New approach to 'top-and-bottom' whole blood separation using the multiunit TACSI WB system: quality of blood components.

BACKGROUND AND OBJECTIVES: TACSI whole blood system is designed to combine primary and secondary processing of six whole blood bags into plasma units, buffy coat and red blood cell concentrates. The aim of this study was to investigate the specifications and in vitro storage parameters of blood components compared with standard centrifugation and separation processing. MATERIALS AND METHODS: Whole blood bags, collected in CRC kits, were treated on a TACSI whole blood system. They were compared with whole blood bags collected in Composelect kits. In addition to routine quality control analyses, conservation studies were performed on red blood cell concentrates for 42 days and on plasma for 6 months. Platelets pools with five buffy coats were also created, and cellular contamination was evaluated. RESULTS: Red blood cell concentrates produced from TACSI whole blood met European quality requirements. For white blood cell count, one individual result exceeded 1 × 10(6) cells/unit. All plasma units fell within specifications for residual cellular contamination and storage parameters. The performances of the TACSI whole blood system allow for the preparation of low volume buffy coats with a recovery of 90% of whole blood platelets. Haemoglobin losses in TACSI BC are smaller, but this did not result in higher haemoglobin content of red cells. These BC are suitable for the production of platelet concentrates. CONCLUSION: From these in vitro data, red blood cell concentrates produced using TACSI whole blood are suitable for clinical use with a quality at least equivalent to the control group.

Study of coagulation function in thawed apheresis plasma for photochemical treatment by amotosalen and UVA.

BACKGROUND AND OBJECTIVES: Photochemical treatment (PCT) based on amotosalen and ultraviolet A light (UVA) demonstrated a wide range of pathogen inactivation. However, coagulation proteins are affected by this treatment. The aim of this study was to evaluate the coagulation parameters in apheresis plasma units after thawing and processing by PCT. MATERIALS AND METHODS: Thirty apheresis plasma units were rapidly frozen at

First-time whole blood donation: A critical step for donor safety and retention on first three donations.

AIM OF THE STUDY: Whole blood donation is generally safe although vasovagal reactions can occur (approximately 1%). Risk factors are well known and prevention measures are shown as efficient. This study evaluates the impact of the donor's retention in relation to the occurrence of vasovagal reaction for the first three blood donations. MATERIAL AND METHODS: Our study of data collected over three years evaluated the impact of classical risk factors and provided a model including the best combination of covariates predicting VVR. The impact of a reaction at first donation on return rate and complication until the third donation was evaluated. RESULTS: Our data (523,471 donations) confirmed the classical risk factors (gender, age, donor status and relative blood volume). After stepwise variable selection, donor status, relative blood volume and their interaction were the only remaining covariates in the model. Of 33,279 first-time donors monitored over a period of at least 15 months, the first three donations were followed. Data emphasised the impact of complication at first donation. The return rate for a second donation was reduced and the risk of vasovagal reaction was increased at least until the third donation. CONCLUSION: First-time donation is a crucial step in the donors' career. Donors who experienced a reaction at their first donation have a lower return rate for a second donation and a higher risk of vasovagal reaction at least until the third donation. Prevention measures have to be processed to improve donor retention and provide blood banks with adequate blood supply.

[Analysis of 516 reports of reactions after the transfusion of labile blood products]. / Analyse de 516 rapports de réaction après transfusion de produits sanguins labiles.

BACKGROUND: In order to assess the implemented preventive measures of transfusion reactions (TR) and to make a study of residual reactions, we analyzed 516 TR reports from 14 hospitals, for three years since 1996 to 1998. METHODS: Clinical signs were classified according to seven etiologic categories. Systematic anti-erythrocyte and anti-leucocyte detection, as well as bacterial control of the returned bag were performed. RESULTS: The TR incidence is 3.7 per 1.000 products. Platelet concentrates (PC) provoke 7.4 TR per 1.000 transfusions, and red cell concentrates (RCC) 3.8. There are as many TR with apheresis platelets (AP), pre-storage leuco-depleted, as with random platelets, post-storage leuco-depleted, and as many with leuco-depleted RCC as with non leuco-depleted RCC. Leuco-depleted AP provoke more allergic reactions than other blood components. TR with AP are much more frequent in children than in adults. Plasma removal from AP before transfusion decreases reaction frequency. CONCLUSIONS: The lack in efficacy failure of pre-storage deleucocytation in TR prevention should be due to related patient factors. Etiology of AP allergic reactions deserves further study. PC suspension in synthetic medium before transfusion is an efficient means for RT decreasing. Hemovigilance system has to be improved so that all TR be reported.

Prestorage leukocyte reduction with in-line filtration of whole blood: evaluation of red cells and plasma storage.

OBJECTIVES: Prestorage filtration of blood components appears to be an effective method to reduce leukocyte-induced adverse reactions and other complications. To determine whether it is better to filter whole blood before component separation, we compared the efficiency of in-line filtration of whole blood with that of postseparation filtration. METHODS: Blood was collected from normal, healthy donors into either regular triple-bag containers or into whole-blood integral-filter container systems. We then compared the in vitro storage values of leukocyte-depleted red blood cell concentrates (RBCC) kept at 4 degrees C, and plasma frozen for 1 year with nonfiltered blood components as control. RESULTS: All counts of white blood cells after filtration were < 1 x 10(6) per unit. For almost all storage parameters no significant differences were found between leukocyte-reduced RBCC and control units. The plasma fibrinopeptide A values below 30 ng/ml prior to freezing indicate that filtration does not activate the coagulation factors. Furthermore, the filtration did not influence either the biological values or the coagulation factors of plasma units. CONCLUSIONS: Whole blood filtration prior to component preparation seems to offer a useful alternative technique for obtaining leukocyte-reduced RBCC and plasma.

Production of stable human-mouse hybridomas secreting monoclonal antibodies against Rh D and c antigens.

Peripheral blood lymphocytes from donors immunized against Rh antigens were fused with mouse myelomas and heteromyelomas in order to obtain human-mouse hybridomas secreting antibodies specific for these antigens. Three cell lines secreting anti-D IgG and two secreting anti-c IgM were stabilized and produced immunoglobulins for several months. These human monoclonal antibodies were evaluated as reagents for Rh phenotyping. Their complementary activity towards weak D and partial D antigens is examined.

[Production of monoclonal antibodies specific for the ABO blood group and rhesus D antigens]. / Production d'anticorps monoclonaux spécifiques des antigènes des groupes sanguins ABO et Rhesus D.

We report, in this work, the techniques to obtain four monoclonal antibodies specific of erythrocytes antigens. Three of this antibodies, react with the ABO Blood Groupe System (A,B and AB), are produced by three mouse hybridomas (M18-2F11, M18-4F6 et M19-45D6), obtained by fusion of Sp2/0 mouse myeloma cell with spleen cell of balb/c mice immunized with human red blood cells and selected on selectif medium (Hypoxanthin, Aminoptérin, Thymidin) (HAT) and cloned by four limiting dilutions. Where as the fourth, it is an human monoclonal antibodies against Rhesus (D) produced by heterohybridomas, realized by fusion of X63 mouse myeloma cell with human B lymphocytes, from actively immunized persons by D antigen, that are purified and transformed by Epstein-Barr virus (EBV), and selected on selectif medium (HAT), presence of ouabain and then cloned by four limiting dilutions. The specificity of the antibodies produced, has been determined by direct hemagglutinin for the mouse monoclonal antibodies and artificial for the human anti-D. The determination of isotype the heavy and light chains is released by the technique immunoenzymatique (ELISA) and immunofixation has shown that mouse monoclonal antibodies belong to class IgM kappa, and human monoclonal antibodies anti-D belong to class IgG lambda.

Influence of affinity of antibodies upon their detection by liquid phase radiobinding assay and solid phase enzyme linked immunosorbent assay. Demonstration using monoclonal antibodies raised against rDNA human proinsulin.

Hybridomas producing proinsulin antibodies were cloned by limiting dilution of cell cultures obtained by fusion of splenocytes of immunized mice with immortal myeloma cells. Some proinsulin monoclonal antibodies crossreacted with labelled insulin but none did with labelled C-peptide indicating that the involved epitopes were at one of the insulin/C-peptide junctions or included in the insulin moiety. Hybridoma supernatants were assayed for IgG concentration by a solid phase assay and for ligand binding by a radiobinding assay and an enzyme linked immunosorbent assay. The half-life of immune complexes formed with radioligand was measured and, as expected, correlated with affinity as measured by the method of Scatchard. Antibody titres determined by enzyme linked immunosorbent assay did not correlate to those measured by radiobinding assay. IgG concentration correlated to enzyme linked immunosorbent assay titres but not to radiobinding assay titres. Finally, a significant correlation was found between radiobinding assay titre and the product of enzyme linked immunosorbent assay titre by the period of immune complexes. It is concluded that, except for very low affinity antibodies, enzyme linked immunosorbent assay is a capacity assay whereas radiobinding assay is influenced by both antibody concentration and affinity. The former assay is thus best suited to detecting low affinity antibodies whereas the latter is more efficient in the presence of low levels of high affinity antibodies.

Radioimmunoassay for albuterol using a monoclonal antibody: application for direct quantification in horse urine.

A monoclonal antibody was synthesized in mouse against the O-(3-carboxypropionyl) derivative of albuterol linked to bovine serum albumin. Isotyping of this material revealed the IgG1 class characterized by an affinity constant of 1.03 nM-1 and a density of sites of 0.55 nM. This antibody was found specific as its cross-reactivity to structurally related molecules was less than 1% except for clenbuterol (75%). A radioimmunoassay was set up with culture supernatant (final dilution 1/1000) and [3H] albuterol. The calibration curve was characterized by a maximum binding of 28%, an ED50 of 1.15 pmol per tube, the detection limit was 28.8 fmol/tube and the linearity of the response was up to 39.8 pmol/tube. This RIA method has been used for direct quantitation of albuterol in horse urine without any clean-up or extraction step.