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Didier Riethmuller

Publications and source records attributed to Didier Riethmuller.

5 recordsLinked to original sources

Immunohistochemical analysis of CD4+ and CD8+ T-cell subsets in high risk human papillomavirus-associated pre-malignant and malignant lesions of the uterine cervix.

OBJECTIVES: Humoral and cellular immune responses are likely to play a key role for the clearance or persistence and progression of high risk (HR) HPV-associated cervical lesions. Although there are many studies describing the systemic T-cell responses to HPV16 and 18 proteins, few data are available regarding the cellular mucosal immune responses. We used immunohistochemistry to characterize populations of T-immune cells (CD4+, CD8+, CD45RO+) in HR-HPV-infected precancerous and cancerous lesions of the uterine cervix. METHODS: Four biopsies from normal cervix, 9 CIN1 which have regressed (rCIN), 5 CIN1 which have progressed (pCIN) to high grade lesions, 13 CIN3 and 11 invasive carcinomas were included. All dysplasias and carcinomas were HR-HPV-positive and low-risk-HPV-negative. They were stained with monoclonal antibodies specific for CD4, CD8 and CD45RO and examined by microscopy. STATISTICAL ANALYSIS: The Kruskal-Wallis test and the Siegel's and Castelan's method were used. RESULTS.: CD4+ cells predominated in regressing CIN1 both within the stroma and the epithelium with the highest CD4+/CD8+ ratio compared with pCIN1, CIN3 and invasive carcinoma. At the exception of CD45RO+ cells, T cells were detected with similar frequencies in both pCIN1 and CIN3. However, in 7 out of 10 CIN3, CD4+ and CD8+ cells were visible as organized lymphoid follicle structure. The CD8+ and CD45RO+ cells far exceeded the CD4+ cells in invasive cancers. CONCLUSIONS: Density and distribution of immune T cells depend on the malignant potential of HR-HPV lesions. These results suggest that the studied lymphocyte subsets have an important role to fulfil during the natural history of HR-HPV-associated lesions.

CD4-Positive T-Lymphocytes↗

Persistence and load of high-risk HPV are predictors for development of high-grade cervical lesions: a longitudinal French cohort study.

Oncogenic HPV types are the major cause of worldwide cervical cancer, but only a small proportion of infected women will develop high-grade cervical intraepithelial neoplasia or cancer (CIN2/3+). We performed a prospective study including 781 women with normal, atypical squamous cells of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesion (LGSIL) cytology, and infected or not by high-risk (HR) HPV tested by Hybrid Capture II. Women were followed up every 6 months for a median period of 22 months. Among the HR-HPV-positive women at entry, more than half cleared their virus in 7.5 months; the clearance rate was greater for low viral loads than for high loads and also was higher in women with an initial ASCUS/LGSIL smear than in women with normal cytology. The incidence of cytologic abnormalities strongly depended on baseline viral load and HR-HPV persistence. Maintenance of cytologic abnormalities was associated with the outcome of HR-HPV status (negative or =100 pg/mL). Conversely, women who were consistently HR-HPV negative or transiently HR-HPV positive, whatever the cytology at baseline was, did not develop CIN2/3+ during follow-up. Age seemed to affect only the rate of incident HR-HPV infection. In conclusion, our data suggest that women repeatedly tested positive for HR-HPV are at risk of developing CIN2/3+, even when initial cytology is normal. A high viral load could be used as a short-term marker of progression toward precancerous lesions, although lower load does not inevitably exclude progressive disease.

Adolescent↗

New sensitive method for the measurement of lysozyme and lactoferrin for the assessment of innate mucosal immunity. part I: time-resolved immunofluorometric assay in serum and mucosal secretions.

Mucous peristalsis, mucus and immunity proteins, such as lysozyme and lactoferrin, are part of humoral innate immunity. The aim of this study was to develop a quantitative method, a time-resolved-immunofluorometric assay, to measure lysozyme and lactoferrin in sera, saliva, stools and cervico-vaginal secretions. This method was validated in 51 healthy subjects. Linearity for lysozyme was between 1.02 and 25 microg/l and for lactoferrin between 1.02 and 100 microg/l. The detection limit was 0.5 microg/l for lysozyme and 1 microg/l for lactoferrin. Albumin and alpha1-antitrypsin were measured by immuno-nephelometry to calculate salivary, intestinal and cervico-vaginal coefficients of excretion. Lysozyme and lactoferrin were present in all types of mucosal surfaces. Very high concentrations of lysozyme and lactoferrin were found in cervico-vaginal fluid (166.2 and 72.7 mg/l, respectively), compared to the concentrations found in the other mucosal fluids. Lysozyme in stools was produced at the rate of 0.42 mg/d compared to 0.02 mg/d lactoferrin production. Lysozyme and lactoferrin greatly exceeded the values expected from the molecular weight-affected seepage from plasma, suggesting primarily local synthesis in healthy subjects. Quantitative measurement of lysozyme and lactoferrin can aid in the assessment of the activity of mucus-associated lymphoid tissues in innate immunity, and can help in further understanding of the role of these proteins in mucosal diseases.

Adolescent↗

TP53 polymorphism at exon 4 in caucasian women from eastern France: lack of correlation with HPV status and grade of cervical precancerous lesions.

OBJECTIVE: To investigate the codon 72 TP53 polymorphism in women from eastern France with normal or abnormal cervical cytology. STUDY DESIGN: We analyzed the TP53 allele distribution by denaturant gradient gel electrophoresis assay and the human papillomaviruses (HPV) infection in 138 cervical smears: 50 normal, 20 atypical squamous cells of undetermined significance, 40 low grade squamous intraepithelial lesions, 28 high grade squamous intraepithelial lesions. RESULTS: The viral DNA prevalence increased with cytological abnormalities. The rates of arginine (Arg) and proline (Pro) homozygosity and Arg/Pro heterozygosity were 49, 0.72, and 51%, respectively. No association was found between HPV status and TP53 polymorphism. No differences were observed in the frequency of the TP53 genotypes according to cytology. CONCLUSION: The TP53 Arg/Arg genotype does not appear to represent a risk factor in the progression of HPV associated cervical lesions. We were not able to confirm that the TP53 genotype increases the susceptibility to be infected by HPV or to develop HGSIL, and a fortiori invasive carcinoma of the cervix.

Adolescent↗