BACKGROUND: Platelet (PLT) storage at 0 to 4 degrees C suppresses bacterial multiplication, but induces clusters of glycoprotein (GP) Ibalpha that trigger their phagocytosis by macrophages and reduce their survival after transfusion. A method was sought that detects cold-induced changes in GPIbalpha involved in phagocytosis. STUDY DESIGN AND METHODS: Human PLTs were isolated and stored for up to 48 hours at 0 degrees C. Binding of a phycoerythrin (PE)-labeled antibody directed against amino acids (AA) 1-35 on GPIbalpha (AN51-PE) was compared with phagocytosis of PLTs by matured monocytic THP-1 cells, analyzed by fluorescence-activated cell sorting. RESULTS: Freshly isolated PLTs were detected as a single population of AN51-PE-positive particles and showed less than 5 percent phagocytosis. Cold storage led to a decrease in AN51-PE binding and an increase in phagocytosis. N-Acetylglucosamine, known to interfere with macrophage recognition of GPIbalpha clusters, restored normal AN51-PE binding to cold-stored PLTs and suppressed phagocytosis. CONCLUSIONS: It is concluded that binding of an antibody against AA 1-35 on GPIbalpha reflects changes in GPIbalpha that make PLTs targets for phagocytosis by macrophages.
BACKGROUND: Platelet (PLT) storage at 0 to 4 degrees C suppresses bacterial multiplication, but induces clusters of glycoprotein (GP) Ibalpha that trigger their phagocytosis by macrophages and reduce their survival after transfusion. A method was sought that detects cold-induced changes in GPIbalpha involved in phagocytosis. STUDY DESIGN AND METHODS: Human PLTs were isolated and stored for up to 48 hours at 0 degrees C. Binding of a phycoerythrin (PE)-labeled antibody directed against amino acids (AA) 1-35 on GPIbalpha (AN51-PE) was compared with phagocytosis of PLTs by matured monocytic THP-1 cells, analyzed by fluorescence-activated cell sorting. RESULTS: Freshly isolated PLTs were detected as a single population of AN51-PE-positive particles and showed less than 5 percent phagocytosis. Cold storage led to a decrease in AN51-PE binding and an increase in phagocytosis. N-Acetylglucosamine, known to interfere with macrophage recognition of GPIbalpha clusters, restored normal AN51-PE binding to cold-stored PLTs and suppressed phagocytosis. CONCLUSIONS: It is concluded that binding of an antibody against AA 1-35 on GPIbalpha reflects changes in GPIbalpha that make PLTs targets for phagocytosis by macrophages.
Authors: A J Gerard Jansen; Emma C Josefsson; Viktoria Rumjantseva; Qiyong Peter Liu; Hervé Falet; Wolfgang Bergmeier; Stephen M Cifuni; Robert Sackstein; Ulrich H von Andrian; Denisa D Wagner; John H Hartwig; Karin M Hoffmeister Journal: Blood Date: 2011-11-18 Impact factor: 22.113
Authors: Qiang Peng; Heidi Yeh; Lingling Wei; Keiichi Enjyoj; Zurab Machaidze; Eva Csizmad; Christian Schuetz; Kang Mi Lee; Shaoping Deng; Simon C Robson; James Markmann; Leo Buhler Journal: PLoS One Date: 2012-10-30 Impact factor: 3.240