Soluble antigens in plasma allow mismatched transfusion without hemolysis.

BACKGROUND: Universal plasma is a scarce resource when a massive transfusion protocol has been initiated. Previous studies have reported success using group A plasma in place of the universal plasma, group AB. It is unclear why there are not more reports of hemolytic reactions occurring from this practice. One possible explanation is the presence of water-soluble antigens in the patient plasma that bind to, and neutralize, the soluble antibodies present in the transfused plasma. STUDY DESIGN AND METHODS: Expired units of plasma were used to make dilutions that consisted of mixtures of group A and B plasma and saline. Serial dilutions of these samples were performed starting from undiluted up to 1024. The dilutions were titrated using a group B red blood cell preparation. The titrations were read after incubation. RESULTS: The titers that resulted from the mixed plasma dilutions were significantly lower or showed no agglutination when compared to the group A-specific saline dilutions. The differences between the saline dilutions and mixed group dilutions were significant (p < 0.001). CONCLUSION: Our study shows that secretor status would provide protection from isoantibodies. The dissolved B antigens in the group B plasma absorb and/or bind to the group B isoantibodies in the group A plasma. This mechanism gives a protective effect against hemolytic reactions in massive transfusion situations in the trauma setting when group A plasma is used instead of group AB plasma. This protective effect is revealed with the paucity of intravascular hemolysis observed in these out-of-group massive transfusions.

Aminodifluorosulfinium salts: selective fluorination reagents with enhanced thermal stability and ease of handling.

Diethylaminodifluorosulfinium tetrafluoroborate (XtalFluor-E) and morpholinodifluorosulfinium tetrafluoroborate (XtalFluor-M) are crystalline fluorinating agents that are more easily handled and significantly more stable than Deoxo-Fluor, DAST, and their analogues. These reagents can be prepared in a safer and more cost-efficient manner by avoiding the laborious and hazardous distillation of dialkylaminosulfur trifluorides. Unlike DAST, Deoxo-Fluor, and Fluolead, XtalFluor reagents do not generate highly corrosive free-HF and therefore can be used in standard borosilicate vessels. When used in conjunction with promoters such as Et(3)N.3HF, Et(3)N.2HF, or DBU, XtalFluor reagents effectively convert alcohols to alkyl fluorides and carbonyls to gem-difluorides. These reagents are typically more selective than DAST and Deoxo-Fluor and exhibit superior performance by providing significantly less elimination side products.