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D Emilie

Publications and source records attributed to D Emilie.

At least 91 records · Page 5Linked to original sources
PubMed1995

Regulation of the production of the RANTES chemokine by endothelial cells. Synergistic induction by IFN-gamma plus TNF-alpha and inhibition by IL-4 and IL-13.

Production by endothelial cells of the regulated on activation normal T expressed and secreted chemokine (RANTES) has recently been evidenced during delayed-type hypersensitivity (DTH) reactions and may contribute to the local accumulation of macrophages and CD4+ memory T lymphocytes. To document the mechanism inducing RANTES production in this condition, we analyzed the effect of cytokines known to influence the formation of DTH granulomas. Little or no RANTES was produced after stimulation of HUVEC with IFN-gamma, IL-1 beta, or TNF-alpha. However, the combination TNF-alpha+IFN-gamma induced a strong RANTES production. In situ hybridization experiments with a RANTES probe showed that this synergy was also observed at the mRNA level and that the effect of the combination was mainly to increase the amount of RANTES mRNA per cell. The expression of the luciferase gene under the control of the RANTES gene regulatory elements was analyzed; TNF-alpha and the combination TNF-alpha+IFN-gamma activated the regulatory elements. Sequential treatment of HUVEC with TNF-alpha and IFN-gamma showed that IFN-gamma sensitized HUVEC to the stimulating effect of TNF-alpha. The production of RANTES induced by TNF-alpha+IFN-gamma was partly but significantly inhibited by the Th2-type cytokines IL-4 and IL-13. In contrast, IL-10 had no effect. These results indicate that the microenvironment of DTH granulomas, containing high levels of both TNF-alpha and IFN-gamma, may be responsible for RANTES production by perigranulomatous endothelial cells. Inhibition of this production by Th2-type cytokines may be a mechanism by which these cytokines interfere with the formation of DTH granulomas.

Chemokine CCL5↗
PubMed1995

Intratumoral activation of CD8-positive cytotoxic lymphocytes in acquired immunodeficiency syndrome lymphomas.

The incidence of lymphomas is unusually high in human immunodeficiency virus (HIV)-infected patients. Because cytotoxic T lymphocytes (CTL) represent a major mechanism of the antitumoral immune response in immunocompetent individuals, we asked whether intratumoral activation of CTL was impaired in acquired immune deficiency syndrome (AIDS) lymphomas. Immunohistochemical experiments showed that in AIDS lymphomas intratumoral CD8-positive T lymphocytes accumulated and expressed the TIA-1 antigen, a marker of cytotoxic cells. Flow cytometry studies and in situ hybridization of lymphomatous tissue confirmed the differentiation of CD8-positive cells in cytotoxic cells and their activation, as assessed by their expression of CD38 and human leukocyte antigen (HLA) DR markers as well as the perforin and granzyme B genes, which code for two molecules involved in target cell killing. On average, perforin-producing cells were as numerous in AIDS lymphomas (5,647 +/- 2,655 cells/cm2) as in lymphomas from immunocompetent individuals (3,294 +/- 1,544 cells/cm2). The density of activated CD8-positive cells in the 22 AIDS lymphomas tested was not correlated with peripheral CD4-positive cell counts. These results suggest that in AIDS lymphomas the steps of differentiation and activation of cytotoxic CD8-positive cells are not altered by immune deficiency and that they can take place through pathways relatively independent of CD4-positive T lymphocytes. Thus, other mechanisms of immune deficiency should account for the increased frequency of lymphomas in patients with AIDS.

Adult↗
PubMed1995

Macrophage and granulosa interleukin-1 beta mRNA in human ovulatory follicles.

Interleukin-1 beta (IL-1 beta) may be active in the ovary at ovulation and may be produced by immune and non-immune cells. This study evaluates the production of IL-1 beta by granulosa cells and macrophages from the human ovulatory follicle. The concentrations of IL-1 beta and IL-1 beta mRNA were measured in follicular aspirates taken from patients undergoing in-vitro fertilization and in cultures of cells from aspirates. Macrophages were detected by immunocytochemistry and by the reverse transcriptase polymerase chain reaction (RT-PCR). The macrophages were removed from granulosa cell preparations immediately or after the cells have been cultured for 24 h. IL-1 beta was detected by radioimmunoassay and transcripts were detected by RT-PCR and by in-situ hybridization on cytospun preparations using a [35S]IL-1 beta riboprobe. IL-1 beta and IL-1 beta mRNA were found in follicular aspirates, in granulosa luteal cell preparations containing macrophages and in highly purified granulosa cell preparations after removal of macrophages by all the methods used. Both macrophages and granulosa cells contained high concentrations of IL-1 beta transcripts. Moreover, the number of IL-1 beta reactive cells in granulosa cell preparations cultured for 24 h with 10-15% macrophages before removal was twice that of granulosa cells cultured without macrophages. Thus, both granulosa cells and macrophages are actively involved in the ovarian production of IL-1 beta at ovulation and the ability of granulosa cells to produce IL-1 beta may require ovarian macrophages.

Adult↗
PubMed1995

Interleukin-6 and interleukin-1 beta production in a pediatric plasma cell granuloma of the lung.

Plasma cell granuloma (PCG) is a pseudotumor of unknown origin. It is frequently accompanied by acute-phase clinical and biological signs that resume after complete surgical removal, suggesting production of soluble mediators. We therefore investigated the role of cytokines in a previously healthy 10-year-old boy with a PCG of the lung and systemic symptoms. In this case, very high serum levels of interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) were found before tumor excision, associated with inflammatory signs including major hyper-gamma-globulinemia. Pathologic analysis of the tumor showed an accumulation of fibroblasts and plasma cells producing immunoglobulins. Local production of IL-1 beta and IL-6 could be demonstrated at the messenger RNA (mRNA) level by the reverse transcriptase polymerase chain reaction and could be attributed to inflammatory cells by in situ hybridization and immunohistochemistry, whereas plasma cells exhibited membrane expression of the IL-6 receptor. Postsurgery follow-up showed rapid normalization of serum IL-1 beta and IL-6, whereas inflammatory protein levels decreased. This confirms the local production of cytokine within the PCG and raises the question of whether a dysregulation of cytokine production initiates the disease.

Base Sequence↗
PubMed1995

Increased interleukin-1 and interleukin-6 serum concentrations in severe primary pulmonary hypertension.

Primary pulmonary hypertension (PPH) is characterized by the proliferation of smooth-muscle cells, fibroblasts, and endothelial cells in the walls of small pulmonary arteries. In order to evaluate a role for proinflammatory cytokines in this process, we studied the concentration of interleukin-1 beta (IL-1 beta), IL-6, and tumor necrosis factor-alpha (TNF alpha) in the serum of 29 patients with severe PPH referred to our center for lung transplantation. Results were compared with those obtained in 15 normal controls and nine patients with pulmonary hypertension secondary to chronic obstructive pulmonary disease (COPD-PH). TNF alpha serum levels were within the normal range in each group. This contrasted with increased IL-1 beta serum levels in severe PPH (118 +/- 36 pg/ml, mean +/- SEM) as compared with controls (3 +/- 1 pg/ml, p < 0.001) or COPD-PH patients (3 +/- 1 pg/ml, p < 0.001). IL-6 serum concentrations were also higher in severe PPH (66 +/- 20 pg/ml) than in controls (14 +/- 6 pg/ml, p < 0.01). This study demonstrates increased serum levels of IL-1 beta and IL-6 in severe PPH, and suggests a role for proinflammatory cytokines in PPH.

Adult↗
PubMed1995

Ovarian production of IL6 and its potential inhibitory effect on progesterone secretion in Cynomolgus fascicularis.

We explored the potential relevance of interleukin-6 (IL6) to ovarian function in cynomolgus monkey females which were treated to induce multiple follicular growth. Present work gave evidences that IL6 was produced in the ovulatory follicle after hCG administration by using anti-IL6 monoclonal antibody and immunohistochemical techniques. IL6 was produced by granulosa cells in cultures. However, this production was not stimulated by adding to cultures FSH or Bt2cAMP, known to induce IL6 production in various cell types. IL6 was shown to antagonize luteinizing FSH effects. Inhibitory IL6 effect was probably mediated at a site distal to cAMP generation since it had no effect on progesterone production induced by dibutyryl cAMP treatment. The presence of IL6 in the ovulatory follicle show that inflammatory cytokines may play a role at ovulation. On the other hand, its inhibitory effect on progesterone production by granulosa cells could not likely affect the process of luteinization which is controlled by LH/hCG.

Animals↗
PubMed1994

Administration of an anti-interleukin-6 monoclonal antibody to patients with acquired immunodeficiency syndrome and lymphoma: effect on lymphoma growth and on B clinical symptoms.

Increased interleukin-6 (IL-6) production and expression by malignant cells of the IL-6 receptor has been evidenced in a subgroup of non-Hodgkin's lymphomas, suggesting that this cytokine plays a role in lymphoma growth and in B clinical symptoms. In this study, the effect of the administration of an anti-IL-6 monoclonal antibody (MoAb) was analyzed in 11 patients seropositive for human immunodeficiency virus-1 and suffering from an immunoblastic or a polymorphic large-cell lymphoma. The antibody (BE-8, 10 to 40 mg/day) was administered for 21 days. Neutralization of in vivo IL-6 effect was assessed by monitoring C-reactive protein levels in the serum. In 5 patients, the lymphoma progressed during treatment. Among them were the 2 patients in whom endogenous IL-6 effect was not neutralized. Five patients experienced a stabilization, and 1 a partial remission. This effect on lymphoma growth lasted for 8 to 28 weeks. The anti-IL-6 MoAb had a clear effect on lymphoma-associated fever and cachexia. The mean body weight increase was 1.4 +/- 0.5 kg between day 1 and day 21, and reached 12 kg in 120 days in 1 patient who received three courses of treatment. Side effects were a consistent but moderate thrombocytopenia, and an occasional and moderate decrease of neutrophil counts. Immunization against the MoAb was observed in only 2 patients. These results indicate that in some cases of lymphomas growth of malignant cells may be partially IL-6-dependent and that neutralizing endogenous effect of IL-6 completely abrogates B clinical symptoms.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Emergence of inflammatory alveolar macrophages during rejection or infection after lung transplantation.

Local activation of macrophages may play an important role in immune complications following lung transplantation. To document such a phenomenon, we have investigated the possible changes of alveolar macrophage surface antigen expression after lung transplantation. Using immunocytofluorometry, we have analyzed the phenotype of alveolar macrophages from 41 bronchoalveolar lavage fluids obtained from 19 lung transplant recipients displaying various complications. The strong expression of HLA-DR observed on almost all alveolar macrophages was similar among groups I (no complication), II (minimal acute rejection), and III (mild to severe acute rejection), but was enhanced in group IV (bronchial infection) (P < 0.03). We observed no significant variation in the monocyte lineage CD14 antigen expression among the 4 groups, and about 83% of alveolar macrophages expressed this marker strongly. Membrane expression of the 27E10 antigen that characterizes infiltrating macrophages in acute inflammatory lesions was significantly higher during mild to severe rejection episodes than in controls (P < 0.02) and during bronchial infections (P < 0.05) but not during minimal rejection. Double staining experiments confirmed that 27E10-positive cells in groups III and IV belonged to the macrophage lineage. In addition, the expression of the 27E10 antigen on cultured alveolar macrophages was found to be increased after stimulation by bacterial lipopolysaccharide or IFN-gamma. These results indicate that a particular alveolar macrophage subpopulation is activated during immune events after lung transplantation. This population, recognized by the 27E10 mAb, might be involved in cytokine production during severe acute rejection and infection episodes.

Adolescent↗
PubMed1994

Role of IL-6 in promoting growth of human EBV-induced B-cell tumors in severe combined immunodeficient mice.

To investigate the role of IL-6 as a growth factor in EBV-induced B lymphoproliferative disorders in immune-suppressed patients, we analyzed two B cell lines derived from two different patients for IL-6 production, expression of the p80 chain of the IL-6 receptor, and the effects on cell growth in vitro and in vivo of neutralizing mAbs specific for IL-6. One of the cell lines (LCL41) was shown to produce large amounts of IL-6 and to express IL-6 receptors. Its in vitro growth was weakly inhibited by the anti-IL-6 MAb. After inoculation into SCID mice, this cell line provoked human B cell tumors, the growth of which was controlled by the anti-IL-6 mAb. Indeed, four i.v. infusions of 0.1 mg at days 30 to 42 after i.p. inoculation of cells led to complete remission in most mice and long term survival in 40% of cases. In contrast, the other B cell line (LCL48) produced smaller amounts of IL-6; its growth was not inhibited in vitro by the anti-IL-6 Ab and was poorly blocked in vivo in SCID mice (40% of remissions and 20% of long-term survival). In addition, a clone derived in vivo in SCID mice from LCL48 was completely IL-6-independent. These results demonstrate that B cell tumors transformed in vivo by EBV in immune-suppressed patients are heterogeneous with respect to IL-6 requirements for proliferation. An antitumoral effect in some of them can be achieved by neutralizing the IL-6-dependent proliferative loop.

Animals↗
PubMed1994

[Cytokines and autoimmunity].

By enabling interactions to take place between the various cell populations which form the immune system, cytokines stand at a cross-road in the development of autoimmune phenomena. They also intervene in the activation of autoreactive cells and in the occurrence of the associated inflammatory processes. In some pathological situations they might be directly responsible for the loss of tolerance of the self by the immune system. A similar phenomenon is observed in immunotherapy with recumbent cytokines during which autoimmune manifestations are relatively frequent. Owing to our better knowledge of the role played by cytokines in the genesis and development of the autoimmune process, we can now understand better the mechanism of action of immunosuppressive drugs in autoimmune diseases. This knowledge also emphasizes the value of new pharmacological substances with a more finely targeted immunomodulator activity which are currently being evaluated in this type of diseases.

Autoimmunity↗
PubMed1994

In vivo production of interleukin-10 by non-T cells in rheumatoid arthritis, Sjögren's syndrome, and systemic lupus erythematosus. A potential mechanism of B lymphocyte hyperactivity and autoimmunity.

OBJECTIVE: Interleukin-10 (IL-10) is a potent stimulator of B lymphocytes in vitro. In vivo dysregulation of IL-10 gene expression was therefore analyzed in patients with rheumatoid arthritis (RA), primary Sjögren's syndrome (SS), and systemic lupus erythematosus (SLE). METHODS: Spontaneous production of IL-10 by peripheral blood mononuclear cells was measured using reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay in untreated patients with either RA (n = 10), SS (n = 10), or SLE (n = 10), and in 15 normal control subjects. RESULTS: IL-10 production was dramatically higher in RA, SS, and SLE patients than in controls. In each group, both B lymphocytes and monocytes, but not T lymphocytes, produced IL-10. CONCLUSION: IL-10 production is increased in RA, SS, and SLE. It may play a role in B lymphocyte hyperactivity and in the development of autoimmunity.

Arthritis, Rheumatoid↗
PubMed1994

Increased expression of perforin and granzyme B genes in patients with metastatic melanoma treated with recombinant interleukin-2.

The frequency of peripheral blood cells expressing the perforin gene or the granzyme B gene was evaluated by in situ hybridization in nine patients suffering from metastatic melanoma and treated with recombinant interleukin-2 (rIL-2). A spontaneous expression of both genes was detected in five to seven patients. rIL-2 administration increased the frequency of positive cells in all patients (P < 0.03 for each gene), the highest frequency being reached in the patients who already expressed these genes prior to rIL-2 treatment (P < 0.02). Expressions of the granzyme B gene and of the perforin gene were strongly correlated before IL-2 treatment and they were similarly affected by rIL-2 administration. In contrast, their modification under treatment did not correlate with that of CD56+ cell counts, of natural killer activity and of sCD8 release. This indicates that perforin and granzyme B gene expressions are markers of cytotoxic cell activation independent of those previously described, and that they should be further evaluated in patients with malignancies to delineate their potential value in predicting clinical outcome.

CD8 Antigens↗
PubMed1994

Production of interleukin 6 by granulomas of giant cell arteritis.

IL-6 serum levels are increased in patients suffering from GCA, and this cytokine may play a role in the systemic symptoms associated with this disease. We analyzed by in situ hybridization and immunohistochemistry whether IL-6 production originates from arterial granulomas in GCA. Seven arterial biopsy specimens taken from patients with histologically proved GCA were studied. IL-6 production was detected in all cases at both the mRNA and the protein levels. IL-6-producing cells were distributed in the intima, in the media, and in the adventitia. Positive cells were clearly enriched in the media, however, and particularly in contact with the internal elastic lamina. The morphology of the IL-6-producing cells showed that they belonged to several cell populations. In the media, most IL-6-producing cells were macrophages, whereas fibroblasts also produced IL-6 in the intima. Neither endothelial cells nor giant cells were found to express the IL-6 gene. Increased IL-6 serum concentrations returned to normal levels in most patients after administration of corticosteroids, indicating that inhibition of IL-6 production by GCA granuloma cells may be one of the mechanisms of action of corticosteroids in this condition. Production of IL-6 in abnormal arteries may thus participate to the systemic manifestations of GCA.

Aged↗
PubMed1994

Transforming growth factor beta in normal human lung: preferential location in bronchial epithelial cells.

BACKGROUND: Transforming growth factor beta (TGF-beta) is an immunomodulatory cytokine regulating the proliferation and differentiation of various cell types. It also contributes to the maintenance of tissue architecture by influencing the production of extracellular matrix components. TGF-beta has been detected in bronchoalveolar lavage fluid from normal human lung, but the nature and distribution of cells containing TGF-beta in this organ remain unknown. METHODS: Fourteen normal human lung specimens were studied by immunohistochemistry with a monoclonal antibody recognizing TGF-beta 1, TGF-beta 2 and TGF-beta 3. RESULTS: TGF-beta was detected in all cases. Bronchial epithelial cells contained the largest amounts of TGF-beta. In these cells the staining was brightest at the apical pole. Macrophages and smooth muscle cells also contained TGF-beta, although less than epithelial cells. No TGF-beta was detected in other cell populations, including endothelial cells, fibroblasts, and pneumocytes. CONCLUSIONS: The bronchial epithelial compartment appears to be the main location of TGF-beta in the normal human lung, suggesting that this cytokine has a pivotal role in the immunological properties of the bronchial mucosa.

Adult↗
PubMed1994

Soluble TNF receptors (TNF-sR55 and TNF-sR75) in lung allograft recipients displaying cytomegalovirus pneumonitis.

Two distinct types of tumor necrosis factor receptors (TNF-R) have been identified (TNF-R55 and TNF-R75). Both TNF-R also exist in soluble forms (TNF-sR), resulting from the release of the extracellular domains (TNF-sR55 and TNF-sR75). TNF-sR may play an important role in vivo as they can bind to TNF alpha and prevent ligand binding to the cellular TNF-R, thus acting as naturally occurring inhibitors of TNF alpha. Sera from lung allograft recipients with cytomegalovirus (CMV) pneumonitis (12 patients) were assayed for TNF-sR55 and TNF-sR75. The concentrations were compared with those from either control lung recipients displaying neither rejection nor infection (12 patients), or lung recipients with allograft rejection (12 patients). Serum TNF-sR55 and TNF-sR75 concentrations were measured by enzyme-linked immunologic binding assay. Serum TNF-sR55 and TNF-sR75 concentrations were significantly higher during CMV pneumonitis (mean +/- SEM: 13.7 +/- 4.7 ng/ml, and 11.7 +/- 2.7 ng/ml, respectively) than during allograft rejection (3.7 +/- 0.3 ng/ml, p < 0.001, and 2.6 +/- 0.6 ng/ml, p < 0.001, respectively). They were also higher than in control subjects (3.6 +/- 0.3 ng/ml, p < 0.001, and 1.9 +/- 0.5 ng/ml, p < 0.001, respectively). Serum TNF alpha concentration was low in case of rejection or in control subjects (< 20 pg/ml). Conversely increased levels of TNF alpha were detected in the serum of six out of the 12 patients with CMV pneumonitis (p < 0.03 versus rejection and control subjects). Ganciclovir treatment of CMV pneumonitis led to a dramatic decrease of TNF alpha, TNF-sR55, and TNF-sR75 serum levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗