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1.
Methods Inf Med ; 51(3): 229-41, 2012.
Article in English | MEDLINE | ID: mdl-22311158

ABSTRACT

OBJECTIVE: To qualify the use of patient clinical records as non-human-subject for research purpose, electronic medical record data must be de-identified so there is minimum risk to protected health information exposure. This study demonstrated a robust framework for structured data de-identification that can be applied to any relational data source that needs to be de-identified. METHODS: Using a real world clinical data warehouse, a pilot implementation of limited subject areas were used to demonstrate and evaluate this new de-identification process. Query results and performances are compared between source and target system to validate data accuracy and usability. RESULTS: The combination of hashing, pseudonyms, and session dependent randomizer provides a rigorous de-identification framework to guard against 1) source identifier exposure; 2) internal data analyst manually linking to source identifiers; and 3) identifier cross-link among different researchers or multiple query sessions by the same researcher. In addition, a query rejection option is provided to refuse queries resulting in less than preset numbers of subjects and total records to prevent users from accidental subject identification due to low volume of data. This framework does not prevent subject re-identification based on prior knowledge and sequence of events. Also, it does not deal with medical free text de-identification, although text de-identification using natural language processing can be included due its modular design. CONCLUSION: We demonstrated a framework resulting in HIPAA Compliant databases that can be directly queried by researchers. This technique can be augmented to facilitate inter-institutional research data sharing through existing middleware such as caGrid.


Subject(s)
Databases, Factual , Medical Records Systems, Computerized/instrumentation , Privacy , Access to Information , Health Insurance Portability and Accountability Act , Humans , Pilot Projects , United States
2.
Nat Cell Biol ; 14(2): 159-67, 2011 Dec 18.
Article in English | MEDLINE | ID: mdl-22179046

ABSTRACT

PTEN (Phosphatase and tensin homolog deleted on chromosome 10) expression in stromal fibroblasts suppresses epithelial mammary tumours, but the underlying molecular mechanisms remain unknown. Using proteomic and expression profiling, we show that Pten loss from mammary stromal fibroblasts activates an oncogenic secretome that orchestrates the transcriptional reprogramming of other cell types in the microenvironment. Downregulation of miR-320 and upregulation of one of its direct targets, ETS2 (v-ets erythroblastosis virus E26 oncogene homolog 2) are critical events in Pten-deleted stromal fibroblasts responsible for inducing this oncogenic secretome, which in turn promotes tumour angiogenesis and tumour-cell invasion. Expression of the Pten-miR-320-Ets2-regulated secretome distinguished human normal breast stroma from tumour stroma and robustly correlated with recurrence in breast cancer patients. This work reveals miR-320 as a critical component of the Pten tumour-suppressor axis that acts in stromal fibroblasts to reprogramme the tumour microenvironment and curtail tumour progression.


Subject(s)
Gene Expression Profiling , Gene Expression Regulation, Neoplastic , MicroRNAs/genetics , PTEN Phosphohydrolase/genetics , Tumor Microenvironment/genetics , Animals , Blotting, Western , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , COS Cells , Cell Line, Tumor , Chlorocebus aethiops , Female , Fibroblasts/metabolism , Humans , Kaplan-Meier Estimate , Mammary Neoplasms, Experimental/genetics , Mammary Neoplasms, Experimental/metabolism , Mammary Neoplasms, Experimental/pathology , Mice , Mice, Knockout , MicroRNAs/metabolism , Oligonucleotide Array Sequence Analysis , PTEN Phosphohydrolase/metabolism , Proto-Oncogene Protein c-ets-2/genetics , Proto-Oncogene Protein c-ets-2/metabolism , RNA Interference , Reverse Transcriptase Polymerase Chain Reaction , Stromal Cells/metabolism
3.
Exp Clin Endocrinol Diabetes ; 117(3): 129-34, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18563681

ABSTRACT

Obstructive sleep apnea (OSA), characterized by cyclic intermittent hypoxia (IH) during sleep, is an independent risk factor for cardiovascular disease. Adiponectin (APN), an adipocytokine secreted exclusively by adipocytes, possesses antiatherogenic properties. Low levels of APN, particularly the high-molecular-weight (HMW) form, are associated with an increased risk of cardiovascular disease. Here, we hypothesized that IH would result in the dysregulation of APN expression and secretion. 3T3-L1 adipocytes were exposed to IH at 12 cycles/h for 6 h/d to simulate the IH condition similar to that encountered in OSA. Control adipocytes were exposed to 21% O(2) under identical conditions. After 48 h of incubation, IH caused a decrease in the secretion of total and HMW APN in spite of a significant upregulation of APN mRNA expression by adipocytes. This study suggested a novel mechanism of how the cyclic hypoxemia in OSA predisposes OSA patients to cardiovascular disease through the dysregulation of secretion of APN by adipocytes. Further studies are needed to determine the exact molecular mechanism how IH reduces the release of APN by adipocytes.


Subject(s)
Adipocytes/metabolism , Adiponectin/metabolism , 3T3-L1 Cells , Adipocytes/cytology , Adiponectin/genetics , Animals , Cell Hypoxia/physiology , Cell Shape , Gene Expression Regulation/genetics , Mice , Molecular Weight , RNA, Messenger/genetics
4.
Biochem Biophys Res Commun ; 373(4): 607-12, 2008 Sep 05.
Article in English | MEDLINE | ID: mdl-18602365

ABSTRACT

Crk is a member of a family of adaptor proteins that are involved in intracellular signal pathways altering cell adhesion, proliferation, and migration. Increased expression of Crk has been described in lung cancer and associated with increased tumor invasiveness. MicroRNAs (miRNAs) are a family of small non-coding RNAs (approximately 21-25 nt long) that are capable of targeting genes for either degradation of mRNA or inhibition of translation. Crk is a predicted putative target gene for miR-126. Over-expression of miR126 in a lung cancer cell line resulted in a decrease in Crk protein without any alteration in the associated mRNA. These lung cancer cells exhibit a decrease in adhesion, migration, and invasion. Decreased cancer cell invasion was also evident following targeted knockdown of Crk. MiR-126 alters lung cancer cell phenotype by inhibiting adhesion, migration, and invasion and the effects on invasion may be partially mediated through Crk regulation.


Subject(s)
Carcinoma, Non-Small-Cell Lung/pathology , Gene Expression Regulation, Neoplastic , Lung Neoplasms/pathology , MicroRNAs/metabolism , Proto-Oncogene Proteins c-crk/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Adhesion/genetics , Cell Line, Tumor , Cell Movement/genetics , Humans , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , MicroRNAs/genetics , Neoplasm Invasiveness , Proto-Oncogene Proteins c-crk/metabolism , RNA, Messenger/metabolism
5.
J Leukoc Biol ; 69(3): 435-9, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11261791

ABSTRACT

Leukocyte recruitment to the kidney in immune complex disease like systemic lupus erythematosus (SLE) is mediated in part by local expression of chemokines such as monocyte chemoattractant protein-1 (MCP-1). Recent studies from this laboratory demonstrated that cross-linking Fc gammaR on lymphocytes causes release of a soluble factor that induces monocyte chemokine production. To explain the induction of renal chemokine expression in immune complex disease, we postulated that this lymphocyte factor stimulates renal parenchymal cell MCP-1 expression. To test this hypothesis, human peripheral blood lymphocytes were incubated on immobilized IgG, a model for immune complex Fc gammaR cross-linking. Supernatants from these lymphocyte cultures significantly increased MCP-1 production by human mesangial, glomerular capillary endothelial, and proximal tubular epithelial cells. Mesangial cells incubated on immobilized IgG or with soluble, preformed immune complexes did not secrete MCP-1 above control levels. Lymphocyte supernatant-induced MCP-1 production appeared to be dependent on the presence of interleukin (IL)-1beta in the supernatant. Removing IL-1beta from the supernatants, antagonizing its activity, or preventing conversion to mature IL-1beta abrogated renal cell MCP-1 expression by the lymphocyte supernatants. These data demonstrate that in response to cross-linking Fc gammaR, lymphocytes induce renal cell MCP-1 expression by secreting IL-1beta. Renal chemokine expression in immune complex disease may thus be triggered as lymphocytes traffic through the kidney and encounter deposited immune complexes.


Subject(s)
Chemokine CCL2/biosynthesis , Interleukin-1/physiology , Kidney/metabolism , Lymphocytes/immunology , Receptors, IgG/metabolism , Antigen-Antibody Complex/immunology , Antigen-Antibody Complex/metabolism , Cells, Cultured , Humans , Immunoglobulin G/immunology , Immunoglobulin G/pharmacology , Interleukin-1/antagonists & inhibitors , Kidney/cytology , Kidney/immunology , Lymphocyte Activation/immunology , Lymphocytes/metabolism , Receptors, IgG/immunology
6.
J Biol Chem ; 274(37): 26393-8, 1999 Sep 10.
Article in English | MEDLINE | ID: mdl-10473597

ABSTRACT

The signaling pathways activated by the macrophage colony-stimulating factor (M-CSF) to promote survival of monocyte and macrophage lineage cells are not well established. In an effort to elucidate these pathways, we have used two cell types responsive to M-CSF: NIH 3T3 fibroblasts genetically engineered to express human M-CSF receptors (3T3-FMS cells) and human monocytes. M-CSF treatment induced M-CSF receptor tyrosine phosphorylation and recruitment of the p85 subunit of phosphatidylinositol 3-kinase (PI3K) to these receptors. These M-CSF receptor events correlated with activation of the serine/threonine kinase Akt. To clarify that PI3K products activate Akt in response to M-CSF, NIH 3T3 fibroblasts expressing mutant human M-CSF receptors (3T3-FMS(Y809F)) that fail to activate Ras in response to M-CSF also exhibit increased Akt kinase activity in response to M-CSF challenge. Furthermore, Akt appears to be the primary regulator of survival in 3T3-FMS cells, as transfection of genes encoding dominant-negative Akt isoforms into these fibroblasts blocked M-CSF-induced survival. In normal human monocytes, M-CSF increased the levels of tyrosine-phosphorylated proteins and induced Akt activation in a PI3K-dependent manner. The PI3K inhibitor LY294002 blocked M-CSF-mediated monocyte survival, an effect that was partially restored by caspase-9 inhibitors. These data suggest that M-CSF may induce cell survival through Akt-induced suppression of caspase-9 activation.


Subject(s)
Cell Survival/physiology , Macrophage Colony-Stimulating Factor/physiology , Protein Serine-Threonine Kinases , Proto-Oncogene Proteins/metabolism , 3T3 Cells , Animals , Caspase 9 , Caspases/metabolism , Cysteine Proteinase Inhibitors/pharmacology , Humans , Mice , Monocytes/drug effects , Monocytes/enzymology , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt
7.
J Immunol ; 162(10): 6217-25, 1999 May 15.
Article in English | MEDLINE | ID: mdl-10229867

ABSTRACT

IgG deposition at tissue sites characteristically leads to macrophage accumulation and organ injury. Although the mechanism by which deposited IgG induces tissue injury is not known, we have recently demonstrated that deposited IgG stimulates the release of IL-8 and monocyte chemoattractant protein-1 from normal human monocytes, which may drive inflammation. Since IgG also induces macrophage accumulation in these diseases, we hypothesized that deposited IgG protects monocytes from apoptosis. As an in vitro model of the effect of deposited IgG on monocyte survival, monocyte apoptosis was studied after FcgammaR cross-linking. Monocytes cultured on immobilized IgG, which induces FcgammaR cross-linking, were protected from apoptosis, whereas monocytes cultured with equivalent concentrations of F(ab')2 IgG or 50 times higher concentrations of soluble IgG, neither of which induces FcgammaR cross-linking, were not protected. Moreover, this protection was transferable, as supernatants from immobilized IgG-stimulated monocytes protected freshly isolated monocytes from apoptosis and contained functional M-CSF, a known monocyte survival factor. M-CSF mediated the monocyte survival induced by FcgammaR cross-linking, as neutralizing anti-human M-CSF Abs blocked the monocyte protection provided by either immobilized IgG or IgG-stimulated monocyte supernatants. These findings demonstrate a novel mechanism by which deposited IgG targets tissue macrophage accumulation through FcgammaR-mediated M-CSF release. This pathway may play an important role in promoting and potentiating IgG-mediated tissue injury.


Subject(s)
Antigen-Antibody Complex/immunology , Immunoglobulin G/immunology , Macrophage Colony-Stimulating Factor/metabolism , Monocytes/immunology , Apoptosis , Cell Survival , Humans , Immune Complex Diseases/immunology , Immunoglobulin Fab Fragments/immunology , Immunologic Capping , Macrophages/immunology , Monocytes/cytology , Receptors, IgG/metabolism
8.
Pharmacotherapy ; 18(6): 1365-74, 1998.
Article in English | MEDLINE | ID: mdl-9855341

ABSTRACT

We hypothesized that a pharmacist-provided comprehensive education program in conjunction with care provided by a pulmonologist would lead to improved economic, clinical, and humanistic outcomes in adults with asthma, compared with similar patients receiving care from a pulmonologist alone. The experimental group reported receiving more information about asthma self-management (p=0.001), were more likely to monitor peak flow readings (p=0.004), and had increased satisfaction with care, and perceived higher quality of care. Both groups had less lost productivity, fewer emergency department visits, fewer hospitalizations, and fewer physician visits, as well as improvement in symptoms scores within 45 days. Both groups improved in all functional status domains except the mental component score of the SF-12. Our results show a positive impact on outcomes in adults with asthma who received pharmaceutical care.


Subject(s)
Asthma/drug therapy , Outcome Assessment, Health Care , Adult , Aged , Asthma/economics , Asthma/prevention & control , Data Interpretation, Statistical , Health Care Costs/statistics & numerical data , Humans , Middle Aged , Patient Education as Topic , Patient Satisfaction , Pharmacists , Quality of Life , Self Care
9.
J Immunol ; 160(8): 3942-8, 1998 Apr 15.
Article in English | MEDLINE | ID: mdl-9558101

ABSTRACT

Neutrophils mediate tissue injury in response to immune complexes, although the factors that induce their recruitment are incompletely understood. We have reported that lymphocytes may be important regulators of monocyte and macrophage IL-8 release in the presence of immobilized IgG. Since tissue parenchymal cells are important local producers of IL-8 but are not directly stimulated by FcgammaR cross-linking, we hypothesized that lymphocytes may also regulate parenchymal IL-8 release. Supernatants from lymphocytes incubated on immobilized IgG induced primary human fibroblasts and human mesangial cells to produce IL-8 (17 +/- 3.5 and 44 +/- 8 ng/ml, respectively). Fibroblast and mesangial cell IL-8 mRNA levels were similarly increased by the conditioned lymphocyte supernatant. Immobilized anti-human FcgammaRIII, but not FcgammaRI or FcgammaRII Abs, could stimulate this IL-8-inducing activity in lymphocytes, suggesting that FcgammaRIII-bearing lymphocytes were responsible. Supernatants from lymphocytes incubated on immobilized IgG contained 2.2 +/- 0.8 ng/ml of IL-1beta, while enriched monocyte preparations from the same donors incubated on immobilized IgG released only 0.1 +/- 0.04 ng/ml of IL-1beta (p = 0.05). Consistent with the identification of IL-1beta as the lymphocyte factor, fibroblast or mesangial cell IL-8 release induced by the IgG-stimulated lymphocyte supernatants was inhibited by 1) the combination of IL-1R antagonist and soluble type II IL-1R, 2) an IL-1-converting enzyme inhibitor, or 3) anti-IL-1beta but not preimmune Abs. These data suggest that targeted deposits of IgG can stimulate FcgammaRIII-bearing lymphocytes to produce IL-1beta, which induces parenchymal cell IL-8 release.


Subject(s)
Interleukin-1/biosynthesis , Interleukin-8/metabolism , Lymphocytes/immunology , Receptors, IgG/metabolism , Cells, Cultured , Cross-Linking Reagents , Culture Media, Conditioned , Fibroblasts/immunology , Glomerular Mesangium/immunology , Humans , Immunoglobulin G/pharmacology , Interleukin-1/antagonists & inhibitors , Interleukin-1/pharmacology , Interleukin-8/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Receptors, IgG/chemistry
10.
J Clin Invest ; 100(6): 1416-24, 1997 Sep 15.
Article in English | MEDLINE | ID: mdl-9294107

ABSTRACT

Cytoplasmic antineutrophil cytoplasmic antibodies (cANCA) that accompany the neutrophilic vasculitis seen in Wegener's granulomatosis (WG), are directed against proteinase-3 (PR-3), a serine proteinase which is located in azurophilic granules of neutrophils and monocytes. PR-3, when expressed on the surface of TNFalpha-primed neutrophils, can directly activate neutrophils by complexing cANCA and promoting concomitant Fcgamma receptor (FcgammaR) cross-linking. Although the neutrophil's pathogenic role in WG has been studied, the role of the monocyte has not been explored. The monocyte, with its ability to release cytokines and regulate neutrophil influx, also expresses PR-3. Therefore, the monocyte may play a significant role in WG via the interaction of surface PR-3 with cANCA, inducing cytokine release by the monocyte. To test this hypothesis, monocytes were studied for PR-3 expression and for IL-8 release in response to cANCA IgG. PBMC obtained from healthy donors displayed dramatic surface PR-3 expression as detected by immunohistochemistry and flow cytometry in response to 0. 5-h pulse with TNFalpha (2 ng/ml). Purified monoclonal anti-PR-3 IgG added to TNFalpha-primed PBMC induced 45-fold more IL-8 release than an isotype control antibody. Furthermore, alpha 1-antitrypsin (alpha1-AT), the primary PR-3 antiprotease, inhibited the anti-PR-3 induced IL-8 release by 80%. Importantly, Fab and F(ab')2 fragments of anti-PR-3 IgG, which do not result in Fcgamma receptor cross-linking, do not induce IL-8 release. As a correlate, IgG isolated from cANCA positive patients with WG induced six times as much PBMC IL-8 release as compared to IgG isolated from normal healthy volunteers. Consistent with PR-3 associated IL-8 induction, alpha1-AT significantly inhibited this effect. These observations suggest that cANCA may recruit and target neutrophils through promoting monocyte IL-8 release. This induction is mediated via Fcgamma receptor cross-linking and is regulated in part by alpha1-AT.


Subject(s)
Antibodies, Antineutrophil Cytoplasmic/metabolism , Granulomatosis with Polyangiitis/immunology , Interleukin-8/metabolism , Monocytes/metabolism , Receptors, IgG/metabolism , Serine Endopeptidases/metabolism , alpha 1-Antitrypsin/pharmacology , Antibodies, Monoclonal/pharmacology , Cells, Cultured , Cross-Linking Reagents/pharmacology , Cycloheximide/pharmacology , Dose-Response Relationship, Drug , Humans , Immunoglobulin Fab Fragments/pharmacology , Immunohistochemistry , Monocytes/drug effects , Myeloblastin , Serine Endopeptidases/immunology , Tumor Necrosis Factor-alpha/pharmacology
11.
J Immunol ; 158(3): 1078-84, 1997 Feb 01.
Article in English | MEDLINE | ID: mdl-9013945

ABSTRACT

Immune complexes activate cells by cross-linking leukocyte surface Fc(gamma)Rs. Diseases associated with immune complex deposition, such as rheumatoid arthritis, glomerulonephritis, or idiopathic pulmonary fibrosis, are characterized by compartmentalized monocyte infiltration. The factors that recruit monocytes to these compartments are not well characterized; however, monocyte chemoattractant protein-1 (MCP-1) has been found in areas of tissue injury. To account for these observations we hypothesized that PBMC Fc(gamma)R cross-linking may induce MCP-1 synthesis, which stimulates further monocyte recruitment. To test this hypothesis, PBMC were incubated on increasing concentrations of immobilized human IgG, a stimulus for Fc(gamma)R cross-linking. Immunoreactive MCP-1 was produced in a dose-dependent manner (p < 0.0001). MCP-1 was specifically induced by Fc(gamma)R cross-linking, since immobilized F(ab')2 fragments of human IgG did not activate MCP-1 production. This effect was reproduced by directly cross-linking PBMC Fc(gamma)RIII, but not by cross-linking Fc(gamma)RI or Fc(gamma)RII. PBMC-derived MCP-1 stimulated monocyte chemotaxis that was inhibited by a neutralizing anti-MCP-1 Ab. MCP-1 levels correlated with increased PBMC mRNA expression. Interestingly, Fc(gamma)R cross-linking with either immobilized IgG or anti-Fc(gamma)RIII induced more MCP-1 release from PBMC than from autologous monocytes (p = 0.02). Lymphocytes, the main cell type found in PBMC preparations, did not independently produce a significant amount of MCP-1, but when incubated on immobilized IgG or anti-Fc(gamma)RIII secreted a soluble factor(s) that induced monocyte MCP-1 production. These data suggest that cross-linking PBMC Fc(gamma)R induces the production of bioactive MCP-1. This occurs in part at the level of gene transcription and involves a cooperative interaction between monocytes and lymphocytes.


Subject(s)
Chemokine CCL2/biosynthesis , Immunoglobulin G/immunology , Lymphocytes/immunology , Monocytes/metabolism , Receptors, IgG/physiology , Cells, Cultured , Humans , Receptor Aggregation , Signal Transduction
13.
Cytokine ; 8(11): 828-36, 1996 Nov.
Article in English | MEDLINE | ID: mdl-9047079

ABSTRACT

Soluble type II interleukin 1 receptor (IL-1r II) and interleukin 1 receptor antagonist (IL-1ra) regulate inflammation by competitively inhibiting the binding of IL-1 beta to the signalling IL-1 receptor. In addition, glucocorticoids also regulate IL-1 beta by suppressing gene transcription. More recently, glucocorticoids have been shown to increase soluble IL-1r II concentrations, which may contribute to their anti-inflammatory properties. Interestingly, increased serum levels of soluble IL-1r II and IL-1ra have been measured in septic patients, although the mechanism is unclear. In this respect, the authors characterize new pathways in which IL-1r II and IL-1ra may be regulated in sepsis through combined stimulation with lipopolysaccharide (LPS) and dexamethasone of peripheral blood mononuclear cells (PBMC). This paper confirms that while dexamethasone induces release of IL-1r II, LPS augments dexamethasone-induced IL-1r II release 45-fold. Furthermore, LPS plus dexamethasone induces IL-1r II protein and mRNA, whereas LPS alone does not. Additionally, it was shown by flow cytometric analysis that the monocyte is the primary IL-1r II producer in response to LPS and dexamethasone administration. Therefore, LPS and dexamethasone synergism in IL-1r II induction may be important in controlling IL-1 beta effects. In contrast, LPS alone induces IL-1ra, while dexamethasone attenuates this LPS-induced response. Although IL-1r II and IL-1ra may work together to suppress IL-1 beta effects in sepsis, inflammatory cells differentially regulate these cytokines.


Subject(s)
Dexamethasone/pharmacology , Glucocorticoids/pharmacology , Interleukin-1/biosynthesis , Receptors, Interleukin-1/biosynthesis , Sialoglycoproteins/biosynthesis , Blotting, Western , Cells, Cultured , Drug Synergism , Flow Cytometry , Humans , Interleukin 1 Receptor Antagonist Protein , Kinetics , Lipopolysaccharides/pharmacology , Monocytes/cytology , Monocytes/drug effects , Monocytes/metabolism , RNA, Messenger/biosynthesis , Receptors, Interleukin-1/antagonists & inhibitors , Receptors, Interleukin-1 Type II
14.
J Immunol ; 157(6): 2632-7, 1996 Sep 15.
Article in English | MEDLINE | ID: mdl-8805667

ABSTRACT

Cross-linking of PBMC and monocyte Fc gamma R on immobilized IgG stimulates IL-8 release. We used immobilized anti-Fc gamma R Abs to determine which of the three surface Fc gamma R regulated this IL-8 secretion. Fc gamma RIII cross-linking stimulated PBMC to release 5 times more IL-8 than did either Fc gamma RI or Fc gamma RII clustering (p = 0.001) and stimulated 77% more IL-8 release from PBMC than that from purified monocytes (p = 0.001). In contrast, only Fc gamma RI cross-linking significantly induced monocytes to release IL-8 (p = 0.05). Since purified lymphocytes release little IL-8 in response to immobilized IgG or anti-Fc gamma RIII Abs, we hypothesized that lymphocyte Fc gamma R cross-linking augmented monocyte IL-8 release. Supernatants from IgG- or Fc gamma RIII -stimulated lymphocytes induced monocytes to release more IL-8 than lymphocytes incubated on plastic alone (p = 0.002 and p = 0.003, respectively). THP-1 cells, which do not produce IL-8 in response to Fc gamma i]R cross-linking, also released IL-8 in response to supernatants from IgG- or Fc gamma RIII-stimulated lymphocytes, suggesting that the supernatant activity was not soluble immune complexes. The IL-8-stimulating activity was heat labile, suggesting that the activity is a protein. However, we could not reproduce or block this activity using recombinant cytokines or neutralizing anti-cytokine Abs. Thus, monocyte IL-8 is stimulated directly through Fc gamma RI cross-linking and indirectly through an Fc gamma RIII-stimulated soluble lymphocyte factor.


Subject(s)
Interleukin-8/metabolism , Monocytes/metabolism , Receptors, IgG/physiology , Cross-Linking Reagents , Humans , Immunoglobulin G/metabolism , Interleukin-8/biosynthesis , Lymphocytes/metabolism , Lymphokines/chemistry , Lymphokines/immunology , Lymphokines/physiology , Monocytes/immunology , Protein Binding/immunology
15.
Clin Chest Med ; 17(2): 183-97, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8792060

ABSTRACT

Gram-negative bacteria gain access to the bloodstream by evading host defenses. Once in circulation, lipopolysaccharide interacts with the host receptor CD14 and initiates the host's immune response. Lipolysaccharide stimulates the host to produce a cascade of mediators that activate and target leukocytes, opsonize the bacteria, and induce fever to defend against the invading bacteria. Unregulated release of these mediators, however, leads to the production of vasoactive substances, activation of the clotting cascade, and diminution of cardiac performance, which leads to the sepsis syndrome. This article discusses the pathogenic events that lead to sepsis syndrome and reviews critical steps in regulating these inflammatory mediators to allow the host to recover from gram-negative bacteremia.


Subject(s)
Cytokines/physiology , Gram-Negative Bacterial Infections/immunology , Systemic Inflammatory Response Syndrome/immunology , Arachidonic Acids/physiology , Humans , Inflammation Mediators/physiology , Lipopolysaccharide Receptors , Lipopolysaccharides
16.
J Immunol ; 156(4): 1594-600, 1996 Feb 15.
Article in English | MEDLINE | ID: mdl-8568265

ABSTRACT

C-reactive protein (CRP), the major acute phase protein in humans, was purified free of endotoxin (LPS) (< 10 pg of LPS/mg of purified CRP) and evaluated for its ability to modulate LPS-induced production of IL-1 beta and IL-1 receptor antagonist (IL-1ra) from human PBMC and lung macrophages. PBMC (5 x 10(6)/ml) released low levels of IL-1 beta in response to either CRP (250 micrograms/ml) or LPS (100 ng/ml) for 18 h (0.3 +/- 0.1 and 1.5 +/- 0.7 ng/ml, respectively). However, when CRP (250 micrograms/ml) and LPS (100 ng/ml) were combined, PBMC released 9.7 +/- 2.9 ng/ml (p < 0.001 vs LPS alone). This synergy was removed by immunodepletion of CRP before stimulation. With respect to IL-1ra, although CRP induced IL-1ra production from PBMC (0.8 +/- 0.3 ng/ml control, 2.6 +/- 1.3 ng/ml with CRP), CRP did not synergize with LPS for IL-1ra production (15.0 +/- 0.7 ng/ml LPS alone vs 15.4 +/- 1.4 ng/ml LPS and CRP). In contrast, lung macrophages responded to CRP quite differently than PBMC. Macrophages (10(6)/ml) were not stimulated to produce IL-1 beta or IL-1ra by CRP alone. When combined with LPS, CRP inhibited IL-1 beta and IL-1ra release induced by LPS (for IL-1 beta release, LPS induced 3.0 +/- 1.7 ng/ml vs 1.1 +/- 0.4 for combined LPS and CRP; for IL-1ra release, LPS induced 12.9 +/- 2.3 ng/ml vs 7.6 +/- 2.3 ng/ml for combined LPS and CRP). These data suggest that acute phase levels of CRP may have divergent effects depending on the target population. CRP may be largely proinflammatory to blood monocytes responding to LPS since IL-1 beta production is augmented over IL-1ra production. However, in tissue compartments the effects of CRP may be largely immunosuppressive to LPS-induced tissue macrophage IL-1 beta production.


Subject(s)
Acute-Phase Reaction , C-Reactive Protein/metabolism , Interleukin-1/biosynthesis , Macrophages, Alveolar/metabolism , Monocytes/metabolism , Sialoglycoproteins/biosynthesis , Adult , Humans , Interleukin 1 Receptor Antagonist Protein , Lipopolysaccharides/pharmacology
17.
J Immunol ; 155(6): 3161-7, 1995 Sep 15.
Article in English | MEDLINE | ID: mdl-7673729

ABSTRACT

In response to bacterial cell wall products such as LPS, monocytes produce IL-8, a powerful neutrophil chemotaxin. However, in the absence of bacterial pathogens, immune complex-mediated diseases such as rheumatoid arthritis are associated with high levels of IL-8 in monocyte-rich compartments. Since it is known that IgG-containing immune complexes can recruit neutrophils via an Fc gamma R-dependent process, we hypothesized that cross-linking of monocyte Fc gamma receptors may induce IL-8. To test this hypothesis, peripheral blood mononuclear cells were evaluated for IL-8 induction in response to immobilized LPS-free pooled human IgG. Immobilized IgG, but not soluble IgG, induced IL-8 in a dose-dependent manner (p < 0.05, r = 0.99). This induction corresponded with an up-regulation in IL-8 steady state mRNA levels that peaked at 4 h. The released IL-8 was functional, since supernatants induced concentration-dependent neutrophil migration that was inhibited by a monoclonal anti-IL-8 Ab. Evaluation of purified monocytes for IL-8 production, as well as FACS analysis of IgG-stimulated PBMC preparations, demonstrated that monocytes are the principal IL-8 producer cell. Thus, monocyte Fc gamma R cross-linking induces biologically active IL-8, which may participate in the pathogenesis of immune complex-mediated diseases.


Subject(s)
Immunoglobulin G/pharmacology , Interleukin-8/biosynthesis , Monocytes/immunology , Receptors, IgG/immunology , Cells, Cultured , Dose-Response Relationship, Drug , Humans , Immunoglobulin G/immunology , Lipopolysaccharides/pharmacology
18.
J Lab Clin Med ; 125(3): 356-69, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7897303

ABSTRACT

Alveolar macrophages have been shown to be major producers of the potent proinflammatory cytokines interleukin-1 beta and tumor necrosis factor-alpha, and of the antiinflammatory cytokine interleukin-1 receptor antagonist. During the adult respiratory distress syndrome the normally surfactant-coated alveolus becomes flooded with plasma proteins, altering the milieu of alveolar cells such as alveolar macrophages. To understand alveolar macrophage function during the adult respiratory distress syndrome, the individual and combined effects of surfactant and plasma on alveolar macrophage cytokine production was examined. A synthetic surfactant (Exosurf) and a bovine-derived surfactant (Survanta) both inhibited production of interleukin-1 beta, pro-interleukin-1 beta, tumor necrosis factor-alpha, and interleukin-1 receptor antagonist in a dose-dependent manner. This inhibition was noted when both endotoxin and heat-killed Staphylococcus aureus were used as stimuli. Autologous plasma also inhibited interleukin-1 beta and tumor necrosis factor-alpha release in a dose-dependent manner, but, unlike surfactant, plasma did not inhibit interleukin-1 receptor antagonist release. Similarly, the combination of plasma and surfactant inhibited interleukin-1 beta and tumor necrosis factor-alpha release but not interleukin-1 receptor antagonist release. In support of these data, interleukin-1 receptor antagonist was detectable in five of six bronchoalveolar lavage fluid samples from patients with adult respiratory distress syndrome at a mean concentration of 465 pg/ml; on the other hand, interleukin-1 beta was not detectable in any of these samples. These results indicate that the relative production of interleukin-1 beta, tumor necrosis factor-alpha, and interleukin-1 receptor antagonist can be altered depending on the local concentration of both surfactant and plasma.


Subject(s)
Biological Products , Immune Tolerance , Macrophages, Alveolar/physiology , Phosphorylcholine , Plasma/physiology , Pulmonary Surfactants/physiology , Bronchoalveolar Lavage Fluid/chemistry , Drug Combinations , Enzyme-Linked Immunosorbent Assay , Fatty Alcohols/pharmacology , Female , Humans , Interleukin-1/antagonists & inhibitors , Interleukin-1/biosynthesis , Lipopolysaccharides/pharmacology , Male , Polyethylene Glycols/pharmacology , Protein Precursors/antagonists & inhibitors , Pulmonary Surfactants/pharmacology , Receptors, Interleukin-1/antagonists & inhibitors , Respiratory Distress Syndrome/metabolism , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Tumor Necrosis Factor-alpha/biosynthesis
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