PubMed HealthSearch

Biomedical subjects

D Glotz

Publications and source records attributed to D Glotz.

At least 19 recordsLinked to original sources

Human immunoglobulins inhibit thrombin-induced Ca2+ movements and nitric oxide production in endothelial cells.

Binding of natural antibodies to endothelial cell plays an important role in hyperacute xenograft rejection between discordant species. Human intravenous immunoglobulins (IVIg) delay this hyperacute rejection, but their mechanisms of action on endothelial cells have to be defined. Here we demonstrate that IVIg dose-dependently prevent thrombin from eliciting cytosolic Ca2+ movements and nitric oxide (NO) production in aortic endothelial cells from guinea pig. The Ca2+ response to thrombin was similarly affected by IVIg whether they were removed or not from the incubation medium before stimulation. Pretreatment by rat natural antibodies also suppress the thrombin-induced Ca2+ peak corresponding to Ca2+ release from intracellular stores but stimulate the subsequent sustained increase in [Ca2+]i and the release of NO. The action of human intravenous immunoglobulins seems to be selective for the thrombin receptor because they do not affect [Ca2+]i and NO responses to endothelin-1 or thapsigargin. However, these antibodies also suppress the first phase of the cytosolic Ca2+ response to ATP, which does not release NO under our experimental conditions. These observations raise the possibility that IVIg selectively interact with targets localized on plasma membrane of endothelial cells for controlling receptor-activated Ca2+ pathways and NO release.

Animals

Antibodies to a conserved region of HLA class I molecules, capable of modulating CD8 T cell-mediated function, are present in pooled normal immunoglobulin for therapeutic use.

Intravenous immunoglobulin (IVIg) is increasingly used for the treatment of autoimmune diseases and the prevention of infections and of graft versus host reactions in recipients of allogeneic bone marrow transplants. The immunomodulatory effects of IVIg are largely dependent on their ability to interact with membrane molecules of lymphocytes. We report here that IVIg recognizes the B07.75-84 peptide, corresponding to a conserved region of the alpha I helix of the first domain of HLA-B7 01, which represents a nonpolymorphic determinant of HLA class I molecules. Intact IVIg and its F(ab')2 fragments bound to the peptide as well as to purified soluble HLA and to HLA on a human T cell line. Binding of IVIg to HLA was assessed by ELISA, immunofluorescence, and real-time analysis of the interaction using the BIAlite system. The binding of antipeptide antibodies to HLA was inhibited by free peptide. Antipeptide antibodies isolated from IVIg by affinity chromatography inhibited CD8 cell-mediated cytotoxicity of an influenza virus-specific human T cell line. The presence in IVIg of antibodies to critical regions of HLA class 1 molecules suggests a possible role for IVIg in modulation of class-I-restricted cellular interactions in the immune response.

Amino Acid Sequence

Hemophagocytic histiocytosis (HH) in renal transplant recipients under ciclosporin therapy: report of the first two cases.

Hematophagocytic histiocytosis is a clinicopathologic syndrome associating fever, liver dysfunction, blood cytopenia and coagulation abnormalities with hematophagocytosis in bone marrow and lymphoïd organs. This syndrome is found in immunocompromized patients and is triggered by infection. We describe herein the first 2 cases of HH in renal transplant recipients treated with ciclosporin. In our 1st case, H.H. was not recognized early and the patient died. In the 2nd case, prompt diagnosis associated to an anti-infectious treatment led to recovery. The clinician must thus be aware of the possibility of such a syndrome in renal transplant patients. Identification and treatment of the underlying infection is mandatory to avoid a fatal outcome.

Adult

[Renal involvements in human immunodeficiency virus infection].

Two main types of renal disorder may affect the HIV-infected patients. The first type characterized by acute renal failure is not related directly to HIV infection, but results from complications secondary to diagnosis and therapeutic intervention in patients with severe immunodepression. The second type of renal complication includes three quite specific histological renal patterns. The typical "HIV-associated nephropathy" (HIVN), involves essentially the black population, both in Europe (84%) and in North America (83%) and could represent a pathogen-induced disease occurring on a specific genetic background. The two other types of nephropathy, i.e. immune complex-type glomerulonephritis and tubulointerstitial nephritis, involve both black and white seropositive populations and might be the consequence of dysregulation of the immune system.

AIDS-Associated Nephropathy

[Aspergillosis and renal, heart and lung transplantation].

The increase of organ transplantations during the last decades conjointly with the prescription of heavy immunosuppressive drugs, has led to an increased incidence of new invasive aspergillosis (IA). This study is a report of the Broussais Hospital experience from 1968 to 1993 on kidney, heart and heart and lungs transplantations. It concerns 21 IA cases. Incidence was 0.5% for kidney, 4.5% for heart and 18% for heart and lungs transplantations. The most important risk factors were the increase of immunosuppressive therapy (66% of the cases), neutropenia (19%), and renovation of the hospital wards (36%). Lung was the most frequent site of infection (95% of the cases), clinical symptoms were no significant. Diagnosis procedures were realised on biopsy (23%) and on bronchoalveolar lavage (66%). Usual amphotericin B treatment was disappointing: mortality rate of 77%, the liposomal preparation of the drug seemed to be more efficient: mortality rate of 50%. Itraconazole appeared to be used in succession with a careful adaptation of posology. Prophylactic amphotericin B in a local way (sprays and aerosols) led to a good efficiency jointly with the patient isolation during constructions in the hospital area.

Adolescent

Preeclampsia associated focal and segmental glomerulosclerosis and glomerular hypertrophy: a morphometric analysis.

Renal biopsies from hypertensive pregnant women performed 8 to 10 days postpartum were processed by morphometric analysis. We allocated the 74 patients into four groups according to the respective forms of pregnancy hypertension, i.e. preeclampsia and gestational hypertension. Groups I and II included preeclamptic women, with (group I) or without (group II) de novo FSGS. Groups III and IV included biopsies of women with isolated gestational hypertension, appeared during the third trimester (group III) or earlier (group IV). The control group included 17 biopsies from age-matched nonpregnant women presenting with isolated hematuria. Glomerular lesions of typical preeclampsia were seen in all the biopsies of groups I and II, and in some of women with gestational hypertension of groups III and IV. Our morphometric analysis of these renal biopsies showed a progressive increase in glomerular size from early gestational hypertension, gestational hypertension of the 3rd trimester, isolated preeclampsia, and finally preeclamptic nephropathy associated with FSGS. The largest glomeruli were seen in preeclamptic women with severe hypertension and histologic lesions of preeclampsia with FSGS. Thus, both systemic hypertension and glomerular hypertrophy seem necessary to induce FSGS in this type of pathology.

Adult

[The transplanted kidney. Role of imaging in early non-functioning grafts].

Renal failure following transplantation can be classified in two groups: initial non function characterized by the absence of renal function after transplantation and delayed secondary non function after an initial improvement. In the first group, the most frequent etiology is an acute tubular necrosis (30 to 50% of the cases) which usually heals within three weeks. Arterial thrombosis are rare but of very bad prognosis. In the second group, the most frequent cases are acute rejection, urological complications, renal artery stenosis, urinary infections and cyclosporine, intoxication. Diagnostic imaging, and especially the color Doppler flow, is very effective in obtaining diagnosis. Vascular or urological complications are to be confirmed by contrasted opacifications. In the absence of vascular or urological obstruction renal failure must be related to a renal parenchymal disease. This may be acute tubular necrosis, a rejection, a pyelonephritis or a medicinal intoxication depending on clinical symptoms, the time of their apparition and the results of biological examinations.

Acute Kidney Injury