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C Lebbé

Publications and source records attributed to C Lebbé.

At least 37 records · Page 2Linked to original sources
PubMed1999

No evidence for a role of human herpesvirus type 8 in sarcoidosis: molecular and serological analysis.

The aim of this study was to analyse the association between human herpesvirus type 8 (HHV8) and sarcoidosis. Using nested polymerase chain reaction (PCR), we tested the presence of HHV8 DNA sequences in 13 skin specimens and peripheral blood mononuclear cells from eight patients suffering from sarcoidosis. We also looked for the presence of HHV8 antibodies in the sera of 28 patients with sarcoidosis using three techniques: two indirect immunofluorescence assays and an enzyme-linked immunosorbent assay with recombinant capsid protein fragment encoded by open-reading frame 65. HHV8 PCR analysis was negative while HHV8 serological studies showed an overall prevalence of 18% among patients suffering from sarcoidosis: 43% in patients from sub-Saharan Africa, 17% in patients from Northern Africa, 12.5% in patients from the French West Indies and 0% in French patients. In conclusion, our results do not indicate an association between HHV8 and sarcoidosis but reflect the seroepidemiology of this virus in different geographical regions.

Adult↗
PubMed1998

Clinical and biological impact of antiretroviral therapy with protease inhibitors on HIV-related Kaposi's sarcoma.

OBJECTIVE: To evaluate the clinical and biological impact of protease inhibitors on HIV-associated Kaposi's sarcoma. DESIGN AND SETTING: A cohort of 10 patients included prospectively from April 1996 to June 1997 were studied in one institutional centre after initiation of protease inhibitors. PATIENTS AND METHODS: All patients but one (stable disease) had progressive Kaposi's sarcoma. Three out of 10 patients had stopped specific chemotherapy for Kaposi's sarcoma for more than 4 weeks, three were still under chemotherapy, and four had never received specific treatment of Kaposi's sarcoma. Plasma HIV viral load, human herpesvirus (HHV)-8 viraemia in peripheral blood mononuclear cells (PBMC), and CD4 cell count were sequentially assessed from the beginning of therapy. For six patients, a semiquantitative evaluation of HHV-8 viral load in the Kaposi's sarcoma lesions was performed during treatment using polymerase chain reaction. RESULTS: After initiation of HIV triple therapy with protease inhibitors, we observed six complete responses, two partial responses, and two patients with progressive disease. All patients had undetectable plasma HIV viral load within 2 months of treatment. Undetectable HHV-8 viraemia in PBMC occurred in seven out of eight patients with partial or complete response and in none of the progressive patients. A decrease or negation of HHV-8 viral load in Kaposi's sarcoma lesions was observed in two complete responders. CONCLUSION: Our results suggest that antiviral therapy with protease inhibitors are clinically efficient in HIV-associated Kaposi's sarcoma and that there exists a correlation between clinical response and negation of HHV-8 viraemia.

AIDS-Related Opportunistic Infections↗
PubMed1998

Lichen planus pemphigoides is a heterogeneous disease: a report of five cases studied by immunoelectron microscopy.

Lichen planus pemphigoides (LPP) is a rare and controversial disease. It is characterized by bullae arising on lichen planus papules and on uninvolved skin, subepidermal bullae in histology, and linear deposits of IgG and C3 along the basal membrane zone on immunofluorescence of peribullous skin. Our goal was to identify the localization of the target antigen in cases of LPP. Five patients diagnosed with LPP on clinical, histological and immunofluorescence criteria were explored by immunoelectron microscopy and immunoblot. Our results show that the target antigen in LPP is not unique. The localization of the immune deposits was consistent with a diagnosis of bullous pemphigoid in two cases, of cicatricial pemphigoid in two cases and of epidermolysis bullosa acquisita in one case. Our study supports the view that LPP is a heterogeneous condition in which lichen planus may induce different subepidermal acquired bullous dermatoses.

Adolescent↗
PubMed1997

Characterization of in vitro culture of HIV-negative Kaposi's sarcoma-derived cells. In vitro responses to alfa interferon.

We established long-term cultures from skin tumors of nine patients suffering from classical Kaposi's sarcoma (KS). Spindle cells obtained after enzymatic digestion were cultured on gelatin- or fibronectin-coated flasks in DMEM with 15% fetal calf serum, aFGF and heparin. Immunohistochemical staining was positive for MHC class I, laminin, type IV collagen, vimentin, alpha smooth muscle actin (20-40% of cells), caldesmon (20%), calponin (20-40%) and smooth muscle myosin (20-40%), and was negative for common leukocyte antigen, CD4, LFA1, CD34 and cytokeratin. Around 20% of cells up to the third passage in culture expressed the endothelial markers CD36, BMA 120 but were negative for UEA and Fc von Willebrand. Smooth muscle proteins were detected with immunoblotting. Using the polymerase chain reaction, human herpes virus 8 (HHV8) sequences were detected in primary cultures of three out of seven cell lines but were rapidly lost during in vitro passaging. KS-derived cells did not proliferate in serum-free medium, had a normal karyotype and did not grow in soft agar medium. Tumors formed in nude mice injected with KS-derived cells. The tumors were composed of mouse cells and were highly vascularized. Our results suggest that KS-derived cells are heterogeneous: the majority of cells have either a smooth muscle cell or a fibroblastic phenotype. Another minor cell compartment was composed of endothelium-derived cells. KS cells do not possess the characteristics of transformed cells in vitro and may be composed of polyclonal activated cells. Recombinant alpha interferon (rIFN) slightly inhibited the growth of KS-derived cells and increased the expression of MHC class I antigens. While cells were resistant to natural killer (NK) cell-mediated cytotoxicity, they became sensitive to rIFN-primed NK cells. Thus, the antitumor potential of rIFN against KS in vivo could result from immunomodulatory rather than from direct antiproliferative effects.

Animals↗
PubMed1997

Altered collagen of human pathological fibroblasts impairs the synthesis of fibronectin.

Human fibroblasts with mutated type I collagen have marked defective adhesive capacities on exogenous type I collagen and exogenous fibronectin in comparison to normal fibroblasts. This defective cell adhesion could be partly explained by the decreased level of cell surface receptors of the beta 1-integrin family, i.e., the alpha 2 integrin subunit for type I collagen and the alpha 5 integrin subunit for fibronectin, observed in pathological fibroblasts. However, it appeared that the presence of altered collagen interfered both with fibronectin biosynthesis and with its surface expression. Using a binding assay on immobilized fibronectin, we demonstrated that the mutated collagen had a weaker binding to fibronectin. In addition, the pathological fibroblasts plated on a mixture of normal exogenous type I collagen and fibronectin exhibited the same maximal level of adhesion as control fibroblasts. These results indicate that fibroblasts with the mutated collagen exhibit a decreased binding to normal fibronectin, a modification of synthesis and surface expression of fibronectin, and, finally, altered adhesive capacities.

Cell Adhesion↗
PubMed1997

Molecular analysis of clonality in Kaposi's sarcoma.

BACKGROUND: Kaposi's sarcoma is considered to be an angioproliferative disease associated with a novel herpesvirus (KSHV/HHV8), but the precise pathophysiology of the lesion remains unclear. The study of clonality in Kaposi's sarcoma using X linked DNA polymorphism has been difficult so far, because of a very strong prevalence of the disease in males. AIMS: To study the clonality of Kaposi's sarcoma lesions. METHODS: An assay based on a methyl sensitive restriction digest followed by polymerase chain reaction (PCR) amplification of the highly polymorphic human androgen receptor (HUMARA) gene was used. Tissues from Kaposi's sarcoma lesions and control tissues from the same patients were obtained from seven females, four with classic Kaposi's sarcoma and three with AIDS associated Kaposi's sarcoma. A cutaneous angiosarcoma was also analysed, for comparative purposes, and showed evidence of clonality after HpaII digestion. RESULTS: All patients were heterozygous for the HUMARA polymorphism and informative for analysis. In all patients, including four with a nodular form of Kaposi's sarcoma and more than 70% spindle cells in the lesion, a polyclonal pattern of inactivation could be demonstrated. CONCLUSIONS: The Kaposi's sarcoma lesion is first of all a polyclonal cell proliferation.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Detection of human herpesvirus 8 and human T-cell lymphotropic virus type 1 sequences in Kaposi sarcoma.

BACKGROUND: Ultrastructural studies have shown retroviral particles in Kaposi sarcoma (KS) unrelated to infection with the human immunodeficiency virus (HIV). Recently, DNA sequences from a new herpesvirus, human herpesvirus 8 (HHV-8), were detected in KS tissues. OBJECTIVES: To screen for the presence of HHV-8 sequences in patients with KS not related to HIV infection and correlate HHV-8 sequence detection and clinical staging and to screen for the presence of human T-cell lymphotropic virus type 1 (HTLV-1) sequences in the peripheral blood mononuclear cells (PBMCs) of such patients. DESIGN: Tumor and normal skin samples and PBMCs were investigated by polymerase chain reaction using primers for HHV-8 and HTLV-1 pX gag, pol, and env sequences. SETTING: Ambulatory or hospitalized patients from a university hospital associated with a research laboratory. PATIENTS: Thirty-one patients with KS not related to HIV infection (21 classic cases, 3 endemic cases, 1 case associated with Castleman disease, 4 homosexual men, 1 post-transplantation patient, and 1 patient taking corticosteroids). Stages involved included I (13 patients), II (8 patients), III (7 patients), and IV (3 patients). RESULTS: Human herpesvirus 8 sequences were found in 100% of KS specimens, 70% of distant normal skin specimens, and 42% of PBMC samples. The percentage of HHV-8 detection in PBMCs was higher in patients with KS stage III or IV than in patients with stage I or II. Human T-cell lymphotropic virus type I pX sequences were detected in 2 of 19 patients while gag, pol, and env test results were negative using polymerase chain reaction analysis. CONCLUSIONS: Our data suggest no significant association between HTLV-1 infection and KS. Detection of HHV-8 infected cells in normal skin samples from the majority of KS tissues, regardless of clinical staging, can be paralleled to the multifocal pattern of the disease. Human herpesvirus 8 detection in PBMCs could be related to the tumor burden.

Adult↗
PubMed1996

[Aggressive cutaneous T-cell lymphoma associated with the presence of Epstein-Barr virus. 2 cases].

INTRODUCTION: The factors of prognosis of the cutaneous T-cell lymphomas are less well known as those of the B-cell lymphomas and the role of the Epstein-Barr virus (EBV) is not yet definitively evaluated. CASE REPORTS: Two male patients aged 62 and 82 years had a mycosis fungoides with a lethal outcome. The first patient had mutilating facial tumors; the RNA m of EBV and the genome of EBV were demonstrated in the diseased skin. The second patient had an erythrodermic course with enlarged peripheral lymph nodes and circulating Sézary's cells; the genome of EBV was demonstrated by PCR in the diseased skin. DISCUSSION: The role of the EBV has already been demonstrated in peripheral aggressive T-cell lymphomas. In the mycosis fungoides, the EBV is associated with the lesions in 0 to 32 p. cent according to the published series. EBV associated T-cell lymphomas have a poor survival rate and the EBV infection may be associated with the expression of the multidrug resistant gene-1 (MDR-1) and the risk of a terminal hemophagocytosis. In our both patients the presence of the EBV in the lymphocytes of the skin lesions is also an argument in favour of the pathogenic role of the virus.

Aged↗
PubMed1995

Bacillary angiomatosis in HIV-infected patients: report of three cases with different clinical courses and identification of Rochalimaea quintana as the aetiological agent.

Three cases of cutaneous bacillary angiomatosis in HIV-infected patients are reported. They differed profoundly with respect to the extent of the lesions and the clinical course. In two cases, Rochalimaea quintana was identified by direct sequencing of the DNA amplified with the polymerase chain reaction (PCR), whereas an easy, rapid method based on the restriction length of polymorphism analysis of PCR products (PCR-RFLP) was used in the third case. This report illustrates the variations in clinical presentations and evolutive profiles in patients with bacillary angiomatosis, and confirms the causal role of R. quintana in this disease.

Adult↗
PubMed1993

Fanconi's anaemia associated with multicentric Bowen's disease and decreased NK cytotoxicity.

We report a patient with Fanconi's anaemia and multiple lesions of vulvo-anal Bowen's disease. She was thrombocytopenic and lymphopenic, and NK-mediated cytotoxicity was undetectable. The vulvar lesions did not contain papillomavirus DNA. In vitro studies showed a possible benefit from acitretin treatment on bone marrow stem cells. However, low-dose acitretin given for 14 months did not prevent the development of an anal squamous carcinoma. Acitretin therapy was, however, associated with a sustained rise in the platelet count.

Adult↗