We have previously reported bradykinin (BK) generation during filtration of platelet concentrates with leukocyte-reduction filters made of polyester fibers with a negative zeta-potential through contact activation. In the present study we investigated whether BK was generated when red cell concentrates containing MAP (RC-MAP) was filtered with 7 different leukocyte-reduction filters (Filters A-G) made for red cell concentrates.
Mean BK level in RC-MAP stored one day was 39.8±78.8pg/ml before filtration. However, concentration increased several thousand-fold to ng/ml levels during filtration with Filters A-F with a negative zeta-potential. In contrast, generation of BK was suppressed during filtration with Filter G with a positive zeta-potential to a maximum level of 601±350pg/ml.
As the pre-filtration storage period of RC-MAP was extended, BK levels after filtration with Filter A decreased with 95% suppression and almost no BK generation observed in RC-MAP stored for 20 or 43 days. As the post-filtration storage period of RC-MAP was extended, BK levels after filtration with Filter A decreased to pre-filtration levels in 3 hours. Further, kallikrein levels in RC-MAP increased significantly and high molecular weight kininogen levels decreased after filtration with Filter A.
The clinical significance of this BK generation during filtration remains unclear, but should be considered with regard to the clinical application of leukocyte-reduction filters.

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Sera obtained from six patients with recently infected syphilis showed positive reaction by Treponema pallidum Particle Agglutination (TPPA, Fujrebio), a newly developed test for syphilis infection. The results were confirmed by other immunoassays such as enzyme immunoassay (Imzyn M-TP, Fujirebio) and/or immunofluorescence (FTA-ABS, Nihon Touketukansou). In contrast, they were negative by Serodia-TP (Fujirebio). In a seroconversion panel, TPPA showed positive reaction earlier than conventional RPR (rapid plasma reagin, Kaketuken). IgM fractions prepared from five recently infected patients were all positive by TPPA, while only one was positive by Serodia-TP. These results indicate that TPPA is able to detect anti-TP in the early phase of infection. In the next step, we evaluated the application of this test for blood donor screening with a PK7200 automated pretransfusion analyzer for agglutination assays (Olympus). After establishing optinal conditions for TPPA in the PK7200 (PK-TPPA), 4, 902 samples were simultaneously tested by manual and automated testing. Positivesamples were manually retested. There was no false negative results by the PK test, while both the manual PK tests yielded a similar rate of false positive results. In a simultaneous test with PK-TPPA and RPR, respectively 43 and 65 of 14, 106 donor samples were repeatedly positive. Of 21 samples showing positive reaction in both tests, 17 were confirmed as IgG type anti-TP by FTA-ABS. Of 20 PK-TPPA(+)-RPR(-) samples, 7 were IgG type anti-TP positive. None of the 44 RPR(+)-TPPA(-) samples were positive by FTA-ABS. We conclude that the PK-TPPA is sensitive enough to detect IgM type anti-TP and acceptable for donor screening.

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This report describes the present status of transfusion services at night and on weekends at university hospitals (44 national, 8 prefectural and 33 private) in Japan. A total of 79 (92.9%) of 85 hospitals replied to our survey questionnaire.
Surprisingly, more than half (40 hospitals, 50.6%) had absolutely no service at night or on weekends. Twenty-two hospitals (27.8%) had a 24-hour coverage system by medical technologists (21 hospitals) or by physicians. The remaining 17 (21.5%) offered a limited service system, mostly daytime service on Saturaday. This implied that emergency transfusion tests in 58 hospitals (73.4%) were performed by medical doctors at night and holidays. Additionally, even in the hospitals having complete coverage, medical technologist specializing in blood transfusion were continuously available in only two hospitals. Thus, medical technologists not specializing in blood transfusion supported most of the 24-hour transfusion services.
Statistics concerning transfusion error reflect this status. Twenty-nine of 40 hospitals (72.5%) with no service system reported transfusion errors made by doctors. Even in the 18 hospitals with a 24-hour system supported by technologists, 10 (55.5%) experienced errors. These findings contrasted with the complete absence of errors made by medical technologists specializing in blood transfusion throughout the survey.
We conclude that promotion of 24-hour transfusion services supported at least by well-trained technologists and preferably by medical technologists specalizing in blood transfusion, is an urgent necessity at university hospitals in Japan.

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We compared apheresis products collected by two cell separators (Spectra and CS3000) for peripheral blood stem cell harvest (PBSCH), the total number of 110 apheresis procedures were done in 46 patients, who underwent two or three procedures over consecutive days. Respective results for apheresis products collected by Spectra and CS3000 were as follows (mean±standard deviation): whole white cells (×109), 16.2 (±14.0) and 11.1 (±9.15); mononuclear cells (×109), 9.21 (±6.59) and 7.74 (±6.12); CD34-positive cells (×108), 3.20 (±6.49) and 2.06 (±3.78); and CFU-GM (×105), 381 (±687) and 252 (±398). Thus, the ratio of mononuclear cells harvested using CS3000 was higher than that by Spectra (76% vs 68%, p<0.05). Although the ratio of CD34-positive cells was equal between the two products, a greater number of stem cells (CD34-positive cells and CFU-GM) was harvested with Spectra than CS3000 (p<0.05).
These results showed that the purity of mononuclear cells harvested by CS3000 is superior to that by Spectra. However, Spectra was able to collect peripheral stem cells more efficiently.

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Anti-BI antibodys which recognizes both B and I antigen of red blood cells is very rare and its characteristics are not well known. In this study, we report an anti-BI antibody which was detected in a patient with B-cell type acute lymphocytic leukemia (B-ALL). The patient was diagnosed as having A¹B antigen on red cell membranes and an antibody reacted with B cells. However, no unexpected antibody reacting with O cells was found in the patient's serum. The antibody detected in the serum which caused the discrepancy in the diagnosis of ABO typing did not react with Bi-cord or Bi-adult cells but rather with BI cells only. On the basis of this evidence, we determined the specificity of the antibody to be the anti-BI antibody.
The mechanisms of the development of this antibody are unclear. However, because the antibody paralleled the progression of the disease in the patient, the possibility of antigenic change of the red cell membrane, secretion of the antibody from the B-ALL cells, and immunologic abnormalities associated with the ALL were considerd. Clinical significance of this antibody was not evaluated because the patient did not receive blood trnasfusion.

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We experienced a patient with a life-threatening suspected delayed hemolytic transfusion reaction (DHTR). The patient was a 73-year-old female with liver cirrhosis. Her blood type was A+, D+C-c+E+e-. She had has 2 pregrancies and a history of 2 transfusions. She received 1 unit of whole blood and 2 units of concentrated red cells for the treatment of anemia (Hb 7.1g/dl) on December 2 and 3, 1992.
No irregular antibodies were found before transfusion and crossmatch test showed no significant agglutination by the indirect antiglobulin test. Her hemoglobin level dropped to 1.4g/dl between the day 7 to the day 9 after transfusion without any bleeding signs. At the same time GOT, LDH and T. Bil. levels, increased remarkably. However, no hematuria was seen hematuria. Serological studies showed the presence of strong antibodies against high frequency red cell antigen. The antibody was identified as anti-En^a, which is associated with the MNS blood system. Anti-En^a titer increased 16 to 256 times by the saline method, and 256 to 64, 000 times by the indirect antiglobulin test from the day 9 to day 12 after transfusion. These findings strongly suggested DHTR secondary response. The elution test using cells from her elder sister (also En (a-)) showed the existence of anti-C and anti-e. It is therefore difficult to identify the antibody responsible for the DHTR. Reports of anti-En^a are rare, this being only the second case reported in the Japanese literature.

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Bacterial contamination was observed in a platelet concentrate obtained by apheresis using COBE SPECTRA and stored for 45 hours with agitation at 20 to 24°C. The platelet product was contaminated with 10⁷ CFU/ml of Bacillus cereus. The contamination was likely attributable to bacteria on the skin at the phlebotomy site, because 1) apheresis was performed in a closed system and 2) Bacillus cereus are known to exist ubiquitously including the skin surface, and to be resistant to the chlorohexidine-ethanol that is routinely used for disinfection of phlebotomy site in our blood center. In a spike experiment with apheresis platelets, the growth of Bacillus cereus was vey rapid, with a doubling time of 6 hours to reach 10⁷ CFU/ml in 2 days.
Leukocyte depletion resulted in reduced phagocytic activity and allowed rapid growth of the contaminating bacteria in platelet products. There findings enpharize the importance of preventing as far as possible. In addition, platelet recipients, largely comprising leukemia patients, are vulnerable to infection.

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