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SummaryBackground:The Mirasol® pathogen reduction technology (PRT) for platelet concentrates (PC) uses riboflavin and UV light (270–360 nm). We evaluated the impact of PRT on platelets in comparison to standard single-donor PC. Material and Methods:Platelets were resuspended in autologous plasma. After 2 h rest without agitation, PC were split into an untreated control unit (C-PC) and an immediately treated unit (T-PC) (series I). In series IV, split PC were stored under agitation over night before PRT was carried out. Platelet quality was assessed by pH, glucose consumption, lactate production rate, LDH, soluble sCD62p and CD62p expression with and without TRAP (thrombin receptor-activating peptide) over 7 days. Results:Series I: On day 5, pH values were lower for T-PC (6.8 ± 0.2 vs. 7.4 ± 0.1, C-PC), accompanied by a higher glucose consumption rate of 0.069 ± 0.016 vs. 0.035 ± 0.006 mmol/1012platelets/h and lactate production rate of 0.126 ± 0.031 vs. 0.063 ± 0.011 mmol/1012platelets/h. CD62p using TRAP was lower for T-PC (50 ± 11 vs. 62 ± 14). Baseline activation was higher in T-PC (35 ± 12 vs. 28 ± 15). Longer initial rest time had no impact on these results (series II/III/IV). Conclusion:PRT leads to an increase of platelet metabolism and activation independent of the length of the initial rest times. PC resuspended in autologous plasma should be stored at maximum up to day 5.Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

SummaryBackground: The gene locus for the ABO blood group system encodes a glycosyltransferase. Alterations in the DNA sequence are associated with the blood groups and the expression levels of antigens on red blood cells. A number of ABO alleles have been described as the molecular basis of weak A or B antigens. Patients and Methods: Here, we describe a novel variant B allele in a blood donor with discrepant results in routine forward (group A) and reverse (very weak anti-B isoagglutinins) ABO blood grouping. Results: Determination of the ABO genotype using polymerase chain reaction-sequence-specific primers (PCR-SSP) indicated blood group A2B. Sequencing of the ABO gene exons 6 and 7 showed for 1 allele a G insertion into the GGGGGG sequence at position 811–816 of exon 7. The 816insG mutation (designated ABO*Bw20) led to a frame shift of the coding sequence and subsequent alteration of the protein sequence. The location of the mutation on a B allele was proven by PCR-SSP. Screening for the novel mutation in 211 blood donors with regular ABO phenotypes indicated that *Bw20 is a rare variant. Conclusions: The low levels of anti-B isoagglutinins associated with this novel variant indicate that residual undetectable amounts of B antigen may be present on red blood cells. The serological and molecular analysis of members of the blood donor’s family further proved the phenotype-genotype correlation of the *Bw20 allele with antigen·and individually variable levels of anti-B isoagglutinins. The characterization of novel alleles associated with ABO subgroups may ensure the correct determination of blood groups in which serological methods are combined with molecular genetic approaches.Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

SummaryMultipotent mesenchymal stromal cells (MSCs) are currently exploited in numerous clinical trials to investigate their potential in immune regulation, hematopoiesis, and tissue regeneration. The low frequency of MSCs necessitates cell expansion to achieve transplantable numbers. The challenge is to assure safe and high-quality cell production. GMP(Good Manufacturing Practice)-graded cell processing such as cell preparation, culture, and manipulation is mandatory for the progress of such advanced cell therapy. This review summarizes protocols to isolate MSCs from bone marrow and adipose tissue and to expand MSCs for clinical use focussing on culture media composition as well as culture devices and assays to ensure and control quality of the final product.Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]