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Y Chardonnet

Publications and source records attributed to Y Chardonnet.

At least 73 records · Page 4Linked to original sources
PubMed1989

Antigenic immunostaining patterns in somatic hybrids of human HeLa cells and mouse fibroblasts 3T3.4E propagated in conventional medium and delipidized serum.

Somatic cell hybrids were obtained with electric pulse by fusion of human epithelial HeLa cells derived from a carcinoma of the uterine cervix and mouse fibroblasts 3T3.4E, deficient in thymidine kinase. Hybrids were selected and propagated in HAT media; some experiments were carried out in medium with delipidized serum. The hybrid cells were characterized by indirect immunofluorescence with a biotin-streptavidin system using a panel of nine monoclonal antibodies specific for membrane and cytoplasmic antigens of parental cells: intermediate filaments (keratins and vimentin), HLA class 1 (beta 2-microglobulin), cell activation (EGF and transferrin receptors) and cellular adhesion (fibronectin and laminin). All of these antigens were expressed in HeLa cells cultured in conventional medium or with delipidized serum. Conversely mouse fibroblasts contained only vimentin, fibronectin and laminin. All the parental antigens were present in first passage hybrid cells cultured in conventional medium. Vimentin, fibronectin and laminin were maintained in fourth passage hybrids whereas keratins, beta 2-microglobulin, EGF and transferrin receptors were no longer detected. When propagated in medium with delipidized serum, hybrid cells re-expressed these antigens after 5 days of culture. These findings suggest that the reexpression of HeLa cell antigens in hybrid cells was related to deficiency in vitamin A.

Animals↗
PubMed1989

Ultrastructural characteristics of hybrids derived from normal and hand wart keratinocytes after serial passages.

Somatic hybrids realized between mouse fibroblasts 3T3.4E and normal human keratinocytes or hand wart keratinocytes were examined from the 6th to the 30th passages by scanning and transmission electron microscopy. Whatever the passage, hybrid cells showed a fibroblastic morphology but, as keratinocytes, they had the capability to stratify. Branched mitochrondria were observed in hybrids whereas normal mitochondria were present in mouse fibroblasts. In human keratinocytes, most of the mitochondria were normal but sometimes few of them were branched. In wart hybrids heterogeneous nucleoli were detected instead of normal nucleoli in normal keratinocyte hybrids, 3T3.4E cells and human keratinocytes.

Animals↗
PubMed1989

Filaggrin expression in cutaneous and mucosal human papillomavirus induced lesions.

A series of 32 human papillomavirus induced lesions derived from epidermis and mucosa was studied for the modulation of filaggrin-profilaggrin (F-PF) expression according to the degree of virus infection as compared to normal skin and mucosa biopsies. This investigation was carried out on frozen sections using indirect immunofluorescence for filaggrin detection and group specific viral antigen and by in situ hybridization with biotinylated probes for viral DNA detection and typing. The 9 cutaneous warts showed an increase of F-PF expression in upper layer cells as compared to normal epidermis, which could be related to the high production of virus (viral antigen and HPV types 1 or 2). The 5 condyloma acuminata displayed also an enhanced expression of these components which was located in several upper layers but virus infection was confirmed in 2 of them with HPV types 6, 11 or 16. The 6 laryngeal papillomas exhibited a granular reactivity pattern for F-PF in suprabasal cell layers with an increase in the upper layers; viral antigen was found in 4 cases and HPV DNA types 6, 11 or 16 were detected in 4 specimens. Conversely among 12 cervical intraepithelial neoplasia, F-PF was expressed only in very superficial layers in few cases, without any correlation with the DNA detection (6, 11 or 16, 18). Taken together these data are suggestive of an intense expression of F-PF in benign lesions which can replicate the virus and a discrete or an absent expression of these components in premalignant or malignant lesions.

Adult↗
PubMed1989

Distribution of an estrogen receptor-related protein (P29) in normal skin and in cultured human keratinocytes.

A monoclonal antibody, ERD5, which recognizes a 29Kd phosphoprotein associated with human estrogen receptor of myometrium was used to study the expression of this protein in normal skin and in cultured human keratinocytes. By indirect immunofluorescence, both in vivo and in vitro keratinocytes showed a variable cytoplasmic staining which increased with cell differentiation. SDS gel electrophoresis of soluble extracts of cultured keratinocytes and normal epidermis showed that P29 was a minor protein. Immunoblot analysis demonstrated that ERD5 strongly reacted only with a 29Kd polypeptide band without any cross-reactivity. These data suggest that keratinocytes might be estrogen sensitive like other cells in which P29 has already been located. The exact role of this protein in the keratinocyte differentiation process and its relationship with estrogen receptors remain to be elucidated.

Adolescent↗
PubMed1989

[Warts and epidermoid carcinoma after renal transplantation].

UNLABELLED: Kidney transplant recipients suffer in the long-term from several cutaneous disorders linked to the transplantation. We had the opportunity to observe several patients presenting with pre-epitheliomatous keratoses and cutaneous carcinomas associated with warts. We report herein on five cases that were subjected to a clinical, histological and virological study. Material and methods. Clinical and histological report. The patients were referred to use by the Kidney Transplantation Department of the Ed. Herriot Hospital (Lyon). They were examined clinically by one of us (S.E.). Virological studies. These were performed on warts, keratoses, keratoacanthomas and squamous cell carcinomas. Human papillomavirus (HPV) antigen was detected by indirect immunofluorescence using rabbit antibodies raised against group-specific HPV antigen; viral DNA was detected by in situ molecular hybridization using biotinylated probes of types 1a, 2a, 16, 18 in all cases and type 5 in 14 lesions under stringent conditions. DNA-DNA hybrids were revealed by an alkaline phosphatase enzymatic system. RESULTS: (a) Clinical data are summarized in table I (see fig. 1-5). (b) Histological examination (fig. 6-9) showed either unequivocal squamous-cell carcinoma or keratoacanthoma . The overall architecture of the lesions was reminiscent of keratoacanthoma; however the lower limit was frequently not sharply demarcated; in that area, cells contained large basophilic nuclei exhibiting atypical features and numerous mitoses. The majority of lesions had an histological appearance reminiscent of warts (table III), with upper epidermal keratinocytes being vacuolized and containing basophilic (c) The results of virological studies (fig. 10-13) are summarized in table III. HPV group specific antigen was detected merely in 5 out of 33 lesions; in contrast, in situ molecular hybridization showed that 25 out of 33 lesions contained HPV DNA, with 14 of them containing the potentially oncogenic types 16 and 18. Only 2 lesions were positive with the prove HPV 5. Discussion. The overall incidence of cancers in Kidney transplant recipients (3 p. 100) is about 100 times higher than in control populations (17). Cutaneous carcinomas account for about 50 p. 100 of cancers. This incidence increases with time after transplantation and sun-exposure. The delay on onset of cutaneous malignancies is relatively long (4 to 7 years) (6,7) and becomes longer with a decreasing age of the patients at the time of transplantation, as can be noted in our cases. Apart from Blohme (1), most authors have reported a prevalence of squamous over basal-cell carcinoma. None of our patients presented basal-cell carcinoma.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1989

[Malpighian epithelia infected by DNA viruses and Langerhans cells].

Malpighian epithelia exhibit an immune surveillance through Langerhans cells (LC) against the DNA viruses, which induce various epithelial lesions, mainly on the skin, conjunctiva, mouth, uterine cervix. These viral infections are usual during childhood. The most common DNA viruses are: adenoviruses (more than 40 types), human papillomaviruses (HPV, more than 50 types) and Herpes viruses (herpes simplex type 1 and 2, varicella and Zooster, Epstein-Barr virus). Different clinical aspects are observed (exanthema, erythema, eruption, papillomas, vesicle, bullous) are well as histological signs. All of these viruses are replicating in the nuclei of epithelial cells which show eosinophilic inclusions and finally cell degeneresence with a typical aspect for each virus such as koilocyte for HPV infection. These lesions are commonly infiltrated with T lymphocytes; the intensity of the local cellular immune response varies with the lesion. LC are reduced in infected epithelia; they are sometimes found in conjunctive tissues and their morphology can be altered; their role in antigen presentation to T lymphocytes has only been demonstrated in herpes simplex virus infections. Profound modifications of membrane antigens of epithelial cells (loss of HLA class 1 antigen) might contribute to the disappearance of LC or to their functional inability. Most of the DNA virus infections are inapparent, benign and transient. However some lesions can evolve towards malignancy; this progression depends on the oncogenic potential of the viruses (such as HPV types 16 and 18 or herpes simplex virus type 2) associated to a local or a general immune deficiency of the patient as well as to other exogenous factors (UV for example).

Adenoviridae↗
PubMed1987

Virus expression. EGF and transferrin receptors in human papillomas.

Thirty five non regressing cutaneous and mucosal human papillomas were studied for the expression of EGF and transferrin receptors by indirect immunofluorescence on frozen sections. The lesions were also examined for the presence of human papillomavirus (HPV) DNA by in situ-hybridization with biotinylated probes and viral capsid antigen. The mapping of EGF and transferrin receptors was modified in cutaneous lesions with drastic viral cytopathic effects and was enhanced in mucosal lesions mainly in laryngeal papillomas, which are poor virus producers. The greatest increase in EGF and transferrin receptor reactivity was observed in the group of mucosal lesions in which viral DNA was more frequently detected than viral antigen. This suggests that viral DNA may play a role in basal cell stimulation. Moreover some of these lesions with dense inflammatory reactions showed DR antigen expression by epithelial cells. Our findings indicate that epithelial cell activation in papillomas might be modulated by other factors than HPV such as mediators of the local immune response.

Adolescent↗
PubMed1987

Epithelial expression of HLA-DR antigens in laryngeal papillomas with a dense inflammatory reaction.

Thirty six laryngeal papillomas taken from 11 children and 10 adults were investigated with an indirect immunofluorescence technique for the occurrence of T cell subsets, Langerhans cells and HLA-DR antigen using specific monoclonal antibodies. A mild local cellular immune response was preferentially associated with juvenile laryngeal papillomas, whereas a more intense inflammatory reaction with T8 cell infiltration and large amounts of Langerhans cells in the chorion and the epithelium was observed in adult lesions. Some lesions either from adults or children characterized by high densities of lymphoid and dendritic cells exhibited the expression of DR antigen by epithelial cells. This result may suggest either a role of lymphokines released by activated T cells or a direct effect of viral infection on epithelial cells inducing DR antigen in laryngeal papillomas.

Adult↗
PubMed1987

A method of in situ molecular hybridization applied to the study of viral papillomas in man.

Thirty nine papillomas and 14 precancerous lesions, from skin and mucosa were studied for the presence of human papillomavirus (HPV) infection on frozen sections or on paraffin embedded sections by comparison of 2 methods: (1) Detection of group specific viral antigen by immunohistochemical techniques with a rabbit antiserum raised to highly purified virus dissociated by SDS (sodium dodecylsulfate) and heating: (2) detection of viral DNA by an in situ molecular hybridization technique with biotinylated probes. In non-stringent conditions of hybridization (20 p. 100 formamide, Tm = -33 degrees C) viral DNA sequences were more frequently detected (85%) than viral antigen (32%). They were detected in a high proportion of cutaneous and mucosal papillomas as well as in precancerous lesions. They were found in 7 out of 8 biopsies from Bowen's disease and bowenoid papulosis, which were viral antigen negative. Under stringent conditions (50 p. 100 formamide, Tm = -12 degrees C) in situ hybridization allowed typing of HPV. Identical results were obtained in most lesions using in situ hybridization and the Southern technique. Some discrepancies were observed in mucosal lesions, which could be due to the presence or absence of infected foci in the different fragments. Thus, with in situ hybridization it is possible to evaluate the risk of evolution towards malignancy when potentially oncogenic types are present in the biopsies. In the absence of viral DNA in lesions, complementary methods should be used (detection of viral DNA with Southern technique or detection of RNA transcripts).

Adolescent↗
PubMed1986

Laryngeal papillomas: local cellular immune response, keratinization and viral antigen.

Various parameters of the local cellular response have been studied in 16 laryngeal papillomas from ten patients with recurrent papillomas as well as normal control laryngeal and tracheal tissue by indirect immunofluorescence on frozen sections using monoclonal antibodies specific for T-cell subsets, Langerhans cells (LC) and HLA-DR antigens. Keratinization was investigated with a monoclonal antibody KL1 recognizing an acidic 56.5 Kd keratin, which is a marker of suprabasal cells in stratified squamous epithelium and is absent from the basal layer. The presence of viral antigen was detected with a rabbit antiserum raised against SDS-dissociated purified virus. A mild inflammatory response was observed in most biopsies. Cytotoxic/suppressor T-cells were the predominant cells found in the lesions. Compared with normal epithelium, the number of LC was dramatically reduced in the papillomatous epithelium. High densities of HLA-DR-positive cells were found mainly in the corium. The keratinization process was disturbed in most specimens in that both basal and suprabasal compartments reacted positively with the KL1 monoclonal antibody. Viral antigen was present in the nucleus of very occasional epithelial cells in some samples.

Adolescent↗
PubMed1986

Langerhans cells in human warts.

Seventy-six warts (15 plantar, 38 hand, 16 miscellaneous and seven anogenital lesions) taken from 55 patients, were studied by indirect immunofluorescence with monoclonal antibodies specific for T-cell subsets, Langerhans cells (LC) and HLA-DR antigen. The results were related to the presence of viral antigen. Approximately 80% of the lesions showed an infiltrate. Only 19 lesions contained helper/inducer or suppressor/cytotoxic T cells. The distribution of LC was abnormal in 65% of biopsies which contained LC in the dermis, and 29% were devoid of LC in the epidermis. Many lesions had reduced numbers of LC in the epidermis. The disappearance of LC from the epidermis was related to the presence of viral antigen, but not to the presence of particular T-cell subsets. Infiltrating cells were sometimes HLA-DR-positive, whereas basal cells did not express HLA-DR antigen, irrespective of the density of the infiltrate.

Adolescent↗
PubMed1986

Expression of epidermal differentiation antigens in cultures of interspecific somatic hybrids (human keratinocytes X mouse fibroblasts 3T3-4E).

Interspecific somatic hybrids have been prepared by fusion of human epidermal cells with mouse fibroblasts 3T3-4E using PEG 4000. Expression of epidermal differentiation antigens (bullous pemphigoid antigens, BP, keratin subsets 55-57 k and 67 k), markers of basal and suprabasal cells, were studied by immunocytochemistry for 10 passages. These markers were detected in the hybrids early after fusion, indicating that cells from both compartments were able to fuse with 3T3-4E cells. However, the hybrids expressing high molecular weight keratins were no longer detected after 7 days in primary cultures and serial passages, whereas those expressing BP antigens and vimentin persisted. Low molecular weight keratins 52 K and 50 K were detected by SDS-PAGE at the second passage in precipitates formed between labeled hybrid lysates and total keratin rabbit antiserum. Karyotype analysis showed mainly murine chromosomes and a submetacentric human chromosome between the 6th and the 10th passage.

Animals↗
PubMed1986

Sequential changes in cytomegalovirus antigenic pattern during infection of renal transplant patients.

Changes in the antigenic pattern of cytomegalovirus occurring during the course of infection were studied in two renal transplant patients. The virus was isolated several times from each patient. After two to five passages in vitro, the immune precipitate formed either with guinea-pig antiserum raised to Davis reference strain, or with human serum taken from the same patient during the acute phase of the infection, was analysed by SDS-polyacrylamide gel electrophoresis. Isolates from each patient showed a slightly different antigenic pattern with both human and experimental antisera. These differences possibly reflect modulation of the expression of proteins during the course of viral infection in the patients and during adaptation to cell culture in vitro.

Antigens, Viral↗
PubMed1984

[Interspecies somatic hybrid cultures from human epidermal cells and 3T3-4E mouse fibroblasts].

Interspecific somatic hybrids were obtained by fusion of adult human epidermal cells with Mouse fibroblasts 3T3-4E, deficient in thymidine kinase. These hybrids were identified by their morphology and by the presence of markers from the parental cells. Some characters of keratinocytes such as keratin subunits 50 and 51 K were present in primary cultures and disappeared after serial passages, whereas bullous pemphigoid basement membrane zone antigens persisted for at least 20 passages. At the 7th passage, a metacentric chromosome, and more often a submetacentric chromosome, presumably of human origin, were observed in some cells.

Animals↗