Seven years (2015-2021) of blood donor screening for HEV-RNA in France: lessons and perspectives

BACKGROUND

The French health authorities are considering expanding the current selective hepatitis E virus (HEV)-RNA testing procedure to include all donations in order to further reduce transfusion-transmitted HEV infection. Data obtained from blood donors (BDs) tested for HEV-RNA between 2015 and 2021 were used to assess the most efficient nucleic acid testing (NAT) strategy.

MATERIALS AND METHODS

Viral loads (VLs) and the plasma volume of blood components, as well as an HEV-RNA dose of 3.85 log IU as the infectious threshold and an assay with a 95% limit of detection (LOD) at 17 IU/mL, were used to assess the proportion of: (i) HEV-RNA-positive BDs that would remain undetected; and (ii) blood components associated with these undetected BDs with an HEV-RNA dose >3.85 log IU, considering 4 NAT options (Individual testing [ID], MP-6, MP-12, and MP-24).

RESULTS

Of the 510,118 BDs collected during the study period, 510 (0.10%) were HEV-RNA-positive. Based on measurable VLs available in 388 cases, 1%, 15.2%, 21.8%, and 32.6% of BDs would theoretically pass undetected due to a VL below the LOD of ID, MP-6, MP-12, and MP-24 testing, respectively. All BDs associated with a potentially infectious blood component would be detected with ID-NAT while 13% of them would be undetected with MP-6, 19.6% with MP-12, and 30.4% with MP-24 depending on the plasma volume. No red blood cell (RBC) components with an HEV-RNA dose >3.85 log IU would enter the blood supply, regardless of the NAT strategy used.

DISCUSSION

A highly sensitive ID-NAT would ensure maximum safety. However, an MP-based strategy can be considered given that: (i) the risk of transmission is closely related to the plasma volume of blood components; (ii) RBC are the most commonly transfused components and have a low plasma content; and (iii) HEV-RNA doses transmitting infection exceed 4 log IU. To minimise the potential risk associated with apheresis platelet components and fresh frozen plasma, less than 12 donations should be pooled using an NAT assay with a LOD of approximately 20 IU/mL.

Risk of a blood donation contaminated with hepatitis E virus entering the blood supply before the implementation of universal RNA screening in France

BACKGROUND AND OBJECTIVES

The risk of a blood donation contaminated with hepatitis E virus (HEV) entering the blood supply before introducing universal HEV-RNA screening in France was estimated to assess the benefit of such a measure.

MATERIALS AND METHODS

The results of selective HEV nucleic acid testing (HEV-NAT) performed in mini pool of six plasma donations between 2018 and 2020 were extrapolated to the whole blood donor (BD) population after adjustment on three variables: regional establishment, sex and age group.

RESULTS

Among the 246,285 plasma donations collected from 172,635 BDs tested for HEV-RNA, 248 (10.1/10,000) were positive. The extrapolation to all BDs led to an estimated rate of 5.9/10,000 donations (95% confidence interval [CI]: 4.5-7.4) which would be positive to HEV-RNA and a prevalence of 9.9/10,000 BDs (95% CI: 7.5-12.3). This prevalence was 4.4 times higher in males than females (16.8/10,000 vs. 3.8/10,000, p < 10^-4 ). The highest prevalence was observed in males in the 30-39 age group (20.5/10,000) and the lowest in females in the 50-70 age group (2.8/10,000).

CONCLUSION

The risk of an HEV-RNA-positive donation entering the blood supply was estimated at 1 in 1682 donations. This risk does not translate directly to the risk of HEV transfusion transmission, which mainly depends on the total number of viral particles in the transfused blood component and the sensitivity of NAT.

[Techniques and complications of non-genetic risk reducing mastectomies: Guidelines of the National College of French Gynecologists and Obstetricians (CNGOF)]

OBJECTIVE

Based on an updated review of the international literature covering the different surgical techniques and complications of risk reducing mastectomies (RRM) in non-genetic context, the Commission of Senology (CS) of the College National des Gynécologues Obstétriciens Français (CNGOF) aimed to establish recommendations on the techniques to be chosen and their implementation.

DESIGN

The CNGOF CS, composed of 24 experts, developed these recommendations. A policy of declaration and monitoring of links of interest was applied throughout the process of making the recommendations. Similarly, the development of these recommendations did not benefit from any funding from a company marketing a health product. The CS adhered to and followed the AGREE II (Advancing guideline development, reporting and evaluation in healthcare) criteria and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) method to assess the quality of the evidence on which the recommendations were based. The potential drawbacks of making recommendations in the presence of poor quality or insufficient evidence were highlighted.

METHODS

The CS considered 6 questions in 4 thematic areas, focusing on oncologic safety, risk of complications, aesthetic satisfaction and psychological impact, and preoperative modalities.

RESULTS

The application of the GRADE method resulted in 7 recommendations, 6 with a high level of evidence (GRADE 1±) and 1 with a low level of evidence (GRADE 2±).

CONCLUSION

There was significant agreement among the CS members on recommendations for preferred surgical techniques and practical implementation.

Low rate of RNAemia in blood donations collected during the first wave of COVID-19 in France

BACKGROUND

To investigate the transmission of SARS-CoV-2 via blood, we conducted retrospective molecular screening in blood donated during the first pandemic peak in the two French regions with the highest community transmission.

METHODS

Archived plasma samples randomly selected from donations collected between 23 and 29 March, 2020, in Eastern and Northern regions of France were tested for SARS-CoV-2 RNA in minipools of 4 donations (MP4) using the Grifols ProcleixSARS-CoV-2 assay. Reactive MP4 and the 4 corresponding plasmas were further tested with alternative RT-PCRs and sequencing. Testing for SARS-CoV-2 antibodies and in-vitro infectivity in cell culture were also performed.

RESULTS

Among the 2,818 MP4 (corresponding to 9,672 donations) tested for viral RNA, 5 were weakly reactive. Among the 20 plasmas included in these 5 MP4, one presented low-level reactivity with RT-PCRs and Procleix SARS-CoV-2 and was confirmed on sequencing. The estimated prevalence was 1.03/10,000 (95% CI 0-3.1). The 20 plasmas were antibody non-reactive and none of them showed cytopathic effects in cell-culture. When recalled, the index-donor declared having had symptoms compatible with SARS-CoV-2 infection a few days after donation. The two immunocompromised recipients transfused with red blood cells and an inactivated pooled platelet product did not develop COVID-19.

CONCLUSION

Our results indicated a low prevalence of SARS-CoV-2 RNA in the plasma of asymptomatic blood donors during the pandemic peak and no evidence of infectivity in vivo and in vitro. The transfusion risk remains theoretical and does not justify the implementation of SARS-CoV-2 NAT for blood donations. This article is protected by copyright. All rights reserved.

The Relationship between Plasma Microparticles, Protein S and Anticardiolipin Antibodies in Patients with Human Immunodeficiency Virus Infection

The high prevalence of free protein S deficiency in human immunodeficiency virus (HlV)-infected patients is poorly understood. We studied 38 HIV seropositive patients. Free protein S antigen values assayed using the polyethylene-glycol precipitation technique (PEG-fS) were statistically lower in patients than in controls. These values using a specific monoclonal antibody-based ELISA (MoAb-fS) and the values of protein S activity (S-act) were not statistically different between patients and controls. C4b-binding protein values were not different from control values. In patients, PEG-fS values were lower than MoAb-fS values. Ten patients had a PEG-fS deficiency, 4 patients had a MoAb-fS deficiency and 8 had a S-act deficiency. Protein S activity and MoAb-fS were lower in clinical groups with poor prognosis and in patients with AIDS but PEG-fS was not. A trend for reduced S-act/MoAb-fS ratios was observed in patients. PEG-fS was negatively correlated with anticardiolipin antibody titers whereas MoAb-fS was not. The plasma of PEG-fS deficient HIV-patients contained high amounts of flow cytometry detectable microparticles which were depleted from plasma by PEG precipitation. The microparticles were partly CD42b and CD4 positive but CD8 negative. These microparticles were labelled by an anti free protein S monoclonal antibody. The observed differences between MoAb-fS and PEG-fS values were correlated with the amount of detectable plasma microparticles, just like the differences between MoAb-fS and S-act. Plasma microparticles correlated with anticardiolipin antibody titers.

In summary, free protein S antigen in HIV infected patients is underestimated when the PEG precipitation technique is used due to the presence of elevated levels of microparticles that bind protein S. The activity of free protein S is also impaired by high levels of microparticles. The prevalence of free protein S deficiency in HIV positive patients is lower than previously published (4/38, -10%) and is correlated with poor prognosis. By implication, use of a PEG precipitation technique might give artefactually low free protein S antigen values in other patient groups if high numbers of microparticles are present. In HIV patients, high titers of anticardiolipin antibodies are associated with high concentrations of cell-derived plasma microparticles.

Prospective Evaluation of the Prevalence of Haemostasis Abnormalities in Unexplained Primary Early Recurrent Miscarriages

The prevalence of haemostasis abnormalities was evaluated in 500 consecutive women with unexplained primary recurrent miscarriages. Two matched reference groups with no antecedent of miscarriage were studied: 100 healthy mothers and 50 childless women.

In the prospective part of the study, we found 9.4% of the patients (95% C.I.: 6.8-12%) with an isolated factor XII deficiency, 7.4% of the patients (5.0-9.8%) with primary antiphopholipid antibodies, 47% of the patients (42.6-51.4%) with an insufficient response to the venous occlusion test and an isolated hypofibri- nolysis was found in 42.6% (38.2-47%) of the patients (reference groups: respectively 0/150, 3/150, 2/150, 2/150, pclO’3). Willebrand disease, fibrinogen deficiency, antithrombin, protein C or protein S deficiencies were not more frequent in recurrent aborters than in members of the reference groups. In the retrospective part of the study, cases of plasma resistance to activated protein C were not abnormally frequent.

Patients had higher Willebrand factor antigen (vWF), tissue-type plasminogen activator antigen (t-PA), plasminogen activator inhibitor activity (PAI) and D-dimers (D-Di) than the reference women. Values of vWF, t-PA, PAI and D-Di were altogether correlated but were not related to C-reactive protein concentrations. Among patients, those with an antiphospholipid syndrome and those with an insufficient response to the venous occlusion test had higher vWF, t-PA, PAI and D-Di values than the patients with none of the haemostasis-related abnormalities.

Thus, factor XII deficiency and hypofibrinolysis (mainly high PAI) are the most frequent haemostasis-related abnormalities found in unexplained primary recurrent aborters. In patients with antiphospholipid antibodies or hypofibrinolysis, there is a non-inflammatory ongoing chronic elevation of markers of endothelial stimulation associated with coagulation activation. This should allow to define subgroups of patients for future therapeutic trials.

[Muir-Torre syndrome associated with Waldenstrom's macroglobulinemia]

BACKGROUND

Muir-Torre syndrome (MTS), a cutaneous variant of Lynch syndrome, consists of hereditary predisposition to cutaneous tumours and gastrointestinal and gynaecological neoplasms, with autosomal dominant transmission. It is associated with mutations in genes coding for proteins in the DNA mismatch repair system.

PATIENTS AND METHODS

Herein, we report a case of a male patient presenting Waldenstrom's macroglobulinemia since the age of 50 and which, after the age of 65 years, developed into sebaceous tumours (5 sebaceous adenomas, 1 sebaceoma, 1 sebaceous carcinoma) and colonic lesions (4 adenomas). The clinical phenotype was consistent with MTS. Somatic analysis carried out on one sebaceous tumour showed instability of the microsatellites with loss of expression of MSH2 and MSH6 although constitutional genetic analysis showed no germline mutations known to be harmful.

DISCUSSION

This noteworthy case raises a number of questions, including the possibility of association between STM and Waldenstrom's macroglobulinemia, which is discussed herein.

Lifestyle, weight history, nutrition and breast cancer among non-gene carriers: a case-control study

Abstract #6084

We conducted a nested case-control study of 280 French-Canadian women with breast cancer who were non-gene carriers (BRCA) and 280 women without cancer who were also non-gene carriers. A validated lifestyle questionnaire and a food frequency questionnaire were administered to obtain relevant information. It was found that age at the time the subjects reached maximum body mass index (BMI) was significantly associated with breast cancer risk [OR=2.83; 95% CI: (2.34-2.81)]. In addition, a significant association was noted between maximum weight gain at age 20 years [OR=1.68; 95% CI: (1.10-2.58)], 30 years [OR=1.96; 95% CI: (1.46-3.06)], and 40 years [OR=2.50; 95% CI: (1.72-3.97)] and breast cancer risk. Women who smoked more than 9 pack-years of cigarettes had a higher risk of breast cancer [OR=1.59; 95% CI: (1.57-2.87)]. Subjects who engaged in moderate physical activity had a 52% decreased risk of breast cancer [OR=0.48; 95% CI: (0.31-0.74)], but this was not evident for vigorous physical activity. It was observed that total energy intake was significantly associated with breast cancer risk [OR=2.54; 95% CI: (1.67-3.84)]. Women who drank more than 8 cups of coffee per day had 40% more chance of developing breast cancer [OR=1.40 (95% CI: (1.09-2.24)]. Subjects who consumed more than 9 grams of alcohol (ethanol) per day had the highest risk of breast cancer [OR=1.55 (95% CI: (1.02-2.37)]. None of the other nutrients and dietary components was significantly associated with non-gene carrier breast cancer risk. This study suggests that BMI, maximum weight gain during the second, third and fourth decades, smoking, total energy intake, and high intake of both alcohol and coffee may increase the risk of breast cancer among non-gene carrier French-Canadian women, while moderate physical activities may reduce the risk.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6084.

Risk model for severe anemia requiring red blood cell transfusion after cytotoxic conventional chemotherapy regimens. The Elypse 1 Study Group

PURPOSE

Cancer patients frequently experience anemia as a consequence of myelosuppressive therapy or bone marrow invasion.

PATIENTS AND METHODS

A risk model for chemotherapy-induced severe anemia requiring RBC transfusions (SARRT) within 31 days after the administration of chemotherapy was delineated in the cohort of cancer patients treated with chemotherapy in the Department of Medicine of Centre Léon Bérard in 1996 (CLB-1996). The risk model was tested on a series of 797 patients treated in 1997 (CLB-1997) and on 295 patients included in a multicenter prospective series (ELYPSE 1).

RESULTS

One hundred seven of the 1,051 patients of the CLB-1996 cohort (10%) experienced SARRT. In univariate analysis, only female sex, performance status greater than 1, hemoglobin level less than 12 g/dL before chemotherapy on day 1 (d1), and d1 lymphocyte count < or = 700/microL significantly correlated with the risk of SARRT. Using logistic regression, d1 hemoglobin level less than 12 g/dL (odds ratio [OR] = 14.0; 95% confidence interval [CI], 7 to 30), performance status greater than 1 (OR = 2.2; 95% CI, 1.4 to 3.5), and d1 lymphocyte count < or = 700/microL (OR = 1.7; 95% CI, 1. 1 to 2.6) were identified as independent risk factors for SARRT. These three factors were given arbitrary risk coefficients of 3, 1, and 1 respectively, and a risk score for each individual patient was obtained by adding the coefficients. The calculated probability of RBC transfusions was 30% for patients with a score > or = 4, and 11%, 4%, and 1% in patients with a score of 2 or 3, 1, and 0 respectively. This model was then tested and validated in the CLB-1997 and ELYPSE 1 series.

CONCLUSION

This risk index could be useful to identify patients at high risk for chemotherapy-induced SARRT who might be appropriate candidates for prophylactic erythropoietin treatment.

Prevalence of germline mutations of hMLH1, hMSH2, hPMS1, hPMS2, and hMSH6 genes in 75 French kindreds with nonpolyposis colorectal cancer

Hereditary nonpolyposis colorectal cancer (HNPCC) is a syndrome characterized by familial predisposition to colorectal carcinoma and extracolonic cancers of the gastrointestinal, urological, and female reproductive tracts. This dominant disorder is caused by germline defects in one of at least five DNA mismatch repair (MMR) genes: hMLH1, hMSH2, hPMS1, hPMS2, and hMSH6 (GTBP). Germline mutations of hMSH2 and hMLH1 are also frequently identified in families not fulfilling all the Amsterdam criteria, thereby demonstrating that the involvement of these genes is not confined to typical HNPCC. To evaluate the respective involvement of the various MMR genes in typical and incomplete HNPCC syndromes, we have performed an analysis of the hMLH1, hMSH2, hPMS1, hPMS2, and hMSH6 genes in a large series of French kindreds (n=75) with colorectal tumors and/or aggregation of extracolonic cancers belonging to the HNPCC spectrum. Mutational analysis has been performed in all families, without preselection for the tumor phenotype. We have detected 26 pathogenic germline mutations of the hMLH1 and hMSH2 genes and several novel variants of the hPMS1, hPMS2, and hMSH6 genes. Our data confirm that, regardless of the type of families and the tumor phenotype, hPMS1, hPMS2, and hMSH6 germline mutations are rare in familial aggregation of colorectal cancers. Furthermore, they suggest that the presence of multiple primary malignancies in a single individual and the observation of extracolonic tumors in relatives of a colorectal cancer patient should be included among the guidelines for referring patients for genetic testing.

Phase I-II trial of intensification of the MAID regimen with support of lenograstim (rHuG-CSF) in patients with advanced soft-tissue sarcoma (STS)

This study was conducted to determine the maximum tolerated dose of an intensified MAID (mesna, adriamycin, ifosfamide, dacarbazine) regimen with the support of lenograstim in patients with advanced soft tissue sarcomas. Following 1 cycle of MAID at the standard dose, four patients were to be treated at each of five dosage levels: +25%, +45%, +65%, +85%, +100%. Sixteen patients were treated. Because there were no significant differences in hematologic toxicity between patients receiving lenograstim 5 or 10 microg/kg/day (levels 1-5 and 1-10), the data were pooled for comparison with level 2. The median duration of absolute neutrophil count < 0.5 x 10(9)/l was 3 days at level 1 and 7 days at level 2 (p < 0.01). The median platelet nadir was 25 x 10(9)/l at level 1 and 10 x 10(9)/l at level 2 (p < 0.01). The median duration of toxicity-related hospitalization was 3.5 days and 11 days at levels 1 and 2, respectively, (p < 0.001). Mucositis > or = grade III occurred after 3/29 cycles at level 1 and 10/15 cycles at level 2 (p < 0.001). After 4 cycles at level 1, 8/8 patients still had performance status scores < or = 2, and only 4/8 had performance status scores < or = 2 after the second cycle at level 2. Lenograstim enabled an increase of 25% of the MAID regimen. At higher dose levels, severe mucositis and deterioration in performance status were dose limiting.

Marker segregation information in breast/ovarian cancer genetic counseling: is it still useful? Groupe Génétique et Cancer de la Fédération Nationale des Centres de Lutte Contre le Cancer

The use of mutation screening of BRCA1 and BRCA2 genes as a genetic test is still to a certain extent limited and the oncogeneticist may want to use complementary approaches to identify at-risk individuals. In a series of 23 families with at least three breast or ovarian cancer cases, screened for mutations at BRCA1 and BRCA2 and typed for markers at both loci, we investigated the usefulness of marker segregation information at two levels: 1) to what extent can the indirect approach identify the mutation carrier status of screened cases and their first-degree relatives, and 2) in what way does it help to identify the gene implicated in a family in which neither BRCA1 nor BRCA2 mutation has been detected? Using the indirect approach, the carrier status of the screened case could be determined with quasi certainty in three families and with a high probability in eight families. This status could be inferred in unaffected first-degree relatives as almost certain in one family and as highly probable in six families. Fourteen mutations were found concurrently in our series. Among the nine mutation-negative families, we were able to conclude that a BRCA1 mutation most probably segregated in one and that a mutation other than BRCA1 and BRCA2 was probably involved in two families. Our results show that, in small families, little help is to be expected from linkage data and mutation screening is the only way of identifying the origin of a genetic predisposition in a family. Marker segregation information may be useful in some large breast/ovarian cancer families in which no BRCA1 or BRCA2 mutation has been detected.

Cancer genetic clinics: why do women who already have cancer attend?

Cancer patients attend oncogenetic clinics so that the existence of a genetic risk can be checked and the relatives informed. The aim of this study was to describe the expectations of cancer patients about genetic counselling and their beliefs about the aetiology of their disease. A survey based on self-administered questionnaires before and after the consultation was carried out on 115 women with breast/ovarian cancer who attended one of the six French participating clinics. In 59 cases (51%), the consultees' expectations focused on the preventive options available and in 86 cases (75%) on their offspring; 87 (76%) found the consultation informative. On average, the women rated heredity and diet as lower risk factors (P < 0.05) after the consultation than before. Heredity, stress and the environment were thought to be more decisive than diet, smoking and alcohol. 34 patients who seemed unlikely to have a genetic risk in the consultant's opinion thought heredity to be less relevant (P < 0.05) after the consultation than before. At the time of the survey, cancer patients accounted for at least half of the consultees attending oncogenetic clinics in France. They need to have the clinical specificities of their disease and its medical management explained. They attend mainly for their offspring's sake, whereas healthy clients attend for their own sake.

A risk model for thrombocytopenia requiring platelet transfusion after cytotoxic chemotherapy

Severe thrombocytopenia is a rare but life-threatening side effect of cytotoxic chemotherapy for which risk factors are not well known. Our objective was to delineate a risk model for chemotherapy-induced thrombocytopenia requiring platelet transfusions in cancer patients. Univariate and multivariate analysis of risk factors for chemotherapy-induced thrombocytopenia requiring platelet transfusions were performed on the cohort of the 1,051 patients (CLB 1996) treated with chemotherapy in the Department of Medicine of the Centre Léon Bérard (CLB) in 1996. In univariate analysis, performance status (PS) greater than 1, platelet count less than 150, 000/microL at day 1 (d1) before the initiation of chemotherapy, d1 lymphocyte count < or = 700/microL, d1 polymorphonuclear leukocyte count less than 1,500/microL, and the type of chemotherapy (high risk v others) were significantly associated (P < .01) with an increased risk of severe thrombocytopenia requiring platelet transfusions. Using logistic regression, d1 platelet count less than 150,000/microL (odds ratio [OR], 4.3; 95% confidence interval [CI], 1.9 to 9.6), d1 lymphocyte counts < or = 700/microL (OR, 3.37; 95% CI, 1.77 to 6.4), the type of chemotherapy (OR, 3.38; 95% CI, 1.77 to 6.4), and PS greater than 1 (OR, 2.23; 95% CI, 1.22 to 4.1) were identified as independent risk factors for platelet transfusions. The observed incidences of platelet transfusions were 45%, 13%, 7%, and 1.5% for patients with > or = 3, 2, 1, or 0 risk factors, respectively. This model was then tested in 3 groups of patients treated with chemotherapy used as validation samples: (1) the series of 340 patients treated in the CLB in the first 6 months of 1997, (2) the prospective multicentric cohort of 321 patients of the ELYPSE 1 study, and (3) the series of 149 patients with non-Hodgkin's lymphoma treated in the CLB within prospective phase III trials (1987 to 1995). In these 3 groups, the observed incidences of platelet transfusions in the above-defined risk groups did not differ significantly (P > .1) from those calculated in the model. This risk index could be useful to identify patients at high risk for chemotherapy-induced thrombocytopenia requiring platelet transfusions.

Time elapsing from cancer diagnosis and anxiety in women attending cancer genetic clinics

The aim of this study was to investigate the effects of cancer genetic consultations on feelings of anxiety in women with breast/ovarian cancer. Among the 138 women attending six French clinics during a one-year period, 115 (83.3%) answered pre- and post-consultation questionnaires. The state anxiety score (Spielberger's STAI) was lower (paired t-test, p<0.001) after the consultation (34.7 9.4) than before (38.8 10.5). The time elapsing since cancer diagnosis (r=-0.28, p=0.007) was the main predictor of the decrease in anxiety. The patients consulting earlier after their cancer was diagnosed were more anxious before the consultation than those consulting later: whereas their anxiety states after the consultation were similar. The consultation effectively decreased the anxiety observed and the anxiety felt by cancer patients before the consultation may constitute an anticipatory stress response that should be investigated.

Pathology of sporadic breast tumors with LOH at the BRCA1 locus: correlation with histopathological features specific to familial BRCA1 tumors and absence of microsatellite instability

To investigate the coordinated occurrence of loss of heterozygosity (LOH) at the BRCA1 locus and microsatellite instability (MI) in sporadic breast carcinomas, 56 tumors were analysed for both genetic alterations. The comparison of clinicopathological features with the obtained data revealed that LOH at the BRCA1 locus was significantly correlated with features specific for familial BRCA1 tumors and with absence of hormone receptors. No correlation was found between LOH and MI. These results suggest that sporadic and familial breast tumors, where BRCA1 is altered, could display similar clinicopathological features and that LOH and MI are distinct genetic events in sporadic breast carcinogenesis.

Recurrent PIG-A mutation (IVS5+1G-->A) in a paediatric case of paroxysmal nocturnal haemoglobinuria: detection by the protein truncation test

Paroxysmal nocturnal haemoglobinuria (PNH) is an acquired haemopoietic stem cell disorder caused by the absence of glycosyl phosphatidylinositol (GPI)-anchored surface proteins due to a deficient biosynthesis of GPI-anchor. The disease occurs predominantly in adults, and very few cases have been described in children and adolescents. Recent analyses have shown that null mutations in the X-linked PIG-A (phosphatidylinositol glycan-class A) gene are responsible for GPI-anchor deficiency in most PNH adult patients analysed. We report a young male from southern France who was diagnosed with PNH at 12 years of age during follow-up of aplastic anaemia. To further elucidate the molecular basis of PNH occurring in childhood, we used the powerful and rapid protein truncation test to scan for truncative mutations in the entire PIG-A mRNA reverse transcribed and amplified from blood mononuclear cells. The somatic defect responsible for PNH in the patient was found to be a splicing mutation. IVS5+1G-->A, which has previously been described in two Asiatic adults with PNH.

French multicentric evaluation of mdr1 gene expression by RT-PCR in leukemia and solid tumours. Standardization of RT-PCR and preliminary comparisons between RT-PCR and immunohistochemistry in solid tumours. French Network of the Drug Resistance Intergroup, and Drug Resistance Network of Assistance Publique-Hôpitaux de Paris

Since there is no consensus on the techniques for multidrug resistance (MDR) phenotype evaluation, many discrepancies concerning the importance and frequency of mdr1 gene expression in leukemias and solid tumors are observed in the literature. In order to establish an inter-laboratory consensus in France, a multicenter study was carried out to propose further guidelines for MDR phenotype evaluation. The techniques used by the 38 laboratories participating in the trial were: immunodetection (immunohisto and/or cytochemistry, flow cytometry), functional tests, reverse transcription-polymerase chain reaction (RT-PCR) or Northern blot. We present the results obtained by 19 laboratories concerning the measurement of mdr1 gene expression assessed by RT-PCR or Northern blot in: (1)19 samples of tumor cells obtained from leukemic patients; (2) six solid tumor samples obtained at surgery; (3) eight cell lines exhibiting variable levels of resistance, and; (4)10 preparations of RNA and of cDNA obtained from solid tumors. Standardization of the RT-PCR technique and preliminary results comparing RT-PCR with immunohistochemistry in solid tumors are also reported.

Respective evaluation of the prevalence of haemostasis abnormalities in unexplained primary early recurrent miscarriages. The Nimes Obstetricians and Haematologists (NOHA) Study

The prevalence of haemostasis abnormalities was evaluated in 500 consecutive women with unexplained primary recurrent miscarriages. Two matched reference groups with no antecedent of miscarriage were studied: 100 healthy mothers and 50 childless women. In the prospective part of the study, we found 9.4% of the patients (95% C.I.: 6.8-12%) with an isolated factor XII deficiency, 7.4% of the patients (5.0-9.8%) with primary antiphopholipid antibodies, 47% of the patients (42.6-51.4%) with an insufficient response to the venous occlusion test and an isolated hypofibrinolysis was found in 42.6% (38.2-47%) of the patients (reference groups: respectively 0/150, 3/150, 2/150, p < 10(-3)). Willebrand disease, fibrinogen, deficiency, antithrombin, protein C or protein S deficiencies were not more frequent in recurrent aborters than in members of the reference groups. In the retrospective part of the study, cases of plasma resistance to activated protein C were not abnormally frequent. Patients had higher Willebrand factor antigen (vWF), tissue-type plasminogen activator antigen (t-PA), plasminogen activator inhibitor activity (PAI) and D-dimers (D-Di) than the reference women. Values of vWF, t-PA, PAI and D-Di were altogether correlated but were not related to C-reactive protein concentrations. Among patients, those with an antiphospholipid syndrome and those with an insufficient response to the venous occlusion test had higher vWF, t-PA, PAI and D-Di values than the patients with none of the haemostasis-related abnormalities. Thus, factor XII deficiency and hypofibrinolysis (mainly high PAI) are the most frequent haemostasis-related abnormalities found in unexplained primary recurrent aborters. In patients with antiphospholipid antibodies or hypofibrinolysis, there is a non-inflammatory ongoing chronic elevation of markers of endothelial stimulation associated with coagulation activation. This should allow to define subgroups of patients for future therapeutic trials.

Loss of heterozygosity at 7q31 in breast cancer: results from an International Collaborative Study Group. The Breast Cancer Somatic Genetics Consortium

Loss of heterozygosity (LOH) at 7q31 has been claimed to occur in over 80% of all breast cancers and to be of prognostic significance. This would make this genetic alteration the most common event observed in breast cancer to date. Others, however, have been unable to confirm this high incidence. In this multicenter study, we have complied LOH scorings for three polymorphic markers for 7q31-q32 in 683 breast tumors. Although some significant differences between centers existed, no center reported more than 40% LOH, and the average rate was 19%. Disease-free and overall survival of the patients whose tumors carried LOH at 7q31 did not differ significantly from those patients whose tumors showed retention of heterozygosity at 7q31. In a double-blind scoring of a subset of the raw data, an average discordant rate of LOH scoring of 12% was observed. While startling in itself, this was unable to explain the variation among centers, nor the difference with the initially reported high rate of LOH. We conclude that LOH at 7q31 is not important as a genetic alteration in breast cancer as originally suggested, nor a strong determinant of disease outcome.

The relationship between plasma microparticles, protein S and anticardiolipin antibodies in patients with human immunodeficiency virus infection

The high prevalence of free protein S deficiency in human immunodeficiency virus (HIV)-infected patients is poorly understood. We studied 38 HIV seropositive patients. Free protein S antigen values assayed using the polyethylene-glycol precipitation technique (PEG-fS) were statistically lower in patients than in controls. These values using a specific monoclonal antibody-based ELISA (MoAb-fS) and the values of protein S activity (S-act) were not statistically different between patients and controls. C4b-binding protein values were not different from control values. In patients, PEG-fS values were lower than MoAb-fS values. Ten patients had a PEG-fS deficiency, 4 patients had a MoAb-fS deficiency and 8 had a S-act deficiency. Protein S activity and MoAb-fS were lower in clinical groups with poor prognosis and in patients with AIDS but PEG-fS was not. A trend for reduced S-act/MoAb-fS ratios was observed in patients. PEG-fS was negatively correlated with anticardiolipin antibody titers whereas MoAb-fS was not. The plasma of PEG-fS deficient HIV-patients contained high amounts of flow cytometry detectable microparticles which were depleted from plasma by PEG precipitation. The microparticles were partly CD42b and CD4 positive but CD8 negative. These micro-particles were labelled by an anti free protein S monoclonal antibody. The observed differences between MoAb-fS and PEG-fS values were correlated with the amount of detectable plasma microparticles, just like the differences between MoAb-fS and S-act. Plasma microparticles correlated with anticardiolipin antibody titers. In summary, free protein S antigen in HIV infected patients is underestimated when the PEG precipitation technique is used due to the presence of elevated levels of microparticles that bind protein S. The activity of free protein S is also impaired by high levels of microparticles. The prevalence of free protein S deficiency in HIV positive patients is lower than previously published (4/38, approximately 10%) and is correlated with poor prognosis. By implication, use of a PEG precipitation technique might give artefactually low free protein S antigen values in other patient groups if high numbers of microparticles are present. In HIV patients, high titers of anticardiolipin antibodies are associated with high concentrations of cell-derived plasma microparticles.

Study of the organization of the genomes of Escherichia coli, Brucella melitensis and Agrobacterium tumefaciens by insertion of a unique restriction site

Tn5Map, a Tn5 derivative containing the 18 bp I-SceI site, was delivered from a RP4-mobilizable, RK6-derived suicide vector to Escherichia coli HB101, Brucella melitensis and Agrobacterium tumefaciens C58, which all lack natural I-SceI sites in their genomes. Digestion of the DNA from Tn5Map-containing strains and analysis by pulsed-field gel electrophoresis (PFGE) revealed that these derivatives contained a single transposon insertion. These digests also gave direct and independent proof for the single circular chromosome of E. coli, and for the presence of two circular chromosomes in B. melitensis and of a circular and a linear chromosome in A. tumefaciens C58 (which also contains two large circular plasmids). This rapid and versatile technique is potentially applicable to the study of the genomic organization in all Gram-negative bacteria which support Tn5 transposition. Moreover, linearization of circular replicons could be the first step for a rapid method of physical mapping.