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2.
Rev Med Brux ; 23 Suppl 2: 87-91, 2002.
Article in French | MEDLINE | ID: mdl-12584920

ABSTRACT

New immunotherapies derived from biotechnology offer fascinating perspectives in different fields of medicine including anti-infectious vaccines, cancer, organ transplantation and autoimmune diseases. In this paper, we illustrate how the Department of Immunology can contribute to the development of these new treatments within a academic hospital such as the Erasme Hospital at the Université Libre de Bruxelles.


Subject(s)
Allergy and Immunology , Blood Transfusion , Hematology , Hospital Departments , Belgium , Biomedical Research , Hospitals, University , Humans
4.
Mod Pathol ; 13(12): 1293-9, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11144925

ABSTRACT

Hyperplastic lymphoid tissues of the Waldeyer's ring in human immunodeficiency virus (HIV)-infected patients may occasionally contain multinucleated giant cells (MGCs). These cells, which are unrelated to any opportunistic infection, previously have been demonstrated to harbor significant amounts of HIV. Studies undertaken to characterize these MGCs have generated conflicting results: some reports suggested a macrophage origin, whereas others supported a dendritic cell lineage. This study was performed to determine the occurrence of MGCs in a series of adenoid/tonsil specimens from HIV-seropositive patients showing no histological evidence of opportunistic infection in order to further characterize the phenotype of these cells and to investigate the role of a viral infection in their pathogenesis. Adenoid/tonsil tissue specimens from 21 HIV-seropositive patients with no documented opportunistic infection were scrutinized for the presence of MGCs and evaluated immunohistochemically on paraffin sections by antibodies directed against various macrophage and DC antigens. These antigens included CD68, the macrophage marker 3A5, major histocompatibility complex Class II, S-100 protein, CD1a, and CD83. Additional immunostainings directed at CD21 and CD35 as well as at the HIV-associated p24 antigen were also performed. Finally, the presence of Epstein-Barr virus and human herpesvirus 8 viral sequences was investigated by in situ hybridization and by polymerase chain reaction analysis, respectively. MGCs were found in 14 patients (66.7%), regardless of gender, age, method of viral transmission, CD4 cell count, viral load, or ethnic group. These cells were mostly localized at the lymphoepithelium layer of the tonsillar crypts and, to a lesser extent, in the interfollicular areas of the underlying lymphoid tissue, which consistently exhibited features of follicular hyperplasia. Phenotypically, MGCs were found to be CD68+, 3A5+, major histocompatibility complex Class II+, S-100 protein+/-, CD1a-, CD21-, CD35-, and CD83-. Although the HIV-associated p24 protein was consistently present in the cytoplasm of these cells, no sign of Epstein-Barr virus or human herpesvirus 8 infection could be demonstrated. Consequently, our study didn't show any conclusive evidence to support that MGCs in hyperplastic lymphoid tissues of the Waldeyer's ring from HIV-seropositive patients originated from dendritic cells. The definite nature of these cells has yet to be elucidated, but it is plausible that they simply represent activated macrophages that are infected with HIV present in the oropharyngeal secretions during the circulation of their precursor through the lymphoepithelium area of adenoids and tonsils.


Subject(s)
Adenoids/pathology , Giant Cells/pathology , HIV Infections/pathology , Palatine Tonsil/pathology , Adenoids/metabolism , Adult , Cell Nucleus/ultrastructure , Child , Child, Preschool , Female , Giant Cells/metabolism , HIV Infections/metabolism , Humans , Immunohistochemistry , Male , Middle Aged , Palatine Tonsil/metabolism
6.
J Cutan Pathol ; 25(7): 394-400, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9765026

ABSTRACT

We report the case of a 20 year-old caucasian woman who presented a primary subcutaneous panniculitis-like T-cell lymphoma (SPTCL) as an invasive tumor of the chest wall. Herein, the neoplastic cells were found to express a CD3+CD8+ phenotype but also displayed variably the natural killer (NK)-associated antigens CD56 and CD57 as well as granzyme B. On cytological examination, these cells showed a large granular lymphocyte (LGL)-like morphology with presence of azurophilic granules in their cytoplasm. Electron dense and membrane bound granules like those found in cytotoxic T lymphocytes (CTL) were also demonstrated by electron microscopy. Neither rearrangement of the T-cell receptor subunits nor Epstein-Barr virus (EBV) genome was observed at the molecular level. The LGL-like features of the neoplastic cells found in this case and the presence of NK-associated antigens provide additional support to the cytotoxic derivation of most SPTCL.


Subject(s)
Lymphoma, T-Cell/pathology , Panniculitis/pathology , Soft Tissue Neoplasms/pathology , Adult , Biomarkers, Tumor/metabolism , Female , Humans , Immunohistochemistry , Immunophenotyping , Killer Cells, Natural/metabolism , Killer Cells, Natural/pathology , Killer Cells, Natural/ultrastructure , Lymphoma, T-Cell/metabolism , Lymphoma, T-Cell/ultrastructure , Microscopy, Electron , Panniculitis/metabolism , Soft Tissue Neoplasms/metabolism , Soft Tissue Neoplasms/ultrastructure , T-Lymphocytes/metabolism , T-Lymphocytes/pathology , T-Lymphocytes/ultrastructure , Thoracic Neoplasms/metabolism , Thoracic Neoplasms/pathology , Thoracic Neoplasms/ultrastructure
7.
Nephrol Dial Transplant ; 13(1): 34-6, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9481712

ABSTRACT

BACKGROUND: Infusion of donor bone marrow cells induces tolerance in allograft models. CD34+ stem cells present in human bone marrow could be endowed with tolerogenic properties. METHODS: CD34+ stem cells were isolated from bone marrow extracted from vertebral bodies of cadaveric donors. Donor CD34+ cells (0.6-3.7 x 10(6)/kg) were infused during surgery in 10 kidney transplant recipients receiving OKT3 as induction therapy. Chimerism was investigated using nested PCR for donor-specific HLA alleles. RESULTS: The infusion of CD34+ stem cells was perfectly tolerated. Five patients remained free of acute rejection at follow-up, 47-325 days post-operatively. The five other patients underwent a single episode of corticosensitive acute rejection. Long-term chimerism was not induced in the seven patients investigated for the persistence of donor DNA. CONCLUSIONS: Infusion of donor CD34+ stem cells in kidney transplantation is safe. The clinical usefulness of the procedure remains to be established.


Subject(s)
Antigens, CD34/analysis , Hematopoietic Stem Cell Transplantation , Kidney Transplantation , Adult , Cadaver , Humans , Middle Aged
9.
Ann Hematol ; 74(3): 149-53, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9111430

ABSTRACT

A particular case of marginal zone B-cell lymphoma (MZBCL) presenting with leukemic lymphocytes is reported. In the present observation, the leukemic cells not only displayed a remarkable morphological fluctuation but also had an unusual phenotype, changing with time. These phenotypic features, which have been functionaly investigated by in vitro assays, might simply reflect an activation state depending on the microenvironment. Because of its disconcerting similarities with hairy cell leukemia (HCL) and splenic lymphoma with villous lymphocytes (SLVL), this case relaunches the debate about whether close relationships might exist between the splenic marginal zone, SLVL and HCL.


Subject(s)
Leukemia/genetics , Leukemia/pathology , Lymphoma, B-Cell/genetics , Lymphoma, B-Cell/pathology , Antigens, CD19/analysis , B-Lymphocytes/immunology , Genetic Heterogeneity , Humans , Leukemia, Hairy Cell/pathology , Lymphocytes/pathology , Male , Middle Aged , Phenotype
10.
Leuk Lymphoma ; 24(5-6): 545-51, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9086445

ABSTRACT

Little is known about the function of the T lymphocytes in lymphocyte predominance Hodgkin's disease. We report here the case of a 37-year-old man with a diffuse LPHD, featuring a similar increase in T lymphocytes in both the peripheral blood and the tumor, thus allowing for their characterization by functional assays. These cells were CD4+CD45RO+ and produced high amounts of IL-2 and IFN-gamma, consistent with a TH1-type profile. This subset of T helper cells is involved in cellular immunity and could reflect a cytotoxic reaction directed against the neoplastic cells.


Subject(s)
Hodgkin Disease/pathology , T-Lymphocytes/physiology , Adult , Antigens, CD/analysis , Flow Cytometry , Hodgkin Disease/blood , Hodgkin Disease/immunology , Humans , Immunity, Cellular/physiology , Interferon-gamma/biosynthesis , Interleukin-2/biosynthesis , Lymphocyte Activation , Male , T-Lymphocytes/immunology , T-Lymphocytes/metabolism
11.
J Lab Clin Med ; 128(6): 612-7, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8960645

ABSTRACT

DDAVP-related hyponatremia induces a blood volume expansion, but the analysis of fluid distribution in the vascular compartment has given controversial results in previous animal and human studies. In 5 healthy males, hyponatremia was induced by DDAVP and a free water intake during 3 days. Serum sodium concentration decreased from 138 +/- 0.8 mEq/L to 123 +/- 2.7 mEq/L on day 3. The plasma volume measured by dilution of marked albumin rose from 3033 +/- 230 ml to 3320 +/- 295 ml (p < 0.01). The mean corpuscular volume measured by microhematocrit increased slightly from 91.5 +/- 3.8 pl to 92.6 +/- 3.7 pl (p < 0.02). The red blood cell volume calculated with hematocrit and plasma volume did not change significantly (2565 ml to 2567 ml; not significant). In the present work, we demonstrated that in males the expansion of the plasma compartment almost completely amounted for the water retention in the intravascular volume. The erythrocyte volume increased only slightly, a finding that is consistent with an almost perfect adaptation of the erythrocyte cells to the hypoosmolality.


Subject(s)
Deamino Arginine Vasopressin/pharmacology , Erythrocytes/drug effects , Hyponatremia/chemically induced , Renal Agents/pharmacology , Water/metabolism , Administration, Intranasal , Adult , Blood Volume/drug effects , Deamino Arginine Vasopressin/administration & dosage , Erythrocyte Indices , Erythrocytes/physiology , Hematocrit , Hemodynamics , Humans , Hyponatremia/etiology , Male , Renal Agents/administration & dosage , Reproducibility of Results , Sodium/blood
13.
Am J Pathol ; 147(1): 176-82, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7604878

ABSTRACT

Interleukin (IL)-10 is a novel cytokine produced by a variety of cells, including monocytes/macrophages, upon exposure to lipopolysaccharide (LPS). Recent observations indicate that, in turn, IL-10 exerts suppressive effects on macrophage response to LPS. Because mesangial cells are also a target for LPS, we have examined the potential role of IL-10 in the regulation of mesangial cell response to LPS. To this aim, we have studied the synthesis and the autocrine/paracrine function of IL-10 in cultured mouse mesangial cells. IL-10 mRNA expression and IL-10 protein secretion were determined by a reverse transcription polymerase chain reaction technique and a specific enzyme-linked immunosorbent assay, respectively. No IL-10 mRNA expression was detectable in unactivated cells. LPS induced IL-10 mRNA expression in a dose-dependent fashion (1 to 100 micrograms/ml). In addition, LPS induced IL-10 protein release that was both dose dependent (1 to 100 micrograms/ml) and time dependent (24 to 72 hours). We have also studied the effect of IL-10 on the production of inflammatory mediators by LPS-activated mouse mesangial cells. Whereas recombinant IL-10 inhibited the generation of tumor necrosis factor-alpha (TNF-alpha) and IL-1 beta by 90 and 60%, respectively, it did not affect the formation of nitric oxide-derived nitrite (NO2-) and nitrate (NO3-). As shown by the use of anti-IL-10 monoclonal antibody, endogenously produced IL-10 affected the generation of TNF-alpha but neither that of IL-1 beta nor that of NO2- and NO3-. Finally, we have examined whether conditions known to also reduce the generation of TNF-alpha modified the expression of IL-10. Of all the conditions tested, only the addition of desferrioxamine and transforming growth factor-beta were found to increase IL-10 release. Together, these data demonstrate that mesangial cell-derived IL-10 has important regulatory effects on the inflammatory response of these cells to LPS because of its capacity to blunt TNF-alpha generation.


Subject(s)
Escherichia coli , Glomerular Mesangium/metabolism , Interleukin-10/physiology , Lipopolysaccharides/pharmacology , Animals , Base Sequence , Cells, Cultured , Cytokines/biosynthesis , Cytokines/drug effects , DNA Primers/chemistry , Dose-Response Relationship, Drug , Glomerular Mesangium/cytology , Glomerular Mesangium/drug effects , Interleukin-10/biosynthesis , Interleukin-10/pharmacology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C3H , Molecular Sequence Data , Nitric Oxide/biosynthesis , Polymerase Chain Reaction , RNA, Messenger/biosynthesis , Recombinant Proteins , Transforming Growth Factor beta/pharmacology
14.
J Electrocardiol ; 27 Suppl: 113-7, 1994.
Article in English | MEDLINE | ID: mdl-7884344

ABSTRACT

This study reports preliminary results on 45 patients who underwent percutaneous transluminal coronary angioplasty (PTCA); 120-lead data (including the 12-lead standard electrocardiogram [ECG]) were recorded before, during, and after balloon inflation. Twenty-one patients underwent PTCA for left anterior descending coronary disease, 13 for right coronary artery disease, and 10 for left circumflex; 1 patient had combined left anterior descending and right coronary artery disease. In each patient, voltage data recorded during the various phases of the procedure were compared with the patient's own baseline data. In 18 patients, 120 leads were also recorded 24 hours after PTCA. In this study, the usefulness of the standard 12-lead ECG was investigated in locating the coronary artery being occluded, in elucidating the mechanisms of the QRS changes, and in identifying changes occurring 24 hours after completion of the procedure. Results indicate that the observation of ST elevation in the 12-lead ECG may lead to ambiguous interpretation. Also, limiting observation to ST-T patterns alone instead of including QRS changes further hampers correct identification of the involved vessel. QRS modifications during inflation are interpreted as conduction disturbances, although other mechanisms are evoked: study of surface maps may contribute to the understanding of these mechanisms. Changes present 24 hours later are visible in the standard leads, but again, in the absence of the thoracic potential distribution, these are difficult to interpret. These changes were different from those observed after cessation of inflation at the end of the procedure. It is hypothesized that next-day changes may reflect reperfusion injury and/or represent myocardial stunning. Presence of injury and reversibility of changes require further investigation. Also, biochemical markers such as creatine kinase-MB mass, creatine kinase-MB activity, myoglobin, and troponin-T may help elucidate the significance of these findings.


Subject(s)
Angioplasty, Balloon, Coronary , Electrocardiography , Coronary Disease/physiopathology , Coronary Disease/therapy , Humans
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