Biomedical subjects
Hervé Bachelez
Publications and source records attributed to Hervé Bachelez.
Follow-up of the T-cell clonality in Sezary patients treated by extracorporeal photopheresis using a new assay: the immunoscope technique.
Sezary syndrome is a leukemic form of epidermotropic cutaneous T-cell lymphoma related to the malignant proliferation of clonal CD4+ T-cells. Extracorporeal photochemotherapy (ECP) may induce a transient improvement of the clinical signs but it's efficiency is discussed. In order to investigate the T-cell clonality in the peripheral blood of patients with Sezary syndrome and to monitor its evolution in 8 patients treated by ECP, we used the Immunoscope technique. In one patient, we observed a decrease of the T-cell clonality from 15.6% to 0%, paralleling a complete remission of the clinical disease with a disappearance of the circulating Sezary cells. In the other cases, the evolution of the relative frequency paralleled the clinical status of the patient. In 3 cases, we observed a quick-acting direct cytotoxicity of the association 8MOP + UVA on the T-cell clone present in the cellular product. Immunoscope technique appears to be an efficient assay to appreciate the amount of tumoral cells and monitor the evolution of the clonal component in Sezary syndrome.
Peripheral blood lymphocyte subset counts in patients with dermatomyositis: clinical correlations and changes following therapy.
Lymphocytopenia has been reported in patients with connective tissue diseases, including dermatomyositis (DM). However, the risk of infectious complications and the changes of lymphocytic subsets during treatment have been poorly investigated in these patients. We investigated the alterations of peripheral blood lymphocyte counts in patients with DM. A retrospective analysis was conducted in patients with an ascertained diagnosis of DM admitted from 1994 to 2000 in both departments of Dermatology of the Saint-Louis Hospital in Paris. All patients had a peripheral blood absolute lymphocyte count available before therapy. From an initial set of 63 patients, 47 were included in the study. The median absolute lymphocyte count was 888/mm(3) (range, 400-4,070). Low peripheral blood CD4+ and CD8+ T-cell and B-cell counts were consistent findings (median CD4+: 382/mm(3); CD8+: 211/mm(3); CD19+: 122/mm(3)). There was a significant increase in lymphocyte count after 1 month (p < 0.0001), 3-6 months (p = 0.001), and 6-12 months (p = 0.0005) of corticosteroid treatment. Infectious events, mainly pneumonia (PCP), occurred in 12 patients. Their initial lymphocyte count was lower than that of patients who did not develop infections (p = 0.0001). These results support the high prevalence of lymphocytopenia in patients with DM and emphasize the risk for opportunistic infections, mainly PCP, in these patients. Further studies are warranted to evaluate the risk/benefit balance of PCP prophylaxis in patients with DM and severe lymphocytopenia.
A prospective study on the evolution of the T-cell repertoire in patients with Sézary syndrome treated by extracorporeal photopheresis.
Sézary syndrome is a leukemic form of epidermotropic cutaneous T-cell lymphoma related to the malignant proliferation of clonal CD4(+) T cells. Extracorporeal photochemotherapy may induce a transient improvement of the clinical signs, but its efficiency is discussed. To investigate the frequency of the T-cell clone in the peripheral blood of patients with Sézary syndrome and to monitor its evolution in patients treated using extracorporeal photopheresis or chemotherapy, we used the immunoscope technique. In one patient, we observed a decrease of the relative frequency of the clone from 15.6% to 0%, paralleling a complete remission of the clinical disease and a disappearance of the circulating Sézary cells. In the other cases, the evolution of the relative frequency paralleled the initial improvement of the clinical status and the absence of long-term efficiency in patients treated with extracorporeal photopheresis or chemotherapy. We observed a quick-acting direct cytotoxicity of the association 8MOP + UVA on the T-cell clone. The immunoscope technique appears to be an efficient tool to appreciate the amount of tumoral cells and to monitor the evolution of the clonal component in the Sézary syndrome.
B-cell lymphomas involving the skin associated with hepatitis C virus infection.
BACKGROUND: A role for hepatitis C virus (HCV) infection has been suggested in the pathogenesis of non-Hodgkin lymphomas (NHL). AIM: To evaluate the characteristics of cutaneous lymphomas occurring in HCV-infected patients, and to investigate the hypothesis of a direct infection of malignant cells. METHODS: Three patients showing a positive serology for HCV and a cutaneous lymphoma were studied. Analysis of HCV replication was performed using reverse transcriptase-polymerase chain reaction. The presence of HCV RNA was also assessed in biopsies from lesional skin and in a lymph node in one case. Genotype characterization was carried out on the basis of LiPA genotyping assays using viral genomic amplification products. RESULTS: Cutaneous NHL occurred in patients with chronic and replicative HCV infection, and exhibited a B-cell phenotype (one diffuse large B-cell lymphoma, one follicular lymphoma, and one marginal zone B-cell lymphoma). All patients were male; two of them were former intravenous drug abusers, while the HCV contamination route was unknown in the third. The search for HCV RNA in the skin and in lymph nodes yielded negative results. HCV genotypes were 1b in two cases and 3a in one case. CONCLUSION: These results show that a subset of B-cell cutaneous NHL is associated with a replicative HCV infection and suggest that HCV is not involved in lymphomagenesis through a direct infection of malignant cells. The ability of HCV to trigger a chronic B-cell lymphoproliferation could represent another mechanism, while a fortuitous association cannot be excluded.