PubMed Health⌕ Search

Biomedical subjects

H Bachelez

Publications and source records attributed to H Bachelez.

48 records · Page 3Linked to original sources
PubMed1995

Expression of V beta gene segments by Sezary cells.

The T-cell receptor V beta repertoire expressed by Sezary cells was determined in a series of 16 patients whose samples have been shown to contain a majority of tumor cells. By using anti-V beta monoclonal antibodies, polymerase chain reaction analysis of expressed V beta, and, in selected cases, nucleotide sequencing, we have shown that the expressed V beta segments belong to five V beta families (V beta 5, V beta 6, V beta 8, V beta 13, and V beta 18), which contain a large fraction of the T-cell receptor V beta repertoire and do not share significant similarities in complementary determining region 4. V beta segments from these five families were also found to be strongly expressed by CD4 + CD7- peripheral blood cells obtained by fluorescence-activated cell sorting from two healthy donors. The diversity of the V beta repertoire expressed by Sezary cells appears to be similar to that expressed by circulating non-neoplastic T cells. These data do not support the hypothesis that a common superantigen is involved in the initiation of this form of cutaneous T-cell lymphoma.

Antigens, CD↗
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↗
PubMed1995

Detection of clonal T-cell receptor gamma gene rearrangements with the use of the polymerase chain reaction in cutaneous lesions of mycosis fungoides and Sézary syndrome.

BACKGROUND AND DESIGN: We used the amplification of junctional V (variable)-J joining sequences of the rearranged T-cell receptor gamma (TCR gamma) genes by polymerase chain reaction for rapid and sensitive detection of a clonal T-cell population in a total of 51 skin specimens obtained from 45 patients with mycosis fungoides, five patients with Sézary syndrome, and 29 patients with chronic inflammatory dermatoses. RESULTS: A clonal TCR gamma gene rearrangement was present in all tumors (3/3, 100%) and in most infiltrated plaques (16/22, 73%) and erythrodermas (10/12, 83%). In the patch stage, a clonal subset was found in more than half of the cases (8/14, 57%), whereas no clonality was observed in the controls. We also amplified the V-J sequences of the Igh locus coding for the heavy chain of immunoglobulins, without evidence of clonal rearrangement. These data were compared with those from in situ immunophenotypic analysis. Moreover, by using the same assay with successive dilutions of standard clonal T-cell DNA, a semiquantitative study of the T-cell clone was carried out in some cases. The highest ratios of clonal DNA were observed in advanced stages. CONCLUSIONS: These data validate polymerase chain reaction V gamma-J gamma as a rapid, sensitive tool that can be used in the routine analysis of clonality in cutaneous lesions of mycosis fungoides and in the early diagnosis of mycosis fungoides and Sézary syndrome. Semiquantitative studies suggest that the malignant T-cell clone follows a selective process during the course of the progressive form of mycosis fungoides.

Clone Cells↗
PubMed1992

TCR gamma delta bearing T lymphocytes infiltrating human primary cutaneous melanomas.

In situ immunophenotypic studies show that tumor infiltrating T lymphocytes from six of 11 fresh cutaneous primary melanomas tested contain T-cell receptor gamma delta expressing cells whereas those from 8 metastatic melanomas did not. In three cases these cells represent an unexpectedly high proportion of the lymphocytic infiltrate, ranging from 15 to 25%. This elevated percentage is maintained when tumor infiltrating lymphocytes are propagated in vitro for 2 or 3 weeks in the presence of recombinant interleukin 2 and autologous tumor cells. Functional studies reveal that gamma delta lines or clones developed from lymphocytes infiltrating primary melanoma display, in addition to their natural killer-like activity, a potent autologous tumor cell cytotoxic activity that does not seem to be restricted by major histocompatibility complex gene products.

Humans↗
PubMed1990

Identification of a novel 110-kilodalton structure expressed on a subset of T cell receptor-gamma delta-bearing cloned lymphocytes.

A small percentage of circulating CD3+ cells express a heterodimeric gamma delta receptor. Most of these cells do not express the surface marker CD4 and only a fraction of them bear CD8 molecules. The specificity and function of TCR-gamma delta are unclear. We obtained a murine mAb produced against an IL-2-dependent human T cell clone defining a novel molecule sTA which is not expressed on resting human peripheral blood CD3+ cells but strongly expressed on a fraction of TCR-gamma delta-bearing clones. Like receptors for growth factors such as IL-2, the sTA Ag is present on clones and cell lines according on the cell cycle. SDS-PAGE analysis of sTA immunoprecipitates from 125I-labeled sTA+ clone lysate demonstrated a single band of molecular mass 110 kDa under reducing conditions. Triggering with anti-sTA mAb did not result in [Ca2+]i mobilization of sTA+ clones. Additionally, the presence of anti-sTA did not alter the cytotoxicity of these sTA+ clones neither against tumor target cells nor against specific PHA blast cells. Interestingly, due to the fact that most sTA+ clones fail to proliferate in response to CD3 triggering, it appears that sTA may serve as a useful marker to study the functional heterogeneity of TCR-gamma delta expressing cells.

Antibodies, Monoclonal↗
PubMed1990

Infiltrating lymphocytes in benign and malignant naevomelanocytic lesions.

Cutaneous melanocytic tumors include benign (naevi) and malignant (melanoma), potentially metastatic lesions. In this report, we show that infiltrating lymphocytes from benign tumors may be expanded in vitro as TIL from melanoma in the presence of autologous tumoral cells and recombinant IL2. Moreover it seems that TIL from primary cutaneous benign or malignant lesions more frequently express the T-cell receptor gamma delta than TIL from metastatic melanoma. Otherwise, a gamma delta + line and a gamma delta + clone extracted from a primary cutaneous melanoma exhibit a specific non MHC-restricted cytotoxic activity against autologous tumor cells. This is the first report of a TCR gamma delta + T lymphocyte cytotoxic activity against a human solid cutaneous tumor.

Cytotoxicity, Immunologic↗
PubMed1989

[Treatment of Kaposi's disease].

Several clinical, epidemiological and immunological data support the opportunistic nature of Kaposi's disease. Although the physiopathology of the disease is unknown, its characteristics, and particularly its immunological dependence, have repercussions on treatment which must avoid making the immunological process worse, especially since the proliferation is rarely life-threatening. Recent therapeutic innovations, such as alpha interferon, have failed to bring the expected results which are disappointing in the form associated with the acquired immunodeficiency syndrome. In the classical form of the disease radiotherapy and chemotherapy provide a satisfactory improvement without any side-effect that might threaten the patient's life.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Recent physiopathological insights in cutaneous lymphocytic infiltrates.

The spectrum of benign cutaneous lymphocytic infiltrates (CLI) includes a variety of entities which are classified on the basis of clinicopathological findings, and of the phenotype of the predominant lymphocytic subset among the skin infiltrate. Major concern has been recelntly given to the clonality status of CLI by using highly sensitive assays based on the PCR amplification of TCR/Ig loci. These studies allowed the characterisation of clonal benighn cutaneous lymphocytic expansions. Other studies have shown evidence of oligoclonal patterns in HIV-associated CD8 cutaneous pseudolymphomas, and functionnal studies of the skin infiltrate further showed that an antigen-driven mechanism was involved in the pathogenesis of this latter entity. Finally, the knowledge in the field of CLI has been improved by the identification of antigens associated with skin-homing properties such as the so-called. Cutaneous Lymphocyte-associated Antigen (CLA) whicis expressed at the surface of most memory T cells infiltrating the dermis in inflammatory conditions.

Humans↗