chrysogelos, S; Nick, H; Stein, G; Stein, J

    1989-01-01

    The chromatin structure and protein-DNA interactions of a cell cycle regulated human H3 histone gene have been examined at different levels of resolution. Using traditional Southern blot analysis we have investigated the accessibility of the H3 coding region and its flanking sequences to DNase I, S1 nuclease and restriction endonuclease digestion. Using the native genomic blotting method recently developed in our laboratory, two sites of protein-DNA interaction in the proximal 240 bp of the promoter region of this H3 gene were established. Further in vivo analysis of protein-DNA binding sites in intact cells by genomic sequencing revealed, with single nucleotide resolution, the guanine contacts and footprints of the proteins bound to the promoter. The relative locations of protein-DNA interactions in this H3 gene are similar to those identified in vivo and in vitro in a cell cycle dependent human H4 histone gene. The proteins complexed with the H3 histone gene promoter can be dissociated between 0.16 and 0.28 M NaCl. The protein-DNA contacts persist throughout the cell cycle and thus may have a functional relationship with the basal level of transcription of this H3 gene that occurs during and outside of S phase. Images PMID:2539585

  20. The alternative complement component factor B regulates UV-induced oedema, systemic suppression of contact and delayed hypersensitivity, and mast cell infiltration into the skin.

    PubMed

    Byrne, Scott N; Hammond, Kirsten J L; Chan, Carling Y-Y; Rogers, Linda J; Beaugie, Clare; Rana, Sabita; Marsh-Wakefield, Felix; Thurman, Joshua M; Halliday, Gary M

    2015-04-01

    Ultraviolet (UV) wavelengths in sunlight are the prime cause of skin cancer in humans with both the UVA and UVB wavebands making a contribution to photocarcinogenesis. UV has many different biological effects on the skin that contribute to carcinogenesis, including suppression of adaptive immunity, sunburn and altering the migration of mast cells into and away from irradiated skin. Many molecular mechanisms have been identified as contributing to skin responses to UV. Recently, using gene set enrichment analysis of microarray data, we identified the alternative complement pathway with a central role for factor B (fB) in UVA-induced immunosuppression. In the current study we used mice genetically deficient in fB (fB-/- mice) to study the functional role of the alternative complement pathway in skin responses to UV. We found that fB is required for not only UVA but also UVB-induced immunosuppression and solar-simulated UV induction of the oedemal component of sunburn. Factor B-/- mice had a larger number of resident skin mast cells than control mice, but unlike the controls did not respond to UV by increasing mast cell infiltration into the skin. This study provides evidence for a function role for fB in skin responses to UV radiation. Factor B regulates UVA and UVB induced immunosuppression, UV induced oedema and mast cell infiltration into the skin. The alternative complement pathway is therefore an important regulator of skin responses to UV.

  1. Altered heme-mediated modulation of dendritic cell function in sickle cell alloimmunization

    PubMed Central

    Godefroy, Emmanuelle; Liu, Yunfeng; Shi, Patricia; Mitchell, W. Beau; Cohen, Devin; Chou, Stella T.; Manwani, Deepa; Yazdanbakhsh, Karina

    2016-01-01

    Transfusions are the main treatment for patients with sickle cell disease. However, alloimmunization remains a major life-threatening complication for these patients, but the mechanism underlying pathogenesis of alloimmunization is not known. Given the chronic hemolytic state characteristic of sickle cell disease, resulting in release of free heme and activation of inflammatory cascades, we tested the hypothesis that anti-inflammatory response to heme is compromised in alloimmunized sickle patients, increasing their risk of alloimmunization. Heme-exposed monocyte-derived dendritic cells from both non-alloimmunized sickle patients and healthy donors inhibited priming of pro-inflammatory CD4+ type 1 T cells, and exhibited significantly reduced levels of the maturation marker CD83. In contrast, in alloimmunized patients, heme did not reverse priming of pro-inflammatory CD4+ cells by monocyte-derived dendritic cells or their maturation. Furthermore, heme dampened NF-κB activation in non-alloimmunized, but not in alloimmunized monocyte-derived dendritic cells. Heme-mediated CD83 inhibition depended on Toll-like receptor 4 but not heme oxygenase 1. These data suggest that extracellular heme limits CD83 expression on dendritic cells in non-alloimmunized sickle patients through a Toll-like receptor 4-mediated pathway, involving NF-κB, resulting in dampening of pro-inflammatory responses, but that in alloimmunized patients this pathway is defective. This opens up the possibility of developing new therapeutic strategies to prevent sickle cell alloimmunization. PMID:27229712

  2. Altered heme-mediated modulation of dendritic cell function in sickle cell alloimmunization.

    PubMed

    Godefroy, Emmanuelle; Liu, Yunfeng; Shi, Patricia; Mitchell, W Beau; Cohen, Devin; Chou, Stella T; Manwani, Deepa; Yazdanbakhsh, Karina

    2016-09-01

    Transfusions are the main treatment for patients with sickle cell disease. However, alloimmunization remains a major life-threatening complication for these patients, but the mechanism underlying pathogenesis of alloimmunization is not known. Given the chronic hemolytic state characteristic of sickle cell disease, resulting in release of free heme and activation of inflammatory cascades, we tested the hypothesis that anti-inflammatory response to heme is compromised in alloimmunized sickle patients, increasing their risk of alloimmunization. Heme-exposed monocyte-derived dendritic cells from both non-alloimmunized sickle patients and healthy donors inhibited priming of pro-inflammatory CD4(+) type 1 T cells, and exhibited significantly reduced levels of the maturation marker CD83. In contrast, in alloimmunized patients, heme did not reverse priming of pro-inflammatory CD4(+) cells by monocyte-derived dendritic cells or their maturation. Furthermore, heme dampened NF-κB activation in non-alloimmunized, but not in alloimmunized monocyte-derived dendritic cells. Heme-mediated CD83 inhibition depended on Toll-like receptor 4 but not heme oxygenase 1. These data suggest that extracellular heme limits CD83 expression on dendritic cells in non-alloimmunized sickle patients through a Toll-like receptor 4-mediated pathway, involving NF-κB, resulting in dampening of pro-inflammatory responses, but that in alloimmunized patients this pathway is defective. This opens up the possibility of developing new therapeutic strategies to prevent sickle cell alloimmunization.

  3. Enhanced in vitro phagocytic power of macrophages from PPD-stimulated skin sites in human subjects hypersensitive to PPD

    PubMed Central

    Magliulo, E.; De Feo, V.; Stirpe, A.; Riva, C.; Scevola, D.

    1973-01-01

    By a quantitative Rebuck's skin-window technique human macrophages were collected from individuals either unreactive or hypersensitive to PPD, the latter having recovered from tuberculous infection. In vitro testing of macrophages with a strain of Paracolonbacter aerogenoides proved that cells from hypersensitive convalescents were provided with increased pagocytic and bactericidal activities. An even higher degree of macrophage activation was attained when cells from hypersensitive individuals had previously been stimulated in vitro with PPD. Changes of macrophage functions such as those mentioned above might well result from the action on macrophages of lympho-kine-like agents released by sensitized lymphocytes coming in contact with PPD. PMID:4579779

  4. Tie-mediated signal from apoptotic cells protects stem cells in Drosophila melanogaster.

    PubMed

    Xing, Yalan; Su, Tin Tin; Ruohola-Baker, Hannele

    2015-01-01

    Many types of normal and cancer stem cells are resistant to killing by genotoxins, but the mechanism for this resistance is poorly understood. Here we show that adult stem cells in Drosophila melanogaster germline and midgut are resistant to ionizing radiation (IR) or chemically induced apoptosis and dissect the mechanism for this protection. We find that upon IR the receptor tyrosine kinase Tie/Tie-2 is activated, leading to the upregulation of microRNA bantam that represses FOXO-mediated transcription of pro-apoptotic Smac/DIABLO orthologue, Hid in germline stem cells. Knockdown of the IR-induced putative Tie ligand, Pvf1, a functional homologue of human Angiopoietin, in differentiating daughter cells renders germline stem cells sensitive to IR, suggesting that the dying daughters send a survival signal to protect their stem cells for future repopulation of the tissue. If conserved in cancer stem cells, this mechanism may provide therapeutic options for the eradication of cancer. PMID:25959206

  5. Protective effect of thioredoxin upon NO-mediated cell injury in THP1 monocytic human cells.

    PubMed Central

    Ferret, P J; Soum, E; Negre, O; Wollman, E E; Fradelizi, D

    2000-01-01

    Although NO has been postulated to play important roles in host defences, it is potentially damaging for exposed cells, including for the macrophages producing the NO. Thus a network of radical acceptors and enzymes is thought to play an important redox-buffering role to protect cells against NO-mediated injury. We examined the properties of the redox systems superoxide dismutase (SOD)/catalase, glutathione (GSH) and thioredoxin (Trx), in regulating the viability of two human monocytic cell lines (THP1 and U937) exposed to the NO-generating compound diethylene triamine-nitric oxide (DETA-NO). We observed that NO-induced cytotoxic effects were time- and dose-dependent towards the two cell lines. After vitamin-induced differentiation in vitro with retinoic acid (RA) and 1,25-dihydroxy vitamin D(3) (VD), termed RA/VD, we observed that THP1 RA/VD cells became more resistant to NO-mediated cytotoxicity whereas the susceptibility of U937 cells was not modified. Using Western blotting and reverse-transcriptase PCR methods, we observed that gene transcription and protein expression of Trx and thioredoxin reductase were significantly increased upon RA/VD treatment and differentiation in THP1 cells. By contrast, SOD/catalase and GSH redox state remained unmodified. Finally, a stable transfectant THP1 line overexpressing Trx was found to be more resistant than THP1 control cells that were untransfected or transfected with an empty plasmid, when exposed to DETA-NO in vitro. In conclusion, we observed an inverse correlation between cell susceptibility to NO damaging effects and Trx expression, suggesting that the Trx system may have important preventative capacities towards NO-mediated cellular injury in monocytic macrophage cells. PMID:10698704

  6. Langerhans Cells Suppress CD49a+ NK Cell-Mediated Skin Inflammation.

    PubMed

    Scholz, Felix; Naik, Shruti; Sutterwala, Fayyaz S; Kaplan, Daniel H

    2015-09-01

    Recruitment of innate immune effector cells into sites of infection is a critical component of resistance to pathogen infection. Using a model of intradermal footpad injection of Candida albicans, we observed that inflammation as measured by footpad thickness and neutrophil recruitment occurred independent of adoptive immunity but was significantly reduced in MyD88(-/-) and IL-6(-/-) mice. Unexpectedly, huLangerin-DTA mice (ΔLC) that lack Langerhans cells (LC) developed increased skin inflammation and expressed higher amounts of IL-6, suggesting a suppressive role for LC. Increased inflammation also occurred in Rag1(-/-) ΔLC mice but was reversed by Ab-mediated ablation of NK cells. CXCR6(+)CD49a(+) NK cells are a liver-resident subset that can mediate inflammatory skin responses. We found that exaggerated skin inflammation was absent in ΔLC × CXCR6(-/-) mice. Moreover, the exaggerated response in ΔLC mice could be adoptively transferred with liver CD49a(+) NK cells. Finally, CD49a(+) NK cells in ΔLC but not control mice were recruited to the skin, and inhibition of their recruitment prevented the exaggerated response. Thus, in the absence of LC, CD49a(+) liver NK cells display an inappropriately proinflammatory phenotype that results in increased local skin inflammation. These data reveal a novel function for LC in the regulation of this recently described subset of skin tropic NK cells. PMID:26209621

  7. Visfatin Mediates SCLC Cells Migration across Brain Endothelial Cells through Upregulation of CCL2.

    PubMed

    Liu, Tingting; Miao, Ziwei; Jiang, Jiusheng; Yuan, Shuai; Fang, Wengang; Li, Bo; Chen, Yuhua

    2015-05-18

    Small-cell lung cancer (SCLC) is characterized as an aggressive tumor with brain metastasis. Although preventing SCLC metastasis to the brain is immensely important for survival, the molecular mechanisms of SCLC cells penetrating the blood-brain barrier (BBB) are largely unknown. Recently, visfatin has been considered as a novel pro-inflammatory adipocytokine involved in various cancers. Herein, we present evidence that elevated levels of visfatin in the serum of SCLC patients were associated with brain metastasis, and visfain was increased in NCI-H446 cells, a SCLC cell line, during interacting with human brain microvascular endothelial cells (HBMEC). Using in vitro BBB model, we found that visfatin could promote NCI-H446 cells migration across HBMEC monolayer, while the effect was inhibited by knockdown of visfatin. Furthermore, our findings indicated that CC chemokine ligand 2 (CCL2) was involved in visfatin-mediated NCI-H446 cells transendothelial migtation. Results also showed that the upregulation of CCL2 in the co-culture system was reversed by blockade of visfatin. In particular, visfatin-induced CCL2 was attenuated by specific inhibitor of PI3K/Akt signaling in NCI-H446 cells. Taken together, we demonstrated that visfatin was a prospective target for SCLC metastasis to brain, and understanding the molecular mediators would lead to effective strategies for inhibition of SCLC brain metastasis.

  8. Retrovirus-mediated conditional immortalization and analysis of established cell lines of osteoclast precursor cells

    SciTech Connect

    Kawata, Shigehisa; Suzuki, Jun; Maruoka, Masahiro; Mizutamari, Megumi; Ishida-Kitagawa, Norihiro; Yogo, Keiichiro; Jat, Parmjit S.; Shishido, Tomoyuki . E-mail: shishid@bs.naist.jp

    2006-11-10

    Osteoclast precursor cells (OPCs) have previously been established from bone marrow cells of SV40 temperature-sensitive T antigen-expressing transgenic mice. Here, we use retrovirus-mediated gene transfer to conditionally immortalize OPCs by expressing temperature-sensitive large T antigen (tsLT) from wild type bone marrow cells. The immortalized OPCs proliferated at the permissive temperature of 33.5 deg. C, but stopped growing at the non-permissive temperature of 39 deg. C. In the presence of receptor activator of NF{kappa}B ligand (RANKL), the OPCs differentiated into tartrate-resistant acid phosphatase (TRAP)-positive cells and formed multinucleate osteoclasts at 33.5 deg. C. From these OPCs, we cloned two types of cell lines. Both differentiated into TRAP-positive cells, but one formed multinucleate osteoclasts while the other remained unfused in the presence of RANKL. These results indicate that the established cell lines are useful for analyzing mechanisms of differentiation, particularly multinucleate osteoclast formation. Retrovirus-mediated conditional immortalization should be a useful method to immortalize OPCs from primary bone marrow cells.

  9. The lectin ArtinM binds to mast cells inducing cell activation and mediator release.

    PubMed

    Barbosa-Lorenzi, Valéria Cintra; Buranello, Patrícia Andressa de Almeida; Roque-Barreira, Maria Cristina; Jamur, Maria Célia; Oliver, Constance; Pereira-da-Silva, Gabriela

    2011-12-16

    Mast cells are inflammatory cells that respond to signals of innate and adaptive immunity with immediate and delayed release of mediators. ArtinM, a lectin from Artocarpus integrifolia with immunomodulatory activities, is able to induce mast cell activation, but the mechanisms remain unknown. This study sought to further investigate the effects of the lectin on mast cells. We showed that ArtinM binds to mast cells, possibly to the high affinity receptor for immunoglobulin E (IgE) - FcεRI - and/or to IgE bound to FcεRI. Binding of the lectin resulted in protein tyrosine phosphorylation and release of the pre- and newly-formed mediators, β-hexosaminidase and LTB(4) by mast cells, activities that were potentiated in the presence of IgE. ArtinM also induced the activation of the transcription factors NFκB and NFAT, resulting in expression of some of their target genes such as IL-4 and TNF-α. In view of the established significance of mast cells in many immunological and inflammatory reactions, a better understanding of the mechanisms involved in mast cell activation by ArtinM is crucial to the pharmacological application of the lectin.

  10. Angiogenic activity mediates bone repair from human pluripotent stem cell-derived osteogenic cells

    PubMed Central

    Zou, Li; Chen, Qingshan; Quanbeck, Zachary; Bechtold, Joan E.; Kaufman, Dan S.

    2016-01-01

    Human pluripotent stem cells provide a standardized resource for bone repair. However, criteria to determine which exogenous cells best heal orthopedic injuries remain poorly defined. We evaluated osteogenic progenitor cells derived from both human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs). Phenotypic and genotypic analyses demonstrated that these hESCs/hiPSCs are similar in their osteogenic differentiation efficiency and they generate osteogenic cells comparable to osteogenic cells derived from mesenchymal stromal cells (BM-MSCs). However, expression of angiogenic factors, such as vascular endothelial growth factor and basic fibroblast growth factor in these osteogenic progenitor cells are markedly different, suggesting distinct pro-angiogenic potential of these stem cell derivatives. Studies to repair a femur non-union fracture demonstrate only osteogenic progenitor cells with higher pro-angiogenic potential significantly enhance bone repair in vivo. Together, these studies highlight a key role of pro-angiogenic potential of transplanted osteogenic cells for effective cell-mediated bone repair. PMID:26980556

  11. DNase I hypersensitive sites within the inducible qa gene cluster of Neurospora crassa.

    PubMed Central

    Baum, J A; Giles, N H

    1986-01-01

    DNase I hypersensitive regions were mapped within the 17.3-kilobase qa (quinic acid) gene cluster of Neurospora crassa. The 5'-flanking regions of the five qa structural genes and the two qa regulatory genes each contain DNase I hypersensitive sites under noninducing conditions and generally exhibit increases in DNase I cleavage upon induction of transcription with quinic acid. The two large intergenic regions of the qa gene cluster appear to be similarly organized with respect to the positions of constitutive and inducible DNase I hypersensitive sites. Inducible hypersensitive sites on the 5' side of one qa gene, qa-x, appear to be differentially regulated. Employing these and previously published data, we have identified a conserved sequence element that may mediate the activator function of the qa-1F regulatory gene. Variants of the 16-base-pair consensus sequence are consistently found within DNase I-protected regions adjacent to inducible DNase I hypersensitive sites within the gene cluster. Images PMID:2944110

  12. Calcium signaling as a mediator of cell energy demand and a trigger to cell death.

    PubMed

    Bhosale, Gauri; Sharpe, Jenny A; Sundier, Stephanie Y; Duchen, Michael R

    2015-09-01

    Calcium signaling is pivotal to a host of physiological pathways. A rise in calcium concentration almost invariably signals an increased cellular energy demand. Consistent with this, calcium signals mediate a number of pathways that together serve to balance energy supply and demand. In pathological states, calcium signals can precipitate mitochondrial injury and cell death, especially when coupled to energy depletion and oxidative or nitrosative stress. This review explores the mechanisms that couple cell signaling pathways to metabolic regulation or to cell death. The significance of these pathways is exemplified by pathological case studies, such as those showing loss of mitochondrial calcium uptake 1 in patients and ischemia/reperfusion injury.

  13. Calcium signaling as a mediator of cell energy demand and a trigger to cell death

    PubMed Central

    Bhosale, Gauri; Sharpe, Jenny A.; Sundier, Stephanie Y.

    2015-01-01

    Calcium signaling is pivotal to a host of physiological pathways. A rise in calcium concentration almost invariably signals an increased cellular energy demand. Consistent with this, calcium signals mediate a number of pathways that together serve to balance energy supply and demand. In pathological states, calcium signals can precipitate mitochondrial injury and cell death, especially when coupled to energy depletion and oxidative or nitrosative stress. This review explores the mechanisms that couple cell signaling pathways to metabolic regulation or to cell death. The significance of these pathways is exemplified by pathological case studies, such as those showing loss of mitochondrial calcium uptake 1 in patients and ischemia/reperfusion injury. PMID:26375864

  14. Lipid mediators in the neural cell nucleus: their metabolism, signaling, and association with neurological disorders.

    PubMed

    Farooqui, Akhlaq A

    2009-08-01

    Lipid mediators are important endogenous regulators of neural cell proliferation, differentiation, oxidative stress, inflammation, and apoptosis. They originate from enzymic degradation of glycerophospholipids, sphingolipids, and cholesterol by phospholipases, sphingomyelinases, and cytochrome P450 hydroxylases, respectively. Arachidonic acid-derived lipid mediators are called eicosanoids. Eicosanoids have emerged as key regulators of cell proliferation, differentiation, oxidative stress, and neuroinflammation. Another arachidonic acid-derived lipid mediator is lipoxin. Eicosanoids have proinflammatory effects, whereas lipoxins produce antiinflammatory effects. The crossponding lipid mediators of docosahexaenoic acid metabolism are named docosanoids. They include resolvins, protectins, and neuroprotectins. Docosanoids produce antioxidant, anti-inflammatory, and antiapoptotic effects in the brain tissue. Other glycerophospholipid-derived lipid mediators are platelet-activating factor, lysophosphatidic acid, and endocannabinoids. Degradation of sphingolipids also results in the generation of sphingolipid-derived lipid mediators. Sphingolipid-derived lipid mediators are ceramide, ceramide 1-phosphate, sphingosine, and sphingosine 1-phosphate. They mediate cellular differentiation, cell growth, and apoptosis. Similarly, cholesterol-derived lipid mediators hydroxycholesterol and oxycholesterol produce apoptosis. Most of these mediators originate from the plasma membrane. The nucleus has its own set of enzymes and lipid mediators that originate from the nuclear envelope and matrix. The purpose of this commentary is to describe basic and clinical information on lipid mediators in the nucleus.

  15. Stromal cell-mediated glycolytic switch in CLL cells involves Notch-c-Myc signaling.

    PubMed

    Jitschin, Regina; Braun, Martina; Qorraj, Mirjeta; Saul, Domenica; Le Blanc, Katarina; Zenz, Thorsten; Mougiakakos, Dimitrios

    2015-05-28

    It is well established that the stromal niche exerts a protective effect on chronic lymphocytic leukemia (CLL) cells, thereby also affecting their drug sensitivity. One hallmark of malignant cells is metabolic reprogramming, which is mostly represented by a glycolytic shift known as the Warburg effect. Because treatment resistance can be linked to metabolic alterations, we investigated whether bone marrow stromal cells impact the bioenergetics of primary CLL cells. In fact, stromal contact led to an increase of aerobic glycolysis and the cells' overall glycolytic capacity accompanied by an increased glucose uptake, expression of glucose transporter, and glycolytic enzymes. Activation of Notch signaling and of its direct transcriptional target c-Myc contributed to this metabolic switch. Based on these observations, CLL cells' acquired increased glucose dependency as well as Notch-c-Myc signaling could be therapeutically exploited in an effort to overcome stroma-mediated drug resistance.

  16. Hypersensitivity reactions associated with oxaliplatin.

    PubMed

    Saif, M Wasif

    2006-09-01

    The reported incidence of hypersensitivity reactions (HSRs) associated with oxaliplatin in patients with colorectal cancer (CRC) is approximately 12%, with 1 - 2% of patients developing grade 3 or 4 in severity. However, the recent rising incidence of HSR to oxaliplatin observed is the result of increasing clinical use. HSR to oxaliplatin may manifest as facial flushing, rash/hives, tachycardia, dyspnoea, erythema, pruritus, fever, tongue swelling, headache, chills, weakness, vomiting, burning sensations, dizziness and oedema. Anaphylactic shock is rare but serious, and must be considered in the event of hypotension. No definitive approaches to prevent and treat HSR associated with oxaliplatin are available; however, few successful strategies have been reported. Such strategies include: slowing the infusion rate, use of steroids and antagonists of type 1 and 2 histamine receptors, and desensitisation. Successful implementation of oxaliplatin desensitisation protocols based on other platinum-containing compounds have been reported, which could enable a small number of patients who experience severe HSR to further receive an effective therapy for CRC. However, reintroductions have only been reported as single case studies or small cohorts. Large-scale validation on desensitisation strategies are still missing. Recently, subcutaneous adrenaline has also been utilised as an alternative approach to manage HSR to oxaliplatin. Knowledge of this rare but real toxicity of oxaliplatin is paramount because the use of this drug continues to increase not only for the treatment of patients with stage II-IV CRC, but also other solid malignancies. In this article, the author discusses the incidence, clinical presentation, pathogenesis, risk factors and current strategies of management of HSR associated with oxaliplatin. PMID:16907658

  17. Annexin A6 regulates interleukin-2-mediated T-cell proliferation.

    PubMed

    Cornely, Rhea; Pollock, Abigail H; Rentero, Carles; Norris, Sarah E; Alvarez-Guaita, Anna; Grewal, Thomas; Mitchell, Todd; Enrich, Carlos; Moss, Stephen E; Parton, Robert G; Rossy, Jérémie; Gaus, Katharina

    2016-07-01

    Annexin A6 (AnxA6) has been implicated in cell signalling by contributing to the organisation of the plasma membrane. Here we examined whether AnxA6 regulates signalling and proliferation in T cells. We used a contact hypersensitivity model to immune challenge wild-type (WT) and AnxA6(-/-) mice and found that the in vivo proliferation of CD4(+) T cells, but not CD8(+) T cells, was impaired in AnxA6(-/-) relative to WT mice. However, T-cell migration and signalling through the T-cell receptor ex vivo was similar between T cells isolated from AnxA6(-/-) and WT mice. In contrast, interleukin-2 (IL-2) signalling was reduced in AnxA6(-/-) compared with WT T cells. Further, AnxA6-deficient T cells had reduced membrane order and cholesterol levels. Taken together, our data suggest that AnxA6 regulates IL-2 homeostasis and sensitivity in T cells by sustaining a lipid raft-like membrane environment. PMID:26853809

  18. Basophil Reactivity as Biomarker in Immediate Drug Hypersensitivity Reactions—Potential and Limitations

    PubMed Central

    Steiner, Markus; Harrer, Andrea; Himly, Martin

    2016-01-01

    Immediate drug hypersensitivity reactions (DHRs) resemble typical immunoglobulin E (IgE)-mediated symptoms. Clinical manifestations range from local skin reactions, gastrointestinal and/or respiratory symptoms to severe systemic involvement with potential fatal outcome. Depending on the substance group of the eliciting drug the correct diagnosis is a major challenge. Skin testing and in vitro diagnostics are often unreliable and not reproducible. The involvement of drug-specific IgE is questionable in many cases. The culprit substance (parent drug or metabolite) and potential cross-reacting compounds are difficult to identify, patient history and drug provocation testing often remain the only means for diagnosis. Hence, several groups proposed basophil activation test (BAT) for the diagnosis of immediate DHRs as basophils are well-known effector cells in allergic reactions. However, the usefulness of BAT in immediate DHRs is highly variable and dependent on the drug itself plus its capacity to spontaneously conjugate to serum proteins. Stimulation with pure solutions of the parent drug or metabolites thereof vs. drug-protein conjugates may influence sensitivity and specificity of the test. We thus, reviewed the available literature about the use of BAT for diagnosing immediate DHRs against drug classes such as antibiotics, radio contrast media, neuromuscular blocking agents, non-steroidal anti-inflammatory drugs, and biologicals. Influencing factors like the selection of stimulants or of the identification and activation markers, the stimulation protocol, gating strategies, and cut-off definition are addressed in this overview on BAT performance. The overall aim is to evaluate the suitability of BAT as biomarker for the diagnosis of immediate drug-induced hypersensitivity reactions. PMID:27378928

  19. Basophil Reactivity as Biomarker in Immediate Drug Hypersensitivity Reactions-Potential and Limitations.

    PubMed

    Steiner, Markus; Harrer, Andrea; Himly, Martin

    2016-01-01

    Immediate drug hypersensitivity reactions (DHRs) resemble typical immunoglobulin E (IgE)-mediated symptoms. Clinical manifestations range from local skin reactions, gastrointestinal and/or respiratory symptoms to severe systemic involvement with potential fatal outcome. Depending on the substance group of the eliciting drug the correct diagnosis is a major challenge. Skin testing and in vitro diagnostics are often unreliable and not reproducible. The involvement of drug-specific IgE is questionable in many cases. The culprit substance (parent drug or metabolite) and potential cross-reacting compounds are difficult to identify, patient history and drug provocation testing often remain the only means for diagnosis. Hence, several groups proposed basophil activation test (BAT) for the diagnosis of immediate DHRs as basophils are well-known effector cells in allergic reactions. However, the usefulness of BAT in immediate DHRs is highly variable and dependent on the drug itself plus its capacity to spontaneously conjugate to serum proteins. Stimulation with pure solutions of the parent drug or metabolites thereof vs. drug-protein conjugates may influence sensitivity and specificity of the test. We thus, reviewed the available literature about the use of BAT for diagnosing immediate DHRs against drug classes such as antibiotics, radio contrast media, neuromuscular blocking agents, non-steroidal anti-inflammatory drugs, and biologicals. Influencing factors like the selection of stimulants or of the identification and activation markers, the stimulation protocol, gating strategies, and cut-off definition are addressed in this overview on BAT performance. The overall aim is to evaluate the suitability of BAT as biomarker for the diagnosis of immediate drug-induced hypersensitivity reactions. PMID:27378928

  20. Dim light at night interferes with the development of the short-day phenotype and impairs cell-mediated immunity in Siberian hamsters (Phodopus sungorus).

    PubMed

    Aubrecht, Taryn G; Weil, Zachary M; Nelson, Randy J

    2014-10-01

    Winter is a challenging time to survive and breed outside of the tropics. Animals use day length (photoperiod) to regulate seasonally appropriate adaptations in anticipation of challenging winter conditions. The net result of these photoperiod-mediated adjustments is enhanced immune function and increased survival. Thus, the ability to discriminate day length information is critical for survival and reproduction in small animals. However, during the past century, urban and suburban development has rapidly expanded and filled the night sky with light from various sources, obscuring crucial light-dark signals, which alters physiological interpretation of day lengths. Furthermore, reduced space, increased proximity to people, and the presence of light at night may act as stressors for small animals. Whereas acute stressors typically enhance immune responses, chronic exposure to stressors often impairs immune responses. Therefore, we hypothesized that the combination of dim light at night and chronic stress interferes with enhanced cell-mediated immunity observed during short days. Siberian hamsters (Phodopus sungorus) were assigned to short or long days with dark nights (0 lux) or dim (5 lux) light at night for 10 weeks. Following 2 weeks of chronic restraint (6 hr/day), a model of chronic stress, delayed type hypersensitivity (DTH) responses were assessed. Both dim light at night and restraint reduced the DTH response. Dim light at night during long nights produced an intermediate short day phenotype. These results suggest the constant presence of light at night could negatively affect survival of photoperiodic rodents by disrupting the timing of breeding and immune responses.

  1. MicroRNA-155 Mediates Augmented CD40 Expression in Bone Marrow Derived Plasmacytoid Dendritic Cells in Symptomatic Lupus-Prone NZB/W F1 Mice

    PubMed Central

    Yan, Sheng; Yim, Lok Yan; Tam, Rachel Chun Yee; Chan, Albert; Lu, Liwei; Lau, Chak Sing; Chan, Vera Sau-Fong

    2016-01-01

    Systemic lupus erythematosus (SLE) is a chronic multi-organ autoimmune disease characterized by hyperactivated immune responses to self-antigens and persistent systemic inflammation. Previously, we reported abnormalities in circulating and bone marrow (BM)-derived plasmacytoid dendritic cells (pDCs) from SLE patients. Here, we aim to seek for potential regulators that mediate functional aberrations of pDCs in SLE. BM-derived pDCs from NZB/W F1 mice before and after the disease onset were compared for toll-like receptor (TLR) induced responses and microRNA profile changes. While pDCs derived from symptomatic mice were phenotypically comparable to pre-symptomatic ones, functionally they exhibited hypersensitivity to TLR7 but not TLR9 stimulation, as represented by the elevated upregulation of CD40, CD86 and MHC class II molecules upon R837 stimulation. Upregulated induction of miR-155 in symptomatic pDCs following TLR7 stimulation was observed. Transfection of miR-155 mimics in pre-symptomatic pDCs induced an augmented expression of Cd40, which is consistent with the increased CD40 expression in symptomatic pDCs. Overall, our results provide evidence for miR-155-mediated regulation in pDC functional abnormalities in SLE. Findings from this study contribute to a better understanding of SLE pathogenesis and ignite future interests in evaluating the molecular regulation in autoimmunity. PMID:27509492

  2. Micronutrient supplementation and T-cell mediated immune responses in patients with tuberculosis in Tanzania

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Limited studies exist regarding whether incorporating micronutrient supplements during tuberculosis (TB) treatment may improve cell-mediated immune response. We examine the effect of micronutrient supplementation on lymphocyte proliferation response to mycobacteria or T cell mitogens in a randomize...

  3. TLR5 mediates CD172α+ intestinal lamina propria dendritic cell induction of Th17 cells

    PubMed Central

    Liu, Han; Chen, Feidi; Wu, Wei; Cao, Anthony T; Xue, Xiaochang; Yao, Suxia; Evans-Marin, Heather L; Li, Yan-Qing; Cong, Yingzi

    2016-01-01

    Multiple mechanisms exist in regulation of host responses to massive challenges from microbiota to maintain immune homeostasis in the intestines. Among these is the enriched Th17 cells in the intestines, which regulates intestinal homeostasis through induction of antimicrobial peptides and secretory IgA among others. However, the means by which Th17 cells develop in response to microbiota is still not completely understood. Although both TLR5 and CD172α+ lamina propria dendritic cells (LPDC) have been shown to promote Th17 cell development, it is still unclear whether TLR5 mediates the CD172α+LPDC induction of Th17 cells. By using a microbiota antigen-specific T cell reporter mouse system, we demonstrated that microbiota antigen-specific T cells developed into Th17 cells in the intestinal LP, but not in the spleen when transferred into TCRβxδ−/− mice. LPDCs expressed high levels of TLR5, and most CD172α+LPDCs also co-expressed TLR5. LPDCs produced high levels of IL-23, IL-6 and TGFβ when stimulated with commensal flagellin and promoted Th17 cell development when cultured with full-length CBir1 flagellin but not CBir1 peptide. Wild-type CD172α+, but not CD172α−, LPDCs induced Th17 cells, whereas TLR5-deficient LPDC did not induce Th17 cells. Our data thereby demonstrated that TLR5 mediates CD172α+LPDC induction of Th17 cells in the intestines. PMID:26907705

  4. Cytomegalovirus-Infected Cells Resist T Cell Mediated Killing in an HLA-Recognition Independent Manner.

    PubMed

    Proff, Julia; Walterskirchen, Christian; Brey, Charlotte; Geyeregger, Rene; Full, Florian; Ensser, Armin; Lehner, Manfred; Holter, Wolfgang

    2016-01-01

    In order to explore the potential of HLA-independent T cell therapy for human cytomegalovirus (HCMV) infections, we developed a chimeric antigen receptor (CAR) directed against the HCMV encoded glycoprotein B (gB), which is expressed at high levels on the surface of infected cells. T cells engineered with this anti-gB CAR recognized HCMV-infected cells and released cytokines and cytotoxic granules. Unexpectedly, and in contrast to analogous approaches for HIV, Hepatitis B or Hepatitis C virus, we found that HCMV-infected cells were resistant to killing by the CAR-modified T cells. In order to elucidate whether this phenomenon was restricted to the use of CARs, we extended our experiments to T cell receptor (TCR)-mediated recognition of infected cells. To this end we infected fibroblasts with HCMV-strains deficient in viral inhibitors of antigenic peptide presentation and targeted these HLA-class I expressing peptide-loaded infected cells with peptide-specific cytotoxic T cells (CTLs). Despite strong degranulation and cytokine production by the T cells, we again found significant inhibition of lysis of HCMV-infected cells. Impairment of cell lysis became detectable 1 day after HCMV infection and gradually increased during the following 3 days. We thus postulate that viral anti-apoptotic factors, known to inhibit suicide of infected host cells, have evolved additional functions to directly abrogate T cell cytotoxicity. In line with this hypothesis, CAR-T cell cytotoxicity was strongly inhibited in non-infected fibroblasts by expression of the HCMV-protein UL37x1, and even more so by additional expression of UL36. Our data extend the current knowledge on Betaherpesviral evasion from T cell immunity and show for the first time that, beyond impaired antigen presentation, infected cells are efficiently protected by direct blockade of cytotoxic effector functions through viral proteins.

  5. Cytomegalovirus-Infected Cells Resist T Cell Mediated Killing in an HLA-Recognition Independent Manner

    PubMed Central

    Proff, Julia; Walterskirchen, Christian; Brey, Charlotte; Geyeregger, Rene; Full, Florian; Ensser, Armin; Lehner, Manfred; Holter, Wolfgang

    2016-01-01

    In order to explore the potential of HLA-independent T cell therapy for human cytomegalovirus (HCMV) infections, we developed a chimeric antigen receptor (CAR) directed against the HCMV encoded glycoprotein B (gB), which is expressed at high levels on the surface of infected cells. T cells engineered with this anti-gB CAR recognized HCMV-infected cells and released cytokines and cytotoxic granules. Unexpectedly, and in contrast to analogous approaches for HIV, Hepatitis B or Hepatitis C virus, we found that HCMV-infected cells were resistant to killing by the CAR-modified T cells. In order to elucidate whether this phenomenon was restricted to the use of CARs, we extended our experiments to T cell receptor (TCR)-mediated recognition of infected cells. To this end we infected fibroblasts with HCMV-strains deficient in viral inhibitors of antigenic peptide presentation and targeted these HLA-class I expressing peptide-loaded infected cells with peptide-specific cytotoxic T cells (CTLs). Despite strong degranulation and cytokine production by the T cells, we again found significant inhibition of lysis of HCMV-infected cells. Impairment of cell lysis became detectable 1 day after HCMV infection and gradually increased during the following 3 days. We thus postulate that viral anti-apoptotic factors, known to inhibit suicide of infected host cells, have evolved additional functions to directly abrogate T cell cytotoxicity. In line with this hypothesis, CAR-T cell cytotoxicity was strongly inhibited in non-infected fibroblasts by expression of the HCMV-protein UL37x1, and even more so by additional expression of UL36. Our data extend the current knowledge on Betaherpesviral evasion from T cell immunity and show for the first time that, beyond impaired antigen presentation, infected cells are efficiently protected by direct blockade of cytotoxic effector functions through viral proteins. PMID:27375569

  6. Cytomegalovirus-Infected Cells Resist T Cell Mediated Killing in an HLA-Recognition Independent Manner.

    PubMed

    Proff, Julia; Walterskirchen, Christian; Brey, Charlotte; Geyeregger, Rene; Full, Florian; Ensser, Armin; Lehner, Manfred; Holter, Wolfgang

    2016-01-01

    In order to explore the potential of HLA-independent T cell therapy for human cytomegalovirus (HCMV) infections, we developed a chimeric antigen receptor (CAR) directed against the HCMV encoded glycoprotein B (gB), which is expressed at high levels on the surface of infected cells. T cells engineered with this anti-gB CAR recognized HCMV-infected cells and released cytokines and cytotoxic granules. Unexpectedly, and in contrast to analogous approaches for HIV, Hepatitis B or Hepatitis C virus, we found that HCMV-infected cells were resistant to killing by the CAR-modified T cells. In order to elucidate whether this phenomenon was restricted to the use of CARs, we extended our experiments to T cell receptor (TCR)-mediated recognition of infected cells. To this end we infected fibroblasts with HCMV-strains deficient in viral inhibitors of antigenic peptide presentation and targeted these HLA-class I expressing peptide-loaded infected cells with peptide-specific cytotoxic T cells (CTLs). Despite strong degranulation and cytokine production by the T cells, we again found significant inhibition of lysis of HCMV-infected cells. Impairment of cell lysis became detectable 1 day after HCMV infection and gradually increased during the following 3 days. We thus postulate that viral anti-apoptotic factors, known to inhibit suicide of infected host cells, have evolved additional functions to directly abrogate T cell cytotoxicity. In line with this hypothesis, CAR-T cell cytotoxicity was strongly inhibited in non-infected fibroblasts by expression of the HCMV-protein UL37x1, and even more so by additional expression of UL36. Our data extend the current knowledge on Betaherpesviral evasion from T cell immunity and show for the first time that, beyond impaired antigen presentation, infected cells are efficiently protected by direct blockade of cytotoxic effector functions through viral proteins. PMID:27375569

  7. NK Cells and γδ T Cells Mediate Resistance to Polyomavirus–Induced Tumors

    PubMed Central

    Mishra, Rabinarayan; Chen, Alex T.; Welsh, Raymond M.; Szomolanyi-Tsuda, Eva

    2010-01-01

    NK and γδ T cells can eliminate tumor cells in many experimental models, but their effect on the development of tumors caused by virus infections in vivo is not known. Polyomavirus (PyV) induces tumors in neonatally infected mice of susceptible strains and in adult mice with certain immune deficiencies, and CD8+ αβ T cells are regarded as the main effectors in anti-tumor immunity. Here we report that adult TCRβ knockout (KO) mice that lack αβ but have γδ T cells remain tumor-free after PyV infection, whereas TCRβ×δ KO mice that lack all T cells develop tumors. In addition, E26 mice, which lack NK and T cells, develop the tumors earlier than TCRβ×δ KO mice. These observations implicate γδ T and NK cells in the resistance to PyV-induced tumors. Cell lines established from PyV-induced tumors activate NK and γδ T cells both in culture and in vivo and express Rae-1, an NKG2D ligand. Moreover, these PyV tumor cells are killed by NK cells in vitro, and this cytotoxicity is prevented by treatment with NKG2D-blocking antibodies. Our findings demonstrate a protective role for NK and γδ T cells against naturally occurring virus-induced tumors and suggest the involvement of NKG2D-mediated mechanisms. PMID:20523894

  8. ZnT2 is a critical mediator of lysosomal-mediated cell death during early mammary gland involution

    PubMed Central

    Hennigar, Stephen R.; Seo, Young Ah; Sharma, Supriya; Soybel, David I.; Kelleher, Shannon L.

    2015-01-01

    Mammary gland involution is the most dramatic example of physiological cell death. It occurs through an initial phase of lysosomal-mediated cell death (LCD) followed by mitochondrial-mediated apoptosis. Zinc (Zn) activates both LCD and apoptosis in vitro. The Zn transporter ZnT2 imports Zn into vesicles and mitochondria and ZnT2-overexpression activates cell death in mammary epithelial cells (MECs). We tested the hypothesis that ZnT2-mediated Zn transport is critical for mammary gland involution in mice. Following weaning, ZnT2 abundance increased in lysosomes and mitochondria, which paralleled Zn accumulation in each of these organelles. Adenoviral expression of ZnT2 in lactating mouse mammary glands in vivo increased Zn in lysosomes and mitochondria and activated LCD and apoptosis, promoting a profound reduction in MECs and alveoli. Injection of TNFα, a potent activator of early involution, into the mammary gland fat pads of lactating mice increased ZnT2 and Zn in lysosomes and activated premature involution. Exposure of cultured MECs to TNFα redistributed ZnT2 to lysosomes and increased lysosomal Zn, which activated lysosomal swelling, cathepsin B release, and LCD. Our data implicate ZnT2 as a critical mediator of cell death during involution and importantly, that as an initial involution signal, TNFα redistributes ZnT2 to lysosomes to activate LCD. PMID:25620235

  9. Involvement of NtERF3 in the cell death signalling pathway mediated by SIPK/WIPK and WRKY1 in tobacco plants.

    PubMed

    Ogata, T; Okada, H; Kawaide, H; Takahashi, H; Seo, S; Mitsuhara, I; Matsushita, Y

    2015-09-01

    We previously reported that one of the ethylene response factors (ERFs), NtERF3, and other members of the subgroup VIII-a ERFs of the AP2/ERF family exhibit cell death-inducing ability in tobacco leaves. In this study, we focused on the involvement of NtERF3 in a cell death signalling pathway in tobacco plants, particularly downstream of NtSIPK/NtWIPK and NtWRKY1, which are mitogen-activated protein kinases and a phosphorylation substrate of NtSIPK, respectively. An ERF-associated amphiphilic repression (EAR) motif-deficient NtERF3b mutant (NtERF3bΔEAR) that lacked cell death-inducing ability suppressed the induction of cell death caused by NtERF3a. The transient co-expression of NtERF3bΔEAR suppressed the hypersensitive reaction (HR)-like cell death induced by NtSIPK and NtWRKY1. The induction of cell death by NtSIPK and NtWRKY1 was also inhibited in transgenic plants expressing NtERF3bΔEAR. Analysis of gene expression, ethylene production and cell death symptoms in salicylic acid-deficient tobacco plants suggested the existence of some feedback regulation in the HR cell death signalling pathway mediated by SIPK/WIPK and WRKY1. Overall, these results suggest that NtERF3 functions downstream of NtSIPK/NtWIPK and NtWRKY1 in a cell death signalling pathway, with some feedback regulation.

  10. Potential Mechanisms for IgG4 Inhibition of Immediate Hypersensitivity Reactions.

    PubMed

    James, Louisa K; Till, Stephen J

    2016-03-01

    IgG4 is the least abundant IgG subclass in human serum, representing less than 5% of all IgG. Increases in IgG4 occur following chronic exposure to antigen and are generally associated with states of immune tolerance. In line with this, IgG4 is regarded as an anti-inflammatory antibody with a limited ability to elicit effective immune responses. Furthermore, IgG4 attenuates allergic responses by inhibiting the activity of IgE. The mechanism by which IgG4 inhibits IgE-mediated hypersensitivity has been investigated using a variety of model systems leading to two proposed mechanisms. First by sequestering antigen, IgG4 can function as a blocking antibody, preventing cross-linking of receptor bound IgE. Second IgG4 has been proposed to co-stimulate the inhibitory IgG receptor FcγRIIb, which can negatively regulate FcεRI signaling and in turn inhibit effector cell activation. Recent advances in our understanding of the structural features of human IgG4 have shed light on the unique functional and immunologic properties of IgG4. The aim of this review is to evaluate our current understanding of IgG4 biology and reassess the mechanisms by which IgG4 functions to inhibit IgE-mediated allergic responses.

  11. Intrathecal curcumin attenuates pain hypersensitivity and decreases spinal neuroinflammation in rat model of monoarthritis

    PubMed Central

    Chen, Jun-Jie; Dai, Lin; Zhao, Lin-Xia; Zhu, Xiang; Cao, Su; Gao, Yong-Jing

    2015-01-01

    Curcumin is a major component of turmeric and reportedly has anti-inflammatory and anti-oxidant effects. Neuroinflammation has been recognized to play an important role in the pathogenesis of various diseases in the central nervous system. Here we investigated the anti-nociceptive and anti-neuroinflammatory effect of curcumin on arthritic pain in rats. We found that repeated oral treatment with curcumin, either before or after complete Freund’s adjuvant (CFA) injection, dose-dependently attenuated CFA-induced mechanical allodynia and thermal hyperalgesia, but had no effect on joint edema. Repeated intrathecal injection of curcumin reversed CFA-induced pain hypersensitivity. Furthermore, such a curcumin treatment reduced CFA-induced activation of glial cells and production of inflammatory mediators [interleukin-1β (IL-1β), monocyte chemoattractant protein-1 (MCP-1), and monocyte inflammatory protein-1 (MIP-1α)] in the spinal cord. Curcumin also decreased lipopolysaccharide-induced production of IL-1β, tumor necrosis factor-α, MCP-1, and MIP-1α in cultured astrocytes and microglia. Our results suggest that intrathecal curcumin attenuates arthritic pain by inhibiting glial activation and the production of inflammatory mediators in the spinal cord, suggesting a new application of curcumin for the treatment of arthritic pain. PMID:25988362

  12. Intrathecal curcumin attenuates pain hypersensitivity and decreases spinal neuroinflammation in rat model of monoarthritis.

    PubMed

    Chen, Jun-Jie; Dai, Lin; Zhao, Lin-Xia; Zhu, Xiang; Cao, Su; Gao, Yong-Jing

    2015-01-01

    Curcumin is a major component of turmeric and reportedly has anti-inflammatory and anti-oxidant effects. Neuroinflammation has been recognized to play an important role in the pathogenesis of various diseases in the central nervous system. Here we investigated the anti-nociceptive and anti-neuroinflammatory effect of curcumin on arthritic pain in rats. We found that repeated oral treatment with curcumin, either before or after complete Freund's adjuvant (CFA) injection, dose-dependently attenuated CFA-induced mechanical allodynia and thermal hyperalgesia, but had no effect on joint edema. Repeated intrathecal injection of curcumin reversed CFA-induced pain hypersensitivity. Furthermore, such a curcumin treatment reduced CFA-induced activation of glial cells and production of inflammatory mediators [interleukin-1β (IL-1β), monocyte chemoattractant protein-1 (MCP-1), and monocyte inflammatory protein-1 (MIP-1α)] in the spinal cord. Curcumin also decreased lipopolysaccharide-induced production of IL-1β, tumor necrosis factor-α, MCP-1, and MIP-1α in cultured astrocytes and microglia. Our results suggest that intrathecal curcumin attenuates arthritic pain by inhibiting glial activation and the production of inflammatory mediators in the spinal cord, suggesting a new application of curcumin for the treatment of arthritic pain. PMID:25988362

  13. Anti-inflammatory and immune-regulatory mechanisms prevent contact hypersensitivity to Arnica montana L.

    PubMed

    Lass, Christian; Vocanson, Marc; Wagner, Steffen; Schempp, Christoph M; Nicolas, Jean-Francois; Merfort, Irmgard; Martin, Stefan F

    2008-10-01

    Sesquiterpene lactones (SL), secondary plant metabolites from flowerheads of Arnica, exert anti-inflammatory effects mainly by preventing nuclear factor (NF)-kappaB activation because of alkylation of the p65 subunit. Despite its known immunosuppressive action, Arnica has been classified as a plant with strong potency to induce allergic contact dermatitis. Here we examined the dual role of SL as anti-inflammatory compounds and contact allergens in vitro and in vivo. We tested the anti-inflammatory and allergenic potential of SL in the mouse contact hypersensitivity model. We also used dendritic cells to study the activation of NF-kappaB and the secretion of interleukin (IL)-12 in the presence of different doses of SL in vitro. Arnica tinctures and SL potently suppressed NF-kappaB activation and IL-12 production in dendritic cells at high concentrations, but had immunostimulatory effects at low concentrations. Contact hypersensitivity could not be induced in the mouse model, even when Arnica tinctures or SL were applied undiluted to inflamed skin. In contrast, Arnica tinctures suppressed contact hypersensitivity to the strong contact sensitizer trinitrochlorobenzene and activation of dendritic cells. However, contact hypersensitivity to Arnica tincture could be induced in acutely CD4-depleted MHC II knockout mice. These results suggest that induction of contact hypersensitivity by Arnica is prevented by its anti-inflammatory effect and immunosuppression as a result of immune regulation in immunocompetent mice.

  14. Manganese oxidation state mediates toxicity in PC12 cells

    SciTech Connect

    Reaney, S.H. . E-mail: stevereaney@hotmail.com; Smith, D.R.

    2005-06-15

    The role of the manganese (Mn) oxidation state on cellular Mn uptake and toxicity is not well understood. Therefore, undifferentiated PC12 cells were exposed to 0-200 {mu}M Mn(II)-chloride or Mn(III)-pyrophosphate for 24 h, after which cellular manganese levels were measured along with measures of cell viability, function, and cytotoxicity (trypan blue exclusion, medium lactate dehydrogenase (LDH), 8-isoprostanes, cellular ATP, dopamine, serotonin, H-ferritin, transferrin receptor (TfR), Mn-superoxide dismutase (MnSOD), and copper-zinc superoxide dismutase (CuZnSOD) protein levels). Exposures to Mn(III) >10 {mu}M produced 2- to 5-fold higher cellular manganese levels than equimolar exposures to Mn(II). Cell viability and ATP levels both decreased at the highest Mn(II) and Mn(III) exposures (150-200 {mu}M), while Mn(III) exposures produced increases in LDH activity at lower exposures ({>=}50 {mu}M) than did Mn(II) (200 {mu}M only). Mn(II) reduced cellular dopamine levels more than Mn(III), especially at the highest exposures (50% reduced at 200 {mu}M Mn(II)). In contrast, Mn(III) produced a >70% reduction in cellular serotonin at all exposures compared to Mn(II). Different cellular responses to Mn(II) exposures compared to Mn(III) were also observed for H-ferritin, TfR, and MnSOD protein levels. Notably, these differential effects of Mn(II) versus Mn(III) exposures on cellular toxicity could not simply be accounted for by the different cellular levels of manganese. These results suggest that the oxidation state of manganese exposures plays an important role in mediating manganese cytotoxicity.

  15. Hypersensitivity to hypercapnia: definition/(s).

    PubMed

    Vickers, Kristin

    2012-05-15

    Empirical evidence indicates that panic disorder (PD) patients experience hypersensitivity to hypercapnia, a condition in which the blood level of carbon dioxide exceeds the normal value. The importance of this research line is substantial and indeed, hypercapnic hypersensitivity has been advanced as a possible endophenotype of panic. Definitions of "hypersensitivity," however, have varied. The purpose of this brief review is to delineate and critique different definitions of hypercapnic hypersensitivity. Several definitions - panic attack rate, panic symptoms including dyspnea, subjective anxiety, and respiratory disturbance - are explored. The review concludes that although no ideal definition has emerged, marked anxiety post-hypercapnia has substantial support as a putative trait marker of PD. The term "subjective hypersensitivity" (Coryell et al., 2001) is re-introduced to denote pronounced anxiety post-hypercapnia and recommended for use along with its previous definition: increased self-reported anxiety measured on a continuous visual analog scale, already widely in use. Due to the well-established link between panic and respiration, definitional candidates focusing on aberrant respiratory response - less investigated as trait markers of PD in high risk studies - warrant scrutiny as well. Several reasons why definitional clarity might be beneficial are presented, along with ideas for future research.

  16. Power toothbrushes, gender, and dentin hypersensitivity.

    PubMed

    Hefti, A F; Stone, C

    2000-06-01

    Power toothbrushes require less force for plaque removal than manual brushes. In addition, in vitro studies have indicated that brushing with low force could occlude patent dentin tubules by formation of a smear layer. Hence, lessening the force necessary to remove plaque may reduce dentin hypersensitivity. However, it was recently suggested that the use of an oscillating/rotating power toothbrush could decrease tooth sensitivity as compared to a sonic power toothbrush. Therefore, the objective of the present research was to compare the effect on dentin hypersensitivity of two different types of power brushes, the Optiva Sonicare and the Braun Oral B Ultra Plaque Remover. The null hypothesis was tested in an 8-week, randomized, parallel group, examiner-blind clinical trial. Fifty-nine subjects with a history of dentin hypersensitivity participated. Dentin hypersensitivity-associated pain was elicited using tactile and evaporative stimuli and assessed using a visual analog scale (VAS) instrument. Clinical examinations were carried out at screening and baseline and repeated after 8 weeks of twice daily use of the power brushes. Data analysis was performed on VAS scores obtained at the final visit following adjustment for group differences at baseline. A 35% to 40% reduction in pain as compared to baseline was observed in both treatment groups. Treatment-related differences were not statistically significant. A gender-related effect on dentin hypersensitivity was observed using the tactile stimulus and may merit further investigation.

  17. Antibody- and cell-mediated immune responses of Actinobacillus pleuropneumoniae-infected and bacterin-vaccinated pigs.

    PubMed Central

    Furesz, S E; Mallard, B A; Bossé, J T; Rosendal, S; Wilkie, B N; MacInnes, J I

    1997-01-01

    Current porcine pleuropneumonia bacterins afford only partial protection by decreasing mortality but not morbidity. In order to better understand the type(s) of immune response associated with protection, antibody- and cell-mediated immune responses (CMIR) were compared for piglets before and after administration of a commercial bacterin, which confers partial protection, or a low-dose (10(5) CFU/ml) aerosol challenge with Actinobacillus pleuropneumoniae CM5 (LD), which induces complete protection. Control groups received phosphate-buffered saline or adjuvant. Serum antibody response, antibody avidity, delayed-type hypersensitivity (DTH), and lymphocyte blastogenic responses were measured and compared among treatment groups to the lipopolysaccharide (LPS), capsular polysaccharide (CPS), hemolysin (HLY), and outer membrane proteins (OMP) of A. pleuropneumoniae. Peripheral blood lymphocytes and sera were collected prior to and following primary and secondary immunization-infection and high-dose A. pleuropneumoniae CM5 (10(7) CFU/ml) aerosol challenge. Serum antibody and DTH, particularly that to HLY, differed significantly between treatment groups, and increases were associated with protection. LD-infected piglets had higher antibody responses (P < or = 0.01) and antibody avidity (P < or = 0.10) than bacterin-vaccinated and control groups. Anti-HLY antibodies were consistently associated with protection, whereas anti-LPS and anti-CPS antibodies were not. LD-infected animals had higher DTH responses, particularly to HLY, than bacterin-vaccinated pigs (P < or = 0.03). The LD-infected group maintained consistent blastogenic responses to HLY, LPS, CPS, and OMP over the course of infection, unlike the bacterin-vaccinated and control animals. These data suggest that the immune responses induced by a commercial bacterin are very different from those induced by LD aerosol infection and that current bacterins may be modified, for instance, by addition of HLY, so as to

  18. A conveniently prepared and hypersensitized small molecular fluorescent probe: Rapidly detecting free zinc ion in HepG2 cells and Arabidopsis.

    PubMed

    Gan, Xiaoping; Sun, Ping; Li, Hong; Tian, Xiaohe; Zhang, Baowei; Wu, Jieying; Tian, Yupeng; Zhou, Hongping

    2016-12-15

    In this paper, we reported a conveniently prepared fluorescent probe for zinc ions detection, which constructed by the condensation reaction between p-(benzothiazolyl)aniline with 4, 4- diethylaminesalicylaldehyde. The sensing ability of the probe toward zinc ions in vitro was tested by a series of UV-Vis and fluorescence spectroscopy studies, which showed that the probe possessed high sensitivity with a detection limit of 5.8nM and a rapid response time of 10s. We also carried out fluorescent bio-imaging of the probe for zinc ions in human liver hepatocellular carcinoma cells (HepG2), which showed that the probe could be utilized to detect the intracellular endogenous zinc ions visually without introducing external zinc sources. Meanwhile, co-staining experiment with organelle selective trackers was performed to illustrate that the probe could locate at endoplasmic reticulum. Finally, we successfully used it as a zinc ion developer in plant tissue, which clearly demonstrated the distribution of zinc ions in the growth stage of plant tissue. PMID:27414244

  19. Effects of reactive nitrogen scavengers on NK-cell-mediated killing of K562 cells.

    PubMed

    Zeng, Yili; Huang, Qinmiao; Zheng, Meizhu; Guo, Jianxin; Pan, Jingxin

    2012-01-01

    This study explored the effects of reactive nitrogen metabolites (RNMS) on natural-killer- (NK-) cell-mediated killing of K562 cells and the influence of RNM scavengers, such as tiopronin (TIP), glutamylcysteinylglycine (GSH), and histamine dihydrochloride (DHT), on reversing the suppressing effect of RNM. We administered exogenous and endogenous RNM in the NK + K562 culture system and then added RNM scavengers. The concentrations of RNM, TNF-β and IFN-γ, and NK-cell cytotoxicity (NCC) and the percentage of living NK cells were then examined. We found that both exogenous and endogenous RNM caused the KIR to decrease (P < 0.01); however, RNM scavengers such as TIP and GSH rescued this phenomenon dose dependently. In conclusion, our data suggests that RNM scavengers such as TIP and GSH enhance the antineoplasmic activity of NK cells.

  20. Specialized proresolving mediators enhance human B cell differentiation to antibody secreting cells1

    PubMed Central

    Ramon, Sesquile; Gao, Fei; Serhan, Charles N.; Phipps, Richard P.

    2012-01-01

    The resolution of inflammation is an active and dynamic process critical in maintaining homeostasis. Newly identified lipid mediators have been recognized as key players during the resolution phase. These specialized proresolving mediators (SPM) constitute separate families that include lipoxins, resolvins, protectins and maresins each derived from essential polyunsaturated fatty acids. New results demonstrate that SPM regulate aspects of the immune response, including reduction of neutrophil infiltration, decreased T cell cytokine production and stimulation of macrophage phagocytic activity. The actions of SPM on B lymphocytes remain unknown. Our study shows for the first time that the novel SPM 17-hydroxydosahexaenoic acid (17-HDHA), resolvin D1 (RvD1) and protectin D1 (PD1) are present in the spleen. Interestingly, 17-HDHA, RvD1 but not PD1, strongly increase activated human B cell IgM and IgG production. Furthermore, increased antibody production by 17-HDHA is due to augmented B cell differentiation towards a CD27+CD38+ antibody-secreting cell phenotype. 17-HDHA did not affect proliferation and was non-toxic to cells. Increase of plasma cell differentiation and antibody production supports the involvement of SPM during the late stages of inflammation and pathogen clearance. The present study provides new evidence for SPM activity in the humoral response. These new findings highlight the potential applications of SPM as endogenous and non-toxic adjuvants, and as anti-inflammatory therapeutic molecules. PMID:22711890

  1. Cell permeable ITAM constructs for the modulation of mediator release in mast cells.

    PubMed

    Kuil, Joeri; Fischer, Marcel J E; de Mol, Nico J; Liskamp, Rob M J

    2011-02-01

    Spleen tyrosine kinase (Syk) is essential for high affinity IgE receptor (FcεRI) mediated mast cell degranulation. Once FcεRI is stimulated, intracellular ITAM motifs of the receptor are diphosphorylated (dpITAM) and Syk is recruited to the receptor by binding of the Syk tandem SH2 domain to dpITAM, resulting in activation of Syk and, eventually, degranulation. To investigate intracellular effects of ITAM mimics, constructs were synthesized with ITAM mimics conjugated to different cell penetrating peptides, i.e. Tat, TP10, octa-Arg and K(Myr)KKK, or a lipophilic C(12)-chain. In most constructs the cargo and carrier were linked to each other through a disulfide bridge, which is convenient for combining different cargos with different carriers and has the advantage that the cargo and the carrier may be separated by reduction of the disulfide once it is intracellular. The ability of these ITAM constructs to label RBL-2H3 cells was assessed using flow cytometry. Fluorescence microscopy showed that the octa-Arg-SS-Flu-ITAM construct was present in various parts of the cells, although it was not homogeneously distributed. In addition, cell penetrating constructs without fluorescent labels were synthesized to examine degranulation in RBL-2H3 cells. Octa-Arg-SS-ITAM stimulated the mediator release up to 140%, indicating that ITAM mimics may have the ability to activate non-receptor bound Syk.

  2. Restoring E-cadherin-mediated cell-cell adhesion increases PTEN protein level and stability in human breast carcinoma cells

    SciTech Connect

    Li Zengxia; Wang Liying; Zhang Wen; Fu Yi; Zhao Hongbo; Hu Yali; Prins, Bram Peter; Zha Xiliang

    2007-11-09

    The phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a well-characterized tumor suppressor that negatively regulates cell growth and survival. Despite the critical role of PTEN in cell signaling, the mechanisms of its regulation are still under investigation. We reported here that PTEN expression could be controlled by overexpression or knock-down of E-cadherin in several mammary carcinoma cell lines. Furthermore, we showed that the accumulation of PTEN protein in E-cadherin overexpressing cells was due to increased PTEN protein stability rather than the regulation of its transcription. The proteasome-dependent PTEN degradation pathway was impaired after restoring E-cadherin expression. Moreover, maintenance of E-cadherin mediated cell-cell adhesion was necessary for its regulating PTEN. Altogether, our results suggested that E-cadherin mediated cell-cell adhesion was essential for preventing the proteasome degradation of PTEN, which might explain how breast carcinoma cells which lost cell-cell contact proliferate rapidly and are prone to metastasis.

  3. Small CD4 Mimetics Prevent HIV-1 Uninfected Bystander CD4 + T Cell Killing Mediated by Antibody-dependent Cell-mediated Cytotoxicity

    PubMed Central

    Richard, Jonathan; Veillette, Maxime; Ding, Shilei; Zoubchenok, Daria; Alsahafi, Nirmin; Coutu, Mathieu; Brassard, Nathalie; Park, Jongwoo; Courter, Joel R.; Melillo, Bruno; Smith, Amos B.; Shaw, George M.; Hahn, Beatrice H.; Sodroski, Joseph; Kaufmann, Daniel E.; Finzi, Andrés

    2015-01-01

    Human immunodeficiency virus type 1 (HIV-1) infection causes a progressive depletion of CD4 + T cells. Despite its importance for HIV-1 pathogenesis, the precise mechanisms underlying CD4 + T-cell depletion remain incompletely understood. Here we make the surprising observation that antibody-dependent cell-mediated cytotoxicity (ADCC) mediates the death of uninfected bystander CD4 + T cells in cultures of HIV-1-infected cells. While HIV-1-infected cells are protected from ADCC by the action of the viral Vpu and Nef proteins, uninfected bystander CD4 + T cells bind gp120 shed from productively infected cells and are efficiently recognized by ADCC-mediating antibodies. Thus, gp120 shedding represents a viral mechanism to divert ADCC responses towards uninfected bystander CD4 + T cells. Importantly, CD4-mimetic molecules redirect ADCC responses from uninfected bystander cells to HIV-1-infected cells; therefore, CD4-mimetic compounds might have therapeutic utility in new strategies aimed at specifically eliminating HIV-1-infected cells. PMID:26870823