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Transplantation across the ABO barrier is sometimes done in cases of emergency, such as acute liver failure, but is also carried out in elective cases, e.g. kidneys from living donors. Reducing the recipient anti-A/B antibody titres is often necessary in ABO-incompatible kidney transplantation. This is usually done by the use of techniques such as plasmapheresis and protein A- or sepharose-linked anti-human Ig immunoadsorption. A new ABO immunosorbent with synthetic A- or B-trisaccharide carbohydrate epitopes linked to a sepharose matrix has been tested. Columns made of this material have been tested in vitro with plasma from A- and B-individuals, assessed for antibody reduction capacity, flow characteristics, biocompatibility, and unspecific protein adsorption. The columns have a high capacity for ABO antibody removal, reducing titres by three to seven steps in one passage. We noted a high biocompatibility, with no unspecific protein adsorption, no activation of coagulation factors, and a low activation of complement, no immune complex formation and no cytotoxicity towards cultured mammalian L929 cells.

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SUMMARYWe have investigated the cross-reactivity of various species iti neoepitope-specific methods for quantification of human complement aclivatlon products. In contrast to most other species examined, baboon showed a substantial cross-reactivity supporting a high degree of homology between human and bahoon complement. An assay for C3b, iC3b and C3c (MoAh bH6) showed moderately good reactivity, in contrast to a C3a assay which did not cross-react. Excellent reactivity was found for C5a using MoAbs C17,'5 and G25/2. The reactivity of an established TCC assay (MoAb aBll to a C9 neoepitopc and polyclonal antibody to C5) was improved substantially by replacing the anti-C5 antibody with a new MoAb to C6 particularly selected on the basis of baboon cross-reactivity. Plasma samples from baboons receiving 25 x 10"* and I Ox \^''" \\\Q Escherichia loH bacteria/kg were examined with the assays described. In vivo complement aetivation with the lowest dose was moderate and kept under control, in contrast to the highest dose, where an uncontrolled increase in all activation products continued throughout the infusion period. These results support the hypothesis that sufficiently high amounts of endotoxin lead to uncontrolled activation of complement as seen in irreversible septic shock. The results arc discussed with particular emphasis on activation of the terminal complement pathway.

Purpose: To determine whether salvaged autologous blood collected postoperatively contains complement split products (SC5b-9), and pro-inflammatory cytokines (IL-6 and IL-8) and whether there are any differences between blood collected during hip or knee surgery.Methods: Fifty-eight consecutive patients undergoing hip or knee replacement surgery were studied. Thirty-eight had postoperative bleeding large enough to require infusion of salvaged blood. The salvaged blood was filtered during collection through a 200 µm filter and before infusion a 40 µm filter was used. Samples for complement and cytokine determinations were drawn from the circulation and from the collected blood.Results: High concentrations of SC5b-9, IL-6, and IL-8 were found in salvaged blood. The concentrations were higher than in the circulation (P < 0.05). The circulating concentrations of IL-6 and IL-8 were increased 60 min and 12-18 hr after transfusion. There were no differences regarding SC5b-9, IL-6, and IL-8 in the blood collected after hip or knee surgery.Conclusion: Blood collected from a surgical wound contains large concentrations of inflammatory mediators. There were no differences between blood collected during hip or knee surgery.Objectif : Déterminer si la récupération postopératoire de sang autologue contient des produits de dégradation du complément (SC5b-9) et des cytokines pro-inflammatoires (IL-6 et IL-8), et s'il y a des différences avec le sang prélevé pendant l'opération de la hanche ou du genou.Méthode : L'étude a porté sur 58 patients successivement admis pour la mise en place d'une prothèse de hanche ou du genou. Chez 38 d'entre eux, les pertes sanguines postopératoires ont été assez importantes pour néces-siter la transfusion de sang récupéré. Ce sang a été filtré pendant le prélèvement avec un filtre de 200 µm et avant la transfusion avec un filtre de 40 µm. Des échantillons retenus de la circulation et du sang récupéré ont servi à déterminer la cytokine et le complément.

The study showed a greater increase in cytokine concentration after autologous blood transfusion than after allogeneic blood transfusion. The lower response in the latter may result from transfusion-induced suppression of cellular immunity.

The associations between tumor necrosis factor (TNF) gene polymorphism, plasma cytokines, and cardiopulmonary function after elective cardiac surgery were evaluated. Patients homozygous for the TNFB2 allele displayed larger concentrations of TNF-alpha and interleukin-6 and had an increased risk of developing left ventricular and pulmonary dysfunction compared with TNFB1 homo- or heterozygotes.

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