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J Viac

Publications and source records attributed to J Viac.

At least 73 records · Page 4Linked to original sources
PubMed1990

Immunocompetent cells and epithelial cell modifications in molluscum contagiosum.

We studied lesions of molluscum contagiosum with a panel of monoclonal antibodies to determine the phenotype of infiltrating cells and antigen modifications of infected keratinocytes. Our data indicate (1) a complete lack of immunocompetent cells in the viral lesions, and simultaneously a loss of B2-microglobulin reactivity by molluscum bodies, a cellular activation of EGF and transferrin receptors and expression of CD36 antigen of these bodies; (2) a moderate infiltrate of activated T cells and monocytes in the underlying epidermis; (3) an increase of Langerhans cell density and a CD36 expression by the surface of upper layer keratinocytes in the perilesional epidermis.

Epithelium↗
PubMed1990

Expression of human epithelial characteristics in late passages of interspecific somatic hybrids derived from normal and hand wart keratinocytes.

The expression of epithelial features has been investigated from the 9th to the 30th passage in cells derived from the fusion of mouse 3T3.4E cells with normal or hand wart human keratinocytes. These cells stratified and grew either on plastic or collagen substrate without modifications. Such growth characteristics are similar to those observed in the epidermis. The doubling time of hybrid cells is nearer to that of 3T3.4E than to that of keratinocytes. Some epithelial markers were detected by immunofluorescence staining. Bullous pemphigoid antigen characteristic of the basal keratinocyte was detected, and cytoplasmic antigen of basal cells was positive with BL7 monoclonal antibody. Among the antigens of the suprabasal cell layers of the epidermis, the pemphigus antigen was present in all hybrids; epidermal keratins recognized by the monoclonal antibodies KL1 and KL2 were detected in wart hybrids up to the 9th passage. When hybrids were cultured in delipidized serum or in methylcellulose, few cells (less than 10%) reacted with KL2. Karyological analysis revealed both murine acrocentric and human submetacentric chromosomes. Thus, hybrid cells obtained from normal and wart keratinocytes were new cell types with a phenotype between keratinocytes and 3T3.4E cells.

Animals↗
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

Comparative expression of bullous pemphigoid antigens in normal human epidermis and cultured keratinocytes.

A heterogeneity of the bullous pemphigoid (BP) antigen initially described as a 220- to 240-kDa polypeptide doublet expressed in normal human skin was recently demonstrated. The aim of our study was to compare the heterogeneity of BP antigen by the immunoblotting technique in extracts of both human epidermis and keratinocyte cultures. Extracts of epidermal tissues obtained from plastic surgery skin samples and secondary keratinocyte cultures were analyzed for their immunologic content defined by 30 BP sera. Twenty-six out of 30 tested sera showed similar binding reactivities with one or several polypeptide bands in both extracts. These sera defined seven antigens of molecular weights ranging from 240 to 97 kDa. Three groups of sera reacting with three, two, or only one antigen could be distinguished in which 180, 200, and 220 kDa polypeptides represented the major BP antigens both in vivo and in vitro. The binding reactivity of most immunofluorescent negative sera demonstrated the sensitivity of the immunoblotting technique to evidence the heterogeneity of BP antigens and antibodies. Keratinocyte cultures represent a reproducible substrate for such analysis and offer a standardization attempt in comparative investigations in BP.

Aged↗
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

Cyclosporin A inhibits directly in vivo keratinocyte proliferation of living human skin.

A direct in vivo antiproliferative effect of cyclosporin A (CsA) on human epidermal keratinocytes (EK) grafted onto nude mice was evaluated. Using pulse-labeling of 5-bromo-2'-deoxyuridine (BrdU), a thymidine analogue incorporated into the nuclei of DNA-synthesizing (S-phase) cells, the antiproliferative effect of CsA was revealed as a decrease in the number of BrdU-positive human EK grafted onto nude mice receiving a daily subcutaneous injection of 50 mg/kg of CsA. The blood level of CsA in the treated mice, evaluated by a radioimmunologic assay, was 679 +/- 501 ng/ml (n = 3). Using an antibody to leukocyte common antigen, it was shown that no human lymphocytes were present in the grafted skin. Therefore, this antiproliferative effect of CsA on human EK seems to be due to a direct effect on EK rather than to lymphocyte regulation.

Animals↗
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

Expression of an estrogen receptor-associated protein (p29) in epithelial tumors of the skin.

p29 is a cytoplasmic serine phosphoprotein of 29 kD MW, closely linked to estrogen receptors. In this work we studied the expression of p29 protein in normal human skin and a group of cutaneous benign and malignant tumors by using a monoclonal antibody (ERD5) that specifically recognizes p29. In normal skin, p29 reactivity was observed in epidermal and some adnexal keratinocytes, as well as in smooth muscle cells of dermal arterioles and arrector pili muscles. p29 was also detected in most, but not all, epithelial tumors studied. The expression of p29 was generally stronger in the more differentiated (keratinized) normal and neoplastic keratinocytes; however, no correlation could be noted between immunochemical staining for p29 and either benignity of the lesion or sex of the patient considered. Whereas, in breast cancer, the expression of p29 is reported to correlate with endocrine response, the precise relationship between epithelial tumors of the skin and the action of estrogens remains to be elucidated.

Adult↗
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↗
PubMed1988

Filaggrin expression in normal and pathological skin. A marker of keratinocyte differentiation.

Filaggrin is a basic, histidine-rich protein synthesized by cells of keratinizing epithelia, that subserves major physiological functions in maturating epidermis. Its precursor, profilaggrin, constitutes a major component of kertohyalin granules. In this work the expression of profilaggrin/filaggrin was studied in 140 specimens of normal human adult and fetal skin, cultured epithelia before and after allo- and xeno-grafting, and several cases of keratinization disorders and tumours. An avidin-biotin-alkaline phosphatase technique was applied on deparaffinized tissue sections, by using a specific monoclonal antibody (AKH1) to profilaggrin/filaggrin. The results show that the expression of profilaggrin/filaggrin is variously altered in keratinization disorders, whereas in epithelial proliferations it seems to decrease with an increasing degree of dedifferentiation of the tumour. Therefore the expression of these antigens can be considered to be a sensitive marker of maturation of normal epidermis and provides a new tool for the study of differentiation of the surface epithelium in skin diseases.

Fetus↗
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

Expression of neural-tissue markers (S-100 protein and Leu-7 antigen) by sweat gland tumors of the skin. An immunohistochemical study.

The expression of two immunohistochemical markers of neural tissue and of cutaneous sweat glands (S-100 protein and Leu-7 antigen) was studied in a group of cutaneous epithelial, mostly glandular, tumors. These antigens were detected only on sweat gland neoplasms showing both types (eccrine and apocrine) of differentiation. These results suggest that antibodies to S-100 protein and to Leu-7 antigen have a limited value in the distinction between eccrine and apocrine tumours, but they may serve as a useful adjunct for the confirmation of the glandular differentiation of cutaneous epithelial tumors.

Antigens, Differentiation, T-Lymphocyte↗
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

Involucrin expression in keratinization disorders of the skin--a preliminary study.

We have studied the expression of involucrin in a variety of keratinization disorders, mostly of genetic origin using an avidin-biotin-peroxidase technique. In normal human epidermis 25% of the living epidermis was labelled. The diseases studied fell into two groups. Diseases with greatly increased involucrin staining including collodion baby (38%), Darier's disease (49%), Flegel's disease (56%), erythrokeratoderma variabilis (60%), epidermal naevus with epidermolytic hyperkeratosis (45%) and congenital bullous (58%) and non-bullous (44%) ichythyosiform erythroderma; and diseases with normal or slightly increased staining, including ichthyosis vulgaris (27%), X-linked ichthyosis (25%), confluent and reticulate papillomatosis (27%) and simple epidermal naevus (28%). These results demonstrate that involucrin expression is altered in some keratinization disorders and suggest that in such conditions cellular functions other than keratin metabolism are also affected.

Humans↗
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

Ultrastructural quantitation of desmosome and differentiation-related keratinocyte membrane antigen.

The keratinocyte membrane antigen KM 48 was defined by a new monoclonal antibody obtained after mouse immunization with normal human epidermal cell suspension. Specific reactivity of the antibody with desmosomal regions of keratinocyte cell membrane was demonstrated by immunoelectronmicroscopy. Langerhans cells, melanocytes, and indeterminate cells did not express the KM 48 antigen. Immunogold labelling permitted ultrastructural quantitation of KM 48 antibody binding on keratinocytes from various epidermal layers. A gradual increase in desmosome-related KM 48 antigen expression accompanied differentiation of keratinocytes during their transit from basal to granular layer. Distribution of the antigen on individual cells was uneven. The upper pole of a keratinocyte facing overlying more differentiated cells was always found to be laden with an immunogold marker about twice that of the opposite, lower surface of the cell. The results support the previous reports on gradual development of desmosomes during epidermal cell maturation and open up new possibilities for keratinocyte differentiation studies. They also underline the virtues of the immunogold-labelling method used for cell-surface antigen tracing and quantitation.

Adolescent↗