ABSTRACT
BACKGROUND: Drug addiction causes chronic wounds (CW) responsible for severe complications. Very few studies are available on this topic. The aim of our study was to describe the demographic, clinical and etiological characteristics as well as the course of CW in drug addicts. PATIENTS AND METHODS: This was a retrospective and prospective multicenter study including all drug addicts with CW. RESULTS: We included 58 patients (17 prospectively), 84.5% of whom were male, of median age 43 years, presenting multiple CW as a result of intravenous (78.2%), inhaled (41.1%) and/or snorted (20%) drug abuse. Addiction to opioids (68.4%), cocaine (47.4%) and/or cannabis (40.4%) was ended and/or treated through substitution in 79.3% of patients. CW were fibrinous and necrotic (42.9 to 53.6%), recurrent (54.2%), and in some cases had been present for more than 1 year (61.5%). Intravenous drug addiction was associated with large, fibrinous, ulcers in a setting of venous and lymphatic insufficiency (74%). Only 23% of these wounds involved the upper limbs. Necrotic ulcers associated with clinical arteriopathy were described mainly with inhaled addiction. Abscesses (50%) and erysipelas (29.3%) were the most common cutaneous complications. After 3 months, 50% of CW were improved and 29.2% of patients were lost to follow-up. DISCUSSION: Drug abuse-related CW occurred preferentially in young men with history of intravenous abuse. For the most part, CW were seen on the legs and were associated with venous and lymphatic insufficiency, and the resulting major risk for cutaneous infection increased morbidity and mortality in this population in whom medical follow-up is inherently complicated.
Subject(s)
Abscess/etiology , Erysipelas/etiology , Skin Ulcer/etiology , Substance-Related Disorders/complications , Adult , Chronic Disease , Female , Humans , Male , Middle Aged , Prospective Studies , Retrospective Studies , Venous Insufficiency/etiologySubject(s)
Pyoderma Gangrenosum/epidemiology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Child , Comorbidity , Diabetes Mellitus/epidemiology , Female , France/epidemiology , Hematologic Diseases/epidemiology , Humans , Hypertension/epidemiology , Inflammatory Bowel Diseases/epidemiology , Male , Middle Aged , Retrospective Studies , Rheumatic Diseases/epidemiology , Young AdultABSTRACT
Triketones, derived chemically from a natural phytotoxin (leptospermone), are a good example of allelochemicals as lead molecules for the development of new herbicides. Targeting a new and key enzyme involved in carotenoid biosynthesis, these latest-generation herbicides (sulcotrione, mesotrione and tembotrione) were designed to be eco-friendly and commercialized fifteen-twenty years ago. The mechanisms controlling their fate in different ecological niches as well as their toxicity and impact on different organisms or ecosystems are still under investigation. This review combines an overview of the results published in the literature on ß-triketones and more specifically, on the commercially-available herbicides and includes new results obtained in our interdisciplinary study aiming to understand all the processes involved (i) in their transfer from the soil to the connected aquatic compartments, (ii) in their transformation by photochemical and biological mechanisms but also to evaluate (iii) the impacts of the parent molecules and their transformation products on various target and non-target organisms (aquatic microorganisms, plants, soil microbial communities). Analysis of all the data on the fate and impact of these molecules, used pure, as formulation or in cocktails, give an overall guide for the assessment of their environmental risks.
Subject(s)
Herbicides/analysis , Herbicides/chemistry , Ketones/analysis , Ketones/chemistry , Cyclohexanones/analysis , Ecosystem , Ecotoxicology , Environment , Hydrogen-Ion Concentration , Mesylates/analysis , Photochemistry , Plants/drug effects , Risk Assessment , Soil , Soil Microbiology , Sulfones/analysis , Temperature , Water , Water Pollutants, Chemical/chemistryABSTRACT
BACKGROUND: Anti-p200 pemphigoid is a rare autoimmune blistering disease (AIBD) of the dermoepidermal junction, characterized by autoantibodies to laminin γ1. The clinical course of anti-p200 pemphigoid in patients remains poorly investigated. OBJECTIVES: We aimed to describe the clinical and immunological features and the course of a series of patients with anti-p200 pemphigoid. METHODS: We conducted a retrospective study by immunoblotting detection of sera on 200-kDa dermal protein extracts from the register of the French reference centre for AIBD. We recorded the clinical and immunological features and the course of patients. RESULTS: A total of 14 patients with a mean age 81·6 ± 6·5 years were included. Only one patient had an associated neurological condition and one had psoriasis. Twelve patients had atypical clinical presentation, including eczematous, urticarial, prurigo-like, dyshydrosis-like and rosette-like skin lesions. Eight patients (57%) had mucosal involvement. Immunoblot analysis of sera on dermal and epidermal extracts showed a 200-kDa band in 14 and 10 cases, respectively. All eight of the sera tested by enzyme-linked immunosorbent assay detected recombinant human laminin γ1. Disease control was obtained in six of nine patients treated with topical corticosteroids, and four of five patients who received systemic treatment. Seven patients relapsed (50%) and five patients (36%) died during the median follow-up time of 12·6 months. At the end of the study, only one of the nine living patients was in complete remission off therapy. CONCLUSIONS: Many patients with anti-p200 pemphigoid had heterogeneous clinical presentation and a more severe prognosis than previously suspected.
Subject(s)
Laminin/immunology , Pemphigoid, Bullous/pathology , Aged , Aged, 80 and over , Dermatologic Agents/therapeutic use , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Pemphigoid, Bullous/drug therapy , Pemphigoid, Bullous/immunology , Prognosis , Recurrence , Retrospective StudiesABSTRACT
AIM: The aim of our study was to evaluate the use of Teissier's spatulas in preterm vaginal deliveries by comparing them to spontaneous deliveries. MATERIALS AND METHODS: A retrospective monocentric case-control study was conducted from 2008 to 2012 on single cephalic presentations with live births between 28 and 34weeks of gestation. A comparison was made between spontaneous vaginal (controls) and instrumental deliveries by Teissier's spatulas (cases) on maternal, obstetrical and neonatal outcomes. RESULTS: The spatulas and Vaginal Spontaneous Delivery (VSD) groups were constituted of 94 and 86 patients respectively. Occiput posterior presentations were increased in the spatulas group (11.7% vs. 1.2%, P=0.003) whereas the difference in the rate of third/fourth degree perineal tear was not significant (1% vs 0%, P=1) without the need for any episiotomy. No significant difference between spatulas and VSD groups was observed in terms of Apgar score at 5minutes (P=0.61) and 10minutes (P=0.37), mean umbilical arterial pH (7.26 vs 7.3, P=0.13), transfer to ICU (56.4% vs. 65.1%, P=0.18), length of stay in ICU (5.1 versus 4.0days, P=0.19), the need for invasive ventilation (15.9% vs 19.7%, P=0.17), and the rate of intraventricular hemorrhage (4.3% versus 5.8%, P=0.39). CONCLUSION: Instrumental deliveries by Teissier's spatulas for preterm fetuses are not accompanied by any increase in neonatal or maternal morbidity.
Subject(s)
Delivery, Obstetric/statistics & numerical data , Extraction, Obstetrical/statistics & numerical data , Pregnancy Outcome/epidemiology , Premature Birth/epidemiology , Surgical Instruments/statistics & numerical data , Adult , Female , Humans , Pregnancy , Retrospective StudiesABSTRACT
Grape marc extract (GME) showed elicitor activity on suspension-cultured cells of tobacco. The BY-2 cells reacted to GME (0.25% and 0.125%) with a long-sustained pH rise in their growth medium. Using EGTA or LaCl3, we showed that extracellular alkalinization depended on Ca(2+) mobilization. The tobacco BY-2 cells challenged with GME promoted cell death and the upregulation of defence-related genes such as PR3, PAL and CCoAOMT. Cell death rate was quantified using an experimental calibrated Evans Blue assay. The GME-induced cell death was dose-dependent and occurred in 24 h. Longer exposure increased the extent of tobacco cell death. To investigate a potential hypersensitive reaction, we tested the effect of various inhibitors of protein synthesis (cycloheximide) and proteases (aprotinin, pepstatin and E-64) on GME-induced cell death. All these chemicals reduced GME-induced cell death rate in 30 min. Overall, our findings indicate that GME elicits early perception events, defence reactions and cell death requiring protein synthesis and proteases.
Subject(s)
Cell Death , Disease Resistance , Genes, Plant , Nicotiana/drug effects , Plant Diseases , Plant Extracts/pharmacology , Vitis , Aprotinin/pharmacology , Cells, Cultured , Cycloheximide/pharmacology , Disease Resistance/genetics , Hydrogen-Ion Concentration , Leucine/analogs & derivatives , Leucine/pharmacology , Pepstatins/pharmacology , Peptide Hydrolases/metabolism , Plant Proteins/metabolism , Nicotiana/genetics , Nicotiana/metabolism , Up-RegulationABSTRACT
BACKGROUND: Our aim was to evaluate the efficacy of total skin electron beam therapy (TSEB) in the management of early-stage mycosis fungoides in order to assess its position in relation to other skin-directed therapies. PATIENTS AND METHODS: A retrospective study of 68 patients (30 in stage T1 and 38 in stage T2). RESULTS: The median treatment duration was 6 weeks. Three months after the end of TSEB, a complete clinical response occurred in 66 patients (97%). The most marked effects of acute toxicity included localized ulcerations in 13 patients (13.2%) not requiring hospitalization. Mean follow-up was 6.5 years (1.6 to 28.7). The overall survival rates at 5 and 10 years were 86% and 71%, respectively. Thirty-nine patients (57.4%) experienced relapse with a mean disease-free interval of 1.8 years. The disease-free survival rates at 5 and 10 years were 41% and 31%, respectively. This rate was higher when TSEB was performed early (p=0.031). Twenty-one years after TSEB, only one case of cutaneous malignancy (basal cell carcinoma) was noted. DISCUSSION: Because of its high response rates and rapidity of action, TSEB should be considered as first-line therapy in the management of early-stage mycosis fungoides.
Subject(s)
Electrons/therapeutic use , Mycosis Fungoides/radiotherapy , Skin Neoplasms/radiotherapy , Electrons/adverse effects , Female , Follow-Up Studies , Humans , Male , Middle Aged , Mycosis Fungoides/mortality , Mycosis Fungoides/pathology , Neoplasm Staging , Retrospective Studies , Skin Neoplasms/mortality , Skin Neoplasms/pathology , Skin Ulcer/etiology , Survival Analysis , Survivors , Treatment OutcomeABSTRACT
BACKGROUND: Patent blue is a blue dye commonly used for sentinel node detection in the management of melanoma and breast cancer. Immediate hypersensitivity reactions to patent blue such as blue urticaria, bronchospasm or anaphylactic shock are not rare, being seen in 0.8 to 2.8% of patent blue-treated patients. PATIENTS AND METHODS: We report three cases of anaphylactic shock and two cases of urticaria developed after injection of patent blue in the context of sentinel node detection in breast cancer patients. Immediately after surgery, two patients developed generalized urticaria followed by circulatory collapse requiring resuscitation. The third patient presented massive anaphylactic shock without cutaneous or respiratory signs. Blue urticaria without haemodynamic disturbance was seen in the latter two patients. Prick tests using patent blue were positive for the three patients with positive intradermal reactions (1/10,000 dilution) in all patients. DISCUSSION: These observations underline the severity of patent blue-induced shocks with delayed onset, since they are often observed at the end of surgery. While the mode of sensitization is poorly understood, food and textile dyes are thought to play a role. Skin prick tests provide a simple and reliable method of diagnosing these events. There is a real risk of late anaphylactic shock during sentinel node detection using patent blue and discussion is needed concerning alternative methods of sentinel node detection.
Subject(s)
Breast Neoplasms/surgery , Hypersensitivity, Immediate/chemically induced , Rosaniline Dyes/adverse effects , Sentinel Lymph Node Biopsy/methods , Anaphylaxis/chemically induced , Breast Neoplasms/pathology , Female , Humans , Hypersensitivity, Immediate/diagnosis , Methylene Blue/adverse effects , Middle Aged , Skin Tests , Time Factors , Urticaria/chemically inducedABSTRACT
In the immune system, interleukin (IL)-1 beta effects are mediated by the type I IL-1 receptors (IL-1RI), whereas the type II IL-1 receptors (IL-1RII) act as inhibitory receptors. IL-1RI and IL-1RII are also present in the brain. To study their functionality in the brain, mice were centrally treated with neutralizing monoclonal antibody (MAb) directed against IL-1RI (35F5, 1 microgram) or against IL-1RII (4E2, 2 micrograms) and were centrally injected with recombinant rat IL-1 beta at a dose (2 ng) that decreased social exploration. Only 35F5 was effective in abrogating the behavioral effect of IL-1 beta. Moreover, 4E2 (1 microgram i.c.v.) did not potentiate the behavioral response to a subthreshold dose of IL-1 beta (1 ng i.c.v.). To examine the ability of brain IL-1RI to mediate the effects of endogenous IL-1 beta, mice were centrally treated with 35F5 (4 micrograms) and peripherally injected with IL-1 beta (1 microgram). Like IL-1 receptor antagonist (4 micrograms i.c.v.), 35F5 abrogated the effects of IL-1 beta. These results suggest that brain IL-1RI mediates the behavioral effects of IL-1 beta in mice.
Subject(s)
Behavior, Animal/physiology , Brain/physiology , Receptors, Interleukin-1/physiology , Social Behavior , Animals , Antibodies, Monoclonal , Immunologic Techniques , Injections, Intraventricular , Interleukin 1 Receptor Antagonist Protein , Male , Mice , Receptors, Interleukin-1 Type I , Receptors, Interleukin-1 Type II , Sialoglycoproteins/administration & dosageABSTRACT
The proinflammatory cytokines which are released by activated accessory immune cells during the course of an infection have profound effects on the brain. These effects include activation of the hypothalamic-pituitary-adrenal axis, fever and behavioral depression. They are mediated by cytokines which are synthesized and released in the brain, in response to peripherally released cytokines. Glucocorticoids have potent regulatory effects on the synthesis of cytokines by activated macrophages and monocytes. These hormones are also able to regulate the synthesis and action of cytokines in the brain, as demonstrated by the sensitizing effects of adrenalectomy and the depressing effects of stress on the increased cytokine and interleukin-1 beta converting enzyme gene expression that occurs in response to lipopolysaccharide in mice. Preliminary experiments indicate that another way glucocorticoids can contribute to down regulation of the IL-1 system is by increasing the expression of the type II IL-1 receptor in the brain. The regulatory effects of glucocorticoids on cytokine expression in the brain have functional consequences, as demonstrated by the enhanced sensitivity of adrenalectomized animals to the behavioral actions of centrally administered LPS and IL-1. The effects of adrenalectomy are inhibited by compensation with a corticosterone implant and they are mimicked by administration of the type II glucocorticoid receptor, RU 38486. The regulatory role of glucocorticoids on the expression and action of cytokines in the brain makes these hormones and their mechanisms of action key targets for therapeutic interventions in psychopathology and neuropathology.
Subject(s)
Central Nervous System/physiology , Cytokines/biosynthesis , Cytokines/genetics , Glucocorticoids/pharmacology , Animals , Central Nervous System/drug effects , HumansABSTRACT
The present study was carried out to determine whether those factors which regulate the expression of IL-1 beta in immune and non-immune tissues are also able to regulate the expression of ICE. In a first experiment, mice were injected with LPS (10 micrograms/mouse, i.p.) and killed before, 1, 3 or 6 h after the injection. Total RNAs were extracted from the spleen, pituitary and brain (hippocampus and hypothalamus) and submitted to RT-PCR to determine the levels of ICE mRNA as compared to beta 2 microglobulin mRNA. ICE mRNAs were more abundant in the spleen and hippocampus than in the pituitary and hypothalamus but they were not significantly altered by LPS treatment. In a second experiment mice were submitted to adrenalectomy or a 15 min restraint stress and injected with saline or LPS (10 micrograms/mouse. sc). They were killed 1-2 h later and total RNA was extracted from the same tissues as in experiment 1. Adrenalectomized mice had significantly higher ICE mRNA levels whereas stressed mice had significantly lower ICE mRNA levels than their respective controls. These results are discussed with respect to the possible regulatory influence of glucocorticoids on the expression of ICE.
Subject(s)
Brain/enzymology , Brain/physiology , Cysteine Endopeptidases/drug effects , Cysteine Endopeptidases/genetics , Glucocorticoids/immunology , Lipopolysaccharides/pharmacology , Pituitary Gland/enzymology , Pituitary Gland/physiology , Adrenalectomy , Animals , Brain Chemistry/drug effects , Brain Chemistry/immunology , Caspase 1 , Corticosterone/blood , Gene Expression/drug effects , Gene Expression/immunology , Male , Mice , Mice, Inbred ICR , Polymerase Chain Reaction , RNA, Messenger/analysis , Spleen/physiology , Stress, Physiological/immunology , Stress, Physiological/physiopathologyABSTRACT
To assess the possible influence of endogenous glucocorticoids on cytokine expression in the brain, adrenalectomized mice and sham operated mice were injected with saline or lipopolysaccharide (LPS, 10 micrograms/mouse, subcutaneously) and the levels of transcripts for IL-1 alpha, IL-1 beta, IL-1ra, IL-6 and tumor necrosis factor-alpha (TNF alpha) were determined 2 h after treatment in the spleen, pituitary, hypothalamus, hippocampus and striatum, using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). Levels of IL-1 beta were measured by ELISA in plasma and tissues of mice sacrificed after the administration of LPS or saline. LPS induced the expression of pro-inflammatory cytokines at the mRNA level in all tissues under investigation, except for TNF alpha in the hippocampus. This effect was potentiated by adrenalectomy in the spleen for IL-1 alpha and IL-1ra, the pituitary for cytokines other than IL-1ra, the hypothalamus for all cytokines, the hippocampus for cytokines other than TNF alpha, and the striatum for IL-1 alpha and IL-6. In saline-treated mice, adrenalectomy increased IL-1 alpha and IL-1 beta gene expression in the hypothalamus and IL-1 alpha gene expression in the hippocampus and striatum. LPS increased plasma and tissue levels of IL-1 beta, as determined by ELISA, and this effect was potentiated by adrenalectomy in plasma and tissues other than the spleen. These results can be interpreted to suggest that endogenous glucocorticoids regulate the neural components of the host response to infection and inflammation by inhibiting cytokine expression in peripheral organs and the brain.
Subject(s)
Adrenal Glands/physiology , Brain/drug effects , Cytokines/genetics , Gene Expression Regulation/drug effects , Pituitary Gland/drug effects , Spleen/drug effects , Adrenalectomy , Animals , Base Sequence , Brain/metabolism , Corticosterone/blood , Inflammation/metabolism , Interleukins/genetics , Lipopolysaccharides/pharmacology , Male , Mice , Mice, Inbred ICR , Molecular Sequence Data , Pituitary Gland/metabolism , Spleen/metabolism , Tumor Necrosis Factor-alpha/geneticsABSTRACT
Mice injected with LPS (10 mu g/mouse, sc) or saline were submitted to a 15-min restraint stress and sacrificed 1 or 2 h later to assess the effect of stress on the induction of interleukin-1beta (IL-1beta) and other proinflammatory cytokines (IL-1alpha, IL-1ra, IL-6, and tumor necrosis factor-alpha) in the spleen, pituitary, hypothalamus, hippocampus, and striatum. LPS-induced cytokine gene expression, as determined by comparative RT-PCR, was lower in stressed than in nonstressed mice. LPS increased plasma and tissue levels of IL-1beta, as determined by ELISA, but this effect was less marked in stressed than in nonstressed mice. These results are discussed in relation to the modulatory effects of glucocorticoids on cytokine production.
Subject(s)
Brain/metabolism , Gene Expression Regulation , Interleukin-1/biosynthesis , Interleukin-6/biosynthesis , Lipopolysaccharides/pharmacology , Neuroimmunomodulation/physiology , Pituitary Gland/metabolism , Spleen/metabolism , Stress, Physiological/physiopathology , Tumor Necrosis Factor-alpha/biosynthesis , Animals , Brain/drug effects , Corpus Striatum/drug effects , Corpus Striatum/metabolism , Corticosterone/blood , Gene Expression Regulation/drug effects , Hippocampus/drug effects , Hippocampus/metabolism , Hypothalamus/drug effects , Hypothalamus/metabolism , Interleukin 1 Receptor Antagonist Protein , Interleukin-1/genetics , Interleukin-6/genetics , Male , Mice , Mice, Inbred ICR , Neuroimmunomodulation/drug effects , Pituitary Gland/drug effects , RNA, Messenger/analysis , Restraint, Physical , Sialoglycoproteins/biosynthesis , Sialoglycoproteins/genetics , Spleen/drug effects , Tumor Necrosis Factor-alpha/geneticsABSTRACT
Adrenalectomy sensitizes laboratory animals to the pyrogenic and behavioural effects of proinflammatory cytokines. To determine whether these effects are mediated by central sites of action of glucocorticoids, interleukin-1 beta was injected intracerebroventricularly (i.c.v.) in adrenalectomized mice with or without corticosterone supplementation and in mice pretreated i.c.v. with the glucocorticoid type II receptor antagonist RU38486. Adrenalectomized mice were more sensitive to the depressing effects of i.c.v. IL-1 beta on body temperature and social exploration than sham-operated mice. Corticosterone supplementation reversed the increased sensitivity to the low (300 pg/mouse) but not to the high dose (900 pg/mouse) of IL-1 beta. Central administration of RU38486 (0.5-1 microgram/mouse) mimicked the effects of adrenalectomy on behaviour but not on body temperature. These results suggest that endogenous glucocorticoids released in response to IL-1 beta act in the brain to modulate the sensitivity of the cellular targets of this cytokine.
Subject(s)
Behavior, Animal/drug effects , Body Temperature/drug effects , Glucocorticoids/pharmacology , Interleukin-1/pharmacology , Animals , Dose-Response Relationship, Drug , Down-Regulation , Male , Mice , Mice, Inbred Strains , Mifepristone/pharmacology , Time FactorsABSTRACT
The modulatory role of endogenous corticoids in the behavioral effects of lipopolysaccharide (LPS) and recombinant human interleukin-1 beta (IL-1 beta) was studied in mice. Adrenalectomy enhanced the depression of social exploration induced by subcutaneous injection of 200 ng of IL-1 beta or 2 micrograms of LPS. This effect was mimicked by an acute injection of the progesterone antagonist RU-38486 (0.25-1 mg). Chronic replacement with a 15-mg corticosterone pellet abrogated the enhanced susceptibility of adrenalectomized animals to 200 ng of IL-1 beta but had only partial protective effects on their response to 400 ng of IL-1 beta and LPS. These results suggest that the pituitary-adrenal response to cytokines exerts an inhibitory feedback on the cell targets that mediate the behavioral effects of LPS and IL-1 beta.
Subject(s)
Behavior, Animal/drug effects , Corticosterone/pharmacology , Interleukin-1/pharmacology , Lipopolysaccharides/pharmacology , Adrenalectomy , Animals , Corticosterone/blood , Dose-Response Relationship, Drug , Humans , Male , Mice , Mice, Inbred ICR , Mifepristone/pharmacology , Organ Size/drug effects , Recombinant Proteins , Social Behavior , Thymus Gland/anatomy & histologyABSTRACT
The reverse transcription polymerase chain reaction (RT-PCR) was used to assess the induction of mRNA of the proinflammatory cytokines IL-1 beta, IL-6 and TNF alpha in the spleen, pituitary, hypothalamus and hippocampus of mice after an intraperitoneal injection of lipopolysaccharide (LPS, 10 micrograms/mouse). The kinetics of cytokine gene expression induced by peripheral LPS in the pituitary and brain structures were different from that observed in the spleen. For IL-1 beta the dose-response curve was also measured and also found to be different. These results support the idea that one pathway by which peripheral immune stimuli affect brain functions includes local synthesis of proinflammatory cytokines in certain brain structures.
Subject(s)
Brain/drug effects , Gene Expression Regulation/drug effects , Interleukin-1/biosynthesis , Interleukin-6/biosynthesis , Lipopolysaccharides/pharmacology , Pituitary Gland/drug effects , Tumor Necrosis Factor-alpha/biosynthesis , Animals , Base Sequence , Brain/metabolism , Dose-Response Relationship, Drug , Hippocampus/drug effects , Hippocampus/metabolism , Hypothalamus/drug effects , Hypothalamus/metabolism , Inflammation , Interleukin-1/genetics , Interleukin-6/genetics , Kinetics , Male , Mice , Molecular Sequence Data , Nerve Tissue Proteins/biosynthesis , Nerve Tissue Proteins/genetics , Pituitary Gland/metabolism , Spleen/drug effects , Spleen/metabolism , Tumor Necrosis Factor-alpha/genetics , beta 2-Microglobulin/biosynthesis , beta 2-Microglobulin/geneticsABSTRACT
Although binding sites for IL-1 have been identified in the mouse brain, it is still unknown whether these binding sites correspond to the type I or type II IL-1 receptor. Quantitative autoradiography was used to confirm the presence of specific binding sites for radiolabelled recombinant human IL-1 alpha (125I-HuIL-1 alpha) in the brain of DBA/2 mice. IL-1 binding was highest in the dentate gyrus, consisting of a single class of high affinity binding sites with a Kd of 0.1 nM and a Bmax of 57 fmol/mg protein. A similar Kd of 0.2 nM was obtained using isolated membranes from the whole hippocampus, although the number of binding sites was lower (2 fmol/mg protein). Affinity cross-linking of 125I-Hu-IL-1 alpha to hippocampal membranes revealed the existence of two types of IL-1 receptor proteins, consistent with the sizes of the type I (85 kD) and type II (60 kD) IL-1 receptor. Oligonucleotide probes were then synthesized and used in RT-PCR followed by Southern blotting to show that the whole brain expresses transcripts for both the type I and type II IL-1 receptors. The murine neuroblastoma cell line, C1300, expresses type I rather than type II IL-1 receptor mRNA. The type I receptor protein can be identified by flow cytometry on the membrane of the C1300 neuronal cell line using indirect immunofluorescence with a rat anti-mouse type I IL-1 receptor MoAb. These data show that mouse brain expresses both type I and type II IL-1 receptor mRNA and proteins and offer further support to the idea that type I IL-1 receptors are synthesized and expressed by neurons.