Measurement of phosphatidylserine exposure during storage of platelet concentrates using the novel probe lactadherin: a comparison study with annexin V.
Transfusion
; 49(1): 99-107, 2009 Jan.
Article
em En
| MEDLINE
| ID: mdl-18954406
ABSTRACT
BACKGROUND:
Annexin V binding to platelets (PLTs) is considered the gold standard for monitoring phosphatidylserine (PS) exposure. However, recent comparison of annexin V with the new calcium-independent PS probe lactadherin revealed that annexin V requires a certain threshold of PS exposure (2%-8%) for binding to occur. The aim of this study was to compare annexin V and lactadherin labeling of PLTs in PLT concentrates (PCs). STUDY DESIGN ANDMETHODS:
Optimal labeling conditions for lactadherin and annexin V were established and then compared in either resting or calcium ionophore (CI)-activated PLTs from normal whole blood. Furthermore, 40 PCs (20 apheresis-derived and 20 pooled buffy coat-derived) were stored under standard blood bank conditions and PLT activation was monitored by measuring PS exposure with annexin V and lactadherin along with CD42b, CD61, and CD62P by flow cytometry on Days 1, 3, 5, and 7.RESULTS:
Lactadherin reported a higher exposure of PS than did annexin V in normal PLTs at submaximal doses of CI. PLTs from both types of concentrate, as expected, demonstrated evidence of increased activation during storage using annexin V, lactadherin, CD42b, or CD62P. However, a significantly higher percentage of PS-positive PLTs was found with lactadherin than annexin V.CONCLUSION:
PS exposure on the surface of stored PLTs has been previously underestimated due to the wide use of annexin V. Lactadherin provides a truer reflection of the degree of PS exposure and offers a new calcium-independent approach to studying PLT activation and/or apoptosis.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fosfatidilserinas
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Preservação Biológica
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Plaquetas
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Sondas Moleculares
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Anexina A5
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Proteínas do Leite
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Antígenos de Superfície
Limite:
Humans
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article