Proteomics applied to transfusion plasma: the beginning of the story.

'Safe blood' is and has always been the major concern in transfusion medicine. Plasma can undergo virus inactivation treatments based on physicochemical, photochemical or thermal methodologies for pathogen inactivation. The validation of these treatments is essentially based on clottability assays and clotting factors' titration; however, their impact on plasma proteins at the molecular level has not yet been evaluated. Proteomics appears as particularly adapted to identify, to localize and, consequently, to correlate these modifications to the biological activity change. At the crossroads of biology and analytical sciences, proteomics is the large-scale study of proteins in tissues, physiological fluids or cells at a given moment and in a precise environment. The proteomic strategy is based on a set of methodologies involving separative techniques like mono- and bidimensional gel electrophoresis and chromatography, analytical techniques, especially mass spectrometry, and bioinformatics. Even if plasma has been extensively studied since the very beginning of proteomics, its application to transfusion medicine has just begun. In the first part of this review, we present the principles of proteomics analysis. Then, we propose a state of the art of proteomics applied to plasma analysis. Finally, the use of proteomics for the evaluation of the impact of storage conditions and pathogen inactivation treatments applied to transfusion plasma and for the evaluation of therapeutic protein fractionated is discussed.

[Safety of blood products and B19 parvovirus]. / Sécurité des produits sanguins labiles et parvovirus B19.

More than 25 years after the discovery of the parvovirus B19 (B19), the issue of the safety of blood components and the screening of this virus in blood donations is still debated. Although more often transmitted by respiratory route, B19 may also be transmitted by transfusion of blood components. This risk of exposure has been estimated to a frequency ranging from 1/625 to 1/50,000, according to the sensitivity of the detection methods and to seasonal epidemiologic circumstances. Usually, B19 is responsible for benign pathologies. However, such an infection can have a serious clinical outcome in three categories of susceptible recipients: (i) patients with shortened red cell survival (thalassemia major, sickle cell disease, other hemolytic diseases); (ii) immunocompromised patients (previously exposed to B19 or not) (iii) and pregnant women (not previously exposed the B19), with a risk of hydrops fetalis or of intrauterine death. Selected blood components, not collected during the short but highly viremic pre-seroconversion phase, could be reserved for these three groups of at-risk recipients. The screening of such viremic donations could be performed with nucleic acid testing (NAT), but an alternate strategy could be the selection of B19 immunised donors far from the primo-infection (positive for B19 IgG and negative for B19 IgM, or only positive for IgG at two controls distant of several months). However, the existence of persistently B19-infected individuals carrying B19 DNA despite the presence of specific IgG (estimated at 1% of blood donors) could constitute a potential threat for transfused immunocompromised recipients. The screening of such donors, which could be performed through a very highly sensitive NAT, would be justified only if the infectivity of such blood donations is demonstrated. If not, a screening of blood donors positive for B19 IgG would be a sufficient preventive measure.

HCV RNA in blood donors with isolated reactivities by third-generation RIBA.

BACKGROUND: The objective of this collaborative study was to learn the proportion of HCV RNA-positive samples obtained from a population of donors with isolated anti-HCV reactivities by third-generation RIBA (RIBA-3) (indeterminate results). STUDY DESIGN AND METHODS: During a 2-year period, 11 blood transfusion centers kept all samples with indeterminate RIBA-3 results to test them by PCR, using both local and commercial techniques. RESULTS: Of the 758 RIBA-3 indeterminate samples, 10 (1.3%) were positive for HCV RNA: 3. 3 percent (6/180) and 1.3 percent (4/317) of samples with anti-core or anti-NS3 reactivity, respectively, and none of the 52 and 209 samples with anti-NS4 or anti-NS5 reactivity, respectively. HCV RNA-positive donors with anti-core reactivity were infected with different subtypes (1 with HCV subtype 1b, 1 with 2, 1 with 2a/2c, 2 with 3a, and 1 with 5a), and a follow-up indicated a chronic-carrier state in two of the six donors. Acute hepatitis was diagnosed in three of the four donors with anti-NS3 reactivity alone. Two of these three were IV drug users and were infected with subtype 1a. CONCLUSION: HCV RNA-positive donors with indeterminate results in RIBA-3 are extremely rare, but they do exist. They were observed only when either anti-core or anti-NS3 was present. With such a RIBA-3 profile, PCR testing remains necessary to reveal an eventual acute or chronic HCV infection.

Large-scale screening for human parvovirus B19 DNA by PCR: application to the quality control of plasma for fractionation.

BACKGROUND AND OBJECTIVES: Because human parvovirus B19 (B19) has been transmitted by various plasma-derived medicinal products, the 'Laboratoire français du Fractionnement et des Biotechnologies' (LFB) implemented PCR screening of plasma pool samples for B19 DNA as part of the quality control of plasma source material. MATERIALS AND METHODS: Plasma pool samples (average of 46.5 donations) were tested for B19 DNA by PCR and by immunological detection of PCR products. The viral DNA content was determined by means of a TaqMantrade mark-based, quantitative PCR. RESULTS: From plasma corresponding to 2-year collections in France, and representing 4.26 million donations from approximately 1.25 million voluntary unpaid donors, the average frequency of positive donations was 1/5,950 and reached 1/1,420 during an epidemic. Levels of B19 DNA in positive pools ranged from <10(2) to 10(11) copies/ml. CONCLUSION: A large-scale PCR plasma screening increased the safety of LFB's wide range of products with respect to B19, a virus particularly resistant to physicochemical inactivation procedures.

Lessons from a multicentre study of the detectability of viral genomes based on a two-round quality control of GB virus C (GBV-C)/hepatitis G virus (HGV) polymerase chain reaction assay.

The aim of this study was to determine whether multicentre quality controls for the detectability of viral genomes could contribute to the improvement of diagnostic performance in the participating laboratories. The study was carried out during two successive rounds, during which 18 laboratories specialized in nucleic acid testing analyzed, through a polymerase chain reaction (PCR) assay, a common panel of GB virus C (GBV-C)/hepatitis G virus (HGV) RNA-positive and -negative samples. During the first round, the laboratories used either an 'in-house' PCR procedure or a partly standardized commercial test. After decoding the results of the first round, the procedures of the participating laboratories were compared in order to establish a consensus procedure deduced from those of the laboratories which provided the best results. During the second round, each participating laboratory could use the resulting consensus procedure, or its own procedure, or both. The results of this quality control study indicated that, whatever method used, even specialized and trained laboratories may give false-negative or false-positive results. The commercial assay did not guarantee a systematic high quality level of results. The striking heterogeneity of results observed among laboratories using the same commercial assay confirm that molecular biology methods need skilled technicians. The results of this quality control study suggest that full standardization of viral genome detection, including all steps of the procedure, is necessary and that the laboratories performing PCR should participate in repeated quality control studies, whatever technique is being used.

Hepatitis C virus genotypes in France: relationship with epidemiology, pathogenicity and response to interferon therapy. The GEMHEP.

The aim of this study was to investigate the following in a large population of French patients with chronic hepatitis C: the geographical distribution of hepatitis C virus (HCV) genotypes; the relationship between HCV genotypes and epidemiological characteristics; severity of the disease; and response to interferon (IFN) therapy. Data from 14 tertiary referral centres, corresponding to 1872 patients with chronic hepatitis C, were prospectively collected from 1989 to 1997. HCV genotyping was performed using the line probe assay (LiPA). HCV genotypes 1b, 3, 1a, 2, 4 and a mixed infection were found in 41%, 22%, 16%, 11%, 4% and 4% of our population, respectively. HCV genotype distribution was homogeneous, except for genotype 2 that was found more frequently in the southwest than in the other regions (21% vs 9.2%) (P=0.001). HCV distribution was associated with gender, age, and source and duration of infection. In multivariate analysis, these correlations were related to the source of infection, which was the only independent factor significantly associated with genotype (P=0.001). Genotype 1b was significantly more common in patients with cirrhosis, but in multivariate analysis cirrhosis was independently related to older age at exposure and longer duration of infection (P=0.001). A sustained response to IFN therapy was observed in 11% of patients infected with genotypes 1a or 1b vs 32% of those infected with genotypes 2 or 3 (P=0.001). This study shows that HCV genotype is mainly related to the source infection, but not to the intrinsic pathogenicity of HCV, and is a strong predictor of sustained response to therapy.

Screening for HBV, HCV and HIV genomes in blood donations: shortcomings of pooling revealed by a multicentre study simulating real-time testing.

This study was undertaken in order to determine whether screening of viremic blood donations by testing of pooled donor samples could constitute a technically feasible transfusional safety measure. A pilot study of real-time simulation, on a day-to-day basis, of screening of three viral genomes (hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV)) was conducted by five French Blood Centers on plasma samples collected from blood donors and studied within undiluted samples and within sample pools of various sizes. This study was carried out within time conditions compatible with the release of platelets. For the detection of HCV and HIV genomes, the five laboratories achieved a sensitivity that decreased with the size of the sample pool. Four were successful in detecting all undiluted samples. In the 1/10 diluted samples, four failed to detect one HIV or HCV sample. In the 1/100 diluted samples, all laboratories failed to detect one or more HIV or HCV samples. For HBV genome, no participating laboratories detected all of the samples of the panel, even undiluted samples, and the sample pooling considerably affected sensitivity. The improvement and standardization of assays needs to be attained, and training of laboratories appears to be a step crucial for routine screening of viral genomes in blood donations.

Prevalence of GBV C/HGV RNA and GBV C/HGV antibodies in French volunteer blood donors: results of a collaborative study.

BACKGROUND AND OBJECTIVES: Posttransfusion hepatitis still occurs at an incidence of about 1 in 118,000 for HBV and 1 in 220,000 for HCV. This collaborative study aimed to determine the prevalence of a novel flavivirus, GBV-C/HGV, even though its role in transfusion-associated hepatitis is uncertain. MATERIALS AND METHODS: GBV-C/HGV RNA was detected by PCR using either the Boehringer detection kit or by primers previously described. HGV antibodies were detected by a serological assay from Boehringer. RESULTS: The observed GBV-C/HGV RNA frequency was 3.4%. HGV antibodies occurred in 9.5% of donors. CONCLUSION: In our study, 12. 9% of the donors had been in contact with the GBV-C/HGV virus.

Screening blood donations for viral genomes: multicenter study of real-time simulation using pooled samples on the model of hepatitis C virus RNA detection.

BACKGROUND: The systematic screening for several blood-borne viral genomes in blood donations is a complementary safety measure planned or discussed by the national authorities of several countries. STUDY DESIGN AND METHODS: To appreciate the feasibility of such screening using pooled samples, a multicenter study of real-time simulation has been performed on the model of hepatitis C virus (HCV) infection. Four blood transfusion center laboratories and two research and diagnosis laboratories simultaneously screened, by several HCV RNA polymerase chain reaction assays, a panel of plasma sample pools of different sizes (500, 100, and 10 samples), collected from HCV-infected or HCV-uninfected blood donors. One viremic plasma was introduced in each pool. HCV RNA was detected by in-house polymerase chain reaction procedures or by standardized manual or semi-automated polymerase chain reaction assays. RESULTS: The results indicate the feasibility of sample pooling, which renders the screening for viral genomes by molecular biology techniques applicable in the short term and the importance of the experience of laboratory personnel in the use of molecular biology tools. CONCLUSION: The improvement of standardized assays needs to be continued, and training of laboratory staff members appears to be a crucial step before systematic screening of blood donations for viral genomes by molecular biology techniques can occur.

[Rapid progress of cirrhosis in hepatitis C: the role of age at the time of viral contamination]. / Rapidité d'évolution vers la cirrhose après hépatite C: influence de l'âge au moment de la contamination par le virus.

OBJECTIVE: The aim of this study was to assess predictive factors for the progression to liver cirrhosis in hepatitis C. METHODS: One hundred thirty six patients (79 men; 57 women; mean age 39 years) with transfusion or intravenous drug use-associated hepatitis C virus (HCV) infection were studied. Sex, cause of infection, duration of contamination, and genotype were studied as predictive factors of progression to liver cirrhosis. RESULTS: One hundred twenty three patients presented with chronic hepatitis without cirrhosis and 13 had cirrhosis. At the time of liver biopsy, rates of cirrhosis were: 0% before 40 years, 10% between 40 and 60 years, and 47% after 60 years. (p < 0.05). Rates of cirrhosis according to the age at the time of contamination were as follows: 3% before 30 years; 16% between 30 and 50 years; 46% after 50 years even though duration of the disease was comparable in the three groups. In multivariate analysis, two independent factors were associated with liver cirrhosis: age at contamination and duration of infection. CONCLUSION: Duration of infection and especially age at contamination seem better correlated with the probability of cirrhosis than the route of transmission or the genotype 1b. The results of this study suggest that progression to cirrhosis is slower in cases of contamination before 30 years of age than later on. Age at the time of contamination is an important predictive factor of progression to cirrhosis.

GEMHEP multicenter quality control study of PCR detection of GB virus C/hepatitis G virus RNA in serum.

PCR is, to date, the only available tool for the detection of GB virus C (GBV-C) and hepatitis G virus (HGV) RNAs. Twenty-two French laboratories participated in a quality control study to assess the sensitivity and specificity of their procedures. The panel included 13 positive controls and 7 negative controls. The laboratories used either in-house PCR techniques adapted from the literature or partly standardized commercial tests. Three laboratories performed faultlessly with the entire panel. Most laboratories had excellent specificity (100% in 20 of 22 laboratories). Sensitivity was acceptable (85 to 100%) in 15 centers and insufficient (38 to 77%) in 7. As with nonstandardized in-house PCR, the commercial assays gave discrepant performances in different laboratories. These results suggest that laboratories willing to use PCR for detection of GBV-C/HGV RNA for research or diagnostic purposes should participate in multicenter quality control trials.

Contribution of polymerase chain reaction and radioimmunoprecipitation assay in the confirmation of human T-lymphotropic virus infection in French blood donors. Retrovirus Study Group of the French Society of Blood Transfusion.

BACKGROUND: To verify the criteria for human T-lymphotropic virus (HTLV) seropositivity in Western blot (WB) proposed by the Retrovirus Study Group of the French Society of Blood Transfusion, 186 blood donations that were repeatedly reactive in HTLV enzyme-linked immunosorbent assay, selected according to their WB pattern, were tested by polymerase chain reaction (PCR) and radioimmunoprecipitation assay (RIPA). STUDY DESIGN AND METHODS: In two commercially available WBs, 12 samples were confirmed as positive (rgp21+p19+p24) and 174 were interpreted as indeterminate (one or two reactivities to these proteins). The primer pairs used for the PCR allowed the amplification of type I (HTLV-I) or type II (HTLV-II) (or both) sequences. The RIPA was performed with two 35S-labeled cell lines: HTLV-I infected HUT 102/B2 and HTLV-II-infected MoT. RESULTS: Of the 12 positive samples, 11 were classified as HTLV-I-positive and one as HTLV-II-positive. Among the 174 indeterminate samples, three (WB pattern: rgp21+, p19+, p24-) were HTLV-I positive in PCR (one of them was positive in RIPA also); the other 171 were HTLV negative. CONCLUSION: In the study of a population in which 97 percent of HTLV infections are due to HTLV-I, these data support the three-protein criteria (rgp21, p19, and p24) for a positive blot reading. No HTLV infection was observed when rgp21 did not react. Consequently, p19 and/or p24 band patterns represent false reactivity and do not require PCR or RIPA confirmation. To discriminate between false- and true-positive results in the absence of MTA-1 or K55 reactivity, PCR and/or RIPA is required only when rgp21 reactivity is associated with one gag band (p19 or p24).

Indeterminate third-generation recombinant immunoblot assay in hepatitis C virus infection. Group d'Etudes Moléculaires des Hépatites (GEMHEP).

Third-generation recombinant immunoblot assay is widely used for the validation of the serological diagnosis of hepatitis C virus infection. To determine whether indeterminate recombinant immunoblot assay 3.0 patterns may be associated with viral replication and liver disease, 89 indeterminate patterns were studied (67 c22n 14 c33c, 5 c100p and 3 NS5); 35 (39%) had immunosuppression. Serum alanine aminotransferase activity was increased in 49 (55%); HCV RNA was evidenced through polymerase chain reaction in 52 (58%). The observation of indeterminate recombinant immunoblot assay 3.0 justifies investigation of liver disease and search for HCV RNA, since a large proportion of individuals with such patterns are hepatitis C virus-infected.

Multicentre quality control of polymerase chain reaction for detection of HIV DNA.

OBJECTIVE: Seven French laboratories tested the specificity and sensitivity of the polymerase chain reaction (PCR) for the detection of HIV-1 DNA. METHODS: Following its own PCR protocols, each laboratory independently tested blind two panels of 20 coded peripheral blood mononuclear cell samples collected from HIV-1-seropositive individuals and from HIV-1-seronegative individuals at high or low risk of HIV infection. For the first panel, laboratories were free to select type and number of primers; for the second, all were required to use the two primer pairs Pol 3/4 and MMy 9/10' (Nef 1). RESULTS: False-positive and false-negative results were observed in all laboratories (concordance with serology ranged from 40 to 100%). In addition, the number of positive PCR results did not differ significantly between high- and low-risk seronegatives. The use of crude cell lysates in DNA preparation produced the same PCR results as phenol-extracted DNA. Discrepancies between laboratories indicated that factors other than primer pairs contributed strongly to laboratory variability. CONCLUSIONS: Our results emphasize the importance of both positive and negative controls in PCR and demonstrate the value of multicentre PCR quality control.

Human adenovirus-host cell interactions: comparative study with members of subgroups B and C.

Host cell interactions of human adenovirus serotypes belonging to subgroups B (adenovirus type 3 [Ad3] and Ad7) and C (Ad2 and Ad5) were comparatively analyzed at three levels: (i) binding of virus particles with host cell receptors; (ii) cointernalization of macromolecules with adenovirions; and (iii) adenovirus-induced cytoskeletal alterations. The association constants with human cell receptors were found to be similar for Ad2 and Ad3 (8 x 10(9) to 9 x 10(9) M-1), and the number of receptor sites per cell ranged from 5,000 (Ad2) to 7,000 (Ad3). Affinity blottings, competition experiments, and immunofluorescence stainings suggested that the receptor sites for adenovirus were distinct for members of subgroups B and C. Adenovirions increased the permeability of cells to macromolecules. We showed that this global effect could be divided into two distinct events: (i) cointernalization of macromolecules and virions into endocytotic vesicles, a phenomenon that occurred in a serotype-independent way, and (ii) release of macromolecules into the cytoplasm upon adenovirus-induced lysis of endosomal membranes. The latter process was found to be type specific and to require unaltered and infectious virus particles of serotype 2 or 5. Perinuclear condensation of the vimentin filament network was observed at early stages of infection with Ad2 or Ad5 but not with Ad3, Ad7, and noninfectious particles of Ad2 or Ad5, obtained by heat inactivation of wild-type virions or with the H2 ts1 mutant. This phenomenon appeared to be a cytological marker for cytoplasmic transit of infectious virions within adenovirus-infected cells. It could be experimentally dissociated from vimentin proteolysis, which was found to be serotype dependent, occurring only with members of subgroup C, regardless of the infectivity of the input virus.