Bloodworks Northwest is a blood bank and medical research institute headquartered in Seattle, Washington, that serves 90 hospitals in western Washington and Oregon. It has formerly been known as the Puget Sound Blood Center and King County Central Blood Bank.The organization is accredited by AABB (formerly the American Association of Blood Banks), licensed by the Food and Drug Administration; and holds membership in America's Blood Centers (ABC), Blood Centers of America (BCA), and the Alliance for Community Transfusion Services (ACTS).
BACKGROUND AND OBJECTIVES:Cold-stored platelets (CSPs) can form aggregates, ultimately rendering them unusable. The causes of these aggregates and how to prevent them are poorly understood. This study aimed to identify potential factors associated with aggregate formation in CSPs stored in plasma for up to 14 days. MATERIALS AND METHODS:We obtained CSPs from 79 unique donors during a clinical trial. We retrospectively analysed aggregate rates among donors of different sexes, ages and blood groups. In a subgroup, samples were also tested by enzyme-linked immunosorbent assay for markers of thrombosis and inflammation. Platelets from mice lacking von Willebrand factor (VWF) and human apheresis platelets treated with VWF and caplacizumab were stored and assessed for platelet count and aggregate formation by visual inspection and flow cytometry. RESULTS:Forty-five (57%) units developed aggregates, and 34 (43%) did not. Units with aggregates had significantly lower soluble thrombomodulin levels and higher VWF levels approaching significance. In a multivariate analysis, platelets from female donors and donors with ABO type A were significantly more likely to form aggregates than those from male donors and donors with ABO type O, respectively. In the oldest donor cohort, units with aggregates were significantly less common than those without. Interfering with VWF levels and VWF function during storage did not reliably cause or prevent aggregates. CONCLUSION:Donor sex, age, ABO type and thrombomodulin were significantly associated with aggregate formation or prevention.
Fostamatinib had 46% durable response, with 73% steroid reduction, in this multicentre retrospective study of refractory wAIHA/ES. Hypertension, gastrointestinal (GI) distress and neutropenia occurred in 23%. Only one patient required drug discontinuation and one patient dose reduction. In an eight-patient subset, migration inhibitory factor (MIF) levels, naïve (CD62Lhi) T-cell and HLA-DRhi monocyte subsets each correlated with treatment response.
Platelet transfusions are a critical and life-saving intervention utilized in bleeding patients and those at risk of bleeding. The laboratory assessment of fresh or stored platelets, both before and after transfusion, is of interest in licensing and basic science research. Platelets can be given either allogeneic (i.e., from a genetically different donor) or autologous (i.e., donor and recipient are the same, or genetically identical). In this protocol, we demonstrate how to distinguish circulating endogenous platelets from transfused platelets using biotinylation (useful for autologous and allogeneic transfusions) and HLA antibodies (practical in allogeneic transfusion scenarios) to differentiate between circulating endogenous and transfused platelets. Our described methodology not only enables the tracking of platelets but also facilitates post-transfusion functional assessment and the evaluation of platelet function post-transfusion using flow cytometry.
