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Biomedical subjects

Y Chardonnet

Publications and source records attributed to Y Chardonnet.

131 records · Page 8Linked to original sources
PubMedDate not supplied

[Interactions of Shope papilloma virus with SV40 in adult domestic rabbit cell lines derived from normal skin or from Shope papilloma virus infected skin (author's transl)].

Three cell lines from adult domestic rabbit are infected with SV40: LP 17 and LP 45 derived from normal skin and LP 42 PS derived from skin infected for 24 h with Shope papilloma virus. The fibroblastic morphology of the cultures is not changed. SV40 is not recovered and T antigen is only detected in LP 42 PS cell line after 29 passages. To know if Shope papilloma virus facilitates penetration of SV40, cultures of LP 45 are first infected with Shope papilloma virus for 2 h and for 24 h, then superinfected with SV40. There is no cellular alteration, and T antigen induced by SV40 is only detected in cells pretreated for 24 h with Shope papilloma virus, after 20 passages. When cultures LP 45 are infected with Shope papilloma virus neutralized with a high titer antiserum and superinfected with SV40, T antigen is not detected. Superinfected cells containing specific SV40 T antigen do not induce tumors either in new born hamsters or in rabbits but they are able to grow in colonies in soft agar. LP 42 PS cell line and LP 45 cells infected with Shope papilloma virus for 24 h containe Shope papilloma virus genome which is able to modify the permissivity of rabbit cells to SV40.

Animals↗
PubMedDate not supplied

Immunohistochemical studies on c-erbB-2 oncoprotein expression in paraffin embedded tissues in invasive and non-invasive human breast lesions.

The c-erb-B2 protein expression was evaluated by immunohistochemistry in two series of breast lesions. In a retrospective study on a series of 140 breast lesions, among 34 benign lesions, 16 showed an intense or moderate membrane reaction of tumoral cells; of 15 atypical lesions, 6 exhibited a membrane reaction and 34/60 in situ lesions expressed intensely or moderately c-erb-B2 oncoprotein. A prospective investigation was made on a series of 41 lesions from 25 patients, which were selected for their clinico-pathological features. All the samples were positive but the staining intensity was heterogenous. However, it was similar in the various lesions from the same patient. A strong signal was observed in 12 lesions from 7/25 patients, moderate in those of 13 patients and weak in 6 lesions from 5 patients. Taken together, our findings show that a large number of human breast lesions expressed c-erb-B2 oncoprotein, whether benign, atypical or in situ carcinomas. The intensity of the reaction may depend on the patients rather than on the aggressivity of the lesion, except for the infiltrating carcinomas. This suggests that c-erb-B2 oncoprotein in overexpressed at early stages of breast cancer lesions. Although c-erb-B2 oncoprotein is probably not a good marker for prognosis, it may be an indication for a future progression towards or recurrence.

Adult↗
PubMedDate not supplied

Papilloma viruses, warts, carcinoma and Langerhans cells.

In human papillomavirus (HPV) infections, Langerhans cells (LC) are essential in the control of viral infection. The evolution of HPV-derived lesions in the normal population and in graft patients is drastically different, since a high proportion of papillomas progress towards malignancy in transplant recipients. We analyzed the distribution of markers of LC and T lymphocytes, the level of keratinocyte activation and the prevalence of HPV in a series of epithelial lesions obtained from the normal population and from graft patients. The local immune response of warts, condyloma acuminata, Bowen, basal and squamous cell carcinomas (SCC) showed a moderate to intense inflammatory reaction of HLA-DR positive cells, the intensity of the immune reaction being correlated with the degree of malignancy. In the normal population, CD4-positive cells were mainly overexpressed in the dermal infiltrate of condyloma and malignant lesions, whereas in grafted patients such infiltrates were CD4- and CD8-positive without significant predominance of a single T cell subset. The epidermis of most lesions was characterized by a reduced number of CD1a-positive LC with an altered morphology. This was concomitant with the decrease or loss of beta 2-microglobulin by epithelial cells. HLA-DR antigen was sometimes expressed by keratinocytes in genital lesions and SCC from the normal population but has not been detected in immunosuppressed patients. Whereas in the normal population HPV infection was only detected in benign papillomas, both benign and oncogenic HPV DNA may be present in carcinomas from graft patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

Differences in reactivity to cyclosporin A and interferon-gamma of normal and HPV-transformed keratinocytes.

In humans, cyclosporin A (CsA) avoids organ allograft rejection but induces skin carcinomas after long term immunosuppressive treatment; some of these lesions contain human papillomavirus (HPV) DNA. Interferon-gamma (IFN-gamma) is sometimes used in local treatment of persistent or recurrent lesions in normal population. In vivo, both drugs have an effect on keratinocytes which remains unclear. Therefore, their effect was studied on in vitro models of normal or HPV-transformed epithelial cell cultures. After exposure of proliferating cells for 1-3 days to 0.5-16 micrograms/ml CsA and 5-160 U/ml IFN-gamma, no cytotoxicity was observed; cell growth was inhibited; cell morphology was altered with CsA and cytoplasmic vacuoles were seen in some cells. Changes in the cell cycle were mainly obtained after treatment with 8 micrograms/ml CsA or 160 U/ml IFN-gamma, with an accumulation in S-phase especially in HPV-transformed cells. Thus, CsA and IFN-gamma affected, normal and HPV-transformed epithelial cells, differently.

Adjuvants, Immunologic↗