PubMed Health⌕ Search

Biomedical subjects

M Jourdan

Publications and source records attributed to M Jourdan.

At least 55 records · Page 3Linked to original sources

IFN-alpha induces autocrine production of IL-6 in myeloma cell lines.

IL-6 is a major tumor growth factor in human multiple myeloma. Myeloma cell lines, which have the same phenotypic characteristics and Ig gene rearrangements as the original fresh myeloma cells and whose growth is strictly dependent on exogenous IL-6 similar to fresh myeloma cells, have been reproducibly established. We show here that IFN-alpha stimulated the growth of five of six of these human myeloma cell lines by inducing an autocrine production of IL-6 in myeloma cells. Indeed, IFN-alpha induced IL-6 mRNA accumulation and IL-6 production in myeloma cells and the IFN-alpha-induced growth of these cells was inhibited by anti-IL-6 mAb. Moreover, IFN-alpha made possible the rapid emergence of autonomously growing myeloma cell sublines, which produced IL-6 as an autocrine growth factor. As IFN-alpha has a potential therapeutical interest for multiple myeloma, the present study opens up new directions for studying its effects on the myeloma clone in vivo.

Cell Division↗

Murine anti-interleukin-6 monoclonal antibody therapy for a patient with plasma cell leukemia.

A patient with primary plasma cell leukemia resistant to chemotherapy was treated for 2 months with daily intravenous injections of anti-interleukin-6 (IL-6) monoclonal antibodies (MoAbs). The patient's clinical status improved throughout the treatment and no major side effects were observed. Serial monitoring showed blockage of the myeloma cell proliferation in the bone marrow (from 4.5% to 0% myeloma cells in the S-phase in vivo) as well as reduction in the serum calcium, serum monoclonal IgG, and the serum C-reactive protein levels. The serum calcium and serum monoclonal IgG corrected by approximately 30%, whereas the C-reactive protein corrected to undetectable levels during treatment. No major side effects developed, although both platelet and circulating neutrophil counts decreased during anti-IL-6 therapy. A transient immunization was detected 15 days after the initiation of the treatment, which could explain the recovery of myeloma cell proliferation after 2 months of treatment (2% myeloma cells in the S phase). In conclusion, this first anti-IL-6 clinical trial demonstrated the feasibility of injecting anti-IL-6 MoAbs, and also a transient tumor cytostasis and a reduction in IL-6-related toxicities. It gave insight into the major biologic activities of IL-6 in vivo and may serve as a basis for further development of anti-IL-6 therapy in myeloma and other IL-6-related diseases.

Acute-Phase Proteins↗

The expression of Fc receptors for immunoglobulin G in human rectal epithelium.

The rectal mucosa is one of the routes of transmission of the HIV virus, although the mechanism of transmission is unknown. We carried out an immunohistological investigation of human rectal epithelium to detect CD4 glycoprotein and Fc receptors (FcR) for immunoglobulin G which may be involved in HIV infection. CD4 was not detected by monoclonal antibodies (MAb) in normal rectal epithelial cells, although CD4+ mononuclear cells were found in the lamina propria of the rectum. FcR3 and FcR2 were, however, detected in surface or crypt epithelial cells of rectal mucosa, using MAb to CD16 and CD32, respectively. In addition, CD16 messenger RNA (mRNA) was found in surface and crypt epithelial cells by in situ hybridization using an RNA probe. FcR3 and FcR2 were also detected in fetal recto-colonic tissue by immunohistology, suggesting that these are constitutive receptors. FcR3 and FcR2 gene transcripts were then demonstrated in fetal recto-colonic tissue using the polymerase chain reaction to amplify a portion of FcR3 and FcR2 coding sequences in complementary DNA (cDNA) prepared from fetal RNA. These findings suggest the possibility that rectal transmission of HIV-antibody complexes might be facilitated by the expression of FcR3 and FcR2 in rectal epithelial cells.

Acquired Immunodeficiency Syndrome↗

Granulocyte-macrophage colony-stimulating factor synergizes with interleukin-6 in supporting the proliferation of human myeloma cells.

The role of granulocyte-macrophage colony-stimulating factor (GM-CSF) in the growth of multiple myeloma (MM) was investigated in 21 patients with MM. In 17 patients with proliferating myeloma cells in vivo, recombinant GM-CSF significantly increased the endogenous-IL-6-mediated spontaneous myeloma cell proliferation occurring in 5-day cultures of tumor cells in vitro (P less than .01). Furthermore, GM-CSF was detected in 5-day culture supernatants of myeloma bone marrow cells. This endogenous GM-CSF was produced by the myeloma bone marrow microenvironment but not by myeloma cells and contributed to the spontaneous myeloma-cell proliferation observed in 5-day cultures. In fact, this proliferation was partially blocked (67%) by anti-GM-CSF monoclonal antibodies. The stimulatory effect of rGM-CSF was mediated through IL-6 because it was abrogated by anti-IL-6 monoclonal antibodies. rGM-CSF did not reproducibly increase the endogenous IL-6 production in short-term cultures of bone marrow cells of MM patients. Using an IL-6-dependent myeloma cell line (XG-1 cell line), rGM-CSF was shown to act directly on myeloma cells stimulating by twofold their IL-6 responsiveness. rGM-CSF did not induce any IL-6 production in XG-1 cells, nor was it able to sustain their growth alone. Although no detectable GM-CSF levels were found in the peripheral or bone marrow blood of MM patients, it is possible that GM-CSF, produced locally by the tumoral environment, enhances the IL-6 responsiveness of myeloma cells in vivo in a way similar to that reported here in vitro.

Aged↗

Constitutive production of interleukin-6 and immunologic features in cardiac myxomas.

The constitutive production of interleukin-6 (IL-6), a potent hepatocyte-stimulating factor and B cell-differentiating factor, was demonstrated in 3 patients with cardiac myxomas. Tumor cells from the only patient who presented with immunologic features produced 14-23-fold higher levels of IL-6 than those from the 2 patients who lacked such features. A significant serum IL-6 level (56 pg/ml), greater than that observed in patients with active rheumatoid arthritis, was also observed only in this patient, with a subsequent return to an undetectable level after surgical removal of the tumor. This was associated with a regression of the immunologic features. This same patient was observed to have an IL-6-dependent, proliferative polyclonal plasmacytosis of the bone marrow. These observations demonstrate that an overproduction of IL-6 by cardiac myxoma cells, in association with a systemic passage of this IL-6, may be responsible for the immunologic features similar to those observed in true autoimmune diseases such as rheumatoid arthritis.

Acute-Phase Proteins↗

Cloning of the genome of a densovirus and rescue of infectious virions from recombinant plasmid in the insect host Spodoptera littoralis.

We have cloned an infectious genome of the Junonia coenia densonucleosis virus (JcDNV) into the bacterial plasmid pBR322. The viral genome could be rescued from the recombinant plasmid pBRJ by transfection of pBRJ DNA to sensitive Spodoptera littoralis larvae. pBRJ DNA produced a typical viral infection and a comparable percentage of larvae became infected following inoculation of equivalent amounts of purified virion DNA or cloned viral DNA. Virions extracted from transfected larvae were indistinguishable from wild-type (wt) virions with regard to their biophysical and biological properties. In particular, rescued virions were as infectious as wt virions and showed identical restriction profiles of their genome. In contrast, subcloning of JcDNV DNA deleted at both extremities of a sequence of ca 250 or ca 100 bp resulted in the inability of the recombinant plasmids to initiate a viral infection. These data suggest that, as for vertebrate parvoviruses, the inverted terminal repeats display essential functions in the rescue process and replicative cycle of densoviruses. This is the first report of the molecular cloning of the infectious genome from an insect parvovirus, and more generally from an invertebrate virus. pBRJ should provide an efficient tool to further define the organization of the JcDNV genome and compare it to other parvoviruses.

Animals↗

Restriction maps and sequence homologies of two densovirus genomes.

The genomes of Junonia coenia densonucleosis virus (JcDNV) and Galleria mellonella densonucleosis virus (GmDNV) were analysed by restriction endonuclease analysis and Southern blot hybridization. A total of 37 and 33 restriction sites were mapped on JcDNV and GmDNV DNA, respectively. BglI, HaeII and BstEII were site-specific for JcDNV DNA, and BglII and ClaI for GmDNV DNA. The two genomes had nearly identical maps for several restriction endonucleases and Southern blot hybridization using a total genomic JcDNV probe indicated extensive DNA sequence homologies spanning the entire length of the two genomes. Symmetrical cleavage sites, mapping at the extremities of both genomes, confirmed the presence of inverted terminal repeats of at least 420 to 440 bases in length.

Animals↗

Prioritising waiting lists.

The 'top 22' patient conditions on the general surgical waiting list at Guy's Hospital were rated independently by five general surgeons. Each surgeon estimated the peri-operative mortality rates associated with each treatment; the proportion of patients who failed to benefit; the effect of successful treatment on life expectancy and on the patients' quality of life. the mean values were used to estimate the expected net benefits (in terms of quality-adjusted life-years) from treatment one year earlier than might otherwise have been the case. These benefits were then related to the operating times and length of stay associated with each treatment; this identified which treatments offered the greatest benefit per unit of each constrained resource. Of all conditions examined anal fissures where shown to be the least resource intensive in relation to the benefits generated, whilst varicose veins and epigastric hernias proved otherwise. For the full potential of this approach to be realised it needs to be repeated in other places and in other specialties. It nevertheless offers a more rational basis for interpreting waiting list data than presently exists and by using the short-cut methods is a relatively cheap way of generating much useful data.

Data Collection↗

Spontaneous secretion of tumor necrosis factor-beta by human myeloma cell lines.

Abnormal bone remodelling in the vicinity of tumor cells is a common, early feature of multiple myeloma, characterized by excessive bone resorption which is mediated by local soluble factors called osteoclast activating factors (OAF). Since interleukin-1 (IL-1) and tumor necrosis factors (TNF) are potent, synergistic OAF produced by cells of the B-cell lineage, the authors investigated the spontaneous secretion of these cytokines by 11 human myeloma cell lines (HMCL). No HMCL secreted either IL-1, the most powerful OAF, or contra IL-1. In contrast, all of the lymphoblastoid cell lines assayed produced significant IL-1 activity. Ten of the 11 HMCL secreted a significant TNF activity. This was completely eliminated by an anti-TNF beta monoclonal antibody but not affected by an anti-TNF alpha antiserum. The data from this study suggest that TNF beta is involved in myeloma bone resorption, but not IL-1, which is, however, known as one of the most potent OAF.

Antibodies, Monoclonal↗

The defect in peripheral blood B-cell activation in patients with multiple myeloma is not due to a deficiency in the production of B-cell growth and differentiation factors.

The suppression of B lymphopoiesis is a major feature of multiple myeloma (MM). In this disease, there is a striking defect in the response of peripheral blood B cells to pokeweed mitogen (PWM). Normally, B-cell activation depends on B-cell growth factors (BCGFs) and B-cell differentiation factors (BCDFs), produced by peripheral blood mononuclear cells. We therefore evaluated whether the production of these cytokines was defective in patients with MM. We have studied the production of BCGFs (using the anti-mu assay) and, particularly, interleukin-2 and interferon-gamma, two well-documented BCGFs. No defect in the production of BCGFs, interleukin-2, and interferon-gamma was found in patients with active (N = 14) or stable (N = 10) MM, compared with healthy donors (N = 13). The production of BCDFs (i.e., overall activity) was also evaluated and, more particularly, that of interleukin-6 (IL-6). This cytokine is a potent BCDF which is essential in the PWM-induced activation of B cells, acting at the terminal stages of B-cell differentiation. Again, no defect in the production of BCDFs and IL-6 was found in patients with MM. Therefore, the ability to secrete cytokines controlling the process of B-cell activation is not affected in such patients. This indicates that the profound failure of humoral immune response is not due to deficiency of peripheral blood mononuclear cells producing these factors.

B-Lymphocytes↗

Dukes A carcinoma after colonic interposition for oesophageal stricture.

The management of caustic and peptic oesophageal strictures refractory to medical treatment and repeated dilatations continues to be a challenge. Colonic interposition with subtotal oesophagectomy is felt by many surgeons to be the best treatment. Complications in the short and long term are, however, frequent. We report a case of a colonic carcinoma originating in a colonic interposition and growing up into the oesophageal remnant.

Adenocarcinoma↗

Serum levels of interleukin 6, a potent myeloma cell growth factor, as a reflect of disease severity in plasma cell dyscrasias.

Using a specific and very sensitive (1 pg = 1 U) bioassay, we investigated the presence of IL-6, a potent myeloma cell growth factor, in the sera of 131 subjects with plasma cell dyscrasias. 22 had monoclonal gammopathy of undetermined significance (MGUS), 13 had smoldering myeloma (SMM), 85 had overt multiple myeloma (MM), and 11 had plasma cell leukemia (PCL). Significant serum IL-6 levels were detected in only 3% of the MGUS/SMM group, but in 35% of the overt MM group and 100% of the PCL group. During overt MM, IL-6 was detected in 37% of the patients at diagnosis, 13% of those with stable MM, and 60% of those with fulminating disease. These data demonstrate that serum levels of IL-6, a potent myeloma cell growth factor in vitro, correlate with disease severity in plasma cell dyscrasias. Serial studies performed in 3 patients and correlative studies with labeling index in vivo in 25 patients have confirmed this concept. Taken together, this suggests that this cytokine is probably involved in vivo during the progressive phase of MM. Thus, anti-IL-6 or anti-IL-6 receptor antibodies could be useful as therapeutic agents at this stage of the disease.

Humans↗

Phenotypic analysis of human myeloma cell lines.

Multiple myeloma (MM) is a B-cell malignancy characterized by the accumulation, primarily in bone marrow, of a clone of plasma cells. The nature of the stem cells feeding the tumoral compartment is still unknown. To investigate this special point, we have studied the phenotypes of nine well-known human myeloma cell lines (HMCLs) and compared them with those of normal lymphoblastoid cell lines (LCLs). Twenty-four clusters of differentiation involved in B lymphopoiesis were investigated using a panel of 65 monoclonal antibodies (MoAbs). For each cluster, the percentage of positive cells and the antigen density were determined, giving rise to a "quantitative phenotype". We thus classified the HMCLs into two different groups: those with cytoplasmic mu chains (c mu+) and those without (c mu-). In the first (c mu+) group, comprising seven cell lines, the HMCLs had a phenotype of pre-B/B cells close to that of Burkitt's lymphoma cell lines. They expressed low densities of surface mu chains, without detectable cytoplasmic or surface light chains. Three of them were infected with the Epstein Barr virus (EBV). These c mu+ HMCLs bore most of the B-cell antigens except CD23. They expressed the CALLA antigen (CD10) and lacked the plasma-cell antigen PCA1. In contrast, LCLs expressed surface light chains, high densities of CD23, low densities of PCA1 antigen, and no CD10 antigen. The c mu- HMCLs had a plasma-cell phenotype, lacking most of the B-cell antigens and expressing high densities of PCA1 antigen.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, Differentiation, B-Lymphocyte↗

Paracrine rather than autocrine regulation of myeloma-cell growth and differentiation by interleukin-6.

To explore the mechanisms involved in the pathogenesis of human multiple myeloma (MM), we investigated the potential role of interleukin-6 (IL-6), a B-cell differentiation factor in humans, and a growth factor for rat/mouse heterohybridomas and murine plasmacytomas. Using a heterohybridoma assay, we found that two well-documented human myeloma cell lines, RPMI 8226 and U266, did not secrete IL-6 and did not express RNA messengers for IL-6. Neutralizing antibodies to IL-6 did not inhibit their proliferation, and recombinant IL-6 did not stimulate it. Taken together, these data show that IL-6 is not the autocrine growth factor of these human myeloma cell lines. A high production of IL-6 was found in the bone marrows of patients with fulminating MM, compared with patients with inactive or slightly active MM, or to healthy donors. This IL-6 production was assigned to adherent cells of the bone-marrow environment but not to myeloma cells. A spontaneous proliferation of myeloma cells freshly isolated from patients was observed in short-term cultures. Recombinant IL-6 was able to amplify it two- to threefold. The spontaneous proliferation of the myeloma cells was inhibited by anti-IL-6 antibodies and reinduced by recombinant IL-6. After 2 to 3 weeks of culture, the myeloma-cell proliferation progressively declined and no IL-6-dependent myeloma cell lines could be obtained despite repeated additions of fresh IL-6 and costimulation with other cytokines such as tumor necrosis factor (TNF)beta, or IL-1 beta. These data demonstrated a paracrine but not autocrine regulation of the growth and differentiation of myeloma cells by IL-6.

Aged↗

Production of B-cell growth factor interleukin 2 and gamma interferon by peripheral blood lymphocytes from patients with chronic lymphocytic leukemia of B-cell type.

Chronic lymphocytic leukemia of B-cell type (B-CLL) is a malignant disease characterized by monoclonal proliferation of small lymphocytes of B-cell origin, usually associated with suppression of polyclonal B-cell activation (i.e., proliferation and differentiation). Normal human B-cell proliferation is controlled by different T-cell-derived lymphokines, including interleukin 2 (IL2) and gamma interferon (gamma-IFN), that account for the majority of the B-cell growth factor (BCGF) activity produced by mitogen-activated peripheral blood mononuclear cells (PBMCs). We have previously shown an increased and dysregulated secretion of IL2 in peripheral blood from patients with B-CLL. BCGF, IL2, and gamma-IFN productions by phytohemagglutinin (PHA)-stimulated PBMCs were investigated in 13 patients with active untreated B-CLL and 11 healthy donors. B-CLL PBMCs produced a significant amount of BCGF (6 U/ml) despite the low percentage of T cells (10%) associated with this disease as compared with that found in healthy donors (61%). BCGF production in normal controls and B-CLL patients was tripled after irradiation of PBMCs or addition of indomethacin. gamma-IFN secretion in B-CLL patients was decreased when compared with normal controls. Therefore, when gamma-IFN was calculated per fixed number of T cells, production was significantly higher in B-CLL patients than in normal controls, showing a dilution of the productive cells. This study suggests that T cells from B-CLL patients are functional in terms of BCGF production despite their decreased percentage and abnormalities in surface markers.

Aged↗

Interleukin 2 production in bone marrow of normal individuals and patients associated with B-cell chronic lymphocytic leukaemia.

T-cells from patients with B-cell chronic lymphocytic leukaemia (B-CLL) have abnormal T4/T8 ratios and functions. Previously, we demonstrated that peripheral blood (PB) mononuclear cells from B-CLL patients secrete significant amounts of interleukin 2 (IL2) with an apparent dysregulation of accessory cells controlling this production. In this study, IL2 production was investigated in PB and in bone marrow (BM) from patients with previously untreated B-CLL, mostly in early stages of the disease, and compared to normal donors. A significant secretion was observed in both PB and BM from B-CLL patients after stimulation by phytohaemagglutinin (PHA), with lower amounts in patients with nodular involvement of BM, as compared to interstitial or diffuse involvements. To explore the role of accessory cells in controlling IL2 production, we added phorbol ester or indomethacin to the culture system or irradiated the cells before culture. Phorbol ester significantly increased the IL2 secretion in both the PB and the BM of B-CLL patients. The irradiation or the addition of indomethacin did not enhance the IL2 production in PB from B-CLL patients. However, IL2 secretion increased in the BM cells from B-CLL patients after addition of indomethacin or prior irradiation, in a similar way to that observed in PB and BM of normal controls, suggesting an apparent normal control of the IL2 production in BM from B-CLL patients. In normal controls, we demonstrated that IL2 secretion per T-cell from BM was 5.4-fold greater than that from normal PB, suggesting a very efficient role of accessory cells controlling IL2 production in normal BM.

Aged↗