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Background: Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a condition during pregnancy, which can lead to thrombocytopenia and a bleeding tendency with intracranial hemorrhage (ICH) being the most concerning complication in the fetus or neonate. An incompatibility between human platelet antigen (HPA)-1a accounts for the majority of FNAIT cases. Binding of HPA-1a-specific alloantibodies to their target on fetal platelets and endothelial cells can induce apoptosis of megakaryocytes, disrupt platelet function, and impair angiogenesis. Currently, there is no screening program to identify pregnancies at risk for severe disease. A better understanding of HPA-1a-specific antibody heterogeneity in FNAIT could aid in identifying pathogenic antibody properties linked to severe disease., Study Design and Methods: This study aimed to isolate HPA-1a-specific B-cells from an HPA-1a-alloimmunized pregnant woman. Using fluorescently labeled HPA-1a-positive platelets, single B-cells were sorted and cultured for 10 days to stimulate antibody production. Subsequently, supernatants were tested for the presence of antibodies by enzyme-linked immunosorbent assay and their reactivity towards HPA-1a-positive platelets. Amplification and sequencing of variable regions allowed the generation of monoclonal antibodies using a HEK-Freestyle-based expression system., Results: Three platelet-specific B-cells were obtained and cloned of which two were specific for HPA-1a, named D- and M-204, while the third was specific for HLA class I, which was named L-204., Discussion: This study outlined an effective method for the isolation of HPA-1a-specific B-cells and the generation of monoclonal antibodies. Further characterization of these antibodies holds promise for better understanding the pathogenic nature of alloantibodies in FNAIT., (© 2024 The Authors. Transfusion published by Wiley Periodicals LLC on behalf of AABB.)

Purpose: Three feasible cooling methods for treatment of hyperthermic individuals in the military, that differed considerably in water volume needed (none to ~80 L), were evaluated., Methods: Ten male soldiers were cooled following exercise-induced hyperthermia (rectal temperature (T re ) ∼39.5 °C) using ventilation by fanning (1.7 m s -1 ), ventilation by fanning (1.7 m s -1 ) while wearing a wet t-shirt (250 mL-27 °C water) and tarp assisted cooling with oscillations (80 L of 27.2 ± 0.5 °C water; TACO)., Results: Cooling rates were higher using TACO (0.116 ± 0.032 °C min -1 ) compared to ventilation (0.065 ± 0.011 °C min -1 , P<0.001) and ventilation in combination with a wet t-shirt (0.074 ± 0.020 °C min -1 , P=0.002). Time to cool (TTC) to T re =38.2 °C for TACO was shorter (14 ± 4 min) compared to ventilation only (20 ± 5 min; P=0.018), but not to ventilation while wearing a wet t-shirt (18 ± 6 min; P=0.090)., Conclusions: TACO may be an acceptable, efficient and feasible cooling method in case of exertional heat stroke. However, in case of limited water availability, transportat should be prioritized, and cooling of any form should be implemented while waiting for and during transport., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)