[Cryofibrinogenemia: a single-center study at the University Hospital of Toulouse, France]. / Cryofibrinogénémie : étude monocentrique au CHU de Toulouse.

PURPOSE: Cryofibrinogenemia is an unknown disorder and studies dedicated to it are limited. The aim of our study was to report on the incidence, clinical manifestations and associated diseases in patients with isolated cryofibrinogenemia. METHODS: This is a retrospective single-center study. Patients included in this study had a positive and isolated detection of cryofibrinogen between January 1st, 2011 and December 31st, 2012. Identification was possible through the database of the laboratory of immunology. RESULTS: Two hundred and eighty-one consecutive orders of cryofibrinogenemia were identified. Seventy-three patients had a positive detection of cryofibrinogenemia. Among them, 12 had an isolated cryofibrinogenemia and sixty-one patients (84%) had concomitant cryofibrinogenemia and cryoglobulinemia. The mean age was 59±19years. Seven patients were female (58%). Cutaneous manifestations were present in half case. Peripheral nerve involvement was present in 5 cases (42%) and rheumatic manifestations in 4 patients (33%). A thrombotic event was reported in 7 patients (58%). Renal impairment was present in 7 patients. The median cryofibrinogen concentration was 254±304mg/L. Five patients had a secondary cryofibrinogenemia. The most often prescribed treatment was corticosteroids. CONCLUSION: Cryofibrinogenemia is an unknown disorder. Testing for cryoglobulinemia is more frequent than for cryofibrinogenemia whereas clinical manifestations are similar. Detection of cryofibrinogen is positive in most of the cases, with an important prevalence of thrombotic events in this population. This study confirms the importance of conducting prospective studies on cryofibrinogenemia.

Keeping the memory of smallpox virus.

Smallpox virus eradication was one of the greatest successes of the 20th century. Moreover, the quest to combat its use in biological warfare, has fueled efforts to understand residual immune memory and to develop new animal models by the scientific community. Although the literature is full of animal studies of vaccinia virus infection, continuing efforts have helped to increase our knowledge regarding humoral and cellular memory to non-persistent pathogens and to study factors that might influence further vaccination strategies in humans. In addition, the potent immunostimulatory action of poxvirus vectors has led to development and evaluation of new-generation vaccine candidates, which will be discussed in this review.

[Thymus function and autoimmunity]. / Fonction thymique et auto-immunité.

PURPOSE: Thymus is the site of T-cell development and is essential for the induction of self-tolerance, by deletion of autoreactive T lymphocytes (negative selection) and by generation of regulatory T cells. Defect of the selection mechanism of both types of lymphocytes lead to autoimmune diseases. CURRENT KNOWLEDGE AND KEY POINTS: Elimination of potentially self-reactive T cells in the thymus requires the intrathymic expression of ubiquitous and "tissue-specific" antigens. Some thymic antigen expressions are dependent on AIRE expression. Mutations in the AIRE gene that are associated with the absence of autoantigen expression in the thymus, defects in the peptide presentation or in apoptosis can allow autoreactive T cells to escape negative selection, and are associated with autoimmune diseases. Recent data are now available concerning the thymic selection of autoreactive regulatory T cells. The Foxp3 gene was recently shown to be predominantly expressed in regulatory T cells and could be a more specific marker of regulatory T cells than phenotypic markers. FUTURE PROSPECTS AND PROJECTS: Animal models show that regulatory T cells injection or intrathymic inoculation of antigen lead to immunological tolerance in autoimmunity and transplantation. These novel strategies could be used in human.

Virological exploration of individuals with discordant HIV screening tests.

Screening for HIV infection can use many algorithms. When two different HIV antibody assays are used, discordant results may occur. To discriminate between HIV seroconversion, HIV variant infection and false positive reactivity, 30 consecutive subjects with two discordant HIV antibody-screening assays were extensively investigated for HIV infection. No subject had HIV seroconversion or reached HIV seropositivity criteria after a follow-up of 3 months. By contrast 36% became HIV negative by the use of both HIV screening assays. p24 Antigen, HIV-1 RNA, HIV-1 DNA, HIV-2 DNA assays and HIV isolation by sensitive culture were unable to identify HIV infection in the 30 subjects with discordant HIV screening assays. The data suggest that the use of two HIV screening assays increase false-positive HIV results without increasing clinical sensitivity. To compliment follow-up of HIV screening, early testing for HIV RNA could be useful to identify or eliminate a recent infection.

Mutations of the 3' untranslated region of the SDF1 gene in apes and monkeys: potential impact on sensitivity to AIDS induced by lentiviruses.

The comparison of the stromal cell-derived factor-1 (SDF1) gene 3' untranslated region (3'UTR) of four great ape and four monkey species with their human counterparts shows that the human SDF1-3'A mutation is present in primate species that are the most susceptible to lentivirus-induced AIDS and is absent in species that are particularly resistant to lentivirus-induced AIDS. The results enlighten the possible relationship between SDF1-3'UTR polymorphism and sensitivity to AIDS.

Shift in HIV resistance genotype after treatment interruption and short-term antiviral effect following a new salvage regimen.

OBJECTIVE: To investigate the changes in genotypic drug-resistance pattern, plasma HIV RNA and CD4 cell count after treatment interruption and assess the short-term antiviral effect of a new salvage regimen. DESIGN: Prospective study of 38 patients with multiple failing regimens who had completely stopped all medication for 3 months before a three to five-drug regimen was reintroduced according to clinical guidelines. METHODS: Patients were tested for HIV resistance before and after treatment interruption by population-based sequencing and clonal analysis of selected patients. RESULTS: Discontinuation of therapy for 3 months was associated with a median increase in HIV RNA of 0.4 log10 and a median decrease in CD4 cell count of 43 x 10(6)/l. Sixty-one per cent of patients had a shift from the drug-resistant genotype to a predominantly wild-type genotype. The patients significantly likely to show genotype reversion were those in Centers for Disease Control groups A or B, who had been exposed to few drugs, had a low plasma HIV RNA, or a high CD4 cell count. The only independent factor predicting genotype reversion was the clinical stage. The median change in plasma HIV RNA at month 3 after treatment reintroduction was -2.3 log10 copies/ml in patients who had genotype reversion compared with -0.6 log10 copies/ml in patients without genotype reversion (P = 0.004). CONCLUSION: Suspending treatment for 3 months after multiple failures could be a suitable strategy for optimizing salvage therapy provided it is instituted early, before the HIV disease becomes too advanced.

Chlamydia pneumoniae induces interleukin-10 production that down-regulates major histocompatibility complex class I expression.

Recently, it was demonstrated that CD8(+) T cells are important for the response against Chlamydia pneumoniae. By use of the human monocytic cell line U937 and human monocytes taken from peripheral blood, we investigated the effect of infection on various molecules critical for CD8(+) T cell function. A strong secretion of interleukin (IL)-10 by infected cells was observed, together with an inhibited expression of major histocompatibility complex (MHC) class I antigens, but without significant alteration of tumor growth factor-beta secretion or MHC class II expression. Recombinant IL-10 added to uninfected U937 cells decreased the expression of MHC class I, whereas blocking antibodies to IL-10 and its receptor abolished the C. pneumoniae-induced inhibition of MHC class I expression. Analysis of our data provides evidence that IL-10 secretion induced by C. pneumoniae infection of monocytic cells down-regulates the expression of MHC class I molecules and thereby might reduce the presentation of bacterial epitopes by MHC. This would decrease the ability of CD8(+) T cells to eliminate infected cells.

Prognostic of DNA-synthesizing enzyme activities (thymidine kinase and thymidylate synthase) in 908 T1-T2, N0-N1, M0 breast cancers: a retrospective multicenter study.

Among the methodological approaches of tumor proliferation, thymidine kinase (TK) and thymidylate synthase (TS) assays take into account the specific pathways of pyrimidine synthesis. Studies pointing to a prognostic value of TK and TS in breast cancer involved small numbers of patients. We investigated the prognostic value of these enzymes and their combination in a large retrospective multicenter study. Nine hundred eight T1T2, N0N1, M0 primary breast cancer samples (median follow-up 68 months) were tested. TK and TS were measured in cytosols by using standardized radioenzymatic methods. Although a positive correlation was obtained between TK and TS (p<10(-5)), major discrepancies were observed in some tumors. High levels of both enzymes were associated with large tumor size, histological grade III and steroid receptor-negative tumors. Univariate analysis showed that TK, TS and their combination were predictive of poor metastasis-free (MFS) (p < 10(-4); p=0.004; p < 10(-4)) and disease-free survival (DFS) (p < 10(-4); p=0.007; p=0.0001). TK was selected as an independent factor for MFS in Cox analysis. It was the only variable selected in node-negative patients. Subgroups with specific outcomes, with possible therapeutic implications, were identified: a) in node-negative patients not receiving adjuvant treatment, TK values in the 4th quartile were associated with poor MFS (p=0.0002) and DFS (p=0.0005) as compared to the other quartiles; b) in node-positive patients receiving adjuvant chemotherapy, low levels of both TK and TS were associated with the highest survival rates (MFS: p=0.04; DFS: p=0. 03).

[Standardization and quality control in the evaluation of proliferation parameters in T1T2, N0N1, M0 breast cancer : multicentric retrospective study I. DNA synthesis enzyme activities]. / Standardisation et mise en place d'une assurance qualité dans l'évaluation des paramètres de prolifération de 1,003 cancers du sein T1T2, N0N1, M0: étude multicentrique I. Enzymes de réplication et de transduction du signal.

As part of a clinical research project co-ordinated in Grenoble, six French institutions (CRLCC Angers, CHU Grenoble, Hospices civils Lyon, AP Marseille, CRLCC St-Cloud, CHU Tours) grouped together in order to study the following proliferative parameters in primary breast cancer: DNA synthesis enzymes [thymidine kinase (TK), thymidylate synthase (TS)], signal transduction enzyme [protein tyrosine kinase (PTK)] and S-phase fraction (%S). TK, TS and PTK were measured in cytosols using radio-enzymatic biochemical methods. S-phase was estimated using flow cytometry. The first step consisted in standardization and technical validation of the measurements. The second step consisted in the clinical validation by using a retrospective series of 1,003 breast cancers T1T2, N0N1, M0. We report the results of the first step, together with the distributions of the variables and their relationship with classical clinical variables: 1) Using standardized methods and a cytosolic control, a good reproducibility of measurements was obtained, whether assays were performed in one (TS, PTK) or in several laboratories (TK). 2) Significantly different distributions of TK and TS were observed between the different centres mainly due to different conditions of storage of tumours and cytosols. 3) A highly significant correlation was observed between TK, TS and PTK. Highest TK, TS and PTK levels were observed in tumours with high histological grade or receptor negative tumors. This study clearly illustrates the importance of quality assurance of multicentre studies.

[Neonatal type 1 pneumococcal meningitis and maternal septicemia]. / Méningite néonatale à pneumocoque de type 1 et septicémie maternelle.

The most common organisms in neonatal meningitis are group B streptococcus and Gram negative enteric bacteriae. Although Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae are the most frequent causes of meningitis in infancy and childhood, they are uncommon in newborns. We report one case of neonatal meningitis and maternal septicemia.

Protein tyrosine kinase activity in 350 T1/T2, N0/N1 breast cancer. Preliminary results.

Protein tyrosine kinases (PTKs) are a family of enzymes sharing a highly conserved catalytic domain which phosphorylates substrate proteins on tyrosine residues. PTKs play a major role in the transduction of the mitogenic signal and are involved in the control of cell proliferation, differentiation, and transformation processes. PTKs can be subdivided into two major types: membrane associated PTKs consisting essentially of growth factor receptors (receptor tyrosine kinases or RTKs) and cytosolic PTKs involved in the intracellular transduction of mitogenic and differentiation signals. From January 1988 to January 1992, PTK activity was assayed in cytosolic fractions prepared from 350 T1-T2, N0-N1 M0, breast carcinomas. Enzymatic activity was measured using phosphate transfer from [32P]-ATP to poly-Glu-Tyr as an artificial substrate. According to our previously reported pilot study, we chose a cut-off value of 12 pmol 32P incorporated min-1 mg-1 protein, corresponding to the median value. We found positive PTK levels (> or = 12 pmol/min/mg) to be correlated with a loss of differentiation according to Scarff-Bloom grade (p < 0.001), negative PR (p = 0.03) and ER status (p = 0.04). With a median follow-up of 30 months (0-82), patients with a positive PTK level presented a smaller 3-year disease free survival than in the PTK negative group of patients (p = 0.07). In Cox multivariate analysis including pT, pN, Scarff-Bloom grade, PR and ER, PTK activity does not emerge as a significant prognostic factor.

Lack of prognostic value of epidermal growth factor receptor in a series of 229 T1/T2, N0/N1 breast cancers, with well defined prognostic parameters.

The prognostic value of epidermal growth factor receptor (EGF-R) was prospectively assessed in a series of 229 clinical T1-T2, N0-N1 breast carcinomas diagnosed between May 1987 and October 1989. EGF-R expression was determined by measuring the specific Bmax of 125I EGF to tumor plasma membrane preparations. Tumor with a Bmax > or = 3 fmol/mg of protein were considered positive with regard to EGF-R expression. With a median follow-up of 34 months, the 3-year overall and disease-free survivals are respectively 92% and 88% for EGF-R < or = 3, and 91% and 86% EGF-R > 3 fmol, showing no significant difference, even when comparing axillary lymph node status. We did not succeed in finding an EGF-R cut-off value which might be significant in univariate analysis. Multivariate analysis of our data indicates that pT (p = 0.001), pN (p = 0.04), and Scarff-Bloom grade (p = 0.04) are the only significant predictors of disease-free survival among the parameters investigated in this study.

Protein tyrosine kinase activity as a prognostic parameter in breast cancer, a pilot study.

Protein tyrosine kinase (PTK) activity was assayed in cytosolic extracts from normal breast tissue, benign tumors, and 84 T1-T2, N0-N1 M0, breast carcinomas. Normal breast tissue extracts yielded an average value of 1.9 +/- 1.1 pmol 32P incorporated/min/mg protein, whereas a mean of 12.5 +/- 6.1 was obtained for cancer samples. With a median follow-up of 34 months, in the series of 40 patients classified N-, PTK positive patients presented a significantly smaller 3-year disease free survival than the PTK negative ones. Multivariate analysis shows that PTK activity emerges as a potential prognostic factor in breast cancer (p = 0.02). These preliminary results will be updated on a bigger cohort of patients.

Prognostic value of epidermal growth factor receptor in a series of 303 breast cancers.

125I-EGF (epidermal growth factor) binding assay was used in tumoral specimens concerning 303 clinical T1-T2, N0-N1 breast carcinoma diagnosed between May 1987 and October 1989. Binding assay for epidermal growth factor receptor (EGFR) was performed using single saturating concentration of 125I-EGF incubated with membrane preparations in the presence or absence of unlabelled EGF. A median value of 3 fmol EGF binding capacity per mg of membrane was obtained and then selected as the threshold value to define positive and negative EGFR tumour samples. According to this definition, 50.8% of the samples were EGFR positive. We noted an inverse relationship between the expression of EGFR and that of oestrogen receptor, and a decreased EGFR expression with tumour differentiation. With a rather short median follow-up (16 months), the multivariate analysis shows that progesterone receptor appears as the only powerful predictor of disease-free survival (P = 0.002), taking into account that 70% of the patients received an adjuvant medical treatment.